geodiversitas fait suite.

avec la même tomaison, au Bulletin du

Muséum national d'Histoire naturelle,

4® série, section C. Sciences de la Terre.

Directeur de la publication :

J.C Moreno, Administrateur provisoire du

Muséum national d'Histoire naturelle

Rédacteur en chef :

Hervé Lelièvre

Conseil éditorial :

Annemarie Ohler (Nomenclature)

Assistante de rédaction :

Florence Kerdoncuff

Corrections-relecture :

Hélène Bertini

Comité scientifique :

Jean Broutin (UPMC, Paris)

Bruno David (CNRS, Dijon)

Jean-François Deconinck (USTL, Lille)

Patrick De Wever (MNHN, Paris)

Jean Marcoux (U. Denis Diderot, Paris)

Christian Ravenne (IFP, Paris)

Indexed in

GeoRef (Online Database for Bibliography and Index of

Geology), Biological Abstracts, ASFA (Aquatic Sciences and

Fisheries Abstract), Pascal, Zoological Record

geodiversitas est un trimestriel publié par les Publications Scientifiques du Muséum, Paris

geodiversitas /s a quarterly published by Publications Scientifiques du Muséum, Paris

Abonnement pour l’année 1999 (prix HT)

Annual subscription rates 1999 (excluding VAT)

1000 FF (152,45 euros)

Geodiversitas peut être obtenu par voie d’échange. Pour toutes informations s’adresser à :

Geodiversitas may be obtained on an exchange basis. For further information please write to:

Service des périodiques et des échanges de la Bibliothèque centrale

du Muséum national d’Histoire naturelle

38 rue Geoffroy Saint-Hilaire

75005 Paris

Tél. ; (33) (0)1 40 79 36 41

Fax ; (33) (0)1 40 79 36 56

Les Publications Scientifiques du Muséum publient aussi :

The Publications Scientifiques du Muséum aiso publish:

adansonia

Abonnement / Subscription : 500 FF (76.22 euros)

zoosystema

Abonnement / Subscription : 1000 FF (152,45 euros)

Abonnement général / General subscription (adansonia + geodiversitas + zoosystema) : 1800 FF (274 euros)

geodiversitas

Publications Scientifiques du Muséum, Paris

Photocopies :

Les Publications Scientifii^ues du Muséum adhèrent au Centre

Français d’Exploitation du Droit de Copie (CFC), 20 rue des

Grands Augustins, 73006 Paris. Le CFC est membre de

X International Fédération of Reproduction Rights Organisations

(IFRRO). Aux États-Unis d’Amérique, contacter le Copyright

Clearance Center, 27 Congress Street, Salem, Massachusetts 01970.

national d'Histoire naturelle, Paris, 1999

Photocopies:

The Scientific Publications of the Muséum adhéré to the Centre

Français d'Exploitation du Droit de Copie (CFC), 20 rue des Grands

Au^stins, 75006 Paris. The CFC is a member of International

Fédération of Reproduction Rights Organisations (IFRRO).

In USA, contact the Copyright Clearance Center, 27 Congress Street,

Salem, Massachusetts 01970.

Introduction

Ce volume spécial est le troisième et dernier de la

série des volumes publiés par Geodiversitas dans le

cadre du Programme internationaJ Péri-Tcthys. Il

est consacré aux données obtenues par les scienti¬

fiques russes ayant participés au programme. Les

collaborations établies avec les collègues de la

Communauté des Etats Indépendants (CEI)

représentent un des apports originaux et impor¬

tants de ce programme. En effet» ils ont permis

des échanges d’informations mais aussi de

méthodes. Le résultat est à Tactif du programme.

Certains des résultats scientifiques sont publiés

sous tormes d’articles de corrélations stratigra-

phiques, dans les voluinc.s publics par le program¬

me {Geodiversitas ou Mémoires du Muséum

national d’Histoire naturelle). D’autres acquis

apparaissent sur les cartes paléogeographiques

(Atlas Péri-Téthys a paraître en 2000) qui synthé¬

tisent et illastreni cette Irucuicuse coopération.

Afin de présenter un cn.semble homogène corres¬

pondant aux exigences de qualité requise par le.s

responsables des publications du Muséum, toute.s

les figures de ce volume ont etc redessinées ou

reprises partiellement par les éditeurs. Cerre

tâche a été facilitée par l'intervention d'E. Cam-

breleng (Laboratoire de Géologie, MNHN),

nous lui sommes reconnaissants de l'aide quelle

a apportée.

Nous sommes très redevables au Muséum natio¬

nal d’Histoire naturelle qui nous a permis de

concrétiser cette collaboration avec les collègues

russes. Enfin, nous sommes heureux d’exprimer

notre amicale gratitude à Hervé Lelièvre, rédac¬

teur en chef, et Florence Kerdoneuff, assistante

de rédaction pour leur compétence et leur profes¬

sionnalisme.

Ce volume s’intégre dans la série des publications

du Programme international Péri-Téthys :

This spécial issue is the third artd bist of the sérié

published hy Geodiversitas within the Jimneivork

of the hnernational Peri-Tethys Programme. !t is

devoted to the data ohtamed by the Russiaa scieri’

tists irivolved in the Piagramrne. The çoHaborntions

established ivith r/te colkagncs of the Indépendant

States Community accoum for one of the original

and main contributions of t/te Programme- Indeed.

they allowed exchanges of informations and

metl)üdi, Some remlts are published as stiatigaphic

comlaiioris papers in the spécial volumes published

by the Programme (Geodiversitas and Mémoires

du Muséum national d'Histoirc naturelle^. Some

others appear on the palâeogeogaphic maps (Péri-

Ihthys Atlas will he published in 2000) which syn¬

thétisé and illustrate this fi'ui^l coopération.

In order to présent an homogeneous set which cor¬

responds to the qiiality requests of the Muséum

publication team^ ail the figures were redrawn or

picked again by the editors. We thank for her help

for this Work E. Cambreleng (Laboratoire de

Géologie. MNHN),

We are indehted to the Muséum national dHistoire

naturelle for his contribution in the concrétisation

of the collaboration with our Russian colleagues.

Finally, we would Like to express our friendly gati-

tude ro Hervé Lelievre, Editor in Chief and

Florence Kerdoncujf assistant editor. for their com¬

pétence atîd professionalism.

This volume fits in the sérié of Peri-Tethys Inter¬

national Progamme publications.

GEODIVERSITAS • 1999 • 21 (3)

289

Introduction

Roure F. (ed.) 1994. — Peri-Tethyan Platforms: Proceeding of the IFP Peri-Tethys Research Conférence held in

Arles, France, Mar ch 23, 1993. Technip, Paris, 275 p.

Ziegler P. A. & Horwath F. (eds) 1996, — Peri-Tethys Memoir 2: Structure and prospects of Alpine Basins

and Forelands. Mémoires du Muséum national d'Histoire naturelle, Paris 170, 547 p.

Crasquin-Soleau S. & De Wever P. (eds) 1997. —Peri-Tethys: stratigraphie corrélations 1. Geodiversitas 19

(2) : 169-499.

Crasquin-Soleau S. &: Barrier E. (eds) 1998. — Peri-Tethys Memoir 3: Stratigraphy and évolution of Peri-

Tethyan Platforms. Mémoires du Muséum national d’Histoire naturelle, Paris 177, 262 p.

Crasquin-Soleau S., Izarr A., Vaslet D. & De Wever P. 1998. — Peri-Tethys; stratigraphie corrélations 2.

Geodiversitas 2Q (4) : 519-730.

Crasquin-Soleau S. Barrier E. (eds) 1998. — Peri-Tethys Memoir 4: Epicratonic basins of Peri-Tethyan mar-

gins. Mémoires du Muséum national d’Histoire naturelle, Paris 179, 294 p.

Crasquin-Soleau S. & Barrier E. 1999. — Peri-Tethys Memoir 5: New data on Peri-Tethyan sedimentary

basins. Mémoires du Muséum national d’Histoire naturelle, Paris 182, sous presse.

Sylvie Crasquin-Soleau & Patrick De Wever

290

GEODIVERSITAS • 1999 • 21 (3)

Corrélations between Tatarian (Permian) type

section (Russie) and the Sait Range (Pakistan):

palynology and palaeomagnetism

Alexei V. GOMANKOV

Geological Institute of the Russian Academy of Sciences,

7, Pyzhevsky, Moscow, 109017 (Russia)

gomankov@ginran.m5k.su

Boris V. BUROV

Geological Department, Kazan State University,

18, Kremliovskaya St., Kazan, 420008 Tatarstan (Russia)

Gomankov A. V. & Burov B. V. 1999. — Corrélations between Tatarian (Permian) type sec¬

tion (Russia) and the Sait Range (Pakistan): palynology and palaeomagnetism, in

Crasquln-Soleau S- & De Wever P. (eds), Peri-Tethys: stratigraphie corrélations 3,

Geodiversitas 21 (3) : 291-297.

KEYWORDS

Palaeomagnetism,

palynolog)’,

stratigraphie corrélations,

Permian,

Suit Range.

Rus.sian Plattbrin.

ABSTRACl

The po.sition of palaeomagnctic zones cogether wirh the occurrence of some

miospore species in ihe section of Sait Range cnables its ctirrelation wich the

référence .sections of Tatarian on ihc Russian Plaiform. So chc Wargal

Limestone œrresponds roughl)' to rhe Vishkilsk)' Horizon (newly proposée!

name inste;ul of Sevedrodvinsky Horizon) both boundaries of rhe former

being slighrly younger than the corresponding boundaries of the lutter. The

analogs of the lower pan of VishkÜsky Horizon and of the whole carly

Tatarian are seemingly absent in the Sait Range. The Amb Formation is

most probably of Kazanian âge.

MOTS CLÉS

Palcomagnétismc,

palynologie,

corrélations strarigr^hique.s,

Permien,

Sait Range,

Platc-formc rusye.

RÉSUMÉ

Corrélatiofis entre Lj coupe type (Russie) du Tatarian (Permien) et le Sait Range

(Pakistan) : palynologie et paléomagnétisme.

La position des zones paJéomagncriques associée à la présence de quelques

espèces de miospores dans une coupe du Sait Range, permet des corrélations

avec les coupes de réference du Tataricn de la Pl.ue-fbrme russe. Ainsi le cal¬

caire de Wargal correspond à l’horizon de Vishkilsky (nouveau nom de

l'horizon de Sevedrodvinsky) dont les limites sont légèrement plus jeunes que

celles du calcaire de Wargal. Les analogues de la partie inférieure de l'horizon

de Vishkilsky et de l'ensemble du Tataricn .sont absents dans le Sait Range.

La Formation Amb est plus ptobablemeni datée du Kazanien.

GEODIVERSITAS • 1999 • 21 (3)

291

Gomankov A. V. & Burov B. V.

INTRODUCTION

The well'known section of Permian and Triassic

in thc Salr Range (Pakistan) is in two respects of

great importance for the palynostratigraphy.

Firstly> it yiclds abundanc and wcll-preserved

miospores along with normal marine fauna. And

although the calibration of chis section in terms

of common Tcthys scalc is not quiie distinct as

yct (Foster ^ Jones 19^)4), it srill provides a hope

on thc corrélation between marine and

non-marine scales of Upper Permian and Lower

Triassic.

Secondly, since thc Basic work by Balme (1970)

it is évident, that rlie miospore assemblages from

the Sait Range dcmonsiratc a mixture of forms

rypical For different phylochoria of lhe past

including ihose of botli northern and Southern

hémisphères. It proves to he very usefiil For inter¬

regional palynostratigraphic corrélations proper,

especially in the Late Permian conditions of the

highest jihytogeographical diFFerenriarion of the

Earth. So, Foster (1982) outlined the palynologi-

cal corrélation of the Sidt Range wiih the Easterii

Australia whilc Gomankov (1992) did the same

tor thc Sait Range and the Russian Platform.

The last corrélation may be however defincd

much more exactiy due to the data on the

palaeomagnetism of the section of Nammal

Gorge (Sait Range) published by Haag & Heller

(1991).

PALYNOLOGICAL AND

PALAEOMAGNETIC CORRELATIONS

The Tatarian of the Russian Platform is usually

suhdivided inio two subsiages and three horizons

(from beiow upwards): Uizhumsky» Vishkilsky

[the name ""Vishkilsky Horizon” was receiitly

proposed insread of the name “Severodvinsky

Horizon”, which turned to be invalid by nomen¬

clature reasons (Gomankov 1997)], and Vyàtsky,

the first of them being early Tatarian and the rwo

others being latc làtarian. Bcsides thaï the type

sccuon oF thc Tatarian ar the Vyatka River was

divided by Forsch (1963) into cIcA^en tinits callcd

“beds” each of them having received ics own geo-

graphical name (Fig. 1). Due to the numerous

palaeomagnetic studics of the Russian Platform

Permian (e.g.^ Boronin 1979, 1990; Burov étal.

1996b), six palaeomagnetic zones were recogni-

sed in the Tararian, three of them (R, R R^R R^P)

being of fcvcrsal polaricy» onc (NRP) of variable

polarity, and two (N,R N,P) of normal polarity

(see Fig. 1 for relaiionship of this zonation with

the above menrioncd subdivisions of the

Tatarian).

The bouiidane.s of ihe palaeomagnetic zones in

the Sait Range may be localiscd as following

(Burov et ai 1996a, b). R,P and NRP zones are

not rcvealcd. Fhe R^P/N,P boundary lies in the

lower part ol Wargal Limestone (berween rhe

tinirs 24 and 27 of Nammal Gorge section). The

NtP/RtP boundary lies* in thc upper part of

Wargal Limestone (between the units 17 and

18). The R^P/NiP boundary lies in rhe upper

part of Chhidru Formation (in the lower part of

rhe unir 72. approximately 18 m below the rop

of rhe formation), rhe structure of the upper

zone being analogous to chat of the R,P zone of

the Russian rcference section.

As miospores are concerned, the Wargal/Amb

boundary is characterised hy the disappearance

of Hamiapollenites and Corhaccites pollen grains

a.s well as by rhe first appearance ot Lueckispontes

virkkiiie Poronie & Klaus Ihere and below ail

ranges of niiospore taxa in the Sait Range are

adduced according to Balme (19"'0)]. At the

Russian Pluvforin IhUniapolUnites and Omsac-

r/Zer do not occur above thc Tatarian/Kazautan

boundary, At the same boundary appears

Lîieckisporite^ virkkiae (Fig. 2A). which ranges

then throughoLit the wholc Tatarian. Conse-

quently only K.rzanian (in any cas’e Pre-Tafarjan)

âge may be ascribed to rhe Amb Formation, the

stratigraphie gap being assumed at rhe

Watgal/Amh boundary corresponding at Icast to

the wholc early Tatarian. The présence of this

gap çan be confirmed by the data on fauna as

well. Thus according to E. Ya. Leven (pers,

comm.), thc Amb Formation corresponds by its

fauna to the Bolorian and the Wargal Limesione

to thc Midian of thc Teihys marine scale,

whcrcas thc fauna of Murgahian type was not

found at ail in the Sait Range.

It is inceresting that pollen grains of

Sulcatisporites nilsoni Balme disappear at the

292

GEODIVERSITAS • 1999 • 21 (3)

Tatarian palynology and palaeomagnetism

Russian Platform

Sait Range

>« c

O

w N

II

-C ô

IX

E O

1 y

^ O

ü X

Z)

Nefyodovskye beds

Bykovskye beds

Kalininskye beds

Pootyatinskye beds

Yurpalovskye beds

Filibskye beds

Slobodskye beds

Syryanskye beds

Belokholoonitskye beds

Ealyeanskye beds

Maximovskye beds

Chhidru

Formation]

KAZANIAN

upper assemblage

lower assemblage

Wargal Limestone

Amb Formation

Normal palaeomagnetic polarity

I I Reversai palaeomagnetic polarity

K\1 Variable palaeomagnetic polarity

Fig. 1 . — Correlating chart for the Upper Permian of Russian Plafforrrr and Sait Range.

Wargal/Amb boundary as well. These miospores

demonstrate a striking similarity with \lassic”

forms of Vcskaspora ex gr. mûgnalis (Andrcycva)

Harr (Fig. 3A) observed in the Kazanian of

Russian Platform (Meyen 6c Gomankov 1971),

and for instance rhey hâve rhe same split-like sul-

cus> whereas pollen grains of V ex gr. mupialis

frorn the Taiarian does not possess siich a sukus

(Fig. 3C). It m:iy be assumcd rhar in rhe

Kazanian and Tatarian ot ihc Rii.ssian Platform

the pollen grains dcsignatcd as V. ex gr. rnagtîdlis

belonged in lact to two diTcrcnt spccie.s bcing

rhcrcforc of a big stratigraphie importance. If is

also charactcristic ihat ihe.se dilferent types of

pollen grains vverc attrîbutcd to different species

oi Phylladodermit'. (1) the Kazanian one — to

P. meridionalis S. Mcycn and P. arberi Zalessky

(Meyen Gomankov 1971; Gomankov

Meyen 1980; Anonymous 1986); (2) the

Tatarian one - ro the .species of subgenus Aecjtm-

tomia (Anonymous 1986).

Other palynolijgical changes indicated by Balme

(1970) at the Wargal/Amb boundary (i.c. ihe

disappearance of Verrucosispontes cf. pluniverru-

catus Imgrund and Pyrarnidosporites racemosus

Balme as well as the appearance of Puncta-

tisporites cf. rninuttis Ibrahim) give nothing for

the corrélation with the Russian Platform, where

the mentioned species are absent,

rhe Chhidru/Wargal boundary finding itself on

the palaeomagnetic grounds in the lower part of

N^P zone lies therefore .somewhere near the

boundary of Vyatsk}’’ and Vishkilsky horizons. In

palynological respect it is characterised by the

disappearance of the qua^imonosaccate pollen

grains of Poîonksporhes notneus Bhatadwaj and

the appearance of the monolete spores of

f.imngat{nporitvs cdltosus Balmev l^)lypodi7Spor}les

nmtabilis Balme, Lunnlasporttes vulgétris Wilson

and pollen grains of Dcnsipollenites indicus

Bharadwaj (infraturma Monopolsacciti),

Klaimpalleriites schatihergcri (Potonie iSc Klaus)

Jansonius, Cedripitespriscus Balme (infraturma

Disacciatrileti), Potfiniesporites nticroçorpus

(Schaarschmidt) Clarke (infraturma Striatiti) and

Marmpipollenites Lriradiatus Balme 6c Hcnnelly

(infraturma Piaecolpati). Of these species L caP

losusr P mutdhilis, L. vulgitris^ D. indiens^

P microcorpub and M. triradiatus are not known

at the Russian Platform. K, schaubergeri appears

GEODIVERSITAS • 1999 • 21 (3)

293

Gomankov A. V. & Burov B. V.

Fig. 2. — Miospores from the Kazanian and Talarian of Russian Plalform Ail specimens are kept In the Geological Institule of the

Russian Academy of Sciences. Moscow. Russia. A. LueckisporUes virkkiae Polonie & Klaus, spec. 4100/100-4*213. Urzhumsky

Horizon: B, HamIapoHenites sp., spec. 4492/32b. the Kazanian, C. Cordaittna sp, (quasimonosaccate pollen grain), spec. 4388/1-3-

1-1, Vyatsky Horizon; D. Kraeuselisporiles sp.. spec. 4552/371-4-184, Vyatsky Horizon; E. Limatulasporites (= Nevôsisporites) fos-

sulatus (Balme) Helby & Foster, spec. 3774/3-X-49-22. Vyatsky Horizon; F, Osmundacidites senectus Balme, spec. 438B/1 *3-2-4 12.

Vyatsky Horizon; G, Calamospora aff. landiana Balme, spec. 4552/371-4-70, Vyatsky Horizon. Scale bar: A, B, D-G, 0.02 mm; C,

0.04 mm.

294

GEODIVERSITAS • 1999 • 21 (3)

Tatarian palynology and palaeomagnetism

Fig. 3. — Miospores from the Kazanian and Tatarian of Russian Platform. AH specimens are kept in the Geological Institute of the

Russian Academy of Sciences. Moscow, Russia. A. Vesicaspora ex gr. magnalis (Andreyeva) Hart, pollen grain with a split-like sul-

cus, spec. 3775/246b-14. the Kazanian; B, Falcisporites sp., spec. 3774/3x-a(5A). Vyatsky Horizon; C, Vesicaspora ex gr. magrialis

(Andreyeva) Hart, pollen grain without split-like sulcus, spec. 4552/371-4-47, Vyatsky Horizon; D, Cedripites priscus Balme,

spec. 4552/371-4-148. Vyatsky Horizon: E, Fimbraesporites ? sp., spec. 4552/177-2-32. Vyatsky Horizon. Scale bar; A-C. E. F,

0.02 mm; D, 0.04 mm.

trustworthy at the Russian Platform ouly in chc

Vetluzhskaya Formation of Triassic âge, i.e., ic

lias confidently anorh£r stratigraphie range.

Quasimonosaccaie pollen grains (Fig. 2C) occur

rhroughouT ihc Tatarian^ although its abundance

decreases strongly upwards and it bccomes excep-

tionally rare in the Vyatsky Horizon. As Cedri¬

pites prisctis i.s concerned, rhe very sirnilar pollen

grains (Fig. 30) are highly abundani ar the socal-

Icd oxbow-lake level in the middie of Vyatsky

Horizon, which yiclds most of palynologLcal

saïuples of Vyatsky âge. However, Cedripites is

also known in Isady locality of Vishkilsk)' âge.

Miospore assemblage from the base of Vyatsky

GEODIVERSITAS • 1999 • 21 (3)

295

Gomankov A. V. & Burov B. V.

Horizon was dcsaibed only once by Molin &

Koloda (1972) froin Kalikino locality. ’l'his

contains quasimonosaccate pollen Floriniîes Itibc'

me Samoilovitch (though as a single specinien)

and scemingly lacks pollen which conld be assi-

gned ro Cedrijutes. Oh these grouruis, one may

consider the Chhidru/Wargal boiindary lyîng

slightiy higher than the ba.sc of Vyatsky Horizon

but still lower than the oxbow-lake level, vvhere

scvcral t’orms r>'pical for the uppermost Chhidru

Formation appear (see below).

It is notewortiiy that the uppermost Chhidru

Formation is chanicteriscd by a pcculiar miospo-

re assemblage, whicli play.s an imporiant part in

the interregional ctirnelations, espccially conccr-

ning Gondvvana (Fosccr 1982; Fosicr & Joncs

1994). The exact posftion ol this assemblage in

the "Russian” scalc was impossible ro déterminé

by pure palynological means since several spccies

(Nevesisporitt's fossulatus Ruime, Kmeusclisporites

sp., Osmiimladdnes senectus Balme, CaUmospom

Imîdiami Balme, PretHcolpipollenites hfutmdtvaji

Balme, Fimhmesporites ? sp.. Falchporiies stabilis

Balme), typical fijr it, were .similar ro miosporcs

known from rhe Vyatsky Horizon (Figs ID-C,

3B, E, F), while oihers \Densoîsporît€S sp.,

Ltmdhladispora ahsoleta Balme, Cnetaceuepol-

lenites siuuosus (Balme & Hennelly) Bharadwaj,

Taeniaesporiies notntudensh LeschikJ appeared at

the Russian Platform only from the base of

Vetluzhskaya Formation (though pollen grains of

Ephedripites are known in rhe Russian Platform

Kazanian, in fan they do noi occur in the

Tatarian and appear in noticeable amounts also

in the Vetluzhskaya Formation only). Balme

(1970) did noT dcfinc ihe précisé range of this

uppermost Chhidru assemblage, but it seems

very likcly, that ihcre is a rather hig unsampled

interv'al bcns'een tbc uppermost samplcs of lower

Chhidru assemblage and the lowermost samples

of upper Chhidru assemblage. So the oxhow-lake

level, from which rhe main large amounl of paly-

nological samples of Vyatsky Florizon cornes,

may well find itscll in this unsampled incerval of

the Sale Range section. To judge from the distri¬

bution of Balmc’s samples in the Nammal Gorge,

ail samples wirh the upper assemblage corne (rom

the palaeomagnecic zone R 3 P, while oxbow-lake

level lies in the upper part of zone N 2 P (at the

boundary between rhe Bykovskye and

Netyodovskye beds). The boundary between the

upper and the lower palynological assemblages of

Chhidru Formation finds thus itself somewhere

inside the Nefyodovskyc beds.

As a resuit the stratigraphie corrélation between

the Russian Platform and the Sait Range may be

represented as shown in the Figure 1.

Acknowledgeraents

The authors want to thank Prof. H. Kerp from

Munster University (Gcrmany) for his constructi¬

ve rcmarLs on die first dralt of the paper.

RTFERENCES

Anonymous 1980. — Theory and practice of the paly^

nolodcal investigations ofPerrnian and Triassic of the

USSR. Manuscripr deposited at VINI I E Syk-

tyvkar. No. 4839-B, 192 p. [in Russian],

Bdlmc B. L. 1970. — PaJynology ul Pemiian and

l'riassic strata iri tbc Sait Range and Siirghar

Range, Wesr Pakiswn in Kummel R. &Teicherr C.

(t-ds), StYMi^apInc boundary prùhlems: Rermum and

Triasilc of West Pakistan, University of Kattsas

Prt-'.ss: 30^-4 5.5.

Bomnin V. P. (cd.) 1979. — Methods ofpalaeomu^ne-

tic uudics (if red'Colored rocks (by the exampîe of

Upper Pcrinian and Lou>et Triassic of castern areas of

Ru\Ftan Plaiform). Ka/anian Hniver.siry Press,

Kdz.an, 132 p. (in Russian).

— 1990. — l^alacomagnetic zones ofTatarian in the

basin ofVy.itka River: 7-1 ^ (in Ru.s.sian], in Aspects

of incthudic and interprétation ofgeophysical investi

gâtions. Kazan University Pres.s. Kazan.

Burov B. V.. Nurgilicv (X K. Hcllei F. 1996a. —

F^obicnis of palacomagnctic correlatioii of the

L'ppcr Pcrmiin in the stracutype and marine for¬

mations of Tethys; 93-iOO [in Russian]. in The

PWntian of Tatarian Reptddir Ka/an

Burov B. V.> Zharkriv I Y:i, Niirgaliev D. K. et al.

Î996b. — Magnetostraiigraphic eharacterisiics of

the Upper Permian of Povolzhie and Prikainie;

390-424 (in Russian), in Stratotyj>ey and rtference

seetunv ofPovolzhic and Pnkamu\ Kazan.

lorsch N. N. 1963. —■ On the straiigraphit division

und corrélation of die Tatarian sections of the cast

of the Rtissian platForin b)' the complex of Ivrho-

siratigraphic, palaeomagneric and palaeonrniogic

data: 175-211 (in Russian], in Palaeonmgneiic stra-

îigmphir tnvestigünons. Collection of papers.

‘Tîostoptekhizdat" Press, Leningrad.

Foster C. B. 1982. — Spore-pollen assemblages of the

296

GEOD»VERSITAS • 1999 • 21 (3)

Tatarian palynology and palaeomagnetism

Bowen Basin, Queensland (Australia): their rela-

tionship co rhe Permian/Triassic boundary. Review

of Palaeobotany and Palynology 36: 165-183.

Foster C. B. & Jones P. J, 1994. — Corrélation bet-

ween Australia and the type Tatarian, Russian plat-

form, evidence from palynology and Conchostraca:

a discussion. Permophiles 24: 36-43.

Gomankov A. V. 1992. — The interregional corréla¬

tion of the Tatarian and the problcm of the

Permian upper boundary. International Geological

Review ?>A\ 1015-1020.

— 1997. — The Permian (Tatarian) Flora from the

Kotelnich Vertebrate locality (Kirov Oblast).

Stratigraphy and Geological Corrélation 5: 309-318

[both Russian and English versions exist].

Gomankov A. V. & Meyen S. V. 1980. — On the

relationships of the assemblages of plant mega- and

microfossils in the Permian of Angaraland.

Paleontologichesky ZhurnalA: 11-122 [in Russian].

Haag M. & Heller F. 1991. — Late Permian to Early

Triassic magnetostratigraphy. Earth Planetary

Science Letters 10: 42-54.

Meyen S. V. & Gomankov A. V. 1971. — New data

on the systematics and the geographical distribu¬

tion of phylladoderms. Doklaay Akademii Nauk

SSSR 198: [in Russian].

Molin V. A. & Koloda N. A. 1972. — The Upper

Permian spore-pollen assemblages from the north

of the Russian Platform. “Nauka” Press, Leningrad,

76 p. [in Russian].

Suhmitted for publication on 22 April 1997;

accepted on 30 June 1998.

GEODIVERSITAS • 1999 • 21 (3)

297

Permian and Triassic exotic limestone blocks

of the Crimea

Galina V. KOTLYAR

All-Russian Geological Research Institute (VSEGEI),

Sredny pr., 74, St. Petersburg, 199106 (Russia)

vsegei @ mail.wplus.net

Aymon BAUD

Musée de Géologie, BFSH2-UNIL,

CH-1015, Lausanne (Switzerland)

aymon. baud@sst.unil. ch

Galina P. PRONINA

All-Russian Geological Research Institute (VSEGEI),

Sredny pr., 74, St. Petersburg, 199106 (Russia)

vsegei @ mail.wplus.net

Yuri D. ZAKHAROV

Far East Geological Institute, Far East Branch of Russian Academy of Sciences,

Pr. 100-letya, 159, Vladivostok-22, 690022 (Russia)

fegi@online.marine.su

Valéry Ja. VUKS

All-Russian Geological Research Institute (VSEGEI),

Sredny pr., 74, St. Petersburg, 199106 (Russia)

vsegei @ mail.wplus.net

Merlynd K. NESTELL

Department of Geology, University of Texas at Arlington.

Arlington, TX 76019 (USA)

nestell@uta.edu

Galina V. BELYAEVA

Far East Geological Institute, Far East Branch of Russian Academy of Sciences,

Pr. 100-letya, 159, Vladivostok-22, 690022, (Russia)

fegi@online.manne.su

Jean MARCOUX

Sciences Physiques de la Terre, Université Paris VII,

Tour 24/25, V étage, 2 Place Jussieu,

F-75251 Paris cedex 05 (France)

marcoux @ ipgp.jussieu.fr

GEODIVERSITAS • 1999 • '1 (3)

299

Kotlyar G. V., Baud A.. Pronina G. P., Zakharov Y. D.. Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

KEYWORDS

Upper Triassic,

Rliiielidil,

Permian,

exotic blocks»

Crimea,

foraminifers,

fusulinids,

brachiupods.

ammonoitls,

sphinctozoans.

Kotiyar G. V., Baud A,, Pronina G. P.. Zakharov Y. D., Vuks V. Ja., Neslell M. K., Belyaeva

G. V. & Marcoux J 1999. — Permian and Triassic exotic limestone blocks of the Crimea, in

Crasquln-Soleau S. & De Wever P. (eds), Peri-Tethys: stratigraphie corrélations 3.

Geodiversitas 2^ (3) : 299-323.

ABSTRACT

Exotic lime.'îconc blocks of Pemiia» and Tria.ssic âge occur in the Middle

Triassic-Middle Jurassic Crimean olbtüstiüfne complex ol the Marta and

Alma River basin.s and in the Simferopol area. Ricli assemblages of small

foraminifers, fu.sulinid.s, brachiopods, rare ammonoids» and sphinctozoans

occur in thèse blocks. Fo.s.sÜs front Permian blocks indicate ihc prcsence of

zonal as.scmblages for the BoJorian, Kubcrgandian> Murgabian> Mîdian,

D/hulHan, and Dorashamian stages. The Neoschtoagerhia ümf>lex fusullnid

zone i& cxterided upward ba.scd on the pre.seuce in our rnateriaJ of Kuber-

gandian ammonoids wlth Neoschwagerirut simplex a. Comparlson ol the

faunj from Triassic blocks to a.sscmblage.s from other régions of the Tethys

indicates chat che âge is Late Triassic Rhaecian correspondlng to the

Vandaites sturzenbaumi ammonoid zone.

MOTS CLÉS

Trias siméricur»

Kht'ticn,

Permien,

blocs exotiques,

Crimée,

foraminiftres,

fusulinides,

brachiopf.jdes,

ammonoïdes,

sphinctozoaires.

RÉSUMÉ

Les blocs exotiques calcaires du Permien et du Trias en Crimée.

Les blocs exotiques de calcaire permien.s et triasiques de la Crimée appartien¬

nent à rnnirc olistostromale d'Eskiordin (Trias mo>^n-Jura.ssique nio^'en) et

ont etc trouvés dans les bas.sins-vcr.sant des rivières de Marta, d'Alma et dans

la région du lac (réservoir) de Simferopol. Les blocs permiens contiennent

des petits foraminiferes et des fusulines ainsi que des bracliiopodes, de rares

ammonoïdes et des sphinaozoaire.s dont nous présentons rinvcnuire. La dis¬

tribution des asstniblages fossilifères couvre la fin du Pernhen inferieur

(Boloricn) ainsi que tout le Permien supérieur, du Kuhergandien au

Dorashamien. La présence conjointe d ammonoïdes et de brachiopodes d’âge

Kubetgandiai avec Neosçhwageritui simplex Ozavs'a est signalée. L’analyse des

micro- er mncrofauncs des blocs triasiques ainsi que des comparai.sons avec

les lûunes semblables d'autres régions téthysîcnncs pçnnettcni d'attribuer aux

assemblages décrits un âge rhétien.

INTRODUCTION

For this study, our team investigated Permian

and Triassic exotic limestone blocks occurring at

several localitiès in the area bettveerv Simferopol

and the Marta River Basin. Limestone samples

containing remains of several different faunal

groups were obtained. Carbonate microfacies

were studied by A. Baud. small foramintlers by

G. P. Pronina (Permian and Triassic) and V. Ja.

Vuks (Triassic), brachiopods by G. V. Kotlyar,

ammonoids by Y. D. Zakharov, sphinctozoans by

G. V. Belyaeva, and fusulinids by V. 1. Davydov

and M. K. Nestell.

HISTORY

Fokhc (1901) studied the oldest deposits then

known from the Crimea. He named the

*Taurida Beds”, and dared them as Late Triassic.

Moiseev (1939) named the Eskiorda Formation,

300

GEOOIVERSITAS • 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

a shallow-waier conglomcme (Rhaerian-Liassic)

fades présent in the northern part of the Kacha

uplifi. Muratov U 949) divided the Taurida heds

into chrcc parts: (1) a lower unir of Latc Triassic

âge; (2) a middie unir, the Eskiorda Formation;

(3) an upper unir, both of early and middie

Liassic âge. Logvinenko et al, (1961) proposed a

more detailcd subdivision ot die Taurida Sériés

and considered the lowcr part to be of Early and

Middie Triassic âge.

Srudy of outerops in the valley of the right tribu-

tary ot the Bodrak River (Dagis Ôd Shvanov

1965; Shvanov 1966) lias shown rhat the Taurida

Sériés rock ranges in age from Middie Triassic to

Early Jurassic. The most commun subdivision

scheme ot the Taurida Séries has been given in

“Geology of the USSR” (Anonymous 1969),

where the Upper Triassic, Lower Taurida and the

Liassic Upper Taurida (Eskiorda) formations

\vere proposed with two t)^es of livhotacics fur

each unit. Koronovslcy 6c Mileev (1974) conduc-

lcd rcscarch on the Eskiorda Formarion in the

Bodrak River Valley and proposed a broader

Carnian-Pleinsbachian stratigraphie range for it

On this basis, they increased rhe rank of this unit

to a Sériés and considered it as an équivalent of

the Taurida Séries rock; they aiso staced, thar the

Eskiorda Formation (or Sériés) in the Bodrak

River area represented a tectonic mélangé.

CEOLOGICALSETTING (Fig. 1)

The oldest stratigraphie unit cropping out in the

GEODIVERSlTAr « 1999 • 21 {3)

301

Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nescell M. K., Belyaeva G. V. & Marcoux J.

Crimean Mountains is ihe Taiirida flysch of

Middle Triassic to Toarcian âge (Shalimov I960,

1963). The underlying units and basement hâve

never been observed, but gcophysîcal seismic

data indicaies a ihin carbonate-<lastic unir over-

lying graniiic basement (Muraiov et ai 1984).

The laui'ida flysch is ovcrlain wiih a struciural

unconfonnicy either by Upper Jums.sic deposits

in the souih and easc of rhe Kacha uplift, or by

Lower CretaceoLis deposits in che north and

west. In some parts of the Kacha uplift, the

Taurida flysch is allochthonousiy overlain by the

Eskiorda unit. The 'l'aurida flysch makes up the

core of the Kacha uplift. Mileev et al. (1989) dis-

tinguished the Alma unit for rhe proximal flysch

in the core of the upliffv and the overlying Paril

unit for the distal flysch. The Alma unit is expo-

sed in the Belbek, Kacha. Maria. AJma. Salgir

and Bodrak River valleys le consi.stvs of predomi-

nantly gray, rhin beJded fine sand-stone -and shale

with reworked coalified plants débris.

Commonly, the Alma unit is exposed only in

river valley floors; in tbc Bodrak River Valley it is

recorded in the middle and upper parts uf slopes,

and there Is overthrusting the Patil unit. In the

Alma River (Drovyanka Village and ncar

Partizanskoc Village) and Salgir River basins, the

Alma unit contains a Carnian and lower Norian

fauna. Near Drov)'^anka Village (Alma Rivet

Basin), middle Liassic fbraminifas occiir in che

shale. Near the mouth of the Marta RiA^er,

Pliensbachian crinoids occim and in the flysch of

rhe Perropavlovsk quarry, bivalve molluslcs of

Toarcian-lower Rajocian âge bave been described.

The âge of the Alma unit is considered to be

Middle J’riassic to Bajocian. The Patil unit is

exposed only in rhe Bitdrak Rjver Valley and dif-

fers front the /\Jma unit by a grcater rhickness of

flysch couplets with mudsione dominating the

couplet.s. A middle Liassic to Aalenian fauna

occurs near Prochladnoe Village.

The Taurida fly.sch and its Aalenian to Eocene

stratigraphie cover arc separated front ihc North

Crimean covèr units (Jurassic-Eocene) by ihc

north dipping Eskiorda unit. Originally named

and intc-rpreted as the basal part of rhe Taurida

flysch by Moiseev (1932), and later by Shalimov

(I960, 1963), this unit has been recently map-

ped in detail and reinterpreted by Mileev et al.

(1989) as a composite and dismembered recronic

Lomplex. It is the best exposed witbin che

Lozovaya shear zone of the Kacha uplift (nor-

(hern pan of the core) and north of ir, but it aiso

Occurs ovenhru.si above the Taurida flysch in vhe

Bodrak and Marta River valleys. According to

the lithological and biostratigraphical contents,

thèse auihors subdivided the Eskiorda tcctonic

complex inio the Mendcr (Ladinian-Sine-

murian), D/hidair (Rajocian), Kichik (Norian),

Chenk (Middle-Upper Triassic?), Saraman (Lare

Triassic-Bajücian) and Bitak (Toarcian-

BathonianJ suhunits. The lîthology consists

mainly of fine ro coarsc terrigenous clasiics. The

rurbiditic flysch sequence characterises the lower

subunits and was probably deposited in shallow

marine conditions because coal and course sand-

stone occurs in rhe upper barantnn subunir

(.Mileev et iil. 1989). These amliors regard rhe

Eskiorda complex as équivalent in âge to the

Taurida unit.

Most uf the exotic limestone blucks occur in the

Mender subunit and some in the Saraman sub¬

unit. They are interpreted as olisdiolkhs (olist-

stronies for rhe oldcr Carboniferous to Sine-

murian part), and as tcctonic incorpoiated

blocks (mélangé) for the younger Latc Liassic-

Crctaccoiis part. Their origin is stÜl controver-

sial. Some geologists bclievc rh.it they uriginated

from the north (sourh of Scyrhian Plate margin),

vvhereas uthers consider that they werc tianspor-

ted from the suuth.

The Mender subunit (Ladinian-Sincmiirian) is

composed mainly of shalc with thin beds of fine-

grained qtiartzitic sandstone. Ir occurs in rhe

northwe.stern part of the Kacha uplift, in che

Bodrak, Aima and Salgir River valley.s. Lhe

Saraman subunit is composed of highiy mature,

Hglu gtay, ma.ssive. quarr/itic sanclstone with

beds of fine- and mediunvpebbly conglomcratc

and with rare siliy clay interbeds. it occurs on

tbc northçrn slopc and on the Southern limh of

the Kacha uplift, in the Salgir, Alma, Bodrak and

Marta River valleys. Based on macro- and micro-

fauna occurrences (Mileev et al. 1989), the

Saraman is Late Triassic-early Bajocian in âge.

302

GEODtVERSITAS • 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

HISTORY AND THE AGE

INTERPRETATION OF THE EXOTIC

BLOCKS

Fokht (1901) firsc recorded the occurrence of

Permian limesrone blocks within the Triassic-

Jurassic complex. Previous researchers hud assi-

gned chese blocks ro different siruiigraphic

horizons of the Permian System. Toumansky

(1931. 1935, 1937a, b) distinguished anirponoid,

fusulinid, and rrilobire assemblages in certain

blocks, and suidied the Permian launas from these

exotic blocks in the most detail. She considered

them ro belong to the bio.sirarigraphic ‘‘horizons”:

Bodrakian, Soramanian, Burnian, and Martian.

Initially» she presiimed that the Soramanian

assemblage was similar ro thaï found in the

Gaptank Formation in West ’lexas and to be of

Late Carboniferous âge [Uddenitiîs zone).

Subsequeiuly, ‘Foumanslcy (1941) concluded that

the limestonc with this animonoid assemblage

corresponded to ihe lowcr part of the Permian

Leonard Formation in West Texas ol Norih

America, rhe lowcr paît of the Ritauni Formation

on ’Fimor Island, and rhe upper part ot Buzterc

beds in the Sourheastern l’amirs. In hcr srudy of

Permian aminonoids of the Central Pamirs,

Toumansky (1963) correlated the Burnian and

Martian ammonoid assemblages of the Crimea

with the Kubergandian assernblage from the

Pamirs. According to Bogoslovskaya (1984), the

Burnian assemblage is similar to the ammonoid

assemblage in the Kuherganda Formation of the

Pamirs. and is Roadian in âge. I he so-callcd

“Martian (Martovsky or Martinsky)'' assemblage

is considered to be Wordian.

The Lare Ifiassic âge of certain lîmestone block

is mainly derived from occurrences of Anisian

and Norian-Rliaetian brachiopods (Dagis 1963;

Dagis & Shvanov 1965).

CRIMEA-PONTIDES (NORTHERN

TURKEY) TENTATIVE CORRELATIONS

(FIGS 2,3)

The Crimean Mountains and the central Pon-

lides (Turkeyj represent the conjugate rift margin

of the Western Black Sea oceanic basin (Fig. 3).

Fig. 2. — Early Jurassic reconstruction, following openîng of

Kùre/Taurida basins; schematic and not scale (simplified and

modified from Banks 1997).

Prior ro the opening ot the Western Black Sea

oceanic basin initiared in Barremian-Aptian rime

and completcd in Cenomanian time (Gorur

1988). Southern Crimea atid central Pontides

occupied neighbouring po.sitions (Fig. 2, sec also

reconstruction schemes recenily proposed hy

Banks and Robinson in Banks 1997L

In the Crimea (this paperl as well as in the central

Pontides (Aydin et ai 1986; Yilmâz et al. 1997),

there are occurrences of flyschoids .successions. In

the Crimean Mountains and lhe central Pontides,

the oldest rocks exposed are à scqiiencc of basinal

tufbidiric mudstones and .siltstones of similar age

(Triassic-Early Jurassic). These formations were

disrupted during the Cimmerjan orogenesis at

the end of the Middle jurassic (Sengür 1984).

As was proposed before (Marcoicx 8e Baud 1996;

Marcoux et al. 1993) the équivalent of rhe

“Taurida flysch” from the Crimea would corres¬

pond tü the Küre séries, of the Akgol Formation

(Aydin et ai 1986; Yilmaz et al. 1997) from die

central Pontides. This hypoihcsis was proposed

again recently (Robinson ôc Kerusov 1997).

At the moment, only Triassic exotic blocks (olisto-

liths) hâve been described within rhe Küre/

Akgol sériés, for instance Hallstatt fades Ümes-

tones of late Anisian and Ladinian (Onder 1990;

L. Krystyn, pets. comm. 1992). Future detail

GEODIVERSITAS • 1999 • 21 (3)

303

Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

Fig. 3. — Schematic structural cross section of the eastern part of the western Black sea from northern Turkey (Central Pontldes) to

Crimea Mountains (South Ukraine) (simplifiée! and modified from Banks 1997).

investigations mighr also demonstrare the occur¬

rence of Late Palaeo7x>ic blocks, similar in âge to

those from the Crimea described in this paper.

PERMIAN EXOTIC BLOCKS

Permian exoüc blocks were studied in the Marta

and Alma River basins and in the Simferopol

area. Corrélation of these blocks and locations of

fossils are shown in Table 1.

Marta Rivfr Basin

In lime.stone exposed on the .slopes of Kichkhi-

Burnu Mountain in ihc Marta River Basin,

Toumansky (1941) recorded two "horizons with

fauna” (fusulinids, ammonoids, trilobites) which

she called Burnian and Martian. She correlated

the Burnian “horizon" with the upper part of the

Leonardian, and the Martian “horizon’' with the

Wordian in later stiidies, it was ascertained that

these so-called “horizons" were noc valid, and the

assemblages were correlated to rhe Permian

Murgabian» Darvazian and Pamirian stages

(Einor & Vdovenko 1959; Licharesv 1966),

In the Marta River Basin, rhe largest Permian

block (65 X 35 X 15 m) is lotated on the right

flank of one of the right rributaries of rhe Marta

River, 5 km upsrream from the Verkhorechye

Village (Loc. 110; Eigs 4A, 5). Elerc light gray

and pinkish-gray noa bedded algaEhrsuHnid

(reefogenic?) limestone forms Kichkhi-Burnu

Mountain. Several smaller blocks located near-

by, also contain abundant and diverse foramini-

fers, brachiopods, trilobites, gastropods, and

ammonoids. Some of these blocks contain dis¬

tinct lithologies separatcJ by b recela zones and

contain different fossiJ remains. Peripheral pans

display dasiic rexrurcs (rounded and semiroun-

ded fragments of gray boundstone with light-

colored carbonate ccmcni), as wcll as micritic

limesione of a pinki.sh or beige tint. The north-

western margin ol the main block appear.s to

contain the oldest sédiments.

Loc. îîOharnple 1

The limestone of this samplc is a wcll-sorccd ske-

Icral grainstonc containing calcarcous algae, fora-

minifets, gasiropods, calcarcous sponges and

btachiopod fragments. Ir is tnterprered as being

deposiied in a high energy, shallow marine

pa I aeoen vi ronme n t.

Small foraminifers, collosu Rcltlinger,

Mendipsid conili (Nguyen Duc l ien), Endnthyra

sp,.^, CUmacamniioo ocih'uliooides I a nge,

Deckerelln sp. 2, Tetrotaxis sp., GlobivolvuUna

grncca Reichel, Paliieotextularm pivg^uoemis Lin,

P. sp.(= P. hngnrprata Lipina />; Zlieng 1986),

Pachyphloto sphnertiln Sosnina, Loogclla sp.,

Neodisens N. m 'tUflaides M.-Maday.

Fusulinids. ParafiisuUna vinogradaid Leven,

cf P. mnltiseptata (Schelwien), P^ afl. P. naka-

migtivai Morikawa Ôd Horiguchl, P. ait. P. yxm-

ruinlca Sheng. P. enUsispira Leven,

P. munitkekovi l.even, P. undulato Chen,

Annenhia asidtiut Leven, A. kannav (Kochansky-

Devide & Ramovs), A. salgirica A. M.-Maday,

304

GEODIVERSITAS • 1999 • 21 (3)

Permian and Trîassic exotic blocks of the Crimea

Tethyan

scale

ieven 1980. 1996

Kotlyar & Pronina

1995

Aasem-

biages

Toumansky

1931. 1941.

1963

Marta River Basin

Alma River Basin

Simferopol area

110

129

112

122

WTül

111

B

E

B

E

B

m

g

B

D

B

E

B

E

B

Dorashamian

■

1

■

i

■

1

■

1

■

1

Dzhutfian

■

e

g

B

1

Yabeina

J

■

1

■

1

■

B

1

Neo-

schwagerina

margaritae

Martian

1

B

1

i

B

i

1

Neo-

scOwagerina

craticulifera

1

Kuhergandiari

Nec-

schwaqerina

simplex

Praesumalrina

Bumian

SF

F

Br

A

ST

gj

1

SF

F

Br

1

SF

F

Br

1

Cancellina

cutalensis

B

1

B

1

r

1

B

1

y

Misellina

claudiae

Soramanian

1

B

1

Table 1. — Distribution of fossil localitles and corrélation of Permian exotic blocks in the Crimea. SF, small foraminifers; F, fusulinids;

A. ammonoids; Br, brachiopods; ST. sphinctozoans.

A. sphaera (Oz;iw3), Cancellina cl. C primigena

Haydcn, C. prueneoschwagerinoides Lcven,

C, phlonghprabeusis Toriyama àc Kanmera,

Neoschivageririit siynplex tenxiis Toriyama &

Kan niera. N. aff. N. simplex Ozawa,

Praesumntrina schellwtertî (Deprat).

Sphîactozoans. Colospongia sp., Crymocoelia

zacharovi Bclyacva, Vesicotubulnria prima

Bclyaeva, Paradenîngeria martaensis Belyacva,

Süllasia sp.

Brachiopods. Avosarinn sp., Rugaria moterigraaffi

( B ro i I i ), Vrushtenia mu rina ( G ra n r),

Neaplicatijera sp., Comuquia cf. C. modesta

Grant. Marginif'era carniolica (Scbeliwien),

TramennaPia gratma (Wuagen). Bihtina aawtba

(Waierhouse ik l'iyasin), Litioproductus aff.

L. kaseti Grant, Compressoproductus mongoikus

(Waagen), Ogbirna dzhngrensis Sarytchevat

Vncmunelhym siculus (Gemmellaro), Auomaloria

gtomcrosa Grant, Pcrmopbricodotbyris caroli

(Gemmellaro), Maniuia ceres (Gemmellaro).

Ammonoids. Propirtacoceras sp., Prostacheoceras

tauricum (Toumansky), Cardiclla kussica

(Toumansky). Apparently, the ammonoids des-

cnbcd by Toumansky (1931) also originated

from Locality 110/1. These were identified as

Parapronorites konincki Gemmellaro, Propina-

coceras galilaei Gemmellaro, PP soramanse

Toumansky, P?. rzAwewre Toumansky, Medlicottuû

volgi Toumansky, Thalassoeeras kurpinskyi

Toumansky, Agathiceras sxiessi Gemmellaro,

A. planum doumansky, A, hodraki doumansky,

A. katscht Toumansky, A. bachui Toumansky,

A. anceps Gemmellaro. Cardiella kussiat

(Toumansky). Neocrimites {Sosiocrimites) hiassa-

lensis Toumansky, Arivoceras ail. A. etnifer

(Gemmellaro), Palerrnites cf-. P. distefatiui

(Gemmellaro), Prostacheuceras muhidentattun

(Toumansky), P. huruense (Toumansky),

Staclmceras mediterraneum crimeuse Toamanskyr

S. andrussoioi îbumansky, S. bosei doumansky.

S, borissinki ToiimanskV) S. vogii doumansky,

5. cf S tictzei Gemmellaro, 5. tepense

Toumansky, Tauroceras wmvieri (Toumansky),

T. serobicNlatifs martonis (doumansky). Para'

celtites boefori sopbiensis Toumansky.

Trilobites and single fragments of isolated tctra-

corals belonging to the family Plerophyllidae

(most likely to the généra Pentaphylluni and

Ufimia) where noted by Toumansky (1935),

whü also Indicated that small bivalves and gastro-

pods were also présent at this locality.

GEODIVERSITAS • 1999 • 21 (3)

305

Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. &c Marcoux J.

Fig. 4. — A, map of the study area with localities of the Permian and Triasslc exotic blocks: B, location of Permian exotic blocks In

the Alma River Basin- C. location of the upper Midian (Capitanian) and Dzhulfian limestone blocks on the right side of Izvestnyakovy

Creek In the Alma River Basin. Site is on the left side of a trail going up ftom the Alma Resen/oir and is in dense foresl.

Loc. llOhample 4

This sample, locaced at the northern margin of

the block (Fig. ‘î), consists of medium sorted ske-

letal grainstonc, with Lithocùdiunu coaied grains,

intraclasts, forâminifers, gastropods and other

shell frâgnu'nis.

Small forâminifers. Valneolextularia sp.,

DeckerelUt sp. 2^ CLimacatynnivn tmlvuUnQides

Lange, l\îliie(fspiroplecuim>nmti ex gr. P. conspccta

Reitlinger, Polytaxh sp.> Orthovertella sp.,

Neodisem N. milldoides A. M.-Maday.

Fusulinids. MinojapanelLi .sp., Pûmjvsidina cinc-

ta Reichel, P, cl, P. erratoseptatn Kling, P. emssi-

septata Leven, P. cf. P. undulata Chen,

P. japonica (Guembel), P. nakamigawai

Morikawa & Horiguchi, Psetidofusulina aff.

P. hisamatsui Morikawa.

Loc. llQharnple 2

This sample is a reefoidal boundstone with

encrusted skeletal éléments and cavities fîlled

with biosiltite.

Loc. llOhcLmple 3

This sample is from a small (about 0.7 m across)

block. l'he limestone consists of a well-sorted

skeletal grainstone with intraclasts and with coa-

ced grains formed from calcareou.9 sponges. lora-

minifers, gastropods, brachiopod spines and

bryoïoâns.

Fusulinids. Ncofusulina funnda (Ozawa),

yangehrenia cf Y. compressa (Ozawa), Para-

fusulina cincta RcichcL Armenma sphaera

(Ozawa). Neosthwagerimi simplex Ozawa, N, sim¬

plex tenais 'loriyama Kanmera, Praesumatrina

neoscfrwagenmHdes ( r3e p rar)-

Brachiopods. Acostirina sp., NeopUcatifera sp.,

Trayisennatia gt-atiosa (WaagenJ, IJncinunellina cf.

U, anior (Gemmellaro).

Loc. llOhampUs 6, 7

These samples consist of a poorly sorted calciru-

dite, with biocalcarenite packstone pebbles, frag¬

ments of oncoidal trust, calcareous algac,

forâminifers, gastropods, bryo/oans, bracliiopods

and sheil fragments. Internai fissures are filled

with fine-grained calcarenite. The environment

of déposition is intcrprcccd as marine fbrcrccf.

Small forâminifers. Tuberitina collosa Reitlinger,

Mendipsia conili (Nguyen Duc Tien), M. sp.,

306

GEODIVERSITAS • 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

Fig. 5. — Location of collection sites at the Kichkhi-Burnu

Permian limestone blocks in tho Maria River Basin (Loc. 110).

Matrix consistfi ol the Soraman sandstone (Pllensbachian)

Lasiodiscus 'ip. 1. Palaeottxtul^ria sp. (= P. long!-

septata Lipin.i in Zheng 1986), Deckerella media

permiana Wang, Palaeospivopkciarnmina ex gr.

P. conspecîa Rcrirlingef, Tetrataxis }naxima

Schellwien, T. sp., Globivalvulina graeai RcichcJ,

Calcivertella sp., Orthiweriella sp.> Ncodiscus aiV.

N. milliloides h. M.-Maday, Paçhyphhia sphami-

la Sosninai A ovata (Lange), Nodoinvolutaria

jiiinica Han.

Fusulinids. Ncoschwagerina simplex Ozawa,

Cancellina sp., Pracstimatrina rossica A. M.-

Maday, NeoftmilinclLi nana A. M.-Maday.

Loc. îlO/samplc 5

This sample consists of a poorly sonect biocald-

rudite, wirh calcareous algae, foraminifers, aggre-

gates and encrusiing laminated microbial mats

ISphearacodium).

Small foraminîfers. Globïvalvulina sp., Palaeo-

textîdariida indct.

Fusulînîds. Yangchienia baydeni Thompson,

y. roÀ/c’r/Thompson, Parajusulina sapperi (Staff*),

P. japonica (Gumbd), P. nakarnigauuti Morikawa

& Horigucbi, PseudofusuUna cf. P. iienoensis

Kobayashi, Arnunina sarabtiriensh To.r)^3ma fit

Kanmera, Verbeekina verbeeki (Geinitz), CanceP

Ima iephnpttti Kanmera & Totiyama, Neoschwa-

gerina colaniae (3zawa, N. ex gi. N. pinguis

Skinner, N. crativulifera (Schwager), Pseudo-

doliolhia ozawai Yabe & Hau/awa, and Prae-

sumatrina grandis Leven.

Loc. llOkample W

At tliis locality ncar ihe eastcrn side of the block,

the talus is composcd of slightly marly gray

limestone yielding remains of brachiopods,

ammonoids atid irilobites.

Brachiopods. Entelrtes cf, E. sublacvis Waagcn,

E. geniculatîis Lichârew, Linoproductus aff.

L. kttseti Grant, üghinia dzhagrensiy Sarytdteva.

Sphinctoxoans. Colospongia sp., Cyymocoelia

zacharovi Belyaeva, Vesicotubulatia prima

Belyaeva, Paradeningeria martaensis Belyaeva,

Sollasia^. sp.

Ammonoids. Propinacoceras sp., Prostachcoceras

tanriciim (Toumansky), Cardiella kussica

(Toumansky).

Loc. }l0/samplt‘s9,20. 21

Sûutheast of the main block ai this locality there

is a sinallcr block cxposcd along the Glybovy

Crcck (hig. 5). The lithology of the block

consists of a poorly sorted calciruditc to calcare-

nicc packstonc, with rcefboundsconc clasts, frag¬

ments of oncoidal crusc, calcareous algae,

foraminîfers, crinoids, bryozoans, brachiopods

and shell fragments. Internai fissures are filled

with micrire. This lithology and fàuna indicate a

marine forereef palaeoenvironmcni.

Small foraminîfers- Tuberitinn coUosa Rcitlingcr,

Atjussclla sp., Mendipsia sp., Dagrnarita sp.,

Glohivalvulina sp., Neodiscus aff N. milliloidcs

A. M.'Maday.

Fusulinids. Neo^fusulinella lantenohi Deprat,

N. saralnmensE Toriyama, Kanmera &: fngevat,

TV, nana A. M -Maday, Armaüna salgirica

A. M.^Maclay, Armentnn prisen Toriyama &

Kanmera, Verbeekina sp-, Praesumatrina neosvb-

wagerinoides (Deprar), Cancellina prtmigena

Haydcn, C. samburiensh Kanmera &c Toriyama,

C. (Sbengella) cllipvica Yang, Neoscbwagerina sim-

plex Ozawa, Parafusulina granumavenae

(Roemer), P. aff. P. tebuenkovi Leven, P. aff

P. yabei Hanzawa, Chiisenella Engi Sheng.

Brachiopods. Neoplicattfera sp., Marginifera car-

nioUca (Schellwien), Rostranteris inflatum

(Gemmellaro).

Limestone of the main body of ihe Marta block

(Loc. 110) is characterised by cwo assemblages of

fusulinids: an assemblage of the Ncoschwagerina

GEODIVERSITAS • 1999 • 21 (3)

307

Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

simplex zont (Loc. 110/1, 3, 4. 9, 20, 21) and

the assemblage of the Neoschwa^erinu cnuiaitife-

ra zone (L.oc. 110/5). According to Bogoslov-

skaya (1984), two ammonoid assemblages arc

rccorded in the Marta block: (l) an oldcr one uf

Roadian (Burnian) âge; (2) a younger one of

Wordiaa (Martian) âge. Zakharov (this wurk)

found only ihe Roadian ammonoid assemblage

(Loc. 100/1, 10). Simll foraniinders (Loc. 110/

1, 2, 4, 6> 7, 9, 20, 21) axe Roadian or Kuber-

gandian. The brachiopod assemblage (Loc. 110/

T3, 9, 10, 21), is most probably also of a samc

âge. The Roadian ammonoids, sniall tbraminifers

and brachiopods occur with fusulinids of the

Neoschwugerina simplex zone.

Alma Rivek Basin

Exotic blocks and pebbics of Permian limestonc

within Eskiofda Scrie are also rccorded in the

Alma River Basin, in the areas of the Bodrak

River, and Izvesrny.Tkovy and Niknik creeks

(Fig. 4B).

Loc. 129

Many blocks of different âges hâve been observed

in the Bodrak River area. Here vve are describing

a new Permian block (Loc. 129) discovered in

1996 (Fig. 4A). ’Fhis isolatcd block is locared on

the right bank of the river near Trudolubovka

Village.

The block from which this samplc (Loc. 129)

was obtaincd Ls about 0.5 ni across. It is a biocal-

ciruditc with carbonare-quarrziric cernent and

rounded millimétré ro centimètre sized pebble

clasts of lime rnudsione. calcareou.s sponges,

radiolarian lime mudstonc, cotais, and foramini-

fers. There are also .single ooids in ihe mairix.

This texture indicates an exposure ol a Permian

sequcnce reworked in a high-energy shallow plat-

form marine environment with quarr/.itic terrige-

nous in pur.

Small foraminifers. Lasunliscus tennis Reichel,

Globivûlvulina sp., Agathammina sp., Nodosaria

caucasien mirabilis K. M.-Maclay, Pachyphloia

cukurkoyi Civrieux & Dessauvagie.

Loc. 122

On the right bank of Izvestnyakovy Creek, about

350 m upstream from its mouth, several blocks

(Luc. 122) of gray and light gray crinoid limcsto-

ne (about 15 X 6 m) werc discovered (Fig. 4C).

They contain remains of algae, and sphincto-

zoans — Colospongia cl. C. salinaria (Waagcn &

Wentzel), Vesicotubnlaria prima Belyaeva.

Loc. I22a

This sample consists of a clast-supportcd calciru-

diie with eiicrustcd microbial cléments and bio-

calcarenitc with foraminifers. Diagenesis showing

radiaxal cernent and internai filled cavities of

silty mudstone indicates an upper shoreface

marine dcpositional environment.

Small foraminifers. Pornberitina reiiHiigerae

A. M.-Maclay, Mendipsia conili (Nguyen Duc

Tien), Lasiodiscus Tennis Rcichcl, Lasionvehus sp.,

Postendothyra sp., CÂimacammina sp., Palaeo-

spiroplectammina sp., Dagmarita sp., and

Geinitzina sp.

Lac ]22b

This sarnpie is a cla.st-siipported calcirudite from

a pcrircetal environment containing foraminifers,

calcareous aJgae. bryozoans and brachiopods.

Small foraminifers. Eotuheritinn reitlingerae

A. M.-Macby, Tuberitinu collnsa Rcitlingcr,

Lasiodiscus tennis Reichcl, Neoendothyrn sp.,

Postendothyra sp., Palaeoiexinlaria sp. 3,

CAimacammina sp. 1, C. verbeeki Lange, C ex gr.

C Viitvulinoidc^ Lange, Deckerella sp., Palaeo-

spiroplectammina sp., Tetrataxis sp., Abadehella

sp., Agathammina sp., Multidiscm sp., Nodosaria

sagitta K. M.'Maday, N. pLmocamerata Sosnina,

IjtngdLt perfonna langei C'ivrieux & De.ssauvagie,

Geinitzina aiaxensis G. BroninUi G. spandeli

Tchcrdynzcv». G, uralka simplex Iv. M.-Maclay,

Pachyphloia rohmta K, M.-Maclay, Pseudotristix

solida Reitlinger, Ichtyolaria primitiva Civrieux &

Dessauvagie, and Hubeirobuloides sp.

Fusulinids. Cüdonojusu'lla cf. C. erki Rauscr, and

Reichelina changhsingvnsts Sheng &: Chang.

Loc. 122e

This sample is a reefal houndstonc with a

Microcodium type of encruscation and radiaxal

cernent.

Small foraminifers. Lasiodiscus minor Reichel,

Neoendothyra sp.y Globivalvulina sp., Hemigordius

sp-, and Geinitzina sp.

308

GEODIVERSITAS • 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

Fusulînids. Yangchienin cf. Y. thompsoni Skinner

& Wilde, Chusenella sp., Nankinella cf. N. ovata

A. M.-Maday, and Reichelina crihroseptata Erk.

Lac. Î22d

This samplc is a calciruditc ol poorly sorted bro-

ken clasts in a biodastic Jnatrix.

Small foramioifers. Mendipsia conili (Nguyen

Duc Tien), Tuberitina collosa Rcîtlinger,

Lnsiodiscus rninor Rcichcl, Deckerella sp.,

Endoteba controversft Vachard Ei Razgallah,

Dagmarhd sp., GlobivalvuUna cyprïat ReichcJ,

G. vonderschmitti Reidiel, Pasiendothyra noviz-

kiana (Sosnina), P. micula (Sosnina), Neoaido-

thyra ornata Sosnina, Tetrataxh conictx

Scheliwien, AhadebelLl sp., Orthovertellû sphaeri-

ca G. Pronina, Bdisttlina pulchra Rcitlinger,

Sphairioniû (Pseudosplmirionia) lienit (i. Pronina,

Nodosaria cf N. pdrtisauii Sosnina, Pseudo-

LtngelLi gertuitmensîs G. Pronina. P. filiamformn

G. Pronina, P. dzhagadzurensis G. Pronina,

Rectoglandulina gerkei Sosnina. Pachyphloia rtmii-

Id Sosnina, P. cukurkoyi Civricux & Dessauvagie,

P. minutissima Sosnina, Partisania sp. 1, and

Rcctostipxdina .sp.

Fusulinids, Raxtserella sp., Reichelina cribrosepta-

ta Erk, Danbarula ruina Kochansky-Devide &

Ramovs, Lantchichites cf niinirnus Chen,

CodonofusielLt cf C. kaeichowrnsis Sheng,

Yangchienia thornpsoni Skinner & Wilde,

Chusenella cf Ch. splendens (Skinner)^ Ch. cf

Ch. cyri (Skinner)- Kahlerina pachytheca

Kochansky-Dévide & Ramovs, Verheekina cf

V. furnishi Skinner & Wilde, Neoschwagerina

schuberti Kochansky-Devide, TV. haydeni

Dutkevich Khabakov, N. kojensis Tomnansky.

Loc. 113

On the lefc bank of Izvcstnyakovy Creek about

550 m upstream Rom the mouth (Fig. 2B), vve

foLind a small block (40 cm X 80 cm) of gray

microcrystalline limestone.

Loc. 113 is a calcirudite wiih ooid grainstone

and wirh biowackestonc clasts. The skcletal clé¬

ments consist of sponges, shell fragments and

foraminifers.

Small foraminifers. Deckerella aff. D. elegans

Morozova, Climacammina valvulinoides Lange,

Endoteba controversa Vachard & Razgallah,

Postendothyrn gunngxiemis (l-in), Abadehelln cf

A. conifnnnis Okimura & Ishii, Globivalvulina

graeca Reichel, G', vonderschmitti Reichef

Agathammina ex gr. A, rosella G. Pronina,

Mididla zanineîtiae (iAltincr), Multidlscus .sp. 1,

A/, sp. Z, Calcitornella sp. 2, Nodosaria cf N.glo-

bocutaris Sosnina, N. dorachamensis G. Pronina,

N. mirabilis çaucaska K. M.-Maday, Pachyphloia

ex gr. P. pigmohesa Wang, P. paraovata K. M.-

Maday, A angtdata K. M.-Maday, Pseudotristix

sp., Geinitzina sp , Colanhila ex gr. C. minima

Wang, and C. ex gr. C lepidn Wang.

Fusulinids. MinojapayxelhP sp., Pscudodunbarula

minirna (Sheng bc Chang), P. aff P. arpaensis

Chedija, Paradunharula z/rtZ/yf Skinner, and

Reichelina changhsingensis Sheng bz Chang.

Loc. 112

On the opposite side of the Alma River Valley

(Fig. 4B) along Niknik Creek (Loc. 112), gray

fme-grained sandstonc crops eut which conrains

an isolatcd block (about 3 m across) of gray brec-

ciated limc.stone wirh ‘Toulder” jointing wirh

ammonoid rcmains.

Ammonoids. Propmacoceras sp., P. sp. inder.,

Agathkeras sp., A. sp. indet., Cardiella kussica

(Toumansky), Adrianitesl sp., Tauroceras sp.,

Paraceltites'i sp. This assemblage is Roadian or

Kubergandian agc.

SiMJ-EROPOL AREA

The geology of the Simfcropol area is de.scribed

in Moiseev^ (1937)* During this study the cxotic

blocks were examined ar Cape Dzhien-Safu, near

Marjino Village, and east of Simleropol

Réservoir (Fig. 6A).

Loc. 111

On rhe western end of Cape Dzhicn-Safu ai

Simferopol Réservoir (Loc. III) thcrc is a large,

northwesc trending, clongace block of limestone

(Fig. 6). Ir is about 180 m along ihe long axis.

On the marginal parts, it is composed of black

and dark gray microcrystalline limestone which

is massive, fissured, and contains pocket.s of

accumulations of fusulinid shells (Loc. 111/1).

Loc. 111/sample 1

Fusulînids. Parafusulina crassispira Leven, P. aff

GEODIVERSITAS • 1999 • 21 (3)

309

Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

Fig. 6. — A. location of the Permian limestone block (Cape

Dzhien-Safu) and pebbles (Marjino Village) near lhe Simteropol

Réservoir; B. collection sites at the lower Midian (Wordian)

limestone block (Loc. 111) in the western part of Cape Dihien-

Safu.

P. dronovi Lcvcn, Chusendh sp., Eapolydkxodina

aff. E. zidumurtemis Lcven, Armenina utlgirica

A. M.-Maday, Verb^ek/na verbeeki (Geinitz).

Cancellim pracneoichwagerïmïdes. Levcn, C. enta-

lensis Leven, C. tenuitesta Kanmera, Neo-

schwagenna simplex Ozawa, Pmesumntrina rossica

A. M.-Maday, PseudodolioUria ozawai Yabe &

Hanzawa. The âge is Kubergandian.

Loc. lîîhample?

Small foramînifers. Tuberitina collosa Reitlinger,

Mendipsia conili (Nguyen Duc Tien),

Cdobivalvulinn vonderschmltti Rcichd, Postendo-

tbym sp., letrataxis ex gr. T. iinea Ozawa, and

Abadehelbi sp.

Fusulinids. Sumatrina sp„ Rauserclk sp., and

Cancellimi cf. C primigena (Hayden), The âge is

early Midian.

Loc. ] I l/samples 2, 3, 3a

These samplcs consist of dense biocalcarenite

packstonc witb foraminifers and intraclasts, and

ate interprered to be depo.sitcd in a marine inner

shcU environment.

Small loraminifers. Eotuheritina reitlingerae

A. M.-Maday, luheritina collosa Reitlinger,

Mendipsia conili (Nguyen Duc Tien), M. sp.,

Telrataxis maxirna SchclUvicn, T. scita Lin,

T. linca Ozawa, Abadehella hunanensis (l.in),

Globivalvulina vonderschmitti Reichel, G. aff.

G. pemiiana Tcherdynzev, Postendothyra noviz-

kiana (Sosniiia), P. ussurica (Sosnina), Calci-

vericlla sp,.

Fusulinîds. Afghanella cf. A. sumatrinaeformis

(Gubler), Sumatrina rossica A. M.-Maday,

Kahlerhui sp., and Ranserella sp. The âge is early

Midian.

Loc. 123

At Marjino Village (Loc. 123), several small

blocks of fossiliferoiLS limestone were found (near

the foundation of a house under construction

and not available for future study) among coarse-

grained Lias-sic tuRogcnic sandstonc and conglo-

inerate (l’ig. 6A). These samples consist of

calcaccous quartziric sandstone with foraminifers.

Loc. 123/sample 2

Fusolinids. Chusenella deprati Ozawa, N. cf

N. kojensis Toumansky, N. pinguis Skintier,

M aff. N. rninaensis Deprat, CoUtnià aff C. aka~

sakensis (Morikawa & Suzuki), Yahtina opirna

Sldnncr, Y. urcbaica Dutkevlch, K cf Y, glohosa

Yabe, Y. orbiculata Chedîja. K inonyei Deprat,

and Neoschwugcrina craticidifera (Schwager). TKis

assemblage is of late Midian âge.

Loc. 123/sample3

Northwards, at the margin of the village on the

hill slope, we found a separate limestone block

measuring about 0.5 X 0.5 m (Fig. 6A).

310

GEODIVERSITAS • 1999 • 21 (3)

Permian and Triassîc exotic blocks of the Crimea

Fusulinids. Nfoftisulipjellu sitraburiensis

Toriyama, Kanmera & Ingcvdt, Misellina aliciae

(Deprar), M. otakiensts (Huzimoio), A/, aft.

M. ternïmi (Deprat), and M. cLtudiue (Dcprac).

This assemblage is of Bolorian âge.

Loc. 125

Along the eastern side of Simferopol Réservoir

(Loc. 125), two limesrone blocks were found on

the watershed (Fig, 2A). 'Fhe First onc is about

0.8 X 0.5 m. and the second onc about 0.5 X

0.5 m. Based of the fusulinid data, the âge of

limesrone from locaJity 125 is Kubergandian.

Loc. 125fsmnplc l

This block îs composed of dark gray, almost

black microcrystalline limescone. The micro-

faciès consiscs of a mud-siipporced biocalcarenice

rich in foraminifers,

Sntall foraminifers. Tubenthm collosa Reirlinger,

AtjusseUa gtmidh G. Pronina, Diplosphaerim aff

D. waljavkini (Mikhalov), Mtndipsia sp-,

Endothyra saucra (Lin), GlohivalvuUna graeca

Reichel, Pnlffeospiropkcî^mmina ex gr P. ronspec-

ta Reitlinger, Calcitornella sp. 1, Cnlcth'ertelLi sp.,

Agathammina sp., Neodiscui aff. N. milliloides

A. M.-Maday, Nodosarîa sp. (= N. longissirnn

Suleimanov in Zheng 1986), Pachyphloia ovatn

(Lange).

Fusuliaîds. Yangchienia cf. Y. compressa

(Ozawa), Diinbcirulcû cf. D. vascadensh

(Thompson, Wheclcr &C Danner), Chnsenella

schrvagerintieformis Sheng, Armenina afl A. prisca

Toriyama Kanmcra, A. sphaera (Ozawa),

A. saraburiensis Toriyama fie Kanmcra, Misellina

ovalis (Deprat), M. aff M. confiagaspira Leven,

M. termieri pamirensis (DutktMch), Al. ctandiae

(Deprat), Canctllina primigena (Ha\ den), C. aff.

C. praeneoschwagerinoides Levenj C. dutkevitchi

Leven, C. catalensis Leven, C. paynirka Leven,

and Praesumatrina nmchwagerinoides (Deprat).

Loc. 125lsampk 2

Fusulinids. Yangchienia sp., Sichotenella} sp.,

Neofiisulinella lantawisi Deprat, DunbaruUü sp.,

Chusenella chihsiaams (Lee), Armenina asiatica

Leven, CanceUina dutkevitchi Leven, C cutalensis

Leven, C. zarodcmis Sosnina, C sphaera A. M.-

Maclay, C verae (Toumansky), C. aff C nippo-

nica (Ozawa), Neoschwagerina simplex tenais

dbriyania & Kanmera, and Praesumatrina neo-

schwagerinoides (Deprat).

ANAI.YSîÿOr PMINAI. AS.SFMBLAGES

Ammonoids

The Early Permian (probably, Bolorian) and the

Lace Permian (Kubergandian or Roadian)

(Loc. 110/Il 10) âge of the CWmca limestone

blocks is cstablished based on the ammonoid

data. As was correctiy noted by Toumansky

(1931, 1937a, 1963), clic oldest ammonoids of

the Crimea blocks are forms of the Soranianian

assemblage, thaï she discovered in one of dark

gray limestone blocks of Kichik-Soraman

Mountain. Tins assemblage i-s tomprised of

représentatives of Propinacoceras. Skanites,

Agathkeras, Gastrwçerataçeae, Almites}, Cardiella,

and Crhnites. The Early Permian âge of the

assemblage is conllrmed by the presence of repre-

senvacives of Crimites-C, gemmeUarot, C, haniclï,

C sp indet., and apparently Almites-

/!.? pigneum. Species of the genus Cardklta are

pot found in deposits older than Bolorian.

Therefore, it would he rnost logical to a.ssume

that the limestone blocks containing these

ammonoids bclong to the Bolorian stage of the

Lower Permian.

The geiietic composition of ammonoids Irom

limestone blocks on the right side of one of the

tributarics ol the Marta Rivet in the area of

Kichkhi-Burnu Mountain [ParapronoriieSy

Propinacoceras, Aledlicottiat.. Thalassocerasy

Agathkeras, Cardiella, Neocrimites (Snsiocrimites)^

Aricoceras, Patermites., Prostiîcheoccnis., Taurocerns,

and Paraceltites] (with respect to our new évi¬

dence) is almost identical to the Kubergandian

assemblage, thar confinn.s the relevant conclu¬

sion initially drawn by 'foumansky (1963).

Noting the similariry of this assemblage with

ammonoids from limestone of the Sosio Permian

blocks, Toumansky (1963) correctiy noted che

absence of rcliable représentatives of Waagcno-

ceras as well as Hyattoceras, Doryccrcu^ Clinolobus,

Epighphiocvras (ail known from Sictly). This Jist

can bc extendcd by the following genera:

Arisîoeeratoidess Altudoceras^ Hoffhrannia. and

Sizdires. Mosc of these genera arc olso not tbund

in the stratotype of Kubergandian stage.

GEODIVERSITAS • 1999 • 21 (3)

311

Kotlyar G. V., Baud A.. Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

We assume ihat the light grey limestone of

Kichkhi-Burnu Mountain is ot Kubergandian

âge [forms iroin the Kubergandian deposits of

Souiheastern Pamirs dcfined by Toumansky

(1935) and Bogoslovskaya (Chedija et ai 1986)

as Popanoceras aie assigned ro rhe genus

Tauroceras in chc prcsciit paperj. Grey limestone

on the right-bank of chc Alma River (Niknik

Creck) yiclding Propiiuicoceras, Agathiceras^

Cardîelhi. A^lrianites^ Stiicheaceras. and Para-

celtites^. is apparently of Kubergandian âge.

Small fommintfers

Analysis ol the Permian small foraminifers shows

that therc are five assemblages of different âges.

The oldcst .assemblage is found in two locaiitîcs:

in the Marra River Basin (l.oe. 110/1, 2, 4. 6, 7^

9, 20, 21), and on the eastern llank of the

Simferopül Réservoir (Luc. 125/1; Figs 4A, 5).

The most typical spedes ol the assemblage are

Neodheus aff. N. millîUndei A. M.-Maday and

Nodoinvohitaria jilinicu Han. The first occur.s in

the lowcr part of rhe Gnishik Formation (the

Neodisens milliloides zone) of Transcaucasia

(Pronina 1990), and in the Qixia Group

(Eolasiodiscus-Neodiscus mnoplngensis zone) of

Daxiakou, Xingshan County,. Hubei Province,

China (Zheng 1986). However, it has been iden-

tificd there as Neodiuits rnaopingeiîds Watig &c

Sun and Glowasptra duplicata Lipina. Nodo-

hivoliitaria pllnka Han fias been known pre-

viously from the Miaoling Formation of

northeascern China, that belongs to rhe

Neoschwagerina zone (Han 19S2). In addition to

Neodiscus aff. N. rnillUoides A. M.-Maday, the

following specics are in commun within the

Qixia Group - PaLieoiextitUiria piugguoemis Lin,

P. sp. (=■ P. loiigmptata Lipina) and Endothyra

saucra (Lin) (Zheng 1986). The presenee of

Neodisens aff. N milliloides A. M.-Maday in this

assemblage, ,i /,on.al species and index of the same

named zone of Transcaucasia, permirs us ro cor-

relate the assemblage of small foraminifers from

Loc. 110 (cxccpt Loc. 110/5) and Lot. 125/1 to

the Neodisens milliloides zone ol Transcaucasia,

and to the Eolasiodiseus-Neodiscus maopingensis

zone ol Hubei Province of China. The lasi zone

is correlared to the small foraminifer Pseudo-

vidalina delicata-Langella-Neodiscus maopingensis

zone and the fusulinid Neoschioageriva stmpkx-

Cancellrna neoschivagerinoides zone of the

Xiangboan Stage of China (Sheng & Jin 1994),

that correspond to ihe Kubergandian stage of the

Tetfiyan seule or ihc Roadian of chc scand-ard

scale.

The second assemblage of small foraminifers bas

been recogniscd in rhe limestone of Cape

L>zhicn-Safu, Simferopol Réservoir (Loc. 111/2,

3, 7;. Fig. 6B)- Atnong tbe numerous foraminifers

présent, rhe following .spccie.s arc diagnostic -

Tetratnxis scita L-in, 7*. linea Ozawa, Abadehcdla

htinanvnsis (Lin), Globivalvulina vonderschmitti

ReichcL C7. aff. G. permiana Tcberdynzev,

Postendothyrn novizkmna (Sosnina), and P. tissu-

rica (Sosnina). Ail species of tbis a.ssociaiion

occur in rhe Arpa Formation of Tr.mscaucasia

(Kotlyar/“Z *;/. 19S9J \n uAhadehella

hunanensis (Lin) and Tetrataxis seiut Lin are

known from the Douling Formation of the

Chinesc Province of Hubei and correlaled with

the upper part ot the Maokou Formation of

China (Lin 1985). Thus, the assemblage of small

toramiiiifers from Cape Pzhien-Safü is conside-

red to bc early Midian ot the Techyàn scalc or

laie Wordian of the standard seule.

’Fhc third assemblage ot small foraminifers was

found in rhe limestone block on the right sidc of

Izvcscnj^coty Creek in the /\lma River Basin at

Loc. 122d (Fig. 4C). This assemblage contains a

mixed launa whlch occurs in the Arpa Formation

[specics: Sphainotda [Psendosphairionid) rienii

G. Pronina, PseiidolangeHa geranossesisis

G. Pronina, P, dzhagadzurensis G. Pronina, and

P, füutfnfbrmh G. Pronina), .tnd in the KJiachik

Formation (species: Deekcrella sp. 1, Gtohi-

vahntlina cyprica Rctchel, G. vondenchmitti

ReicheL Orîhvvertella sphuerica G. Pronina,

Biiisedina pulchra Rchlinger, Septagathammina

sp., Rectoglandulina gerkei Sosnina, Pachypfdnia

eimula So.snina» and Parrisania sp. 1) of

4>anscauca.sia (Kotlyar et al. 1989; Pronina

1990). l’hc age of rhe association Irom

Loc. I22d is most likely lare Midian ol the

l'ethyan scale or Capitanian of the standard

scale. The early Midian species are probably

reworked.

312

GEODIVERSITAS ■ 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

The fourth assemblage üf small foraminifers was

found in ilie limescone block ai localiry 122b

(Fig. 4C). This association is represented by spe-

cies occurring in the uppermost Khachik and

Dzhulfa formations, and in the lower part of the

Akhura Formation of Transcaucasia (Korlyar et

al. 1989; Pronina 1990). Thereforcv rhe âge of

this assemblage is consldered to be Dzhtdfian.

The fifrh and ihe youngest association of small

foraminifers has been found in a limestone block

from Izvescnyakovy Creek in the Alma River

Basin (Loc. 113; Fig. 4B). This assemblage

contains a mixed fauna, thar occurs in rhe upper¬

most Kliachik and Dzhnlfa formations and the

lower part of the Akhura Formation {DeckerelLt

aff D elegarts Morozova, Nodosaria mirabilis

caucasien K. M.-Maday, J^gathammina ex gr.

A. rosella G. Pronina, and Mnltidiscm 1), and

in the Dorasham and the upper part of the

Akhura Formations [Postendoshyra gunngxiensis

(Lin), Nodosaria dorachamemis G Pronina,

Pachyphloia paraomta K. M.-Maday, P. ex gr.

P. pigmobesa Wang, Pscndolmigclla doraehamemis

G. Pronina, Colaaklla ex gr. C. minhna Wang,

and C. ex gr. C, Itpida Wang] of Iraoscaucasia

(Pronina 1990). Therefore, it is impossible to

establish the exact âge, but most likcly, this

assemblage is Dorashamian (Changsingian), and

the Dzhulfian species are reworked,

Fusidinids

Fusulinids from the Crimea Permian exotic

blocks bave been siudied by various workers

(Toumansky 1941; Hinor 6c Vdovenko 1959;

Miklukho-Maklay 1963), and they bave been

corrdated ro various stratigraphical levêls of

Early Permian to Laie Permian âge. Duvydov

(1991) investigated fusulinids from 13 exotic

blocks and numerous limcstonc pcbbles. Hc

rccognized ihc following biosiraiigtaphic levels:

(1) Misellina alicia^ M. dandine of upper

Bolorian âge (Loc. 123/3); (2) Caïudliua enta-

lensis of Kubergandian âge (Loc. 125);

(3) Praestimairina^ Neoschuuigerinn simplex

(Loc. 110/1, 3, 4, 9, Loc. lU/l) of Lower

Murgabian age; (4) Neoschwagerina craticulifera,

Afghanella, Sumatrina ot Murgabian age

(Loc. 110/5); (5) Neoschwagerina rnargaritae

Midian age (Loc. 110/la); (6) Yabeina opima of

Midian age (Loc. 123/2); (7) Pseudodiinbarula

minima^ Paradunbarula dallyi of Dzhulfian age

(Loc. 113). According to Datydov (1991), rhe

Crimea fusulinid succession ranging from

Bolorian (Kungurian) to Lace Permian

(Dzhulfian) are typicul Tethyan assemblages and

are very similar to rhe fusulinid faunas from

Elbiirz> Iran (Lys et al. 1978), The fusulinids

from several Crimean exotic blocks

(Loc. 110/20, 21, Loc. 122a-d) hâve been stu-

died recently by Nestell (Pronina Nestell

1997).

Six fusulinid assemblages appear to be présent in

the Crimean blod^j.

The First assemblage occuj'S in a small limestonc

block ac the raargin of rhe Marjino Village

within Simfèropol area (Loc. 123/3). The most

important forms are: Misellina cl-iindine (Deprat),

M. aliciae (Deprat), M. otakiensis (Fujimoto),

M. aff M. ermieri (Deprat). According to

Dav)dov (1991) and Leven (1980) chese species

are most characteristic for lace Bolorian.

’l'hc second onc is the most diverse and abun-

dant. It occurs in the largest limcstone block

exposcd in Marra River Basin (Loc. 110, except

Loc. 110/5), and in a small block on the eascern

side of rhe Simfèropol Réservoir (Loc. 125/1, 2,

Loc. 111/1). The most important and typical

species of this assemblage are: Neoschwagerina

simplex Ozawa, Cancellina (Shengella) ellipiica

Yang, Cancellina sp., Praesumotrtnn neoschwage-

rinoules (Deprat), Chmenella schwageriniformis

Shengv Ch. ebihstaensis (Lee), ParafitsttUna sp..

and F.opvlydiexodina sp. Tliis assemblage belongs

ro the Neoschioiigerina simplex-CancelUna neoscb-

wageu)ioides zone of ihe Xiangboan Stage ol

China (Sheng &: Jin 1994). 'Fhe age is most like-

[y lare Kubergandian.

The third assemblage occurs on the top of the

largest limcstone block from the Kichkhi-Burnu

Mountain (Loc. 110/5). With tlie exceptit)n uf

.some oldcr reworking species such as Armenina

sarabnriensis Toriyama &: Kanmera, Cancellina

sethapîiti Kanmera 6c Toriyama and others, this

GEODIVERSITAS • 1999 • 21 (3)

313

Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nesteil M. K., Belyaeva G. V. & Marcoux J.

assemblage contains the rypical Murgabian and

even early Miclian forms. Amoiig them are

Verbeeklna verbeeki (Geinirz), Neoschivagerina

craticulifira (Scliwager), N. colaniae O/awa,

N. ex gr. N. pingiiii Skinnei, Afganella icht-nki

Tbompst)ii, Suntairina sp. l'hcrcfore, che âge of

rhis assemblage is considered lo be Murgabian.

The founli assemblage occurs in a limestone

block at Cape Dzhien-Safu, Simferopol

Réservoir (Loc 1 11/2, 3a). The most cbarac-

teristic speties are Eopolydiexodimi sp., AJgbanella

cf. A. siiWiitrinaefarmis (Gubler), A. sp.,

Sumatrina rossica A. M.-Maday, 5. longissima

Deprai, S. bmds Levcn« and Knhlerimi sp. Thèse

specics are early Midian in âge in spire of che pré¬

sence of older taxa {Nvoschwagerind simplex^

Verbeekina. Armenina). Tliere is possibly some

reworking of older forms in tliis block. However.

there is clearly a dednite internai stratigraphie

succession présent in parts ol ihis block and imiil

closely spaccd sampics are studied, che précisé

âge of rhe block is not dear.

The fifth assemblage bas been recognised in the

limestone block on the righr bank of Izvestnya-

kovy Crcck in the Alma River Basin (Loc. I22d).

The assemblage cunsist.s of mixed early Midian

date Woidian) and late Midian (Capitanian) spe-

cies. MüSt likely, the âge is laie Midian or

Capitanian. A late Midian (Capitanian) assem¬

blage also bas been found in .sinall pcbbles ncar

Marjino Village (Loc. 123/2). Présent in these

pebblcs are Neoschtoagerinn irtiticiilifem

(Schwager), N, cf. N. kojensis Toumansky,

N. phigitis Skinner, Ytdmna opima Skinner, K cl.

K Yabe, and V nrbîculata ChcdVyà.

The sixth fusulinid assemblage is from the lime-

stone block ar localicies 122b and 113. Ir is pro-

bably Drhtdfian is âge and contains Codono-

fiisiella cf C. erki Rauser and Reichel'tna changh-

Sheng iR. Chang.

Brachiopods

Permian brachiopods are confined to the largest

limestone block in the Marra River Basin thar is

named Kichkhi-Burnu Mountain (Fig. 5). The

analysis of brachiopod associations from separate

parts of this block permits two assemblages to be

distinguished.

The oldest and most représentative assemblage is

characterisric of most of the Marta River block

(Loc. 110/1-3, 7, 9- 10. 21). These assemblages

are chatacieriscd by a prédominance of Bolorian-

Kubergandian spccics. Ragaria mtdcngraaffi

(Broili), Urmhtenia nuttina (Granc), Coninquia

modi'sra Grant, Tramenmtïa gmtiosa (Waagen),

Bdptina avantha (Waterbuuse & Piyasin),

Lwoproductiis kijseti Cirant, Amnnalona gUmrerosa

Grant. Phricodotbyris annika (Cibao) occiir in the

Rat Ruri Limestone of Th.iiland (Grant 1976).

Rtigaria nwkngraaffi (Broili) is described from

the Bitauni block of Timor (Broili 1915),

EvtcUtes gemcLiliUis Licharew, lichinaamcbm jns-

daUn (Kiitorga). Phrkodntbyris asiatka (Cbau),

Hfwiptycbina durvasicn Tsclicrnyschew are

known from Rolorian-Kubergandian deposits of

the Darvaz, Izchînoconchus fnsduim (Kutorga)

and Matgiinferit x'^irniolkti (Schellwicn) - from

the Trogkold I imestone ol vhe (garnie Alps and

Karawanken (hcbelKvien 1900). A number of

spccies bave also been described from Murgabian

and Midian deposits in .somc régions of the

Tetbys. Oghlnia dzlmgrensh Saryicheva is known

(rom che Gnishik Formation ol Trauscaucasia

(NeoschwdgeriH£î simplex and N. cmticulifera

zones), and EnteietC}, uihhievh Waagen is from the

Wargal Formation in Sali Range of Pakistan,

Martifjiti ceres (Gemmcllaro), Rostrnntcris infla-

îum (Cïcmmelhuo) îs from the Sosio Permian

blocks of Itvdy. However, these species are also

freqiienrly recorded in deposits older than

Murgabian and Midian, This iLS.scmblagc occurs

with rhe small foraminifcrs and fusulinids ol the

Neoschwiigmnü simplex- Cûnccllim neoschwt'Jgerk

noides zone, fhat is attributed to the CTihsian

Sériés (Sheng & Jin 1994) and with

Kubergandian (Roadinn) ammonoids. So, the

âge brachiopod .assemblage from the above-

mentioned localitics is most lîkely latc Kuber-

gandian.

rhe second assemblage occurs only at the top of

Kiebkhi-Burnu Mountain (Loc. 1 10/8). It is

extremely scarce and is represented only by a few

species — Ogbinia dzhagrensis Saryteheva,

Transennatia gratiosa (Waagen), Undynmellina cf

GEODIVERSITAS • 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

U. arnor (Geminellaro), and Per^nophricadothyris

pîilcherrima (Gemmellaro). AU of the species are

characterisric of Mijrgabian and lowcr Midiaa (or

Upper Wordian) deposics in the Techyan Realm,

although rhcy aiso occur in oldcr formauons.

Ilowever, it should be added that prcviously

other Midian and younger species hâve becn

reporied from rhe Marta River block. Species of

Dorashamian âge, such as GeyereUa tschernysche-

îvi Licharew, Plictttifetd* cf. ""PP hi'ijnrimassi

Licharcw, Richthofenia ccnicasica Licharew,

Leptodiis ricbihofini Kayser, Canumphorïa para-

nae Gemmellaro, and Jisuina nikitini

Gemmellaro, hâve becn rcportcd (Einor &

Vdovenko 1959; Licharcw 1966). lherefore.

within Kichkhi-Burnu Mountain there are pro-

bably blocks of varions âges, even of younger âge

than Midian.

Sphinctozoans

Permian sphinctozoans of the Crimea are repre-

senced by five généra - Colospongia Lalibc,

Crymncoelia Belyaeva, Vesicotubulafm Belyaeva,

Paradeningeriii Senowbary-Daryan 6c Schafer,

1979 and, SoUïtsia Steinmann, 1882. Repré¬

sentatives ot Colospojjgia are wide-spread in

Upper Carboniferous-Upper Triassic deposits of

the former USSR. Species of this genus occurring

in the Crimea are very similar in the shapc of

chambers, character of their fonction, size and

abundance ot vesicles to C, salinana (Waagen &

Wentzcl) known froni the Upper Permian nf

China and India, as well as from the Upper

Triassic of North America, and ihc European

Alps.

i'he species Crynunoelïa zavharovi BeKfacva, the

type species of the recemly established genus,

was described from ihc Permian of rhe Crimea,

and représentatives of the genus are as yet un-

known from oiher places. The nanire of rhe

porosity of the caienulace branches of this retro-

siphonate type allows the Crimean form ro be

assigned to the family Sebargasiidae. Wiihin this

family, thèse forms are niosi similar ro

Amblysiphonella Steinmann, 1882. That genus is

the most abundant among fossil sphinctozoans

from a systematic viewpoint and its âge ranges

from the Ordovician to the Upper Triassic.

However, Cryniocoelia, unlike closely similar

forms, is noted for a complex porosity of the

siphon Wall, that is very rare for sphinctozoans.

Vesicotîibnlaria prima Belyaeva was also First des¬

cribed from the Crimea and is similar to the pre-

vious genus. These forms are very pecuÜar

sphinctozoans, where an important part of the

skelctal structure is their vesicular fbubble) tis-

suc. Rcpresentaiives of the genus Vvsicocaulisy

parricularly V. alpirms Ott from the Upper

Triassic of the Alps is noted for an aporate cha¬

racter. Such taxa aie most closely relaied to the

described Crimean form in their shapc and skele-

cal structure. Représentatives ot rhe genus Vesi-

cocaulh are known only from Triassic deposits ot

rhe Alps, Pamirs and a fcw other régions.

Until reccntly, the gcnu.s Paradeningeria was

knowm only from the Upper ‘Lrias.sic of the

Pamirs, Alps, Himala}'as, and North America.

Permian représentatives Paradeningeria in the

Crimea belong to the recently established spe¬

cies, P. martae-nsh Belyaeva. Species of rhe genus

Sûllasiit are prévalent in the LTpper Permian of

Cambodia, Tunisia, Sicily, Venezuela. Texas, and

the Far East part of Asia. Isolâted occurrences are

known in the Triassic of the North Oaucasus and

the Far East.

Gencrally, the collection of sphinctozoans from

the Permian of the Crimea is rather small and,

thus, is probably poor in ternis of its systematic

composition. I hc taxa, Crymocoelia zacharovi

and Vesicotubularia prima, are noi diagnostic for

determining rhe âge of invosrigated blocks. As far

as rhe other taxa are concerned, Colospongia cf.

C salinaria, représentatives of the généra

Paradeningenn and Sollasia hâve a wide âge dis-

uibution from Late Permian to Late Triassic.

SUMMARY OF THE PeRMIAN

L StLidy of Crimean Permian exotic limestone

blocks denionstrates that carbonate sédimenta¬

tion from rhe late Bolorian to practicalfy the end

of the Permian occurred in the basin from which

rhese blocks were derived. A depositional envi¬

ronment on a shallow carbonate shelf is indica-

ted for these limestone blocks are predominandy

reefogenîc.

2. The analysis of ail faunal groups from the

GEODIVERSITAS • 1999 • 21 (3)

315

Kotiyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

Permian exotic blocks and pebbics shows rhat

rhey contain rich assemblages of primarily small

foraminifcrs and fijsulinids. Brachiopods, ammo-

noids, trilobires, and sphinctüz.üarvs are minor

constituenrs of ihese assemblages.

3- The distrilTiirion of fossils points not only to

differenr âges lor ilie various isolaied blocks, but

also in certain bloclo» to different âges of varions

parts of rhe samc block. Somctinics an internai

stratigraphie structure is évident in the larger

blocks, fer example, at the large block at Dzhien-

Safu. Mtxing of zonal species h often observed,

that interfères with précisé âge détermination,

even to stage level (Loc. 122).

4. The taxonomie composition of ail studied

groups definitcly points to rhe Tethyan composi¬

tion of the faiitias. vVImost ail zona] assemblages

of the Bolorian, Kubergandian, Murgabian,

Midian, as well as of rhe Dzhultian and

Dorashamian are présent. Pusulinid assuciaiions

display the greate^i ximilatity to the Hlburz

assemblages of northern Iran (Da\ydov 1991).

Small foraminifers arc comparable with those

found in similar âge sédiments in China, the Far

East and ’lranscaucasia. The brachiopods arc hkc

those from Sicily, Thailand and Iran, and amnto-

noids arc comparable with Sicily and Central

Asia assemblages.

5. A new Permian small block was discovered on

the righr bunk of the Bodrak River with a small

foraminifers fauna, l’he âge of the assemblage

from ühis block is most likely Dzhulfian or

Dorashamian (Chang-singian)

6. New data concerning the stage |o which the

Neoschwagennn simjAex-l^aestoHatrina neoschiua-

gerinaides zone belongs is most important.

Ammonoids huind together with a Insulinid

assemblage of this zone are clearly Kubergan¬

dian or Roadian, according to Zakharov. A

Kubergandian (Roadian) age is al-so confirmed by

the small foraminifers of the Ncoschwagerina sim¬

plex zone and, to a certain exrent, by brachiopods

whose assemblage is dominatctl by Bolorian and

Kubergandian species. This data of the conclu¬

sion fully confirms previoiis researctiers concer¬

ning assignment of chc Neoschwagerina

simpleX'Praestimart'ina neoschwagerinoides zone to

the Kubergandian (Sheng Ôc Jin 1994; Kotiyar &

Pronina 1995).

F(g. 7. — Locations of collection sites at the Triassic exotic

blocks along Izvestnyakovy Creek in the Alma River Basin;

A. locailty 117. B, locaüty 119. Matrix consists of the deposits of

the Mender subunit (Eskiorda Complex).

TRIASSIC EXOTIC BLOCKS

Alma Ri\'er basin

Triassic limestone blocks occur mainly in the

area of l/vcstny.ikovy Creek and in ihe Bt>drak

River area in the Alma River Basin (Fig. 4B). On

Izvestnyakovy Creek (Fig. 4R) thcrc arc lour

localitics (Locs 116-119) Irom which Pronina &

Vuks (1996) have dcscrîbcd the ferarninifera. In

rhe Bodrak River at Shvanov Ravine (Loc. 132),

a brachiopt>d assemblage has been determined by

Dagis (Dagis Shvanov 1965).

Lüc. 116

'fhis localily crops ont on ihc Iclt bank of

izvestnyakovy C'^reek about 750 m from ics

mouth. There arc blocks of grcy and lighr gray

micritic limcstone in size up to 4.5 m across. The

main block is a-calcilurite waekestone coiitaining

small Iragnicius of echinoids and criiïoido. Other

éléments are foraminifers and brachiopods.

316

GEODIVERSITAS • 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

ForaminiFers. Tolypanimimi irregularis (Salaj,

Borza & Samuel), Pilamminella gemeika (Salaj),

Gaudryina triadica Kristan-lbllmann, Malay-

spirinn ex gr. A/, alpina (Zaninetii &l Broen-

nimann), ''Çalcitornelld' gebzeensh Dagei,

Coronipora etrnscu (Pirini). Semiitwoliita bicari-

natn Blau» ,S. clari Kristan, Lamelliconus tunis

(Frenticen), Arenovidalina chialingchiangeyisis Ho,

Ophthalmidlurn luçidtmi (Irifonova), O, triadi-

cuni (Kjisian), Sig^milim bystrickyi Salaj, Borza

& Samuel, Nodosaria cf« N. dipartita Kristan-

Tollmann, N. sp. \ , Pseudonodosaria cf. P. vulga-

ta miilticamernta {Kriscan-Tollmann), Pachy-

phloides} sp., Austrocohmia camlknlata (Kristan-

'lollmann), Dmtalina zlambachcnsis Kristan,

Lenticulina rectafîghla Kristan Tollmann,

Dtwston?Ina sp.

Brachîopods. Etixiriella aimiolica (Bittner),

Laballn suessi (Winkler), L. slavini Dagys,

SiriHx'osîa emmrichi (Suess), Zugrnuyerclla koesse-

nensis (Zugmayer), Oxycolpella oxycolpos

(Emmrich), Nearetzia superbescens (Bittner),

Amphiclinn intermedia Bittner, A. tanrica

Moiseev, Rbaetina turneu (Bittner), Triadithyris

gregariafonnis (Zugmayer), Zeilleria bukowski

(Bittner), AuLtcothyropsh ahnensis (Moiseev).

Loc. } 17 (Fig. 7B)

This is a giant ÜmesLone block (100 m X 60 m),

occuring on rhe left bank of Izvesinyakovy Creek

about 1.5 km upstream from Loc. 116, and sho-

wing an inhomogeneous texture. Due to the non-

stratified aspect ol the block, ihe general micritîc

matrix pink colorcd in some part, and the présen¬

ce of numerous cavitics vvith geopetal calcitic

cernent, we consider char this block is part of a

mudmound. iTree sampled siie.s hâve been ana-

lysed from this block.

Loc. liyhample î

ForaminiFers. Tolypammina irregularis (Salaj,

Borza & Samuel), T. gregaria Wendt, Spiro-

plectarnmina spiTstlîs Salaj, Borza & Samuel.

Trochammina almfalensis Koehn-Zaninetei,

Duotitxis inflatus (Kristan-lollmann), Tèxîularia

ex gr. T. exigti/i (Schwager), Endotehn knepperi

(Oberhauser), Malnyspbina sp.,. MeandrosphrUn'^

sp., Semiinvoluia-bicanmiia Blau, S. -clari ICristan,

Arenovidalina chialingehiangensis Ho, Nodosaria

simplex (Terquem), ^Frondicularia woodwardr

Howehin, Austtocolomia .sp., Lcnticulina goettin-

gensis polygonata (Franke), Diphtremina astrofim-

brkita Kristan-Tollmann, Dimtomina sp.

Brachîopods. Euxinella anatolica (Bittner),

Cnmrhynchiu kiparisovae üagys, Laballa slaintii

Dagys, Zugrnayerella koesseriensis (Zügmaycr),

Shîucosfa emmrichi (Suess), Oxycolpella oxycolpos

(Emrnrich), Neoretzia superbescens (Bittner),

Amphiclina intermedia Bittner, A, tanrica

Moiseev, Rhaetina tanrica Moiseev, Triadithyris

gregariafimnis (Zugmayer). Besides these, Dagis

(1963, 1974) determined Rhaetina cf R. pyrifor-

mis (Suess), Æ tnrciça (Bittner), Zeilleria bukow-

ski (Bittner), Aulacùthyropsis abnensis (Moiseev).

Loc. ilJhample 2

A brachiopod assemblage analogous to locali-

ty 117/1 has been collecred from pink micrinc

limestone Only three species - Amphidma inter¬

media Bittner, Rhaetina taurwa (Bitrner), and

Zeilleria bukowski (Bittner) - are absent from

chose listed in Loc. 117/1.

Loc. 11 Jhample 3

ForaminiFers. Tolypammina irregularis (Salaj,

Borza àc Samuel), T. gregaria Wendt, Ammo-

baculites .sp., Dnotaxis inflatus (Kristan-

Fo 11 rn a n n ), Gau dry i n a t ri a d ictj Kristan-

Tollmann, ^7. racema Trifnnova, Phiniinvoluta

dejlexa Lei.schner, Semiinvolntn hicarinata Blau,

Angulodiscus parallelus (Kristan-Tollmann),

Arenovidalina chialhigcbiungensh Ho, A. depressa

(Lupcrco), Ophthabnldium carinatum Lcisclitier,

O. Jusiformis (Trifonova), O. cf. O. martanurn

Farinacci, G. tari Zaninetri & Broennimann,

Sigrnoilina schaeferae Zaninetti, Altiuer, Dager &

Ducrcc, Nodosaria cf. N. angulocameraia

Efimova> N. cf. N. clongaia (Salaj, Borza &

Samuel), N. aff. N. shablensis Trifonova,

Lenticulina sp., Astacolus sp., Turtispirillina sp.

Braebiopods. Euxinella anatolica (Bittner),

Robimonella nmstakunensis Moiseev, Laballa stavi-

ni Dagys, Zugrnayerella koessenensis (Zugmayer),

SinucQsta emmrichi (Suess), O.yycolpclla o.xycolpos

(Emmrich), Neoretzia stipcrbescens (Bittner),

Rhaetina pyrifonnis (Suess), R. gregana (Suess),

Zeilleria maisseieia Dag}^, Z austrica (Zugmayer).

Ammonoîds. MegaphyUites sp.

Crinoids and corals are also présent.

GEODIVERSITAS • 1999 • 21 (3)

317

Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

Loc. ns

This block (4.5 m X 2.0 m) is located 135 m

upstream from Loc. 117 on Izvesuiyakovy Creck

and is composed of light gray micritic limcstone.

It has yielded the following brachiopods —

Rbaetina taurica fvloiseev, Neoretzia stiperbescens

(Bittner), Zeilleria ausfrica (Zugmayer).

Loc. 119

Down thc creck from locality 117, four limesto-

ne blocks ranging from 1.5-5 m across were

found, as well as smaller angular limestone frag¬

ments (Fig, 7A),

Loc. 119/sample L 929-1

This is thc lat^sr block, about 5 m across, and

consists of a coarse biocalcarenite grainstone with

radiaxal cernent and mud late infilling. The ske-

letal cléments are crinoids, brachiopods, cchi-

noids, gastropod.s, sponges, loramiaifers and

intraclast.s. The environment is ol a shallow,

high-energy carbonate platform.

Foraminifers. Tnlypummina gregaria Wendt,

Trochammhm ahntalensis Koehn-Zaninceti, T. jau-

nensis Broennimann Page, Duotaxis inflatus

(Kristan-Tollmann), D. meiula Kristan,

Gaudryina maâtea Kristan- Ibllmann, G. trumica

Trifonova, PabeoHtuoifellû inendionalis (L.uperto),

Textuiariu ex gr. T. exigitti (Schwager), f.udotrha

nustrotriadlcu (Oberhauser), £. kuepperi

(Oberhauser),, Malayspirina bicameratn (Salaj),

M. wirtzi (Koelm-Zaninetii), ''CakLUmielld' geb~

zeensis Dager, ïHaniinvolula cannatu Leischner,

Coronipota eirusca (Pirini), Seniihwoluta bicarimta

Blau, S. dari Kristan, S. vtolae Blau, Lamellicanus

tiirris (Frentzen), L. inuhispirus (Oberhauser),

TrochojielLi ^anosa (ï'Tcntùùn)^ Arcmindalina chia-

lingchiangcmis Ho, Ophthal-midium exiguum

Koehn-Zaninetti, O. fitsifortHis (Trifonova), O. Id-

schneri (Kristan-Tollmann), O, lucidum

(Trifonova), O, trtadicinn (Kjistan), Sigmoilirm

bystrickyi Salaj, Borza & SamueL 5. plectosptm

(Oravecz-SchefFer)) Gnlcantlla pantkae Zaninetti

& Broen ni man n, MilUdipora cuvillieri

Broennimann & Zaninetti, OphtnhniponP sp.,

Nodosaria sp. 1. ScputiriguHna cl. S. iHmsepta Hc

&r Norling, Aastymolomin ex gr. A, cnnaliculata

(Kristan-Tollmann), Lenticulina rectangiila

Kristan-Tollmann, Astacolus sp., Duostomina sp.

Brachiopods. Oxycolpella oxycolpos (Emmrich),

Hhaetwa pyriformis (Suess).

Loc. 119lsamplc2, 929-2

This sample is a llne-grained, mud supported

biocalcilurite with crinoids, foraminifers, thin-

shelled ostracods and bryozoan fragments. The

numert)tis cavitics with light mud infilling are

typicol of a mudmound on a shallow slope.

Foraminifers. Gaudryina tiiassica Trifonova,

Coronipora etrusca (Pirini), Scmuuvolutu hicari-

fjata Blau, Anguladiscus ex gr. A. expansus

(Krisran-Tollivann), Paraophthalmidium sp.,

Ophthahnidium jiisiformis (Trifonova), O. cf.

O. martanum Farinacci, O. sp. 1, Quinquelocu-

lind^. nnddformis Kristan-Tollmann, Sigmoilina

bystrickyi Salaj, Borza Sc Samuel, S. plectospira

(Oravecz-Schctfcr), 5. ichaeferae Zaninetti,

Altiner, Dagcr 6c Ducret,. Nodosaria cf. N. clon-

gata (Salaj, Borza & Samuel), N, uhida elovgata

Franke, '‘'Frondiru/aria uoodîoardr Howehin,

Atistrocolûuna canallculata (Kristan-Tollmann),

A. wz/;ï(7vf///Oberhau.scr, Lenticulina sp.

Brachiopods. HuxincUa anaiolica (Bittner),

Sepudiphoria fissicostaui (Suess), Cturirhynchia

klptîrisuvae Dagys, Lahalla sut'ssi (Winklcr),

Oxyco/pdia oxycolpos tEmmrichj, Ü. robinsoni

Dagys, Amphidina laurica Moiseev, Triadithyris

gregariafarmis (Zugmayer).

Loc. I19tsamplv 3

This block consists (»f graded, resedimented

pinkish fine waekestone — coarse skcletal pack-

stone with echinoids, crinoids, brachiopods and

foraminifers. l'iii.s is a considered to bc a distal

slope deposit.

Foraminifers. Tolypammina gregaria Wendt,

Coronipora etrusca (Pirini), Semiinvoluta hicari-

nata Blau, Lamdliconm îurris (Frentzen),

Ophthahnidium leischrieri (Kristan-Tollmann),

O. lucîdmn (Trifonova), Sigmoilina bystrickyi

Salaj, Borza 6i SanmeJ, S. schneferae Zaninetti,

Altiner, Dager 6c Ducret, Miliolipora cuvillieri

Broennimann & Zaninetti, Nodosaria sp. 1,

Reciogliindnlinnt sp., Lenticulina sp., Duostomina

sp., Turrispinllina^, licia llcia Blau.

Loc. 12la

Numerous exode blocks of gray limestone occur

318

GEODIVERSITAS • 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

near Drovyanka Village. The species Monotis

caucasica (Wittenburg) and M. haiieri Kittl were

found (détermination of A. Moiseev and

I. Polubotko).

Loc\ 132

A brachiopod assemblage of Shvanov Ravine

contains Costirhynchia mentzeli (Buch),

Hirsutella hirsuta (Albcrti), Mentzelin sp.,

Koevcskallina koeveskalliensts (Boeckh).

Punctospirella cf. P. frügilis (Schlotheim),

Costispiriferinu cf. C. manca (Bittner),

Angîistothyris nngustaeformis (Boeckh). This

assemblage is of Anisian âge. However, \vc can-

not confirm that this assemblage is coming from

an exotic block, and not from the matrix.

SiMFEROPOL AREA

Loc. 130

rhe second important location of Triassic exotic

blocks is in the Salgir River Basin in the

Simferopol area (Pig. 4A). Sonic blocks, sépara-

ted from each other, were observed near

Petropavlovka Village (Loc. 130) in ihe sandsto-

ne and conglomeraie of ihe Lskiorda Sériés.

The block of Loc. 130 is a crinoid and algal

lime-packsione yielding abiindunt bnicbiopods,

single amnionoids, bivalves, and gastropods. The

brachiopod a.ssemblage contains - Eiixinella ana-

tolica (Bituier), Laballü seessi (Winklcr)> i. davi'

ni Dagys, Sinucosta cmmrichi (Siiess),

ZugniayereHa koasensn (Zugmayer), Oxycolpella-

oxycolpos (Pmmrich), AviphtcUna taurica

Moiseev, Rhnetina uiurka Moiseev, Lohothyris

sp., Zeilteria hukowski (Bittner), Aidacothyropsis

elmensis (MoiscevT This data is compiled from

earlicr workers {Moiseev 1932; Dagis 1963,

1974; Shalimov 6c Slavin 1973),

The following ammonoids occiir with these bra-

chiopods: Pamcladhcites diuUirnum Mojsisovich,

Arceitei ex gr. A. intuslahiatns Mojsisovich, and

Platites sp. Shevyrev (1990) corrclated ro the

Lipper Rhaetian or the Choristocents rnarshi zone

of rhe standard scale.

An/Mysis of faunal assemblages

Ammonoids

.Ammonoids are rare in the pink limcstone ont-

cropping on the upper part of Izvestnyakovy

Creek (Loc. 1 17/3). Only one shell, Mega-

phyllUes sp., was preserved well enough to bc-

deterraincd by us. Représentatives of this genus

are rccorded from rhe upper part of the Lower

Triassic into the Upper Triassic. Wirliin the

Alpine Région, they are known only from the

upper Anisian to Rhaetian.

Forammifers

Pronina & Vuks (1996) gave the first detailed

information about Triassic foraminifers of the

Crimea. Ail of the foraminifers that were .studied

occur in exotic blocks (l.ocs 1 16, 117, 119:

Figs 4B, 7). The assemblages are of sim'ilar gene-

ric and spécifie composition, which allows them

to be considered ihe same âge. They arc charac-

terized by the presence of miliolids and involuti-

nids, the most significance foraminifers for

dating Lower Mesoz-oic deposits.

In this assemblage,, rhe following species arc-

known m Norian-Rhaetian deposits: Semiinvolîtta

clarï Krisran, Angulodiscns pamllelus (Kristan-

Tollmann), A. ex gr. A, expansus (Kristan-

Tollmann), Sigmodina hystrichyi Salaj, Borza 6i

Samuel, S. schaejhne Zaninetti, Altincr, Dagcr &

Ducret, Galeanella panticae Zaninetti &

Broennimatin, MUtolipora aivillieri Broennimann

Zaninetti. In addition, species are présent thaï

occur in deposits not oldcr than the Rhaetian, and

sometimes even in younger deposits: Semunvaluta

bicarinata Blau, Trovhoneila granosa Frentzen.

Ophthalmidium leischneri (Kristan-Tollmann),

SeptalinguHna tetrasepta He Norling, and

TunupinlliniP Hcia livin Blau.

Considered togeihcr, ihc foramlniferal assem¬

blages of the Crimea arc similar: to the lare

Norian (Scvarian)-Rhaetian ofthe Khodz Group

of the Northwest Caucasus (Efimovâ 1975;

Anonymous 1991); to the late Norian (Lacian-

Sevatian) Mîliolipom cUvillieri standard zone of

the Carpathian-Balkan and Hellenic Realm

(Salaj et ai 1983, 1988); to ihc upper Norian

Kocagedik unit of Turkey (Ahiner 6c Zaninetti

1981): and tu the Norian-Rhaetian Asinepe

Limcstone of Serani, Indonesia (Al-Shaibani et

ai 1983).

Accordingly, we conclude that the age of the

foraminiferal assemblages of the Crimea can be

either late Norian or Rhaetian. Most likely, the

GEODIVERSITAS • 1999 • 21 (3)

319

Kotlyar G. V., Baud A., Pronina G. P., Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

âge is Rhaetian, bccause species are in the asso¬

ciations whose distribution is Ümited to the

Rhaetian. However une Rhaetian index spccies,

Triasina hantkeni Majzon, was nor found in the

Crimea blocks.

Brachiopods

Moiseev (1926, 1932) siudied the first Triassic

brachiopods from exotic blocks of the Crimea.

Later, the numerous brachiopods collected by

Moiseev, Shalimov, and Slavin wcrc determincd

and partiy described by Dagis (1963, 1974). The

brachiopod assemblages were considered to be

the of mixed Norian-Rhaetian agc.

Dagis identified the Middle Triassic brachiopod

assemblage in Shvanov Ravine in the Bodrak

River Basin (Loc, 132). It contains Costirhym'hia

mcfitzeli (Buch), Hirsutella hlrsuta (Alberti),

Mentzclia sp , Koeveskallhia koeveskalUensis

(Boeckh), Pufjçtospirella cf. P. fnigUis

(Schlotheim), Costispiriferiva cf. C. rnauca

(Bittner), and Angustothyris afigustaeforrnîs

(Boeckh). These brachiopods arc of Anisian agc

(Dagis &: Shviinov 1965). However, wc cannot

confirm that thLs assemblage is characteristic of

the exolic blocks, and iioi rhe tnairix.

New investigation of dic brachiopod assemblages

from chc numerous Ümestone blocks and pcbbles

of the Crimea confirms che spécifie composition,

and more precisely, defines their stage and zonal

position. Analysis of ail Triassic brachiopod asso¬

ciations from invesrigated exotic blocks sho^vs that

there is only onc distinctive brachiopod assembla¬

ge of Rhaetian âge. h occurs in che large

(Loc. 117) and smailcr (Locs 116, 118, 119)

limestonc blocks and pebble.s exposed in ihe Alma

River Basin, and in the valley of Izvestnyakovy

Creek (Fig. 4B. The sanie brachiopod assem¬

blage has heen found in the Salgir River Basin

near Perropavlovka Village (Loc. 1.30).

Rhaetian species Irom dilfereni régions of the

West Tethys domiiiate thîs assemblage. They are

— Ro hî Nso licllct in as takau eyn is Moiseev,

Septalîphoria fissicastaia (Sue.ss), Lahalln nmsi

(Winkler)v Zugrnayerdla koessenemts (Zugmayer),

Sinucostit emmrichi (Stiess), Oxycolpella oxycolpos

(Emmrich), Neoretzia superbescens (Bittner),

Rhacîhia gregaria (Suess), R. pyrifonnis (Suess),

Triitdiihyris gregariaformh (Zugmayer), ZeiUma

austrica (Zugmayer), and Z. bukoivski (Bittner).

The Crimea brachiopod assemblage is most simi-

lar to rhe Rhaetian brachiopods from the

Koe.ssen hed.s of Alps (Dagis 1974). The lollow-

ing species are comniou - Septaliphçria fhsicosta-

ta (Suess), Laballa suessi {Winldcr), Zugmayerella

kuesieriemis (Zugmayer), Sinucosta rmmrichi

(Sues.s), Oxycolpella oxycolpos (F.mmrich),

Rhiictina gregaria fSuesx), and Triadithyris gn-ga-

riaformis fZugmaycr). The Crimea brachiopod

assemblage is also similar to Rhaetian brachio¬

pods of l.lrnava Slovenia. The commun forms

arc SepiuUforia fissicostata (SueSs), Laball-a suessi

(Winklct). Zugnuiyêrtlla koessenerish fZugmayer),

’^iimuosUi cmyntichî {Sue.ss)^ Neoretzia superbescens

(Bittner), Rhactinapyriformis (Suess), Triaditlyris

gregioiaformis (Zugmayêr), and Zcilleria austi'ica

(Zugmayer) (Dagis 1974). Likewise, the a.ssem-

blapc is comparable to Majkopella rnarizavini

beds of Turkey. The commun forms are

Euxiuella anatolica (Bittner), Labalia suessi

(Winklcr), Sinucosta ennnrichi (Suess.), Rbaetina

turcica (Bittner), ZciUeria austrica (Zugmayer),

and Z. hiikowski (Bittner) (Bittner 1892). Finally,

Uiey are similar to the brachiopods collected

from exotic blocks of Balkanian. The common

forms are Zugtnayerella koessenensis (Zugmayer),

Sinucosta ematrichs (Suess), OxycolpelLi oxycolpos

(Emmrich), Amphiclina iniermedta Bittner,

Rbaetina gregaria (Suess), and R. nm'ica (Bitlner)

(Dagis 1963h

rhe red Hmestone of the upper part of the

Khodz Group of die Northwest Caucasus, that

lies ahove beds with Monotis caucasicay is the

same âge as the Crimea exotic blocks. They both

contain species in common - Euxinella anawlica

(Bittner), Crurirhynchia kiparisovae Dagys,

Zugmayerella koessenensis (Zugmayer), Sinucosta

emmrichi (Suess), Oxycolpella oxycolpos

(Emmrich). Neoretzia superbescens (Bittner),

Amphiclina intermvdïa Bittner, A. ranrica

Moiseev, Rbaetina turcica (Bittner), R. pyriformis

(Suess), Zeilltria bukoivski (Bittner), and Z. mois-

selevi Dag\*N.

Ail ihc above-mentioned brachiopod assem¬

blages,. considered carlicr as Norian-Rhaetian, are

actually the youngest Rhaetian associations. We

320

GEODIVERSITAS • 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

agréé with Shevryev (1990, 1995) that they can

bc attributed to rhe Vandüites sturzenbaurni zone.

Co-occurrence of these brachiopod assemblages

and such ammonoid spccics as Paracladiscites

diuturntis Mojsisovidi, Arcestes ex gr. A. intudii-

hiaius Mûjsisovich, and Platites sp., that werc

establishcd as bcds wirh Platites-RhacophyUim

neur Petropavlûvka Village (Shevyrev 1995),

allow us to specily thc stage and zona! position of

this association. An analogoiis, but more diverse,

ammonoid association occurs rogeiher wirh

Rhaetian brachiopods in other régions of the

Techys, inclüding thc Northwest Caucasus in rhe

upper part of thc Khodz Group. It is represented

by the présence of Paraclad'iscites diiiturnus

Mojsisovich, Megaphyllites i)7sectm iMojsisovich),

Stenarcesm leiost^'acus Mojsisovich, Arcesies ex gr.

A - intuslahiatus Rhacopbyllifes dehilis

(Haucr), Platites polydactilm {Mojsisovich)

(Shevyrev 1995). Evcr\whcrc in the West Tethys,

Rhaetian brachiopod assemblages usually occur

in pink or red limestone.

The Norian-Rhaetian, but not Rhaetian age, ot

the above-menrioned mixed brachiopod associa¬

tion has been derermined by the présence in

these beds of Norian ammonoids. However,

Shevyrev ( 1990) believes that thc appcarancc and

great development ol^ heteromorph ceratites is an

important event in thc Lare Triassic ammonoid

succession. It allows one To consider the Rhaetian

as important in the development of Triassic

ammonoids. Nevertheless, we are following

Dagis (Dagis & Dagis 1990) in drawing the

Rhaetian lower boundary at the base of the

Cachloceras suessi zone.

StIMMARY OF TME TRlASbJC

1. Triassic exotic blocks contain rich as.semblages

of foraminifers, brachiopods, rarer ammonoids,

bivalves, and sphictozoans. Reworked forms are

practically absent.

2. rhe taxonomie composition of the brachio¬

pods and ammonoids shows the greatest similari-

ty to Rhaetian assemblages of ihe West Tethys,

the Northwest Caucasus, thc Alps, the

Carpathians, and Turkey. The foraminifers are

most similar lo ihose in the Northwest Caucasus,

the Carpathian-Balkan and Hellenic Realm,

Turkey, and Indonesia.

GEODIVERSITAS • 1999 • 21 (3)

3, Some limestone blocks (Loc. 121a) containing

abundant MoTWtis belong to the Sagenites quin-

quepunctatiis zone of thc Scvatian (Dagis &

Dagis 1990), or to the upper part of the Norian.

4, l'hc analysis ol faunal éléments from Triassic

exotic blocks (Locs 116-119, 130) allows us to

consider that they arc ol Rhaetian age and accor-

ding to Dagis & Dagis (1990) belong to the

Vandaites sntrzenbaumi zone.

5, The Anisiaii faiina Irom the Bodrak River

Basin probably does not corne from an exotic

block.

Acknowledgements

This research was made possible by a grant from

the Peri-Terhys Program (Grant No. 95-17). Wc

arc grateful to thc Gcological Insritutc of the

Acaderny ot Sciences of the Ukraine for their

help in arranging invitations and support. Dr A.

Dvoret.sk}' in Simfcropol provided valuable logis-

cical support for visiting localities. Our thanks

are due to I. Chedija and G. Kropatcheva for

their help in the field collecting. We would also

like ro rhanks Yu. S. Biske (SPB University) and

N N. Makarov for licld 3.ssi.stance and consulta¬

tions. Dr E. Yochelson critically rcad the manus-

cript and Prof. F. Cordey (Lyon) gave help for

the chapter “Crimea-Pontides”.

REFERENCES

Aldncr D. Ô: Zaninettl !.. 1981. — t.e Trias dans la

région de Pinarbasi, Taurus oriental, Turquie: uni¬

tés lithologiqucs. niicropaléontologie, milieux de

dépôt. Rhnstii îtnliana di Paleoïitolvgia 86 (4):

705-760.

Al-Shaibani K., Carter D. J.. Zaninetti L. 1983. —

Gcological and micropaleontological investigations

in the Upper Triassic (Asinepe Limestone) of

Seram, Outer Banda Arc, Indonesia. Archive des

5a>«m36 (2): 297-313.

Anonyraous 1969. — Geologiytt USSR. Krimea. f. 8.

Nedra, Moscow. 339 p. fin Russianj.

Anoiwmous ]99]. — Pr.ictical manual on niicrofau-

na of rhe USSR, Jn Mesozoic Foramwifrru, volume

5. Leningrad, 373 p. [in Russian],

Aydin M. et iiL 1986. — Tlie geolog}' of the area bei-

ween BiiUidag and Cangaldag (Kasi«irnonu). Bulletin

oftbe Gevlogical Society of Turkty 29 (2): 1 -16.

Banks C. J. 1997. — Me.sozoic Stiike-Slip Back-Arc

Basins of thc Western Black Sea Région, in

Robinson A. G. (ed.), Régional and Petroleum

321

Kotlyar G. V., Baud A., Pronina G. P.. Zakharov Y. D., Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

Geolog)' of tlic Bl;uk-Sca and Surrounding Région,

Memoir of ihe Atnerictin Anociaiion of Petroleum

Geologuts fïS: 53-62.

Bittner A. 1892. — Brachiopoden der Alpinen.

Abhandlhungen der Kaherlich-Koniglich Geolo-

gnchen Jieichsansuüt, 14, 335 p.

BogoslovskaYa M. F. J984. — Ammonoids: 248-257

[in Ruwian), in Kotirar G. V. & Siepanov D. L.

(cdvs). Main features of StriUtgrafdiy of Permian

System in îhe USSR, Nauka, Leningrad.

Broili F. 1915. — Paniische Brachiopoden der Insel

Letti. in Mnlengraafti G. A. F. (ed.), De Geoiog)'

van hcc FJIand I crti, Ducch East Indies, Dienst,

Mijn JtiarburgMijnwezen 79/*?, 43 (5): 187-210.

Chedija I. O.. Bogoslüvskaya M. F., L'iavydov V. I. et

al. 1986. — Fusuiinids and .Ammonoids in rhc

Kubergandian stracotype (Southeascern Pamir.s).

Ezhegodnik VPO 29: 28-53 [in Russian].

Dagis A. S. 1963. — Lîpper Triassic brachiopods ol

the South of the USSR. Nedra, Alostow, 248 p. [in

Russian].

— 1974. — Triâssic brachiopods. Iransactions of

Institut of Geoh^ and Geophysic, Novosibir.sk, 214,

323 p. Iin Russian).

Dagis A. S & Dagis A. A. 1990. — In favour of the

Rhaeiian. Geology and Geophysic 5: 35-44 [in

Russian).

Dagis A. S. iSi 8hvanov V. N. 1%5. — About disco-

very of the Middle 'l‘riassic within the Faurida

Formation of rhc Crimea. Doklady Academy of

Science USSR, Earth Sciences 164 (I): 23, 24.

Davydov V. L 1991. — Permian deposits of the

Cri me j: A37-38, in Chuvasho\’ B. l- & N ai ni

A. E. M. (cds), Perrnian System of the World.

Program and Abstract, ESRI, Columbia SC, USA.

Eflmova N. A. I9‘^5. — Foraminifera from dcposiis

of Khodz Group of the Northwestern Caucasus

(Tkhach River), Tmdy VNIGNI 171: 47-61 [in

Russian].

Einor O- L. & Vdovenko M. V. 1959. — New data

on the Upper Paleozoic fauna of the Crimea.

Natikovi ztipiski KS (6): 49-67 (in Ukrainian).

Fokht K. K. 1901. — O drevniidi osadochnykh obra-

zovaniyakh Kryma, Trudy St-Petersbitrgskogo

Ohshcheslm EsiestvoispytateUy 32 (1): 39-44 [in

Russian).

Gorür N. 1988. — Timing of opcfiing of the Black

Sea Basin. Tectonophysks l47: 247-262.

Grant R. F.. 1976. — Permian Brachiopods from

Southern T\\m\,\uA. Journal rf Paienntolog)' 50 (3),

269 p.

Han T. 1982. — The Laie Eatly Permian Foranii-

nifera in the North part of Northern China.

Bulletin Slwnyang Institut ofGeido^» 3 (4): 99-112.

Koronovsky N. \7 S: Milcev V. S. 1974. — O .soot-

noshenii odozheiiyi tavricheskoi .serii î eskiordin.s-

koi svity V doîine i. Bodrok (Gorny KA m). Vestntk

Moskovskogo Universiteta A (1): 80-87 [in Russian).

Kotlyar G. V. & Pronina G. P. 1995. — Murgabian

and Midian Stages of the Tethyan Reaim.

Pcnnophilesll: 23-26.

Kotlyar G’. V., Zakliarov Yu. D., Kropatchcv'a G. S.,

Pronina Ci. P., Chedija l. O. & Burago V. I.

J 989. — Evolution of the Latest Permian Biota.

Midian régional stage in tbc USSR, Nauka,

Leningrad. 185 p. (in Russian).

Leven £. Ya. 1980. — E^p/anatory note to the strati¬

graphie seule of Permian deposiu ofthe Tethyan area.

VSEGFd. I-cningiad, 51 p. [m Ru.ssian|.

— 1996. — Midian Stage of the Permian and its

boundaries. 'stratigraphy and Geolagiealcarrefation 4

{6):20-.ll.

Licliareav B. K. (ed.). 1966. — Stratigrapby ofthe

USSR Permian System. Nedra, Moscow. 536 p. [in

Russian).

Lin T. 1985. — Lace Early Permian Foraminifera and

its poJeoecology in Jiahe, Hunan, Bulletin Yichang

Iiistitute of Ge(dog^' and Alineral Resources CL4GS 9:

43-52.

Logvinenko N. V.. Karpova f. V. & Shaposhnikov

D. P, 1961. — Lirhology and gencsis ofthe

Taurida Formation of rhe Crimea. Kharkov

Uriiversity, Kharkov, 400 p. |in Russian).

Lys M., Stampfli G. & Jenny J. 1978. —Biostrati¬

graphie du Carbonifère et du Pertnien de FF.lbourz

oriental (Iran du NE). Notes du Laboratoire de

pedéontolo^dc de rUnnrrsjtè de Genet^el : 63-99.

Marcoux J, & Baud A. 1996.— Late Permiau o» Late

Tria.vsic Palaeocnvironrtienrs. Three snapshm.s: late

Murgabian, late Anisian, late Norian: 153490 in

Nairn X.. Ricou L. fi., Vrîdinck B. fie T4tTcourt J.

(cds). rhc Tethys océan. Plénum Pre.ss, New York

and L.ondon.

Marcoux J.. Baud A., Ricou L. F., Gactani M.,

Kry.srvn L., RcJlion Y.. Guiraud R., Bcs.se Gallet

Y., Jaillard E., Moreau C. fie Theveniaut H.

1993. ■— Late Norian (212-214 Ma): 35-53, in

L^ercourt )., Ricou L. E. fie Vrielynck B. (eds),4r/(Ær

Tethys, Paldeoenoironmenuil mups. explanaiory notes.

Gauthier-Villars, Paris.

Vliklukho-Maklay A, D. 1963.— Upper Paleozoic of

the Middle Asia. LGü, Leningrad, 328 p. [in

Russian).

Milecv V. S., Vishnevsky L. E. Frolov L"). K.

1989. — Tfiassic and Jurawiic Systetn: 5-66 [in

Russian], in Mazarmich O. A. &r Milecv V. S.

(eds), Gèologica! stYueture of the Kiieba Uplift ofthe

Gorny Crimea. Nedrâ, .Mosco^v.

Moiseev A. S. 1926. — About Tria.ssic limestones

near Beshui Village in the CYimeà. [zi^esth* GeoLgis-

cheskogù Gomiteta 45 (7): ~47-'^54 im Rtusslan).

—- 1032. —About the Fauiu and llora oi Vriassic

deposits of the Salgir River Basin in the Crimea.

Jzvestia Vsc^oyusnogo Geologo-Razvedoehinogo

olTedineuiya 51 (39): 5yi-i>06 [in Russian).

— 1937. — From Simleropol to Yalta: 23-3**. in

Moiseev A. S (ed.), The Southern exeursion, the

Crirnean autononwus Soviet Socialist Republic . I7th

322

GEODIVERSITAS • 1999 • 21 (3)

Permian and Triassic exotic blocks of the Crimea

International geologicdl Congre^i. Moscow. Chief

Editorial Office, Leningrad.

— 1939. — New data about che Upper Triassic of

the Nortii Oaucisus and Criniean ASSR. Doklady

AN USSR. M 0 .SC 0 W 23 (8): 816-817 [in Russian].'

Muratov M- V. 1949. —Tecionic and Geological

Histof)' of the AIpyniaii geûS)Ticlinal région or the

South European part of the USSR and ajaceni

coiinrries, in ïekwnika USSR. Volume 2. Moscow-

Leningrad, SK) p. iin Rus-'vian).

Muralov M. V., Arkhipov I. V. & L^penskaya Ye. A.

1984. — Srructura) évolution of the Crimean

Mountains and compaii.son with the western Cau*

casus and the eastern Balkan Range. Jnkrnational

Geologica! Revieiif 26: 1259-1266,

Onder F. 1990. — Rcmanpics. taxonomiques .sur les

conodontes de la foiniafinn triasique de Kayab.asi.

Cumhuriyer ÜnhcrsUt'ü Afübendidtk l'akultesi

Dergisi, SeneA Yermlimleri, Sivas, C 5 (1 ): 67-69.

Pronin.i G. P. 1990. — îhe Sniall Foraminifera oj the

Üpper Fermtan of Tnwscaucaiuî and thnr strattgra-

phic sigriifit'ani.f. Thesis of di.ssenation, extended abs-

traa, VSEGEL Leningrad, 22 p. [in Rnssi.an].

rVonina G. P. N. Vuk.s V. Ja. 1996. — New daca on

the Triassic Furaniinif'ers of Crimea, in Braga G..

Finotti F. & Piccoii Ci, (eds), Report ofthe Shallotv

Tethysd. Supplemtnco agli Annali dci Musei Civici

di Rovereco. Scrione: Arrheologia, Storia c Sckn/e

naturalc, 11; 215-228.

Pronina G. 1'. &C Nesicll M. K. 1997- — Middle and

Late Pcrnii.in Foraminifera from cxotic limescone

blocks of the Alma River Basin, CYimea, in Ross

C. A., Ross J. R. P. ÔC Brcnckle P. L. (eds), late

Paieozok Fonitni-nitera: tlteh' hmteatig^'ciphy, eoolu-

rion, and paltonohgy, and the MidAJarhomfernus

honndary. C’iuhmân Foundarion foi Foraininiferal

Research. Spec. Publ. 36: 111-114.

Robinson A. G. & Kerusov H, 199^. — Siratigraphic

and strutiural dcvclopincnr of the Ciulf of Odessa,

Llkrainian Black Sea: implications for petroleuin

exploration, tn Robinson A. G. (ed.), Rcgional and

Petroleum Geolugy of chc Blat:k-.Sca and

Surroundiag Région. Menioir ofthe American

Association of Petroleum CieologiiTs 68: 183 226.

Sala] J., Borza K. & Samuel O. 1983. — Triassic

Forarninifers of the West Carpathtans. Bratuslava,

213 p.

Salaj J., Trifonova F.., Gheorghian D. C7oroncou V.

1988. — The Triassic Foraminifera miciobiostrari-

graphy of the Carpatlrian-Baikaii and I lellenic

realm. Miueutlin Slov/tquia 20 (5) 3fi'^-41 5.

SchcMwien F. 1900. — Die F.uina dtr Trogko-

felschichren in den Karnischen Alpen und den

Karawanken. F. 1. Die Brachiopoden. Ah-handlun-

gen des Geobgisches Reichsansialt 16(1), 122 p.

Sengôr A. M. C. 1984. — The Cimmetide C9rogenic

System and the tectonics of Eura.sia. Geologicat

Society of America, Spécial Paper 195: 1-82.

Shalimov A. I. 1960. — New data on the Upper

Triassic, Low'er and MiddJc Jurassic straiigraphy of

the Southwest part of the Gorny Crimea. Doklady

Academy of Science USSR^ Earrh Sciences, 132

fl-6): 558-561 [in Rus.si;in|,

— 1963. — Voprosy srratigrafîi i proiskho/hdeniya

flishevoi Tavricheskoi Strii (Gorny Krym). Frudy

Leningradshogo Ohshehestva F.stestvoispytateley 73

(Ij; 54-64 [in Rus.sian].

Shalimov A. I. Slavin V. I. 1973. — The Crimea-

(.’aucasian Gcosyncline; 343-357 [in Russian], in

Stratigraphy of the USSR Triassic System. Ncdra,

Moscow.

Sheng J. &C |in Y. 1994. — Corrélation of Permian

deposits iii Ciiina, Pataeoworld4: 14-113.

Shevyrev A. A, 1990 — Ammonotds and chronoslratT

g>'apby of üte Triassic. Nauka, Moscow, 179 p. [in

Russian).

— 1995. — Triassic ammonites ofthe Northivest

Caueasus. Nauka, Moscow, 1"^4 p. |in Rassianb

Shvanov V. N. 1966. — Lithostraiigraphy and srrac-

uire of the Faurida Formation in the Bodrak River

Basin of the Crimea. Vestrnh Leningradskogo

I[nwersittsa Geologp 6 11 ): 153-156 [in Russian).

Touinansky O. Cj. 1931. — Cephalopoda,

Arnrnonoidea. in The PermO’Carboniferom ueds of

the Crimea Pl. 1. Gcological Survey, I.eningrad-

Mo.scow. 117 p. |in Ru.ssian].

— 1935. — The Pcrmo-C:trbunifcrou.s trilobitcs of

the Crimea, tn The Perrno-Carhonfferous heds ofthe

Crimea. Pt. 2. Geological Survey, Leningrad-

Moscow, 63 p. [iu Russian).

— 193“^a, — La stratigraphie du système Permien

d’apros les -ainmonce.s: 93 [in French), in JJrh

International ^eohgieal Congress^ Moscow. abstract

volume. C'hief Editorial Office. Moscow.

— 1937b. — Les dépôts permiens de Crimée: 108. in

Inicrnationai gei>lt>gtcjl Congress, Mo.scow, abstract

volume (in 1-rcnch] and; 47()-472 [in Russian], in

Problerns ojSoifictgeofogy, fome VIL 5-6.

l'otiniansky O (.i 1941. — K sirangragü pcmi.skikh

otlozhenyi Kryma. Doklady AN USSR f2 (4):

259-262 [in Ru.vsian].

— 1963. — Permian Arnrnonoidea of the Middle

Pamirs and its strarigraphical signiricance. Nauka,

Mixscow, 119 p. [în Russian).

Yilma/. \Tüysü/. O., Yigilcbus I:., Gcnc C. a< Sengôr

A. M. C. 1997. — Gcology and Tcctonic

Evolution of the Pontides, in Robinson A. G. (ed.),

Régional and rVtroleuni Gcology of rhe Black-Sca

iiiul SurmuiKling Région Alt nioir of ihe American

Asmeiation aj Petroleum Geoiogists 68: 183-226.

Zheng M. 1986. — Fhe smalJ foraminifera fauna in

Qixia stage (Early Permian) of Daxiakou, Xingshan

County, Hubei Province. Earrh Science Journal.

Wuhan College oj Gcology ] 1 (4); 489-498.

Submittedjorpuhltcatton on 26 September 1997;

accepted on 30 june 1998.

GEODIVERSITAS • 1999 • 21 (3)

323

Upper Permian and Triassic of the Precaspian

Dépréssion: stratigraphy and palaeogeography

Dmitri A. KUKHTINOV

Palaeontology Department, Faculty of Geology, University of Saratov,

83 Astrakhanian St., Saratov 410071 (Russia)

ccvg @ mail.saratov.ru

Sylvie CRASQUIN-SOLEAU

CNRS, UPRESA 7073, Université Pierre et Marie Curie, Département de Géologie sédimentaire,

T. 15-25, E. 4, case 104, F-75252 Paris cedex 05 (France)

crasquin@ccr.jussieu.fr

Kukhtinov D. A. & Crasquin-Soleau S. 1999. — Upper Permian and Triassic of the

Precaspian Dépréssion: stratigraphy and palaeogeography, in Crasquin-Soleau S. &

De Wever P. (eds), Peri-Telhys: stratigraphie corrélations 3, Geodiversitas 21 (3) : 325-

346.

KEYWORDS

Precaspian Depre.s.sion,

Upper Permian,

T riassic,

stratigraphy,

palaeogeography.

ABSTRACT

The stratigraphie scrie of the Precaspian Dépréssion during the Upper

Permian and the Triassic is analysed. Data from seismic sections and from

numerous boreholes are used. The lithological composition and the palaeon-

tological content are cleared for ail rhe time inrerval. Three palaeogeographi-

cal maps are drawing for che Kazanian, the Lower Triassic and the Mîddle

Triassic. The évolution of palaeoenvironments is restored in relation to the

tectonic events and the fluctuations of the Boréal Sea and the Palaeo-Tethys

Océan.

MOTS CLÉS

Dépression Précaspienne,

Permien supérieur,

Trias,

stratigraphie,

paléogéographie.

RÉSUMÉ

Le Permian supérieur et le Trias de la Dépression Précaspienne : stratigraphie et

paléogéogaphie.

La série stratigraphique de la Dépression Précaspienne est analysée pour le

Permien supérieur et le Trias. Le.s donnée.s de profils sismiques et de nom¬

breux forages sont utilisées. La composition Üihologiquc et le contenu

paléonrologique sont précisés pour l’intervalle de temps considéré. Trois

cartes paléogéographiques sont établies pour le Kazanicn, le Trias inférieur et

le Tria.s moyen. L’évolution de.s paléoenvironnements est établie en relation

avec les événements tectoniques et les fluctuations de la mer Boréale et de

l’océan Paléo-Téthysien.

GEODIVERSITAS • 1999 • 21 (3)

325

Kukhtinov D. A. & Crasquin-Soleau S.

INTRODUCnON

The Uppcr Permian and the Triassic of the

Precaspian Dépréssion and adjacent areas are

represented by marine and continental deposits.

The compicx original rclaiionships becween these

deposits hâve bcen modified by ihe sait tectono-

genesis. The sali dômes are widely distribuied

(Fig. 1 ) and dic uppcr part is oftcii eroded. The

most complété sections are in ihe dépréssions

between the dômes. We présent hcre new data

which complote the previous work (Kukhtinov

1976, 1984) on stratigraphy and deposirional

conditions.

STRATIGRAPHY (Table 1)

The Upper Permian (Pd

The Upper Permian deposits are irregularly stu-

died. They were drllled during the oil and ga.s

prospecting, mainly on rhe borders of the

Dépréssion (Figs 2-5). (n the ceMural part oi ihe

basin, in the Aralsor 1 horchole (localîty 2 on

Figs 6, 7)t the Uppcr Permian succession is rcco-

gnized benveen 6806 and 5492 ni., The base of

the Uppcr Permian is nor reached. The most

complète sequence is located on the easiern bor¬

der of the Dépréssion where ail substages are cha-

racteriscd by lheit palaeontological content

(cxamplc Lugov boreholc. No. 45 on Figs 6, 7).

The UfiTnmii (Put)

In the eastern part of the Dépréssion, two terri-

genous units were rccognised (Fig. 6). The lower

one (Piui) is grey (200-300 m) and has not clear

bovmdarv wicK ihc underlying Kiingurian. Ir is

composed of finc-grained sandstoncs, claystones

and aleurolites — aleurolires is more or Icss équi¬

valent ro silrstone in Riissian üteraiure. The

upper unir (Piu:) i.s red (200-300 m) and is

mainly represented by sandstones, lu both units,

anhydrites and sait lenscs arc someiimcs inter-

layered and typical o.stracod.s of the Darwimtla

angusUi zone from the Russian platform Ufimian

(see for example Molotovskaya 1997) are a-cove-

r e d {D a r tif i n nia ht b imo vue K a s h c v a r o v a,

D. angusta Mandelstam, D. lanzetiforrnis

Kashevarova, D. fainaehcXoxxsowz, D. burajevoen-

sis Palanc. D. cf. trita Paiani, D. cf. pyriformis

Kashevarova). The bivalve Palaeomutiia cf. stego-

cephalum Nechaev, as well as miospores and

conchostraceans> permit the corrélations with the

synchronous deposits of Aktjubian Pre-Uralian

zone.

In ihc central part of the Dépression, the red

argilites and sandstones with inclusions of anhy-

dritc drilled in rhe Aralsor well (6630-6806 m)

are related co the Ufimian (Fig. 6). The thickest

Ufimian deposits (more rhan 581 m) were

drilled in l.injovka S well (locality 43 on Fig. 7)

on the northern edge. They arc composed of

grey and red terrigenous, carbonated and sulfate-

halogcnous rocks with non marine ostracods

(D(irwinubz nhandii Mandelstam, D. acervalis

Mandelstam, D. aff. pnrplH’novae Belousova,

D. sifhaclhns Zhernakova), bivalves (Palaeo-

mutc4a ex gr. ovataeformh Gussev, P. cf. pseii-

doumbanain Gussev, Anthraconaia rhomboïdes

Netschajev), conchostraceans, fishes and charo-

phyres.

In northern and western edges of rhe I3epre.ssion,

chc Ufimian is defined between ihe Kungurian

anhydrites and ihc Kazanian clays and carbo-

iiaiesî 30 to 70 m of red and grey sulphate-ierri-

genous, halogenic and rarely carbonates rocks are

recognised. In rhe south-western part, the

Ufimian terrigenous deposits (63 lo 1242 m) are

disringuished by spores and polleas. The .spore

and pollen .spccira shows prédominance oi snia-

tïti (up Uï 52%) and Viuaiina (27 to 37%).

These deposits arc includcd in the Volozhkov-

skaya suite (wi'ihout subdivision) from Ufimian-

Kazanlan (Pronicheva & Savinova 1982).

The Kitzonuw Stage (Pjkz)

It is represenred by two sut>stagcs (lower and

upper) in moM of îlie Preaispian [Répression and

its northern and western adjacent areas.

Lower Kazanian substage (p2kz,), The

Kalmovskaya suite is composed of clays, dolo¬

mites, liincstones, rarely sandstones with marine

macro- and microfauna' brachiopods \Camrï-

nclia caticrlni Verneuil, Beecheria netsehaevi

Grigorieva, Cleiothyridina reussiana (Keiserling),

C. pectinifera (Sowerby)], bivalves Pseudomonotis

326

GEODIVERSITAS • 1999 • 21 (3)

Upper Permian and Triassic of the Precaspian Dépréssion

45E 55”E

Fig. 1. — Tedonic charl of lhe Precaspian Dépréssion, Tectnnic fealures 1 Akhtubirisk-Palassowski megamound;

2, D 2 hanybeckoe rise; 3. Altatinsk-Nikolskiy mouncJ: 4. Karachaganak-Koblandinskay upltfl; 5, Temirskiy dôme. 6. Kzyloshafskiy

dôme: 7. Zharkamyssiy dôme: 8. Oosaorskiy iroucjh 9 Biikzhalskiy dôme; 10. South Emba uptift: 11. Gunev dôme, 12, Karaton-

Tengiz uplîH; 13. ZhayksKiy dôme; 14, North-Caspian dôme; 15, Akkolskiy dôme; 16, Mynlobinskay uplift 17, Kobyakcvskoe uplift;

18, Octyabrskoe uplitt; 19. Azgirskoe uplift; 20, Astrakan dôme: 21, Suvodskaya uplift: 22. ÛlKhovskay dépréssion; 23. Archedino-

Don mound: 24. Zhirnovsko-Umetuvskiy mound, 25, AntipovsKo-Shefbakovskîy mound 26, Tersinskaya dépréssion: 27. Zolotovsko-

Karnenskaya uplift: 28, KaramyshsKaya uplift. 29, Eishano-Sergievskiy mound; 30, Stepnovskiy mound: 31, Voskeresenskaya

dépréssion; 32. Saratov displacements. 33. Kazanlinskiy monud. 34. Pugachevskiy dôme; 35, Marievskaya upüft, 36, Balakovskaya

uplift; 37, Klinisovskay uplitt; 38. Kamellk-Chaganskiy mound, 39. Zemiyanskiy mound: 40. Syrtovskiy mound,

elengatula Netschujev, Parallelodon kingi Verneuil,

P. cf. strÛHUs (Schlocbeim), Bdmondia elongata

House, BakevcUia (Bakevellia) cerataphaga

(Schlorheim)]i bryozoa \^DyscYitel!a hnrustaia

Morozova]> foraminifcras \Palcieonuhecïdana

uniserialfs Reitlinger, P fîtixa Reiilingcr,

Geinit 7 >Piii pu^illa Grov-dilova. G. spundeti

Tscherdyn/ev, G. cf. postcarbonicti Spandcl,

Nodosarina ehibugae Tschcrdynzcv, TV. netscbevi

Tscherdynzcv, Spandelli)ia ex gr. cordiformis

Gerce], ostracods [Healdia subtriangula

Kotschetkova, U. simplex Roimdy, Healdianelbi

vulgata Kotschetkova, H. parallela Knight, //. ex

gr. osagensis Kellett, H. ex gr. panda

Kotschetkova, Cavelliniû et. univa Kotschetkova,

C. ex gr. edmistonae (Harris & Lalicker)]. The

ihickness varies tram 0 to 168 m.

In elle soiuh-wcstcrn part of the Dépréssion, the

upper Volozhkovskaya suite is composed of red

and grcy terrigenous rocks. In the south, the

Zhambay 22 \yell (nored 3 on Fig. 7) shows

untler the Triassic, terrigenous rocks with bra-

chiopods, pelecypods, ostracods {Danainula sp.,

Mùorea d. fadlis Schneider) of lower Kazanian

substage. In ihc east of the Precaspian Depres-

sion, the séries (700 m), composed oF regularly

interlaid sandscones, aleurolites, argilites and

limestones with locally sait lenses, is synchronous

GEODIVERSITAS • 1999 • 21 (3)

327

Kukhtinov D. A. & Crasquin-Soleau S.

1

STAGE

HORIZON

SERIE

SUITE

West

Centre and North-West

East

T3

Kusankudukian

Tsks

iü

Koktinskaya

T2

■

Chobdian

Tach

Aralsorskaya

Barmantsakskaya

Chobd*nçkava-T;kfi|

J2ak

Sarpinskaya

Akmamykskaya

Masfôksaiskian

Tams

MasleksaisKava

Anisian

Inderlan

Tzin

Akmaiskaya

Taak

Inderiskava

Inderskava

k’MvLcuc. lasshii-skaya

Eltonian

Taei

Eltonskaya

Btonskaya

Tjiw

T1

Otenelyan

Baskuntchakian

Tibs

Zhulidovskaya

Akzharsajskaya

T^kz

Aktubinskaya

Induan

Ershovian

Tier

Prikaspinjskaya

Bugrinskaya

Ershovskaya

Kokzhidinskaya-Tivr

Sorkoiskaya-T’sk

P2

Viatkian

P£vt

Batyrmolinskaya

Viatkian

Severodvlnian

P?5d

Sererodvinian

Urzhmian

P2ut

Urzhumian

mgi

P2kr£

Volozhkovskaya

Upper Kazanian

upper Kazanian

tower Kazanian

Pakzi

Kalinovskaya

Ufimlari

P2u

upper Uflmian

P2u2

Sheshmian

Sheshnnian-P 2 sh

lower Ufimian

P2u1

Solikamian

Soljkamian-P 2 si

Table 1. — Upper Permian and Triassic stratigraphie subdivisions of the Precaspian Dépréssion.

with the Knlinovslayn suite. Tlie organic remains

are crinoid.s, oscrucods (Sinmuella cf. ignoia

Spizharskyi, Darwinula varsaviffievae Belousova,

D. irinae Bclousova, D. i^elica Starojilova.

D. accomodatü StarojUova, D, ex gr. tichivinskaje

Bclousova, Sut'honelU onegi'i Bclousova, S. belehei-

ca Bclousova, S. sacmaremis Starojilova,

Darwimiloide^ ednnstonae Bclousova, D. sentja-

kensis Sharapova, D. iriangida Bclousova), non

marine pelecypods, miospores. Fhey allow the

comparison with the Akjubian (low'cr Kazaniaii

or Kazanian) ot Pre-Ural and Russian platform.

Upper Kazanian substage (P 2 kz 2 ). The upper

Kazanian substage is evcrtwhere represented by

terrigenous rocks. To the east of the Dépréssion,

the sériés is composed of sandstones with conglo-

merate at the boicom and argilitc interbedded

(mainly in the upper part). In this séries (400-

500 m), rhey arc quite often non-marine bivalves

[Palaeomutela ex gr. krotûvi Nechaev, P. ex gr.

doratioformis Gussev, P, ef. iimhonata (Fischer).

P. cf. vjatkensis Gussev, Palaeanodonta rhomboi-

dea (Nechaev)], ostracods [Darwimda varsanofie-

var Bclousova, D. innocurovi Bclousova, D. ncco-

rfiüdiita Starojilova, D, inornalina Bclousova,

D. ulexandripiae Bclousova, Suchonella helebeica

Bclousova, 5. onega Bclousova, 5. snpttLi Belou-

sova, Darwinulüides stntjakensh Sharapova,

D. edniistonae Bclousova. D. tnnnguUt Bclousova,

SinusKcIltt ignota Spizharskyi], spores and pollen

which arc charactcxistic of the whole Kazanian

stage or of its upper substage iu the most areas of

the Russian platlorm.

In tlie centrai part of the Dépression, the upper

Kazanian substage is composed of red aleurolites

and argilites with marine and non-marine ostra-

cüds [Healdia sp., IJealdianelh vulgnta

Kotschetkova, Hmldiandln sp.. Monôcemtinci aff.

exith (Schneider), Schnehierta ex gr. kotschetkovae

Starojilova, Darwinula sp., Snchondta sacnnnensis

Starojilova, 5. Hehwinskaja (Belousova), Ptaddea

sp., Tomielta sp.|. 'fhc thickness rcaches 345 m.

On the northern Dépréssion border, on che

Kidinovskaya suite, the red atgiliies with anhy-

drite and sait inclusions, could be palaeontologî-

cally correlatcd with che upper Kazanian deposits

328

GEODIVERSITAS • 1999 • 21 (3)

SE/W

E/SW

SE/NNW

Kamishin

Nicolaev-Levchunov

Upryamov

34

33

4 3 1

1

Fig. 2, — Geological-geophysical cross section SP 052 (location on Fig. 7). Western margin-Centra) part of Precaspian Dépréssion, PR3A/d. Upper Precambrian-Vendian;

FR, Rtphean; S. Silunan; D. Devonian; DI. Early Devonian; D2. Middie Devonîan; D3. Late Devonian; D3fr. Frasntan; D3f1. early Frasnian; D3f2. middie Frasnian; D3f3. laie

Frasnian: D3fm, Famennian; Cl, Early Carboniferous; C2. Middie Carbontferous. C3. Late Carboniterous; C1t. Tournaisian; C1v. Visean; C1v2. late Visean; C1v3, laie Visean;

C2b1, early Bashkirîan, C2b2, late Bashkirlan: C2m1, early Moscovian; C2m2. late Moscovian: PI. Early Permian; P2. Laie Permian; P1a, Asselian; Pis. Sakmarian;

Plar, Artinskian; Plk, Kungurian; P2kz. Kazanian; T Triasslc; Tl, Early Tnassic: J. Jurassic; K, Cretaceous; K1, Early Cretaceous; K2. Laie Cretaceous; Pal, Palaeogene; N2, laie

Neogene; III. 112.113, the three main dîscontinuilies; F. major fault.

Upper Permian and Triassic of the Precaspian Dépréssion

Kukhtinov D. A. & Crasquin-Soleau S.

of the Orenburg Pre-Ural adjacent area.

In other areas, chère are no data reliable to the

upper Kazanian substage.

The Tatarlan Stage (Pj^)

Lower Tatarian substage (Pat,). In the eavStern

part of the Dépréssion, the lower Tatarian is

represenred by red clays (600-800 m). The osera-

cods are non-marine [Darwinula elongata

Lunjak, D teodorovichi Belousova, D. tichonovi-

chi Belousova, D. (ragtliformh Kashevarova,

D. elegantelln Belousova, D. perlonga Sharapova,

D. torensis Kotschetkova, Sucbouella nasalis

Sharapova, Daywinuloides dohrinkaemis Kashe¬

varova). Sortie non marine pciccypods wcrc

found (Palaeanadopttit mvalis Nechaev, P. ver-

neuili (Amaltisky), P, cf. longissima Nechaev,

P fischeri Amalfisky, Pnlneirmiittda vjatkemis

Gussev, /? plana Amaltisky, Authraemaia sp.,

Microdontella sp.). Spores and pollens confirtn

the stratigraphie attribution.

In the central part, the Arasol well (localicy 2,

Figs 6, 7) présents, in ihe inierval 6045-5875 ni,

red-brovvn aleurolires and argiliies with the non-

marine ostracods {^Darwinidoides djurtjulensis

Palant, Volganellu sp.) atttibuted to the lower

Tatarian.

In the north-western pan of the Dépression, the

sériés is forined of red clays> alcurolites, sand-

stones with anhydrite inclusions. It contains cha-

rophytes froin ihc Taiatian and ostracods from

the lower Tatarian [Darwinula fragiliformis

Kashevarova, Z), elongaia Liinjak, Snchnnella

nasalis Sharapova! and from the upper Tatarian

(Suchonellina inornata Spizharskyi, S. parallela

Spizharskyi, Suihonctla stebnachovi Spi/har.slc)'i).

The thickness varies from 0 to 2030 m. Ourside

of the Dépression, siinilar deposits were obser-

ved, with both substage ostracod assemblages,

and hâve a thickness of 0 to 300 m.

In the sou ch-western part, the red terrigenous

deposits (about 1200 m) are rclaied to the

Tatarian Batyrmolinskaya suite by ihc presence

of spores and pollens (complex j) as well as the

ostracod Sttcbonellirui.

Upper Tatarian substage (^ 2 * 2 )* clearly

defined on the inner border of the ea-Stern part of

the Dépression, where it is represented by sand-

stones and clays (up to 600 m) with ostracods

{Suchonellina inornata Spizharskyi, S. panillela

Spizharskyi, Suchonella stelnuirhom Spizharskyi,

Volgtinella magma Spizharskyi) characteristic of

the North Dvinian horizon and which allow the

corrélations with Southern Urals (Molostovskaya

1907).

In the central parr, in the Aralsor well (58^5-

5492 m) (locality 2 on Figs 6, 7), the upper

Tatarian présents red and grcy sandsrones, aleu-

rolites, argillites and clay maris svith ostracods of

uhc Viatkian horizon (Darwinutoides tataricus

Posncr, D. svijnzhicus Sharapova).

As a wholc, the Upper Permian has not been stu-

died in full. h is mainly represented by red cerri-

genous deposits. which are trnditionally regarded

as continental. In general in Ru.s.sia, ihc lower

Kazanian is marine. On the lOepression periphe-

ry. there are red interbeds with marine fauna.

The maximum thickness of the Upper Permian

is located on eastern and Southern horder.s ol the

Dépression.

Lowhr TlUÂSSic (T,)

The Lower Triassic deposits of the Precaspian

Dépression and its adjacent areas overlay with

unconformity varions Permian levels. In the cen¬

tral part ot fhe Dépréssion, the contact between

Permian and Triassic is not known.

The Lower Triassic corresponds hcrc to chc inter¬

national subdivisions (Induan and Olcneldan). At

the régional scale (Anonymous 1982), it is referred

Lo the Frshovian and Baskunchakian horizons

(Table I).

The Ershovian (T^^J

It is accuraiely defined. It consists of continental

red terrigenous deposits laleurolites, argilites and

rare sandstones; Figs 8. 9) with ostracods

\Darwiniilla ovalis Glebovskaya. D. quadrata

Mischina, D. dubia Starojilova. D. regia

Mischtna, D. ^n?r/y Mischina, D. pseudoinomata

Belousova. D. postparallda Mischina, Gcrdalia

weîliigensis Belou.sova, Snchonella postt)’pica

Stafojilova. S. circula Starojilova, S, rykovi

vStarojilovâ (Darwinula quadrata-D. dubia zone)J,

conchostracans {Vertex/a tauriconis Lutkevich,

Cyclôtungtézites guffa Lurkcvich], charophytes

[Vladirniriella globosa {Sâidâkovsky), V wetlugen-

330

GEODIVERSITAS • 1999 • 21 (3)

i\\ni:iinn»sisffli

SW/NW

SE/N

S/NW

SE/NNE

SSW/NE

Stepnov

Lubimov

Erusian

Karpen

Vladimirov

Timofeev

101 33

20 19 15 5 8

3 2

4 20 519 7

19 14

2

1

Wm

îi:>;j\^. I j>ik+P2k|_ A '

^^♦02+n^^'

— C2b+m1

jmî

Fig. 3. — Geological-geophysical cross section GG 07 (location on Fig. 7). North-western margin-central part of Precaspian Dépréssion. Legend: see Fig. 2

Kukhtinov D. A. & Crasquin-Soleau S.

i-zV SaidakovskyK spores and pollen.

Vertexia îatiricornis are aiso kjiown in dcposits of

middle parr of the Vetluzlikaya séries of the

Moscow syncline, tlie Kopanskaya suite of the

Volgo-Ural anticline, in the niiddlc part of the

Korenevskaya suite of the Prypiat trough ot the

Russian platform and in lower variegated sand-

stone in Germany (Nordhausen and Bernburg

suites).

In the eascern part of the Dépréssion (Blacktykol

well; lotaliry 46 on Figs H, 10)j the

Blacktykolskaya, Sorkolskaya and Kokzhidin-

skaya suites are clearly ideniified. The

Blacktykolskaya suite (maximum ut tliickness

90 m) overlics with unconlormity the Permian.

It begins by a conglomerare Icvel following by

sandstoncs and clays. To the cast, rhis suite is

absent and the Sorkolskaya suite lies on the

Permian (Kenkiyak well; loeality 44 on Figs 8,

10) with a maximum tliickness oi 87 m. The

Kokzhidinskaya suite Table 1; up to

140 m) is composed of clay sandsrones with clay

interbeds.

In others areas, the Ershovian horizon is undiffe-

rentiated, with red sandy clay deposits. The

thickne.ss varies front 0 to 340 m.

The Baskunchakuni (

This horizon combines the marine deposits of

the Baskunchakian suite (Table 1) and its conti¬

nental analogue. In Bolshoi Bogdo Mountain

(the only outaop in the area) four suites (West

in Table 1) arc distinguished.

The Busulukskaya suite. 96 ni of red and grey

sandstones without organic rcmains.

The Akhtubinskaya suite. 64 m ot red aleiiroli-

te clays with numeious lossUs.

Charophytes: Porochara triassicit (Saidakovsky).

Ostracods: Clinocypris trias^iai (Schneider),

C. elongata (Schneider), Darwinula oblonga

Schneider, Gerdalui longa Beluiisova.

Co n c h os t ra ce a n s : Cyclotu nguzites gutta

(Ltitkevich), Lioesthena Novojilov.

Ichtyofauna; Csnathorhiza trlassicii haskuntschU’

kensis h'linich, C7. bogdoemis Minich, G. otschevî

Minich, CenUodui rnnUicrislatus feodorensis

Minich (sec also Minikli & Minlkli 1997).

Bivalves: Bakewellia lipatovae Kiparisova.

The Bogdoninskaya suite. 24 to 100 m of

variegated clays following by grcy clays with

limestoues interbedded.

Ccpbalopods: TiroUtes cassietnus (Quenstedt),

Dorikranites bogdounus (Buch.), D. acutus

(Mojsisovich).

Pelecypods: Mytilui tuarkyrensis Kiparisova,

Myijl'ma dakilamae (Verneuil), Unionites fassaen-

sis (Wis.smann), U. canalerisis (Catullo).

Brachiopods: Lingula.

letrapods: Parotosuchus bogdoamis S. Woodward.

Fishes; Cemtodus midticriUatus mxdticrhtatus

Minich, Gnathorïza triassica haskuntchûkensis

Minich, G. bogdemis Minich.

Ostracods; TriassinelLi chramovi Schneider,

Clinùiypri> cognata Siarojilova, C couferta

Starojilova, C. oleneca Kukhtinov, Darwinula

mîundnta Luber, D. parm Schneider, D, nota

Schneider, D. acuta Mischina, Gerdalia dactyla

Bclousova, Uogdoella delicata (Starojilova),

B. antiqua Starujilora.

Charophyces: various Porochara and lot the first

rime Auerbachichara.

Conodonis, conchostracans, plants, spores and

pollen.

The Enotajevskaya suite. 57 m of grey and

variegated sand-clays with charophytes

{Porochara Vladimirella) and ostracods domi-

nared by Gerdalia {Gerdalia dactyla zone).

Laterally chc Alchtubinskaya and Bogdiiiskaya

suites (Table 1) arc gcncrally combined in a clay

unit ol 400 m rhick. On the eastem border, the

Ak/arsajskaya suite ovciiays it in contormity and

is rq^resented by red sand clays up to 150 ni. On

the üuter edges, to ihe rtorth, the Krasnokut-

skaya suite consisted of sandsrones following by

cUys (273 m) and to the west the Berezovskaya

and Lipovskayâ (or only Lipovskaya) suites (0-

256 m) arc transgressive and overlay the Permian

or Upper Carbonilerous. Ail thèse suites arc

referred to the Baskunchakian horizon.

The corrélations could be well-cstablished bet-

ween Ba.skunchakian horizon and synchronous

deposits of the Russian Platform by fishes

(Minikh & Minikh 1997). l'he fauna of

Payoîostichus is found also in the sections of

Volgo-Uralian anticline, Preuralian and Pripyat

throughs, Moscow and Mezensk synclines and in

332

GEODIVERSITAS • 1999 • 21 (3)

Fig. 4. — Geological-geophysical cross section GG 051 (location on Fig. 7). South-eastern part of Precaspian Dépréssion. Legend: see Fig. 2.

U)

fpper Permian and Triassic of the Precaspian Dépréssion

Kukhtinov D. A. & Crasquin-Soleau S.

the variegared sandstone of German basin. The

ammonites Dorikranitcs and TiroHtes allow to

correlate wirh the upper Olenekian ofRussia and

with the Campile beds o( Alpine Triassic and the

Spathian Tirolites zone (Shevyrev 1990).

Middlf Trtassic (T^)

The Akmajskaya and the lower Aralsordkaya

sériés are artributed to the Middle Triassic

(Table l).

The Akmajskaya séries

It is distribured in most part of the Precaspian

Dépréssion. The basal boundary is marked by

the change of the Baskunchakian clay in the

sandstones of the Middle Triassic. Two suites are

recogniscd: the Eltonskaya and the Inderskaya

(Fig. 9).

The Eltonskaya suite (T2ei). le begins with

sandstones follovved by clays and limestones. fhe

total thickness varies from 100 to 400 m.

The lowci part, terrigenous, contains the transi-

tional complex with mainly l.owcr Triassic .spc-

cies and lew' Middle Triassic species {Dartvinula

recondita Schleifer, D, Ltuta Schleifer, D. acmayi-

ca Schleifer, D. postinornata Schleifer, Suchonella

flexuosa Starojilova Irom ihe Dutwwula lanta

zone).

The upper part, clay and carbonates, is typical

from the Middle Triassic (iMtkevichinella involn-

ta Schneider, L bmttanae Schneider, L. minora

Starojilova, Pulvivlla iwalis Schneider, Trkminella

^ubkini Schleifer, (2hrocypris vasilievi Schleifer,

forming ihc LutkevichineUa brunanae zone).

The Eltonskaya suite contains tetrapods as

Plagioseutum ochevi Shishkin, Capitosauridae,

referring to L'ryosUi’htft w^hich is wcll correlated

with fauna of Central Europe (Shishkin &

Ochev 1992).

The Inderskaya suite (Tjj^). It présents clays

and carbonates on a thickness ot 100 to 250 m.

Both suites (Eltonskaya and Inderskaya) are cha-

racterised by a single Middle Triassic Darwinu-

locopida ostracods assemblage (DarwinuLt obesa

Schleifer, D. kiptschakensis SchleOer, D. lenta

Schleifer, D. lanta Schleifer, D. recondita

Schleifer, D. acmayica Schleifer) but by diHerent

Cytherocopina ostracod assemblages. In the

lower suite, there are Gloridnella inderica

Schleifer, Renngarte7iella distinvia Starojilova,

Cytherissinella orispa Schleifer from the

Glorianellcl inderica zone. Tn the upper .suite, the

tollowing species Irum the Pulvielht aralsofica

zone occur: Pulinelh aralsoriça Schleifer, P obola

Schleifer, P. lubimovae Schleifer, P, directa

Starojilova, P marimie Starojilova, Speluncelia

auerbachi Schleifer, .S. spiriosa Schneider,

Inderelln usimica Schleifer, Aralsorella uralica

Scldcifer. Moreover, there are bivalves and ga.stro-

pods Lhiionites fassaensis (Wissmann), (/. rriuens-

teri (Wissmann), Cryptunerita elliptica Kittl,

Actaeonina mediuculcis Ilohensiein, vcftebrares

Mtistodmnaurîis torims Konzhukuva, Plapoicutam

caspiense Shishkin, which allow the corrélation

with the lower Kcuper of the Central Europe

(Shishkin Ôc Ochev 1992).

To the south-w'estern part of the Dépréssion, the

.\kmajskaya sériés présents mainly clays and the

thickness groAvs up to 1200 m. To the west, on

the borders, ic changes in variegated terrigenous

deposits of chc Morovovskaya suite (275 m) with

charophyres, ostracods and in some layers

Cytherocopina of Inderskaya suite. To the cast,

the Akmajskaya suite is complerely replaced by

the variegated .sand-clay Ta-shtiskaya suite (l'zts;

230 m; Fig. 3) whh charactcrisdc non-marine

ostracods and charophyres. Outside of the

Depression to the north and to the east, the

Middle Tna.ssic is mlssing.

The Arahnrskaya p.p.

This sériés contains grey to variegated terrige¬

nous and calcareous deposits from Middle and

Upper Triassic (Figs 1 T 12). The Lower Jurassic

Re.sobinskaya suite overlays it with important

uncorformity (Shclcchova et al. 1989). The

Aralsorian is subdivided in six suites:

Masteksajskaya, Almamyskaya, Chodinskaya (the

three from rhe Middle Triassic), Koktinskaya,

Shalkarskaya and Kusankudukaya (the three

from the Llpper'rfia.ssic).

The Masteksajskaya suite (T2„,j). h is compo-

sed of grey to Black clays, aleurolites, rarely sand¬

stones and limestones (210 m). Il overlies the

Akmajskian sériés {Pulviella araLoria zone). Its

red analogous deposits extend to the east through

334

GEODIVERSITAS • 1999 • 21 (3)

Kukhtinov D. A. & Crasquin-Soleau S.

the boundaries of rhc Dépréssion to chc DoneU

Through and the Prc-Ural. l'he suirc is characre-

rised by a rich ostracod assemblage where the

species known in the undcrlying levels

{Darwinuln laMta SchJcifèrr, D. oheîû Schleifer,

D. inféra SchJeifer, D. kiptschakensis Schleifer,

Pulviella araborica Schlcifcr, P. ohola Schleifer,

P. directa StarojÜova, Spelnncella spinosa

Schneider) arc associated with spccics occurring

for the tirst time {Gemmanetla schweyeri

Schneider, G. magtna Ko/.ur. G. grammi Kozur,

G. rnovsrhovichi Kozur, G’, densistriata Kozur,

G. meyevi Ko/.ur, G. tuberculata Schleifer,

Spelnncella ascedens Diebel, Cytherissinella okra-

jantei Schleifer, C. wkoloaae Schneider,

GlorianeUa efforrn (Glebovskaya), G. mtriovae

Schneider. Renngartenelln anerbadn Schneider,

Casachstanella shungayica Schleifer, Telocythere

fischeri Kozur, Luthevichiriella pseudopusilla

Kozur].

The Almamy.skaya suite It is represented

by grey and variegated rerrigenous rocks (0 ro

425 m) wich Middlc Triassic ostracods (Gernnui-

nella schweyeri Schneider,. Pulviella ovalis

Schneider, Spelnncella spinosa Schneider, S. f/e-

gans (Bturler & Grund), GlorianeUa mirtovae

Schneider» G. ejforta (Glebovskaya), Retingarte-

nelLt avdtmni Schncidci, Cytherissinella okrajant-

ci Schneider, C cf elongata Schneider, Casachs¬

tanella shungnyica Schleifer, Darwinubi sp.) and

miospores.

The Chodinskay^ suite (T,^^). It is dlvided in

rwo parts (Shclechova et al. 1988). The lower

parc is massive (Khodlnskaya s.s.) and the upper

part, which lies with uncnnformiry, is the

Khodinsicaya siiiic. In the west, the Barmanrsak'

skaya suite (Movshovich 1994) is équivalent to

the Khodlnskaya suite jr.r. These sutte.s are com-

posed of grcy and variegated clay, with inrerbeds

of aleuroliresv sandsuïnes with siderire concré¬

tions and végétal crumbs. In the norrh-easr of

the Dépréssion, there are some coal incerlayers.

The thickness varies from 0 to 304 m. In the

Barmantsakian suite, there are Middie Triassic

ostracods (Cytherissinella schleiferae Starojilova,

Darwinula acrnayica Schleifer, Suchonella ex gr.

flexuosa Starojilova, Spelnncella ex gr. spinosa

Schneider, S. ex gr. alata levis Kozur), as well as

foraminiferas and charophytes. It can be note

a

Fig. 6. — The Uppçr Permian ot the Precaspian Dépréssion

iilustrated by some représentative borehoies (Lugovskaya 1,45

on Fig. 7; Aralsor 1. 2 on Fig. 7: Vetelkin 8. 1 on Fig. 7).

Legende: a, sand, sandstone; b. siltstone; c, shale; d, limesto-

ne’ e, anhydrite; f, sait; g, carbonated shale: h, coal; î, red

rocks, j. number of borehotes on palaeogeographic maps

(Figs?, 10.12).

chat Speltincclla alata levis is relaied ro the

German basin ac the top of upper ceraricic beds

(Ladinian) (Kozur 1973).

The only section of rhc Aralsorian Middie Tnassic

sériés is presenr in the Zaburunian trough in the

South of the Dépréssion where 1200 m of sand-

clay deposits with some interbeds of limcstones

[with ostracods as well as pelecypods Triganodus

336

GEODIVERSITAS • 1999 • 21 (3)

Upper Permian and Triassic of the Precaspian Dépréssion

50‘E 55‘E

45°E 50°E 55“E 57°E

b

---- - C

+ + d

★ e

0 f

0 g

^ h

I (J |i

cr3o j

Cb k

c8 I

@ m

Ar n

l-^lo

P

• • • q

■ r

ü s

^ t

845 ^

- U

V

Fig. 7. — Kazanian liîhologicaJ and palaeogeographical schéma of the Precaspian Dépréssion. A. alluvial plain episodically floocîed

by the sea; B, C, area o* marine (during lower Kazanian-kzl} and lacustTine (during upper Kazanian-kzS) carbünate clasüc (B) and

salty carbonate (C) déposas. Legend forait the paJaeogeograph^c maps: a, carbonates; b, shtles, c. sandstones: d. sali, e, reddlng:

f. marine ostracods, g, non-manns osiracods; h. pelecypods; (, cephalopods; j. fishes; k. brachiopods; I, foraminiferas; m. charo-

phytes; n, vertebrates; o. Precaspian Basin boundaries; p, limits of lithological-paiaeogeographical domains, q, liants of recent depo-

sil abundance; r. borenoles: s. boreholes fîgured on figs 6. 8, 9. 11; l. number of boreholes {in the upper part number of the

borehote; in the lower pari, in Italie, ihickness) u, c;oss section of Figs 2>5; v. direction of detriticai supplies, List ot boreholes;

1, Vetekin; 2, Aralsor; 3. Zhambay ; 4. Sambay , 5, Karabulak ; 6, Kokzhide ; 7, Mujunkum ; 8. Kulsary ; 43, Linevka , 45. Lugov.

(?) praelongus Kiparisova, T. sandbergeri sand-clay deposics (0-124 m) in the Aralsor,

Schafljaeîitlia silesiaca Assmann, Myophoriopsis Kusankuduk and Prorvin troughs (rcspectively

gyrgaroides {V\\\\\pŸ\)\ are drilled. central, eastern and south-castern parts of rhe

Dépréssion; Table J, Fig. 11). Shclechova (1988)

Upper TkiasSIC (T 3 ) = AkALSORSKAVA SERIESyï.y». described rwo palyno-complex Chasmatosporhes-

The Kôktinskaya, Shalkar^kaya and Kusankuduk- Podosporhes and Camarozanosporites’Gibeospo-

skaya suites rites. The first onc is dcscribcd in the transi üonal

The Upper Triassic part of the Aralsorskaya sériés interval of Middie-Upper Triassic and the second

lies with unconformity on Triassic or Permian. is characterîstic of the middle and upper Keuper

The Kôktinskaya suite (T 3 |j^), It is composed of of the German Basin, the Carnian-Rhaetian

GEODIVERSITAS • 1999 • 21 (3)

337

Kukhtinov D. A. & Crasquin-Soleau S.

Fig. 8. — The Lower and Middie Triassic of the Precaspian Dépréssion illustrated by some représentative boreholes (Kenkiyak 14,

44 on Fig. 12; Blaktykol 1,46 on Fig. 12; Inder 4, 40 on Fig. 12; Skar-Tsaryn 1,48 on Fig. 12). Legend: see Fig. 6.

338

GEODIVERSITAS • 1999 * 21 (3)

Upper Permian and Trtassic of the Precaspian Dépréssion

deposits oi the Eascern Alps, Caucasus and

Donbas (Shelechova et ai 1988).

The Shalkarskaya suite (T 3 ^jj), le ha,s also a sandy

clay composition (Table U Eig. 11). Sandstones

predominate In the lowcr part and clays in the

upper part. The chickness varies from 0 (area bet-

ween the Lirai and Volga rivers, western and nor-

thern borderlands of the Dépréssion) to 84-228 m

to the east. Diftbrein fossils are recognised: Icaf-

prints of Clathropteris mcfuscoides Brongniart

(Carnian-Liassic) and palyno-complex

Neoraismckla taykmi-ijiheosporites (C'arnian), Late

Triassic conchostracans Lioestheria kido't

(Kobayshi), ihimamurat (Kobayshi),

Pscudfstheriti (SphiUropùs) îanii (Kobayslii), P. tur-

kcstanii'a Novojilov àC Kapelku» P gissaric^f

Novojilov & Kapelka, Splhfewtheri/î koreana

(Ozawa 6c Watanabe)» CJfypfoasftimta mniygenica

Novojilov 6c Kapelk.a, Laxomicmglypta kobaynshi

Novojilov 6c Kapelka, Liynmîdin gontsharnvi

Kapelka, Liogj’apu r/î;?r/;/£7ïî« Novojilov.

The Kusankudukskaya suite (T^j^^). It is com-

posed of sandstones, aleurolircs, clays, mainly

grey with somc layers rcaching 12-16 m (Table !,

Fig. 11). The total thickness is 0-300 m. The

Rhaerian age of rhe suite is clearly esiablished on

miospores (Kukhtinuv 1984): présence at the

bottom ol Zehrasporiîes laevigaïus Schcicchova,

Z. interstripiiis (Tbiergart) Klaus, vvhich arc

usually absent in Noriaii. The NorianTUiactian

palyno-complex Kyrîomhporites-Ztbrüsporitts is

described by Schcicchova et al. (1988). These

authors showed rhat the Kusankudukskaya suite

is absent in rhe uUra-deep Aralsor wcll (Fig. 4),

in the central part ol the Dépréssion. So, ir

appears that the Kusankudukskaya suite and the

Upper Triassic are absent from the mosi part of

the western half of the Dépréssion. Between the

Ural and Emba nvers lower courses (Kukheinov

1984), the Middie Triassic pan of rhe Aral-

sorskaya sériés is missing and the Akniajskaya

sériés (or Older Triassic) are overlay by Upper

Triassic (about 220 m). Here, the Pcrmo-Triassic

sériés is more tectonically deformed th;in in other

areas of rhe Depres'sion. To the south (Prorva

area) the analogues of rhe Akmajskaya hâve

important thickness (to 407 m). more rcgular

structure and display maris wlchin sandy clays.

Outside of the Dépréssion, to the north, to the

West and to the east, the Akmajskaya sériés is not

subdivided as well as the underlying Akmajskaya

séries. The overlying Jurassic begins here only in

the middie Bajocian.

PALAEOGEOGRAPHY OF THE

PRECASPIAN DEPRESSION DURING

LATE PERMIAN AND TRIASSIC

We are looking here to the Precaspian

Dépréssion and Jts adjacent areas, l'his territory

is located at the south-castem pan of the Russian

platform bordered by the Uralian and Donets-

UstjLirt Hcrcynidcs. The palacogcography is

controlicd by icctonic and climatic changes

(from high and dunng the Kungurian, to arid

during the Late Permian and Early Triassic and

humid during Middle-Latc Tria.ssic). The gro-

wing ol sait doinc.ç during ihc Llfimian lias signi-

Ficant inOucnce on the deposionai conditions.

Taking In accouni all the sections of rhe Upper

Permian in the south and east of the basin, there

is no signiFicant lirhological changes at the serie.s

bouudaries.

The base of rhe Ufimian is represenred by grey

sédiments. The red coloration increases Utile by

littlc when wc going up in the serie.s. The présen¬

ce of sulphatc inclusions and of halogenous rocks

(in sonie places) can bc attributed to the deve¬

lopment of chc Ufimian basin and residual sait

lakes; the geoclicmi.stry of the Kungurian and

Llfimian (Solikamian) are very .similar

(Kukhtinov 1984). The main change occurs

during .Sheshmian. The progressive disappearan-

ce of chc Kungurian sali-bearing sea lakcs place.

The présence of grey sédiments, végétal débris

and autigenic pyrite prove rhe restorarion of nor¬

mal depositional environments.

The Lirais is the basic source of débris, The

débris sîze and saiid fraction content of the rocks

increase to the east (Dmirrievskij 1966). The

minerai composition of rhe Upper Permian

derriral fractions is characterised by feldspathic

graywakc association and is represented by quartz

(20-35%). feldspar (15-32%), fragments of effu-

sivc and carbonate.s rocks (45-48%) and rarely of

metamorphic rocks (2-5%). In the central part of

the basin, the quartz content increases.

GEODIVERSITAS • 1999 • 21 (3)

339

Kukhtinov D. A. & Crasquin-Soleau S.

Fig. 9. — The Lower Triassic of the Precaspian Dépréssion illustrated by sortie représentative boreholes (Aralsor 1, 2 on Fig. 10;

Kurilov 1,9 on Fig. 10; South Ershov 5, 37 on Fig. 10; Erulsan 5, 42 on Fig. 10). Legend: see Fig. 6.

340

GEODIVERSITAS • 1999 • 21 (3)

Upper Permian and Triassic of the Precaspian Dépréssion

50'E 55“E

Fig. 10. — Lower Triassic Ilthological and palaeogeographlcal schéma of the Precaspian Dépression. A. area of alluvial and proluvial

deposits; B. alluvial plaln, flooded episodlcally by the sea; C. epicontinental marine deposits, Legend: see Fig. 7. List of boreholes:

2. Aralsor; 3, Zhambay; 5. Karabulak; 8. Kulsary; 9, Kurilov; 10, Sadovaya: 11, Bugrin; 12. Stepnov; 13, Zavolzh; 14, Ushtobe;

16, Chinarev; 17. Mertvye Soli; 10, Akzhar; 19, Tuskum, 21, Nikolaev; 22, Podgornen; 37, Ershov; 40, Inder; 42. Erusian:

44, Kenkiyak; 46, Biakiykol; 48, Shar-Tsaryn.

The second half of the Ufimian is defined by the

accumulation of red sédiments. The red colora¬

tion is conditioned by incrcasc ot aridiry entails

by wide development of red eluviuni sédiments

enriched în ferrigenous pigment, l'his is the

resulr of Fe déposition in clay minerais of mont-

morillonite and illite groiips The hydration

degrcc oF Ferrie oxides and lhe intensiry oF ochre

increasing in cluvium are dcfmcd by tempéra¬

ture. It is not accidentaliy iF the red coloration is

developed in the arid stcppe.s and desert areas of

Kazakhstan and develop a hrown coloration lo

the north. The coloration of rodes is defined by

the Fe^*/Fe^* ratio (Janov 1956): with a value up

to 3 it is red-brown to brown-red, berween 1.6

and 3 it is violet to rcd-brick, lower than 1.6 it is

green-grey to grey, 0 is black.

Probably in the basin sédimentation, prédomi¬

nance of oxidation conditions contributes to the

préservation or subséquent increase of red colora¬

tion in the sédiments. The oxidation conditions

are confirmed by the low content of organic

remains. The non marine bivalves and ostr.icods

(Darwinulacea, which arc rcprc.seinative ol 2-

3 m water deep. no more than 10 m) give évi¬

dence of the ba.sin .shallowness. On shorc areas,

in esruaries, ilic colonial algae (cyanophyceae)

wide development in Akeubinsk Fre-Ural and

probably in Precaspian Dépréssion proves this

assessment. In the miospore complex, the alloch-

tonous éléments corne from etmifers grown on

the high lands.

During the Ufimian, the uplifi of de.struction

areas and the development of sait dômes begin in

the trough. At the same time, in che dépréssions

between the sait dômes, syn-sedimentary lakes

appear quire often, due to che washing of sait by

underground waters. Such sédimentation rakes

place now in Inder Lake. The sédimentation in

GEODIVERSITAS • 1999 • 21 (3)

341

Kukhtinov D. A. & Crasquin-Soleau S.

E

W-NW SE

@ ®

Chobda 1 Kusankuduk 35 Aralsor 1 E. Prorva 77

Fig. 11. — The Middie and Upper Triassic (Aralsorskaya suite) of the Precaspian Dépréssion illustrated by some représentative

boreholes (Chobda 1, 32 on Fig. 12; Kusankuduk 35, 34 on Fig. 12; Aralsor 1, 2 on Fig. 12; East Prorva 77, 47 on Fig. 12). Legend:

see Fig. 6.

the basin is controlled by différence between

heightening zones (dômes) and trough zones

(between dômes).

The Kazanîan (Fig. 7) begins with the boréal sea

transgression which follows rhe Urals to reach

the norihern Precaspian territory. Fhin mainly

carbonated rocks with shallow marine fauna

(foraminifera, osiracods» bivalves, bryozoas, ...)

are developcd in the western, central and lesser in

the eastern parts of the Dépréssion. In the south

(Zhambaj area) the sédiments are represented by

interbedding red and grey terrigenoas sédiments

with somc marine rcmains. The analogous rocks

with marine ostracods were detected between

Volga and Ural rivets (Aralsor well). The terrige-

nous material cornes from the south, from

Karpinski uplift and its eastern extension, and

hinders rhe carbonate development. From time

to time, the sca sirctchcs far to the east, to

Kenkijak and Makat (South Emba). Between red

rocks, the inrerbeds of grey sédiments contain

foraminifera, crinoids and radiolarians

(Kukhtinov 1984).

In the eastern part of the Dépréssion, as far as its

présent boundary, an alluvial plain spreads out

and, from time to time, is flooded by the sea. A

thick sequence of aleuroüte and argilite which

contains only one bed of limcstonc, corresponds

hcre lo the marine Ümestonc deposits. Fine dctritic

marcrial is accumulared in the lake.s without flow.

During the Late Kazanian, the régression is cau-

sed by the Uraliun orogenic moveincrits. I he late

Kazanian succession is composed of terrigenous

342

GEODIVERSriAS • 1999 • 21 (3)

Upper Permian and Triassic of the Precaspîan Dépréssion

50’E 55"E

Fig. 12. — Upper Triassic llthological and palaeogeographical scheme of the Precaspian Dépréssion. A, alluvial piain, flooded episo-

dically by the sea; B. C, carbonate>clastic (B) and clastiC'Carbonale (C) deposits of shallow epicontinental sea. Legend: see Fig. 7.

List of boreholes: 1. Vetekin: 2, Aralsor; 3, Zhambay; 5. Karabulak; 10. Sadovaya: 17. Mertvye Soli; 24, Jusa; 25. Zhanazhol;

26, Chikembay; 27. Mashiy; 28. Suishbek; 29, Chumyshty: 31, Zhu&alysay; 32. Chobda; 33, Matenkozka; 34, Kusankuduk;

35. Pavlov; 36. Teplov; 37, Ershov: 38, Shungay; 39. Novonikol; 40, Inder; 41. Shubarkuduk; 47, East Prorva.

sédiments with coarse dctrirics including gric-

stones and conglomérâtes. These last ones are

especially characterisric from the areas siirround-

ing the dômes.

In the residual \vater réservoirs of northern and

western parts of the Dépréssion, rerrigenous sul-

phates and halogenous sédiments are accumula-

ted. in other areas, the sédimentation is

terrigenous with alluviah lacustrine and deltaic

accumulations.

The continental basins contain a rich fauna of

crustaceans and bivalves and numerous algae

which characterise shallow environment. The

salinity is no negligible judging ro the Sr/Ba rario

equal to 2.3.

The total thickness of the Kazanian (about

1200 m) on the eastern pan of the Dépréssion

shows thaï U large trough is présent, compensa-

ted by detritic material from the lirais,

Mugodzhar and South-Emba uplifts.

The Tatarian is characterised by continental

environments. The alluvial North Caspian piain

sinks slowly and is filled by sédiments from lakes,

rivers and temporal water streams. The Sr/Ba

ratio falls from 2.3 to l.3'l-l, this is typical an

indicaror of brackish water. Major inhabirant.s

are non marine pelecypods, ostracods, algae (cha-

rophytes, red, brown, bushy cyanophyceae). The

shallow basins are often dried (présence ot mud

cracks). The frequent cross-beddings arc charac-

teristic of the active hydrodynamic régime. The

dôme arc eroded. Remains of Kungurian ânhy-

dritc are présent in the carly Tatarian sériés. In

some places, especially in the south ol Aktubinsk

Pre-Ural area^ the lake deposits are common —

chemogenic Hmestones, clay with abundant

organic matrer. There are numeroas charophytes

and small fauna of bivalves.

A proluvial piain spreads out along the Urals area

destruction. Detritical fan of temporal flows

GEODIVERSITAS • 1999 * 21 (3)

343

Kukhtinov D. A. & Crasquin-Soleau S.

reaches thc Shubarkuduk area, cspccially during

the late Tatarian. Cross-bedded sandstonefi of

channel and delta types are developed in

Kenkiiak and Mortuk areas, ’l'he intraformatio-

nal washing <uit of the lararian is an indication

of sédimentation above the basis ol érosion (ncar

dôme area), l'hc fine graincd .sand-alcurolite and

pelitic material arc accumulatcd in the lakes of

the central areas.

In the surrounding emerged Innds, there is an

almost constant uplift which indutes an intensi¬

fication of érosion and formation of frequent

interbeds of detriîic material. It obviousiy cakes

place during Severodvinian when coarse detriti-

cal deposits begin to be widely distributed.

At the end of die Permian, rhe eastern and South¬

ern areas of the Dépréssion are învolved in the

uplift which entails érosion of accumulatcd sédi¬

ments and induces rhe unconformity of the

Triassic on the Permian.

At the beginning of rhe Triassic (Fig. 10), thc

sédimentation area is considerably smaller than

the Permian one. In fact rhe structure of the sédi¬

mentation basin cbanged: in the early stages, the

major sedimentary layers were locared in the easr-

ern parc, lacer rhey are concentrated in the cen¬

tral part of the Dépression. The eastern,

Southern, sourh-western and probably northern

peripheral pans of the Precaspian Dépression

were considerably uplifred and represenr a baring

area. The Tatarian and, someiinies in the .sourh

rhe Kazanian rocks were washed oui. At the same

lime, the central pari of thc basin vvas noi inver-

tcd. This is why thc unconformity docs occur

between Permian and Triassic on the borders.

Slowly, the expansion of the sédimentation basin

takes place. The présence of conglomérâtes and

cross-bedded sandscones in the eastern and

south-eastern parts of thc Dépression is duc to

the development of alluvial and proluvial depo¬

sits, step by step cransformed into submarinc-

deltaic and lake deposits (Dmittijevskij &C

Proshljakuv 1970). In thc eastern part of thc

Dépréssion, ehannel flows, in thc a sublatitudinal

direction, eut (Mortuk, Kenkijak, Kokshide) or

walk around (Shengelshij) thc dômes which are

uplifted (Pronicheva & Savinova 1980). When

thc dômes arc cutting, a wide development of

coarse deiritics rocks probably causcd by the for¬

mation of a hlind delta is ob.scrvcd. On the

whole a piedmont-(an type of detrital material

distribution is nianifestcd in this area,

in thc central régions, thc deposits arc represen-

ted mainly by finc-graincd sands, more oficn by

alcurolites and pciites duc to the multiple rede-

positiuns and transfers during rhat rime.

Therefore, the rocks hâve high mineralogical

(quartz and feldspar cornent reaches 80-90%)

and textural maturity.

The Harly ’lriassic deposits bave a high content

of epidote in beavy fraction Corning froni the

érosion of metamorphic rocks of Dral and

Mugod'/har, following by a rapid burying.

The water réservoirs are mainly fresh water

(St/Ba = 0.7 - Demehuk étal. 1971) with charo-

phyies, osiracods and other crustacean. The pré¬

sence of mud-cracks, worm accîvity cracks, and

other emphasise the shallowncss. Dépressions

with lack of drainage and sait lake types were

well developed.

From the Olenekian, a clear change in climatic

conditions cakes place. The transgression coming

from rhe south, i.e. from Caucasus and IVthys,

induces an increasing of the humidity. The sea

envers rhe south-western pan of the Dépression;

from lime to lime it widens its boundaries down

to ihe Southern periphery and Biikjal, in the east

(Fig. 10). Al this time, carbonate and sandy clay

sedimentvS accumulared here. At fir.st, thc basin is

connected with fethys and ic contains tiormal

marine fauna — brachiopods, ammonoids. fora-

minileras. conodontSv fishes, ostricods with

généra of Cypridacea and Cytheracea (C/hio-

ry/j/vj, Spifwcyprh and espcciall)' TMssinella). In

thc South, the ostxacods Bairdia, Bairdiacyprh

and ticaldianellci arc very comnion. In other

times, thc basin bas poor connections with the

océan. The basin is a slightiy salted one (Sr/Ba =

0.9). The fauna is represeuted by ostracods,

bivalves, gastropods, worms, ilshes and charo-

phytes. Along the coasts, the xcrophytes of

Pleitromtia and lycopodiacea type are growing.

The coast lands are flat-hiily plain, alluvial and

proluvial sédiments seule. Close to the desrruc-

344

GEODIVERSITAS • 1999 • 21 (3)

Upper Permian and Triassic of the Precaspian Dépréssion

don areas, coarser deposirs occur on a piedmont

pluin. The detrical marenal cornes from che éro¬

sion of lirais to the east and from the Voronesh

anticline and the Doners fbld sysrem to the west

and to the souih (Movshovich 1977; Janochkina

& Startsev 1977). The upward sait dômes oF

Upper Permian arc additional source rocks. In

Baskunchak and Inder Lakes area, there are rela-

tively coarse deposits formed by drag flows

(Movshovicli & T^ebenko 1974). The syn-

sedimentary uplift of dômes leads to the change

ol the erosional bases and ro intraformarional

washing out in the sections. The tracks as pebble

gravel lenscs occur espccially offert in the upper

part ol the Bashkuchakian sériés.

Eolian formations are présent in rhe Early

Triassic deposits: in sandstones and clays, the

quartz grains hâve characteristic blunr surface

and striations.

Sandstones and aleurolires wich bad granulométrie

sorting and heterogenciry of fragmcncary grain.s

.iTC due to the dilfcrcnt sources ol érosion mate-

rial. The présence of wcll-presetvcd Carbonlferous

rocks in the Lower and MiddJe Triassic sédiments

at Matenlcozha (Icft bank of Ural River) suggests

thar not only the Permian but aiso the

Carboniferous rocks from upliited surrounding

areas are eroded (Kukhtinov et ai 1982).

The existed water basins are quite shallow. In

rocks, numerous cracks from drying arc found,

stream bedding and organic remains, adapted to

cnvironmcni with lemporary drying-up -

amphibians, osttacods, fishes, concho.straceans.

Oxidising conditions prevailing hcrc. Only in

the middie Olenekian marine basin, with clay

and limestone deposits, the environment changes

to regenerating. More active processes ol Chemi¬

cal érosion lake place. Jtidging to the ostracod

distriburion» multicolouied and red sédiments

are formed not only in conrinenta! environments

but also in the periphery of salty basin.

At the end of rhe Early Triassic. the sca régresses

and continental régime dominâtes.

l'he Middie 'Friassic (Fig. 12) is characterised by

a new incursion of the sea and irs area of distri¬

bution is quite rhe same than prcviously. The

great change between Lower and Middie Triassic

deposits is probably due to ingression along river

channcls. The normal transgressive sequencc —

sandstones, clays, limestones - of the

Akmajskaya seric.s and variegated rerrigenous

deposits of the surrounding ilatlands are dcvelo-

ped. The rcmains of ostracods, molluscs, fishes

and charophnes, not clcarly marine, indicate rhe

hindered connection wich the occân. The

Sravropol uplift of Northern Cauca.sus, of

Middie Caspian, of Karabogaz and Buzachink

domains, the cnierged eruptive massifs of

Mangyshlak as well as organogénie buildings

could be- considered as palaeogeographic barriers.

During the second half of tfie Middie Triassic.

carbonate deposits are occasionak Almost every-

where, grey and rarely variegated sand.s, aleuro-

htes and clays are depo.siied. The area of

distribution is considcrably extended outside uf

the Dépréssion, i.c. into the Southern Pre-Und

and Pre-Ur.dian trough. In the north-cascern part

ol the Dépression, rhe marine environments arc

episodically replaced by transitional zones (Coas¬

tal plains with coal accumulation.s). Numerous

ostracods, including the brachihaline Gemma-

nella genus, are associated wich chese deposits

(Aralsorîan sériés). Single marine euhaline

Hiurdia genus is found with them.

During the Late Triassic, approximaicly rite same

situation is preserved. Under a humid climate,

i herc is great abundance of hygrophytes on insular

and Coastal lands, conifers with fern underbrush

and pteridosperms on high lands. în the rransirio-

nal areas, herbaccous sss^ips and overgn>wn lalces

arc widcly dcvcloped. In the basin, the conditions

are changed time to time into oxidising shallow

water environments. The irregular intcrbcddmg of

sands and clay.s shows rhe euscaric movements.

The central areas of the Dépréssion subside inten-

sivcly with important filling. The increase of terri-

genous matcrial shows the uplift of emerged areas.

The régression continues and the continental

environments dominatc.

At the end of the Triassic-beginning of the

Jurassic, ihe Precaspian Dépréssion, especially its

western part and the adjacent areas, are uplifted

and bccome érosion lands.

Acknowledgements

The authors are very grateful to the reviewers

GEODIVERSITAS • 1999 • 21 (3)

345

Kukhtinov D. A. & Crasquin-Soleau S.

who coiuributed to the iniprovcment of the text:

Prof. (j. B. Vai (Bologne) and Prof F. Feinbcrg

(Paris). We are indebted lo Mrs A. Cambreleng

(Laboratoire de Géologie, MNHN) for the dra-

wing of the profiles and palaeogeographic maps.

REFERENCES

Anonymous 1982. — Conclusion of the Interdepart-

mental meeting on the Triassic of the Eastern

European platform with régional strati^uiphic scheme.

MSK, Leningrad. (A p.

Demehuk !.. V.. Zofkina V. A. et aL 1971. — The

histor)' o( the Prccaspian deptession at Mesozoic

time. F^roceeding of VNIGNI, Nedra, Moscow, 109,

120 P- (in Rusdan).

Dmitriejcvskij A. N. 1906. — Litbology, mineralogy

and origin of lipper Permian and Lower Triassic

deposits on the eastern part of the Preenspian

Dépréssion in regard w tneir oil and gas présente.

Abstract of candidate dissertation. MIKKH and

GP, Vtoscow. 21 p. |in Rus.sunf

Dmitricjcvsldj A. N. \Si. Pro.shijakov B. K. 1970, —

Palaeogeography of rhe eastern part ol the

Precaspian Depres.siun at the Late Permian and

Triassic tîine; 120-127 |iii Riissian|, in Oil and gas

search in sait dôme areas. Ncdta, Moscow.

Janochkina Z. A. & Srarisev V. F. 1977. — Chain-

size ujnrcnr of sand-alcurolirc Tria.ssic rocks of the

Preca.spian Depres.sion as their genesis index.

Prohlems of Geohgy of Southern Usai and Volga

région {Povolzhjeh Publication of Satainv Univer-

sity, 14: ■^2-84 [in Rus-sian]-

Janov E. N. 1956. — On the origin of rhe red and

grey cuiour of depositional rodes. Reports of the

Acadi tny oj Sciences Of IFSSR 3 (6)- 22-24 [in

Russian],

Kozur H, 1973. — Die Bedeutung triassischer

Osrracoden fur stratigraphische und Palaokolo-

gische Untersuchungen. A'Iittellungen der GeselT

schaft der Géologie und Eerghaustudentin in

Osîerrekb. Innsbruckil; 623-660.

Kukhtinov D. A. 1976. — Bwstratigraphy of Triassic

deposits of the Precaspian dépréssion on ostracods.

Ncdra, Moscow, 99 p. (in RussianJ.

— 1984, — The Upper Penninn and Triassic of Aral-

Caspuin areas (ostracods, stratipaphy, palaeogeogra¬

phy). Ab.straci of docior dissertation, VSECiEL

Leningrad, 37 p. [in Russian).

Kukhtinov D. A., Alckscjeva V. 1. & Kalniykova

A. G. 1982. — On the rc-deposition of palaeonto-

logical remains during rhe Permian and ’Lriassic in

the Precag^ian dépréssion and its possible causes.

Reports of Academy of Sciences of USSR 264 (3):

672-674 [in RussianJ.

Miiiikh M. G. & Minikh A. V. 1997. — Ichtyofaunal

corrélation of ihc Triassic deposits from the north-

ern Qs-Caspian and Southern Cis-Ur.il régions, in

Ciasquin-Solcau S. & De Wever P. (eas). Péri-

Teihys: stratigraphie corrélations h Geodtuersitas

19 12): 279-292.

Molosiovskaj^a i. l. 1997. — Stratigraphie corrélation

of rhe Upper Permian deposits from ihc South of

the Cis-Ural marginal 1 rough and the adjacent

arca.s of the Russian Plate, m Gnsquin-Solcau S. Ôc

De Wever P. (eds), Pen-Tethys: stratigraphie corré¬

lations 1, Geodiversitas 19(2) : 247-259.

Movshovich E. V. 1977, — PaUtogeogutphy and

palaeotectonic of the Lower Volga Région (PovobJyje)

during Permian and Triassic. Pnblicarion ofSararov

Umversiiy, Sararov, 241 p (in Russian].

— 1994. — Problcms ofUpper Permian and Triassic

stratigraphy of western parr of Norih-Caspian oil

.^nd gas basin. Nedra Povolzhja i Prtkaspia,

NVNIIGCL Sararov 6: 33-37 [in Russian].

Mov'shovich E. V. ^ Tsebenko l. N. 1974. — On

the prahlcm of pnlaeogeogaphy of Kalmyk-

Asirakhanian Precaspitin Triassic. Prohiem of geoche-

misiry of f'recaspian-. 97-104 (in Russian].

Publication of Kalmyk Universit)', Elisra.

Oche\' V. G. &; Shishkin M. A. (1989). — On ihe

principles of global corrélation on ihe continental

Triassic Tetrapods. Acta F^tlacontologica Polonica,

\Var7awa34 il): 149-173.

Pronicheva M. V. & Savinovâ G. N. (1982). —

Palaeogeonwrphobgicdl analysis of oil and gas bcaring

areas. Nedra, Moscou', 254 p. fin Ru.ssianj.

Shelechova M. N., Miisikhin V. P. ^ Kukhtinov

D. A. (1989). — Relative lo Bcsobinian formation

définition in Lower Jurassic deposits of the

Preca.spian depres.sion. Palaeontological volume,

Lvov 26: 43-49 [in RussianJ.

Shelechova M. N.j Volchegurskij L. F., Volosaev

V. A-, Musikhin V. P., Perevozchikova I. V. Ôc

Jakovlcv L. P. (1988). — Bii>stratigraphy ul Middlc

and Upper Triassic dqnïsits of Eastern Precaspian.

Palaeontological volume, Lvov 25: 84-91 [in

Russian).

Slicvyrcv A. A. 1990. — Armnonotds and cbronostratT

graplfy of the Triassic. 1-179 (in Russian). Nauka,

Moscow.

Shishkin M. A. & Ochev V. G 1992. — On the age

EriosJichus and Mastodonzaurus faiina of verte-

brates of the Eastern Europe. Transactions of the

Academy of Sciences USSR, Gcological sériés,

Moscow 7: 28-35 (in Rus.sian].

Siibmitted for publication on 22 April 1997;

accepted on 30 July 1998.

346

GEODIVERSITAS • 1999 • 21 (3)

New stratigraphie and palaeogeographic data on

Upper Jurassic to Cretaceous deposits from the

eastern periphery of the Russian Platform

(Russia)

Valentina S. VISHNEVSKAYA

Institute of the Lithosphère, Russian Academy of Science, ILSAN,

22 Staromonetny. Moscow. 109180 (Russia)

valentina@ilsan.msk.ru

Patrick DE WEVER

Laboratoire de Géologie, Muséum national d’Histoire naturelle,

43 rue de Buffon, F-75231 Paris cedex 05 (France)

dewever@mnhn.fr

Evgeniy Yu. BARABOSHKIN

Moscow State University, Geological Faculty,

Vorobjovy Gory, 119899 Moscow (Russia)

barabosh @ geol.msu.ru

Nikita A. BOGDANOV

Institute of the Lithosphère, Russian Academy of Science, ILSAN,

22 Staromonetny, Moscow, 109180 (Russia)

bogdanov@ilsan.msk.ru

Nikita Yu. BRAGIN

Geological Institute of Russian Academy of Science.

Pyzhevsky per., 7, Moscow, 109017 (Russia)

bragin@ginran.msk.ru

Lubov G. BRAGINA

Geological Institute of Russian Academy of Science.

Pyzhevsky per., 7, Moscow, 109017 (Russia)

bragin@ginran.msk.ru

Alesia S. KOSTYUCHENKO

Technical University.

Leningradskoe shosse 112-1-1-211, Moscow, 125445 (Russia)

valentina@ilsan.msk.ru

Emmanuelle LAMBERT

Laboratoire de Géologie, Muséum national d’Histoire naturelle,

43 rue de Buffon, 75231 Paris cedex 05 (France)

geolhote@mnhn.fr

GEODIVERSITAS • 1999 • 21 (3)

347

Vishnevskaya V. S., De Wever P., Baraboshkin E. Yu. et al.

Yuriy M, MALINOVSKY

Institute of the Lithosphère, Russian Academy of Science, ILSAN,

22 Staromonetny, Moscow, 109180 (Russia)

barejko@iIsan.msk. ru

Kulyash M. SEDAEVA

Moscow State University, Geological Faculty,

Vorobjovy Gory, Moscow, 119899 (Russia)

koozminov@mtu-net.ru

Galina A. ZUKOVA

Simbirsk Geological Survey,

3a Dovatora, Uljanovsk, 432000 (Russia)

Vishnevskaya V. S.. De Wever P., Baraboshkin E. Yu. eiai 1999. — New stratigraphie and

palaeogeographic data on Upper Jurassic to Cretaceous deposits from the eastern peri-

phery of the Russian Platform (Russia). m Crasquin-Soleau S. & De Wever P. (eds). Peri-

Tethys: stratigraphie corrélations 3, Geodiversitas 21 (3) : 347*363.

KEYWORDS

Jurassic,

Cretaceous,

strarigiaphy,

ammonites,

radiolarians,

foraminifera,

nannofossiU,

palaeogeographical map.

ABSTRACT

The Late Jurassic and Late Cretaceous were periods when, after prolonged

continental érosion, stable marine sedimentarion took eftect on the Russian

Platform. The sédiments which accuniulated hâve diverse lithological com¬

positions iuid a mixture ot rransient and endemic faunas. Lithological diversi-

ty and a widc varierv of faciès lias led to problcms in stratigraphical

corrélation of Late Mc.sozoic séquences and discrepancie.s in palacogeographi-

cal reconstructions. DifFerenr faunal groups belonging to a wide variery of

palaeozoogeographic provinces exist within these deposits. rherefore> wc use

ail available microfossils (radiolarian.s, foraminiferas, nannoplankton) and

macrofossil groups (aimuonites, buchias, inoceraniidcs) in order to cstablish

the synchronicity of anoxie and other events, to propose biostratigraphic

zonations and model the palaeogeography for Late Jurassic: lower

Kimmeridgian and middle Volgian as well as Cretaceous rime. We suggest

that the Peri-Tethys Eastern Europe is a unique area in which to solve the

problem of stratigraphie corrélation as it incorporâtes both Boréal and

Transicional roTcthyan palacoclimatic provinces.

RÉSUMÉ

Nouvelles données stratigraphiques et paléogéographiques sur les dépôts juras¬

siques et crétacés de l'extrémité orientale de la Plate-forme russe (Russie).

Le Jurassique supérieur et le Crétacé forment une période où, après une

longue érosion continentale, une sédimentation marine stable s'installe sur la

plate-forme russe. Les sédiments accumulés ont des lithologics variées et pré¬

sentent un mélange de faunes endémiques ou transitionnelles. La diversité

lithologique et la grande variété de faciès ont rendu complexes les corréla¬

tions stratigraphiques pour ces séries du Mésozoïque tardif et ont même créé

des désaccords dans les reconstitutions paléogéographiques. Différents

groupes fauniques, appartenant à une grande variété de provinces paléobio-

348

GEODIVERSITAS • 1999 • 21 (3)

Upper Jurassic-Cretaceous of eastern Russian Platform

MOTS CLÉS

Jurassique,

Crétacé,

stratigraphie,

ammonites,

radiolaires,

foraminiferes,

tiannofossilcs,

carte paléogéogfaphique.

géographiques existent dans ces depots. De ce fait, nous avons été conduits à

utiliser tous les groupes disponibles de microfossiles (radiolaires, foramini'

feres, nannoplancton) et de macrofossiles (ammonites, buchias, inocéia-

mides) afin d'érablir le synchronisme des événements, anoxiques ou aurres,

pour proposer des zonations biostratigraphiques et des modèles paléogéogra-

phiques pour le jurassique supérieur : Kirnméridgien inférieur et Volgien

moyen ainsi que pour le Crétacé. Nous pensons que la partie péri-téthy-

sicnne de TEuropc orientale est un endroit unique pour résoudre les pro¬

blèmes de corrélation strarigraphique puisqu’il incorpore des éléments fau¬

niques de provinces boréales et de la transition vers le.s provinces

paicoclimatiques téchysiennes.

INTRODUCTION

Our research team bas undertaken field work in

Volga River Basin (August 1995, members of

field work team werc as follow: E. Baraboshkin,

N. Bragin, £. Lambert, V. Visbnevskaya,

G. Zukova; August 1997, V. Vishnevskaya,

G. Zukova) and in the Tiinan-Pechora Basin

(September 1995, A, Kosiyuchenko, G. Sedaeva,

V. Vishnevslcaya).- Ali prcviously publishcd and

unpublishcd data concerning of thcsc régions

were reviscd and taken inco account.

The aim of our field trips was to collect précisé

and well-Iocated samples with fossil material in

order to estabÜsh accuratc biostradgrapbical cor¬

rélations and ro propose palaeogcographic

reconstructions which could provide a basis for

modelling of palaeogcographic map.s.

During die field workv wc investigated and sara-

pled the following areas in detail: (1) Kim-

meridgian-Volgian portion of the standard

Gorodische .Section of Volga River Ba.sin and

Ukhta outerop as well as 21 outciops and

52 boreholcs of the Volga-Kama and Timan-

Pechora Basin (Figs 1-5); (2) middlc Volgian-

Haucerivian sections near Gorodische and New

Berdianka villagc-s (Figs 2, 3); (3) Aptian-AJbian

sections from borehole.s of the Penza région

(10 km of Penza town, west of Volga River);

(4) Barremian-Turonian section to the norch of

Uljanovsk city; (5) Cenomanian-Maastrichtian

sections ncar Shilovka scttlcmcnc (50 km south

of Uljanovsk city).

MAIN LITHOFACIES AND STRATIGRA-

PHY OF THE KIMMERJDGIAN

The lower Kimmcridgian Js represented by orga-

nie shale (Fig. 5, borehole 18) with clay (Fig. 5,

boreholes 15'17, 19. 20, 22. 23, 25-27), glauco-

nitic sandsl'one, aleurolite (almost équivalent ro

silt-stone in Russian litcrature) and clay (Fig. 5,

boreholes 24, 28), and micrite in the outerops ol

the Uldita section. Rare phosphatic pcbblcs and

pyricic concrétions werc also tound.

The time interval investigated corresponds to the

early Kimmeridgiaii in ternis of standard ammo¬

nite zonation for the Boréal Realm of rlie

Russian Plate. Withiii the Bareiits-Pechora area,

the Amoe/pf/ceras raimi zone and in the Volga-

Kama-Oka Basin, the A. kitchmu zone are pré¬

sent. Other characreristic ammonites are Rasenia

trimera Oppel and R. stephunoides Oppel.

Kimmeridgian straca, which yieJded radioIarian.s

(Kozlova 1994; Vislinevskaya 1997), are well

reprcvscnted in the Timan-Pechora Basin. The

Pcchota-Volga sedimentary basin was probably

produccd by a Lare Jurassic phase of rifeing

(Kostiuchenko 1993), and was filled with radio-

larian-bearing clay and shale deposirs m a sub-

platforni environment.

The Kimmeridgian clay of Pechora and Ukhta

region.s is also rich in glauconite and moritmo-

rillonite. Glauconite (15-30%). montmorillonitc

(10-30%), hydromica (10-30%) and chloritc (5-

10%) arc the dominant components in

Kimmeridgian bituminous clay whereas glauco-

GEODIVERSITAS • 1999 • 21 (3)

349

Vishnevskaya V. S., De Wever P., Baraboshkin E. Yu. et al.

50" 54° 58° 62°

Fig. 1. — The location of investigaîed boreholes and outcrops of Timan-Pechora Basin (the numbers correspond to their official

record).

nite (30-40%), kaolinite (25-30%), and mont- the total fauna. Practically ail taxa présent are

morillonite (20-30%) predominate in the known in the Boréal province of the Russian

organic-rich Volgian shale. Platform and Circum-Pacific Rim. The lower

The Kimmcridgian chay (5-45 m) from the Kimmeridgian radiolarian assemblage of the

Pechora and Ukhta régions has a conformable Parvicin^da vera zone ol the Barents-Pcchora-

stratigraphic contact with the underlying strata Ukhta région includes: Archaeocenosphaera

(Fig. 5) and demonstrates a succession of irans- inequtilh (Rust), Praeconocaryommd ex gr. sphae-

gressive and régressive characiers up to Volgian rocofUis (Rust), Pseudocrucelln aff pniva Blome,

strata. Crucella crassa (Kozlova), C :;quama (Koziova),

Radiolarian taxa make up only a minor part of C. aff. mexicana Yang, Orbiculiforrna cf. iniqua

350

GEODIVERSITAS • 1999 • 21 (3)

Upper JurassiC'Cretaceous of eastern Russian Platform

)

^ 0 km 30

. Dubki / J '

Undory .. '

|Gorodisc)ie|

I Novaya •: [

■ r

VShHovkæv

f '\ i

LEGEND

10 cm

r ■

[H]

Breccia

Sands

Sandstones

Siltstones

Clays

Oil shales

Argillites

Maris, clayei maris

Limestones

Carbonate clays

Phosphorites

Bioturbation

Shell detrite

Erosional surfaces

Softgrounds

PiQ 2. — The location of investigated sections of Volga Basin and stratigraphie column of the Volgian stage of the Gorodische

Section.

GEODIVERSITAS • 1999 • 21 (3)

351

Vishnevskaya V. S., De Wever P., Baraboshkin E. Yu. et al.

Blome, O.? renisa (Koziovu), PatUaneilium ünra-

blankaense Pessagno McLcad, Parvicingula

inornata Blomc, P. cl. blinvi Pessagno, P haevkeli

(Pantanclli), P burnensis Pessagno & Whalcn,

P pizhmica Kozlova, P pusilla Kozlova, P papula-

ta Kozlova. P siintabarbarerms Pessagno, P?, enor-

mis Yang, /?? blackhorncmis Pessagno Whalen,

ExcinguliP bifaria Kozlova.

The lowcr Kimmeridgian Paraicingula vera zone

of the Barents-l'iman-Pechora Basin (Vish-

nevskaya & De Wc\'et 1996) is probably équiva¬

lent to the lovver Kimmeridgian Crucella crassa

assemblage of Kozlova (1994) and corrclaces wich

the Buchîit concentrica zone, A. ravni ammonite

zone and Epntvmina unzhemE foratniniferal zone

as well. This interval probably corresponds to the

Kimmeridge Clay H/drocarbon Formation of

the North Sea which Contains abundant P jonesi

(Dyer & Copestake 1989).

A srudy Parvicingula distribution shows a pré¬

dominance ofthis genus in the Kimmeridgian of

the Timan-Pechora and Barents régions. Species

of this genus are represented bv a wide range of

morphotypes. The co-occurrence of Arcco-Boreal

foraminiferal assemblages tugether wiih Juras.sic

radiolarians and Buchias confirms the possibility

of using Panncingnbt as palaeoclimaric indicacor

(Vishnevskaya 1996). For example, the main

Kimmeridgian représentatives of the Moscow

région are Parvicingula vera Pessagno & Whalen,

P inoymata Blome, P elcgayis Pessagno &: Whalcn.

Parvicingulides- prcvail, comprising 50% of this

assemblage and in the middlc Volgian of the

Moscow Bàsin, arc represented by P haeckeli

(Pancanelli), P hexagonaux (Heitzer) (Bragin

1997).

In the Gorodische Section (Volga Basin)

Parvichigula jonesi (Pessagno) is the dominant

species în the Kimmeridgian and the percentage

of parvicingulides in the total radiolarian fauna

reaches 50-60%.

Radiolariaii-bearing organic black shale and bitu-

minous clay which were deposired in anoxie

environments are assigned to the lower

Kimmeridgian [Cyrnodoce zone). This interval

exhibits black shale layers with a high TOC

(more 10%) content and good perroleuni poten-

tial (Baudin et al. 1996). Ammonite horizons

containing P densicostata and P baylei can be

Zones GORODISCHE

inversas

>

cr

LU

1—

O

c

X

[L

ce

O

3:

O

_l

£î^

-i ~—Z

4-1

20

syzranicus

S

‘ - •. * F •

6-

0.5

nodiger

CO

Z

<■

a

O

>

cb

<.

cc

a.

Z)

5

subditus

* e O*

8-7

0-0.2

fulgens

' « ' a

0.5-

0.8

nikitini

\ V ■ ■« ' V ‘

. ' to . d ’ •

7/

0.3-

0.5

virgatus

• c * .c ' V.'*

ù ■ i?. i? *

20-

22

0.8-

1

panderi

jpav/ow 2 arays/cens.

OJ

Z

<

O

r —I *

n/Ès -

— t?)

58-

23

6-

9

r O

>

P— _

- 0 Z_^_Q _ ^

c 9

61-

59

0.5-

2.5

pseuofo-

scvthica

sokolovi

klimovi

Z

<

3

O

>

-

-•4 ^ — 'î P —

73-

62

3.5-

6

eudoxus

CvJ

s

Z—Z-^Z^

80-

72

12-

18

cymodoce

l'.'. ; -1 Sand | \

(3^ Clay r@~l

I i ' li Limestone | ^ g]

Oil shale f ^ I

^ \ Phosphaticpebbles

Radiolaria

Nannoplankton

Ammonites

Buchia

Fig. 3. — Composite column of the Kimmeridgian-Hauterivian

stages of the Gorodische Section.

recognised in the lowermost part of Kim¬

meridgian ol the Gorodische Standard Section

{Baylei zone of the Standard Scale).

352

GEODIVÉRSITAS • 1999 • 21 (3)

Upper Jurassic-Cretaceous of eastern Russian Platform

Samples Total amount of samples

Species diversity

Y 95/11-10-4

Y 95/11-10-2

Y 95/11-22

OS Y 95/11-24, 10-

Y 95/11 -25-

OS Y 95/11-2

Y 95/11-31

OS Y 95/11-3;

OS Y 95/11-4

Y 95/11-41

Y 95/11-43-

SIZE-FREQUENCY DISTRIBUTION

OFLoripes fischerianus

(sample Y 95/10-2)

SIZE-FREQUENCY DISTRIBUTION

OF Loripes fischerianus

(sample Y 95/11-26)

SIZE-FREQUENCY DISTRIBUTION

OF Scurria maeotis

(sample Y 95/11-36)

SIZE-FREQUENCY DISTRIBUTION

OF Dorsoplanites sp.

(sample Y 95/11-26)

Fig. 4. — The distribution of sampling and percentages of macrofauna in the Gorodische Section.

GEODIVERSITAS • 1999 • 21 (3)

353

Vishnevskaya V. S., De Wever P., Baraboshkin E. Yu. et al.

The upper Kimmeridgian (Eitdoxus-Auris'

siodoremis ammonire zones) sequences o( the

Gorodischc Section arc represented hy clay mari

with abondant nannofossils. Ter^esîielh jnargerelU

Watznanaia communù and W hritamilca are the

dominant species. The characteristic species are

Slephanolithian bigoti^ DisCurhabdus tuhus^

Podorhabdus cylindratusy P. demssutiis, P. cuvHlieri^

as well as the smallest individuals oi Nunnoconus

steinmânnl (= N. adomï). This nanaoplankton

assemblage is similar to the NW European

Vekshindla stradneri assemblage ot Bernard & Hay

(1974). A more précisé Kimmeridgian radiolarian

zonation may be developed in the near future.

The North Caucasus Kimmertdgian-Tithonian

assemblages include only rare P dhimenaensis

(Baumgartner) and Berriassian assemblages in¬

clude P. boesii (l^arona) (V^Lshnevskaya et al. 1990).

The content of parvierngulides is less than 3% of

the total assemblage in the Tethyan Realm.

VOLGIAN BTOSTRATIGRAPHY OF THE

PECHORA BASIN AND GORODISCHE

STANDARD SECTION

Volgian strata hâve a transgressive character in

the Pechora région (Fig. 5). Among radiolarians

which occiir within the middlc Volgian

Dorsoplariite!: panderl ammonite zone,

Parvicirigtiln papulaia Kozlova, P. conica

(Khabakov), P. crinatn Kozlova. P. rtigosa

Ko/lova, P simplicim Kozlova arc the dominant

species. Parvicingulidcs again comprise up to

90% of launas in the Barents-Pechora région.

Ammonites, bnchias and foramitiilera are also

abundant in these strata.

The Gorodische Standard Section is the section

which has been iTUjsr completely processcd for

macro- and microlauna (Figs- 2-4).

Studies of the macrofaimal assemblage from rhe

Gorodische Section show (cf. Mivta 1993), ihat

strata in the section can be confidenriy assigned

to two ammonite snbzone.s of the (niiddle

Volgian) Dorsoplaniti^a panderi zone: î he

Pavlovia piwhvi boitom subzone and ZMraiskiies

zarajskensis top subzone, which were established

by Gera^imov & Michailov (1966).

The pavlovi subzone (layers 61-59) is characteri-

sed by clayey-carbonate succession wirh thin

phosphonte and marcasite horizons (Fig. 3).

Several erosional surfaces arc rccognised in the

subzone. Other anirnonites include Ztiraiskites

sp., Z, cf. tschernyschovfy Z. cf rnichalskii,

Dorsoplanitei aff pamierb D, sp., Pavlovia sp-,

numerous rostrums of LagonibeUis {L) parvula

togciher with a bcnthic Kuinal assemblage of the

bivalves Loripes fischeriaaus^ Buchia rüsslensis,

Oxytoma sp.> Protocardia cont'ijîfut. Gresslya

aldtiiniy gastropods Eueyclm sp., Apporbais sp.,

brachîopods Lingula sp-, Rusiella sp.,

Rhynchnnella loxie\ .scaphopods Laevidentalium,

as well as serpnlids. Fhcsc a.sscmblagcs permit us

to characterise sedimentary conditions as wcakly

anoxie shallow water

A somevvhar rieber fossil coniplex is présent in

the z-tzrajskensis ^nhzow (layers 58-23). The rocks

of this 5ubzor»e hâve rhythmical structure.

Rh)Thms u-sually begin with horizons of rework-

ed .^nd dissolvctl fauna. l'hey arc ovcrlain by car¬

bonate days coppcd with oil siialc. The quantity

of organic matter increases from 1-1.5 ’Mj up to

almost 22% ar the background ot decreasc of

carbonate matter (Fig. 3). Rhythmic changea in

the benthic assemblage occur from a prevalence

of benrhüs to an upseciion increase of nekton

(Fig. 4). In rhe oil shales young populations of

lost Loripn pscheTuinus and Scurria maeoth usual-

ly prevail, together with nepioiiic ammonites.

This demonstrares a strong anoxie impulse

during the oil shale lormaiion. The tollosving

faunal assemblage was dciermincd from that

interval: ammonites Zitrahkiies cf. scyibicus^

Z. pillcensis, Z. quenUedùi. Z. stchukivensis,

Dorsoplanifespanderh belemnires lagimhetm {L.)

magiiifica^ {Rolcobeloides) vplgemis^ L {L ) cf.

rosanovp bivalves Astane sp., Gresslya alduini,

Buchia mosqueusisy B. russirasis, Oxytoma sp.,

Loripes fjscherianusy Nucula sp.v Panopea .sp.,

Limaxula consobrintu Liostrea plaslicax giisrropods

Scurria maeotisy Eucychts sp.; scaphopods

Laevidenuilium sp.; hrachiopods Lingula sp.,

Rhynchonclla rotiillkri and oihcr tauna.

'l'he radiolarians Orbiculiforma ex gr. mclanghli-

ni Pcs.sagno, StichocapSiP devorata (Rust),

Pbormocampe favosa Khudyaev, Parvicingula

hexagonata (Heitzer), P. crïstata Kozlova, 7? conica

(Khabakov), P aff. alata Kozlova, P. nndtipora

354

GEODIVERSITAS • 1999 • 21 (3)

Ig g Ammonites

Radiolarîans

Belemnites

Anceline

Bioturbations

Fig. 5. — The distribution of Jurassic faciès within the sections of the north-eastern part of the Russian Platform. For the location of boreholes see in Fig. 1. For legend of columns 1 -

14 see Vishnevskaya (1998), 29-52 see Vishnevskaya & Sedaeva (1999). P, Permian; T, Triassic; J, Jurassic; K, Cretaceous; Q, Tertiary; a, Aptian; al, Albian; h-b, Hauterivian-

Barremian; bs-v, Berriassian-Valanginian; ne, Neocomian; v, Volgian; ox-km, Oxfordian-Kimmeridgian; cl. Callovian.

U)

\j\

Upper Jurassic'Cretaceous of eastern Russian Platform

Vishnevskaya V. S., De Wever P., Baraboshkin E. Yu. étal.

(Khudyaev), P. uff. haecktii (PantancJli), P. aU'.

spinosa (Grill & Kozur). PLithycryphalus} pumilus

Rust, Lithocampe cf. ternkeriata Riist werc reco-

vercd fiom within the Donoplanites panderi

ammonite zone in rhe Z. înmpbenuî siib/nne —

the Lippcrmost part ol^ nannolossÜ Wntznaueria

communis zone ot rhe Gorodisclic Section, where

dominant specics ot coccoÜths are W. murtelae,

W. sîrigosâ, W tubulatû, W. oiutta.

Higher in the section (layers 22-20) thin mem-

bers of quariz-glauconiric sands and sandstones

build up the succession. They contain horizons

with rewofked phosphoriics. b'aüna.s are located

predominanrly in rewa.shed pebbics. In layer 20,

remains ot stroogly reworked zonal index

Virgatites gtTasnvtovi were fourid tugether with

Loripes sp. and dissolved rostrums of Lagonihelus

{H.) volgensn. There are many radiolarians

reworked from the Z. Zitrajskmsis su\y7.onc within

the phosphoriie pebbles.

Ammonites Irom the succeeding Virgathes uirga-

tus next zone were not discovered. However, on

the basis of stratigraphie position in a detailcd

section, this zone most likely occurs between

layers 18 and 20.

The uppermosT part of section is comprises

dense thin memhers ol carbonate sandstones

with huge ammonites Epïvirgaîites btplkiformh

and E, nikitini (layers 17-12) from the middlc

Volgian £ nikitini zone

Sandstones of rhe upper Volgian Knchpurites fid'

gens zone lie above an erosional surface. They

contain Craspeditcs nekrassovh C sp. and Kach-

purites fulgens associated with Buchia piochiis

B. sp., bclemnites Acroteuthis (A.) mssiensis and

A, {A.) rnosquensis^ which were found in layers 11

and 10.

Overlapping layers 7, 8 also lie above erosional

surfaces érosion and arc characteriscd by rework¬

ed Craspedites cf okensis. which i.s the diagnostic

form of the upper V^olgian Craspedites siibditus

zone. The bclemnites Acroteuthis (A.) mosquensis

and bivalve Buchiapiochii and B, tenuicollis occur

together with chese ammonites. Radiolarian .spe¬

cics P. crisiata Kozlova, P alata Kozlova, P. blnwi

(Pessagno) and Sticbocapsa dcvorctia (Rust) are

common within thèse strata in which the parvi-

cingulid content is 50-60%.

No ammonite fauna was found in layers 6-5 , but

based on extsting Ütcraturc (Mcsczhnikov 1984),

thèse strata can be correlated with the upper

Volgian Craspedites nodiger zone and lower

Valanginian Temnoptychites syzranicus zone I he

iLppcrmo.st part ol Volgian stage i.s char.tcterised

by appearancc, within the radiolarian microf.iuna,

of the Mediierrancan spccies P hoeni (Parona).

l'hc appearancc of this Mcditerranean species

taxon notwithstanding, radiolarian assemblages

are dominantly Borcal in character and ihc tj'pes

of radiolarian assemblages presem bave not been

described previousJy. The proposcd middie

Volgian Parvidngnla haeckeli zone is closelv cor¬

related ro the ParvicinguLt papulata zone of the

Pechora Région (Kozlova 1994). le cortclates

with the ammonite Dorsoplanires panderi zone

which can, tn turn, be correlated with the

Euolurinella ernetjnnzevP TraciMnvninn sepientrio-

nuits or Sarûcenclria praimLlvlevi foraminilcral

zone (Kozlova 1994) in the Pechora Basin,

Lemiculma biexcauata zone (l.jurov 1995) in the

cSysola hydrocarbon Basin, and Parhabdolithus

embergeri nannoplankton zone in Middlc Volga

hydrocarbon Basin. Wc can trace lasi zone

through both Southern England and North

France (Vishnevskaya De Wever 1996). Due

to the présence of index .species> it is possible to

corrclatc rhis interval with buchias Buchia mos-

quensis-B. mssiensis zone ol the Russian Platlorm

(Sey & Kalacheva 1993).

The proposcd upper Volgian ParvicinguLi blowi

zone probabi) corresponds co rhe Psevdo-

crolanium pinnocephala assemblage of rhe

Pechora and North Siberia régions which was

established by Kozlova (1994) and can be corre-

laced with Buchia piochii-B. tervbratuhndes zone

ol the Russian Plaiform (Sey ÔZ Kalacheva 1993).

JURASSIC PALAEOGEOGRAPHY

The Jurassic stratigraphie sequences in the

4 irnan-Pechora Basin (Fig. 5) clearly show a

transgressive dcposliional System scarting with

Early-Middie lurassic sands and deepening

Lipward to ilie accumulation of ilie higher grade

source rocks in rbe Volgian lime. The mass

extinction, observed herc and espccially in the

Gorodische Section ol the Volga-Urals Basin

356

GEODIVERSITAS • 1999 • 21 (3)

Upper Jurassic-Crefaceous ofeastern Russian Platform

Fig. 6. — Schematic palaeofacies location map of the Kimmeridgian time (adopted after Sedaeva & Vishnevskaya 1995). 1, Coastal

marine sandstone and siltstone; 2, marine clay; 3, anoxie organic shale; 4, lignite coal and organic détritus; 5, phosphate; 6, sup-

posed land; 7, location of sections from Fig. 5 (number in circle); 8, location of the Gorodische outerops (letter in clrcle).

GEODIVERSITAS • 1999 • 21 (3)

Vishnevskaya V. S., De Wever P., Baraboshkin E. Yu. et al.

(only about 40 species of ammonites» 20 species

of aucellids, 22 species of bcnihic foraminifcras

and 20 species of planktonic foraminifcras,

10 species of bclemnites, 5-40 calcareous nanno-

fossil taxa, 20 species of radiolarians and sevcral

species of algae were recognised wichin Dorso-

planitespanderi ionç)y probably rcsulted from tlie

cumulative cffects of a constani alternation of

transgressive and régressive épisodes. Tins type of

sédimentation and palaeoenvironments survivcd

into late Vbigian lime, but a change of condi¬

tions had alrcady appeared by thc end of Volgîan

time.

l'he proposed schematic pakeogeographic maps

of rhe Kimmeridgian and Vbigian lime (Figs 7»

8) indicate the location of the eastern rim of

shallovv sea witli excellent environments for oil

and fuel-ricli organic source rocks (Figs 5, 6).

Similar to Recent seas and to an ancient sca, for

cxamplc, thc Devonian Sca (Vishnevska)^ 1093).

thc maximum concentrations of phytoplankton.

siliceoLis plankton and benthos, carbonaceous

plankton, nekton and bemhos were found in ihe

water imincdiatcly boidcring thc continent, l'his

type of relative incrcasc in the proportion of lipid

rich organic matter in thc botvom scdimcnis and

its good pre.servation probably took place in res-

ponse to the preservative characccr of phospho-

rus, the coiueiu of which is very high in these

strata (Bauditi trt al. 1996).

It is well-known that in the Techyan Rcalm the

genus Parvîchigula is rare whcrcas thc content of

this genus in thc Boréal (Khydjaev 1931; Sedaeva

& Vishnevskaya 1995) and Ausiralian provinces

(Baumgartner 1993) is much greater. From these

data, \ve can assume thar cold water environ-

ments dominated lhe north-easiern Rti.s.sian

Plarform Jurassic oil-shale-bearing basin. ’Fhe

prépondérance of parvicingiilides possibly indi*

cates upwelling conditions which bave could

existed offshore (Figs 6-8). The abundant

remains of sponge spiculés, which settled along

rhe shelfedge confirm this conclusion.

JURASSIC BIOSTRATIGRAPHY AND

PALAEOGEOGRAPHY

Detailed analysis of taxonomie variety of faunal

assemblages and some morphological peculiari-

ties of shclls allow us to escablish bioscratigraphic

corrélations and to reconsrnici the possible

bathymétrie and topographie fcaiures of sedi-

menrary basins. One would notice that Jurassic

radiolarian fauna was firstly found from rhe

Corodische Standard Section of the Volga Basin.

It represents new data on the palaeonrological

characceristic.s of the Upper Jurassic Russian

Régional Vbigian Stage. Fhc lower Kimmcrid-

gian ammonite Amoeboceras kitchini (Salfcld) is

cypical of the Arcdc (Northern Siberia, Subpolar

Urals) and Boreal-Atlanîic Provinces (European

Ru.ssia). Buchia is a charactcristic clément of

Arctic and Boréal reairns. Eoraminiteras arc also

cypical of the Borcal-yVtlantic Province. A ly'pical

feaiurc til radiolarian assemblages (abundance

and high taxonomie diversity ol thc genus

Parvicingîda) indicates Borcal affinity. The pré¬

sence of thc genus AsphiocertU In the Volga-Oka

Basin, well-known in the Western Europe and

Mediterranean Région, is the only indicator of

possible letbyan influence.

Sonic pccuUarities were conimon for sédiments

of thc Pechora and Volga baslns:

1. Scdinicntary lithologies and cheir thicknesses

indicate uneven subsidence on thc periphery of

Russian Platfbrm.

2. Alternation of deep-water and shallow-water

sédiments and numerous gaps indicate custatic

variations.

3. Geochemical data exhibit enrichment in orga¬

nic matter.

New siliceous microfossil radiolarian assemblages

hâve bcen obtaîned from the Volgian as dated by

ammonites and calcareous narinofossils.

The co-occurrcncc ol radiolari.ins wilh calca-

reous narinofossils represenrs the firsc well-dated

radiolarian assemblage ol this âge at such a high

latitude on the Russian Platlorm.

As might be expecred many new radiolarian spe¬

cies of the Boréal Province are encouniercd.

LOWER CRETACEOUS STRATIGRAPHY

OF ULJANOVSK-PENZA REGION

Berriasian strata are probably reworked in the

Gorodische Section, although they were niarked

358

GEODtVERSITAS • 1999 • 21 (3)

Fig. 7. — A detail palaeogeographic map of the Volgian time. 1. mari; 2, sand; 3, clay; 4, limestone; 5, oil shale; 6, land; 7, sponge;

8, aucelfine; 9, ammonite; 10. foraminifera; 11, radiolaria; 12, bivalve; 13, glauconite; 14, phosphate; 15, buchia; 16, gypsum.

GEODtVERSITAS • 1999 • 21 (3)

359

Vishnevskaya V. S., De Wever P., Baraboshkin E. Yu. et al.

(?mapped) açcording to Mese/hnikov (1984).

From oiir point of view, fhe pn^sence of Berria-

sian deposits here is improbable because the sec¬

tion is srrongly condensed. Most probably, Bcr-

riasian ammonites which are présent in these

strata wcrc rcworkcd inco thc base ot \ alanginian.

'Fhe section is terminated by black clays

(layers 4-1) witb sidcrite and Jimonite concré¬

tions, containing large weathered ammonites

Speetonicems (5.) .versicolor and S. (S,) suhinver-

surriy which arc ascribcd to tbc Speetoniceras

inversum zone ol thc top Hautcrivian.

An anoxie event occurted within the lower

Aptian Deshayeütes deibayeü The remainder

of the lower and middle Aptian is characterised

by anaérobie conditions. A late Albian radiola-

rian assemblage was Ibiind amongsr the Albian

black clay of Ulianovsk Sec tion. It is rcpre.scnied

by Orbiculifarma multanguLi Pessagno, Théo-

campe cylindrica Smirnova Alicw Oheliscoites

iiirris (Squinabol).

The Barremian-.'Vlbian jnter\'a!s wcrc also investi-

gated in rwo (7, 10) borcholes in the Penza area.

At a depih ot 89 m in borehole 10, the radiola-

rians Orbiculiforma nuixima lV.ssaguo> Disrylo-

capsa micropora (Squinabolj> simdar to laie

Albian Tethyan forms (O' Dogherty 1995);

Dictyomhni communis (Squinabol) and Obesa-

capsula sp. cf O. zamoramsk Pessagno were reco-

vered, At a depth of 105.5 m in the sarne

boreholcv rypical late Albian radiolarian spccics

Porodisens kavUJeuiensis Aliev, Archaeodictyomitra

simplex Pessagno, Dictyomiîra gracilis (Squi¬

nabol), Dictynmitra feroiia àngusia Smirnova,

Theocampe cylindrica Smirnova Ôi Aliev were

recognised. Ar a depth of 106.8 m within bore¬

hole 10, the radiolarian fauna is characterised by

Spumellaria only.

Within borehole 7, ai a depth ol 113.3 m, radio-

larians Orbiculiforma nevadaensis Pessagno,

Oheliscoites perspicutts Squinabol, O. cf. vinassai

(Squinabol), Xiîus antelopensis Pessagno,

X? asymbatos Forcman, ^v^lich arc characteristic

species of thc Albian to carly Cenomanian, were

found. At a depth of 120 m (boretiole 7) radiola-

rians are represented by the species Orbiculi¬

forma nevadaensis Pessagno and typical late

Albian Theocampe cylindrica Smirnova & Aliev,

T simplex Smirnova & Aliev.

I 360

Between 123-45 and 123.50 m, the radiolarians

Porodiscui inflatus Smirnova &: Aliev, Oheliscoites

lurris (Squinabol) arc présent.

.At a depth of 133.15 co 133.25 m the radiola-

tians Dictyomiîra ferosia angusta Smirnova and

Stichomitra communis vSquinabol were recovered.

Within the interval 129.75 lo 129.90 m, Albian

spedes Crolanium cuneatum (Smirnova & Aliev),

C tritjuetrum Pessagno, Porodiscus inflatus

Smirnova ik .AJiev were inet.

At a depth of 136 m. the only .specîes recovered

was Orbiculiforma multangula Pe.ssagno occurred.

From the above data we consider that the

Aptian-Albian Crolanium cunattutn zone can be

recognised in rhe Uljuuovsk-Pcnza Région.

UPPER CRETACEOUS BIOSTRATIGRAPHY

OF VOLGA BASIN

Upper Cretaceous radiolarians were .studied Irom

rhe Shilüvka Section in the Uljanovsk Région

and from cure sections of borcholes (28, 502)

From the Volgograd Région. Three radiolarian

assemblages w^re determined: Archaeospongo-

prunnm hipartiturn-Alieviu m su per bu m

(Tumnian-Coniacian), Pseiidnanlophacus floresen-

sis-Euchitonia santon ica (lace Goniacian-

Santonian or Santonian) and Arnphipyndax

tylotm-Patellubi plunoconvexa (late Campanian).

Age data were supported by loraminiferal and

nannoplankron assemblages, which bave aftînity

with Europeari unes. These as.semblages arc simi-

iar to Western Siberian Boréal associaiion.s. but

include .somc Tethyan Taxa.

Tlic early Santonian Euchitonia santonica-

Alievium praegallotViiyi zone was established by

Vishnevsloiya (1997). It is a cbaracterisrit Boréal

zone and is widespread both in Siberian, Russian

platforms and in the Prc-Caucasus. Within the

Shilovka Section, it corresponds to the foramini-

lcral Gavelinella infrasantonica zone or nanno¬

plankron Marthasîerites (urcatus zone, l hc tare

Santonian-early Campanian foraminiferal

(hwclinclla stelligera zone can be correUted with

the Oiincutifbrma quadraia-Lïthostrobus rostovze-

vi zone. Phe upper part of this zone may be cali-

brated with the nannoplankron Arkhangelskiella

specillata zone in the Shilovka and Tushna sec-

GEODIVERSITAS * 1999 • £1 (3)

Vishnevskaya V. S., De Wever P., Baraboshkin E. Yu. et al.

tions. Campanian Prunohmchium articulati^m

zone (Lipman 1952) or Arnphibrachtum sibert-

cum zone and Spongoprunum angustum zones

(Amon & De Wever 1994) hâve no analogues in

the Terhyan Région. Nevertheless, the Tethyan

species Afens liriodes Riedcl & Sanfilippo was

found in the inrcrval of this zone within the

Shilovka Section.

CONCLUSION

The proposcd biostratigraphic subdivisions based

on new palacontological data are clcarly defi-

nable. They hâve a proven widc géographie dis¬

tribution and can bc usefuJ for corrélation of

sedimentary séquences as well as biotic and abio-

tic events.

The direct corrélation of Peri-Tethyan radiolarian

zonations with oceanic oncs and tliose of lhe

Tethyan région is very difficuli owing to provin-

ciality of species. Only one Jurassic zone, the

Lipper Volgian-lower Berriasian Parvicingula

blowi zone, can probably be compared with

zonations of Baumgartner (1993) for the Argo

Basin. The upper Berrlasian-lower Valanginian

Parvicingula khabakovi-Williriedellnm saltimicnm

zone (Vishnevskaya 1996), which is widespread

in the Rassian and Siberian platlorms within the

ammonite Bojttrkid mesczhnikovi zone^ can be

compare with some Tethyan ones owing to the

presence of numerous Parvicingula hoesii.

Biostratigraphic cofrelaiions oi microfossils

(radiolarians, forauiinifoas and nannoplankron)

and macrofbssils (ammonites, buchias) is propo-

sed in order to cstablish the synchronicity of

events and conscqucntly of more general geologi-

cal processes.

Acknowledgements

We express our gratitude to Professer

A. Nikishin and anonymous reviewers for their

stimulating cornmenis and criücism on the

paper. We arc gracefui to J. Aitchison who hclped

us to improve the English. Spécial thanlcs are due

to Peri-Tcthys Programme (grants 9518 and 95-

96/18) and Russian Foundation for Basic

Research for Financial support (Grant RFFl 97-

05-65566) and to CNRS-ESA 7073.

RFTERF.NCES

Amon E. 6i De Wever P. 1994. — Upper Cretaceous

biostratigraphy of the borders of the Ural belts:

Western Siberian and Eastern Volga-Ural Basins:

229-i62, in Roure F. (ed,), Peri-Tethyan Pbitforvis.

l'echnip ed., Paris.

Baudin F., HariTzperguc P.. Vlitta V., Olfcriev A. &

Zakharov V. 1996. — Biostratigraphic corrélations

and black shaie deposits of the Upper Jurassic from

the Rassian PJatform. Alniracts oj Peri- Tethys

Conférence. Amsterdanu 7. 8.

Bauingartner P. O. 1993. — Lower Cretaceous radio¬

larian biostratigraphy and biogeograpliy *)! nurth-

wesieni Anstralian (OOP -sites 765 and "*66 and

DSDP site 261), Argo Abys-sal Plain and lower

Exni45iiih Plateau. Proceedings oj îhe ÜDP, Scimtific

Resttlh, Washington 123: Z99-342.

Bernard I . & IJay W. 1974. — On Jurassic cocco-

lirhs; lenunve zonation of the Juiassit of Somhern

F-ngland and Korrh France. Edogae gtolo^cea hdve-

ticae, Basel 67 (3): 563-585.

Bragin N, Y. 1997. — Radiobria htmi rhe phospho-

rites basal horizons of the V'oigian Stage in the

Mûscow région. Revue de Mirrùfnilcintfologre. Paris

40 (4) : 285-296.

Dyer R. 66 Cope.srakc P. 1989. — A review of latest

jurassic to earlicst Cretaceous Radiolaria and their

bio.stratigr.iphic potcntial to petrolcum exploration

in the North Sca. Northwest European Micro-

pakontology andPolynohp. London: 214-235.

CsetasimoY P. A. N. Mikhoifov N P. I9c»6. — Volgian

Stage and the gcostratigraphical scalc for rhe Upper

Scriç-s of rhe Jcii ussic System. Proceeding ofAcadetny

of Sciences USSR, ser. geol., Moscow, No. 2: 118-

138 fin Russian].

KhudyaevJ. 1931. — C^n the Radiolaria in phos-

pb ares io the région of rhe Syssola River.

Tramai'tiofH oJ the Geoingical and Pro^pecting Settnee

ifU.S S.R.y Moscow. Fasçicle 46: 1-48.

Kostiucheiikti S. L. 1993, — The continental plate

tectonic mode! of the Timan-Pechora province

based on imegrâred deep geophysical study.

Zonenshtisn niemorial Conférence on Plate Tectonicsy

tiEOMAR, Kiel: 85, 86. '

Koziosa G. E. 1994. — Mesozoic radiolarian assem¬

blage of the Timan-Pcchora otl ficld. Proceeding of

Sankt-Petershurg International Conférence, St-

Perersburg: 60-75.

Lipman R. X. 1952. — Materials on monographie

srtidy of Upper Crctaceoirs radiolarian.s from

Russian pLirlorm. Paleontology and Stratigraphy,

GosgeoJisdai, Moscow; 24-51 [in Russian].

L.jurov .S. B. 1994. — Divi.sion of Jura.ssic .séquences

of rhe Middle Vichegda. Abstracts of International

Symposium *7imtnitigraphy ofoil f!elds'\ December

1994, St'Pc'tcrsburg: 59, (lO.

Mesezhnikov M. S. 1984. — Excursion 060.

Boundary beds of Jurassic and Cretaceous in the

362

GEODIVERSITAS • 1999 • 21 (3)

Upper Jurassic-Cretaceous of eascern Russian Platform

MiddJe Povolzhie and Riazanian région: 38-49, in

The Central régions of European part of the

RSFSR. The summary gnidebook of excursions 059,

060, 066 XXVII International Geolo^cal Congress.

Nauka, Moscow.

Mitta V. V. 1993. — Ammonites and zonal sti'atigra-

phy of the Middle Volgian of Central Russia.

Naukova Dunika, Kiev, 132 p. [in Russian].

O’Dogherry L 1995. — Biochronologv' and paleon-

tology of Mid-Cretaceous radiolarians from

Northern Apennincs (Italy) and Bctic Cordillera

(Spain). Mémoires de Géologie^ Lausanne, n” 21,

415 p.

Sedaeva G. M. & Vishnevskaya V. S. 1995. —

jurassic paleoenvironments of the North-Eastern

European platform. Zonenshain Conférence on Plate

Tectonics, GEOMAR, Kiel: 205.

Sey I. I. & Kalacheva E. D. 1993. — Buchiids and

zonal stratigraphy of the Upper Jurassic deposits of

the northern Far East of Russia. Geologia and

Geofizica, Novosibirsk, 34 (8)> 12 p. [in Russian].

Vishnevskaya V. S. 1993. — Model ol sedinientar)^

basin for the Domanik-rype deposits: new version.

Zonenshain memorial Conférence on Plate Tectonics,

GEOMAR, Kiel: I5M52.

— 1996. — Parvicingula as indicator of Jurassic to

Early Cretaceous paleogeographical and sedimento-

logical paleoenvironments within North Peri-

Tethys. Abstracts of Moscow PerTTethys Workshopy

Moscow: 30, 31.

— 1998. — The domanikoid faciès of the Russian

platform and basin paleogeography, in Crasquin-

Soleau S. & Barrier E. (edsh Peri-Tethys memoir 3:

Stratigraphy and évolution of Peri-Tethyan

Plarforms, Mémoires du Muséum national d'Histoire

naturelle, Pari.s, 177 : 45-69.

Vishnevskaya V. S., Agarkov Yu. V., Zakariadze G. S.

& Sedaeva K. M. 1990. — Late Jurassic-

Cretaceous radiolarians of the Gréai Caucasus as

key to détermine age and paleoenvironment of the

Lesser Caucasus ophiolites. Reports of Russian

Academy of Science, Moscow 310 (6): I4l7-l421.

Vishnevskaya V. S. & De Wever P. 1996. — About

possibility to corrclate North Peri-Terhyan radiola-

rian events with others zonations. Abstracts of

Moscow Peri-Tethys Workshop, Moscow: 31, 32.

Vishnevskaya V. S. & Sedaeva K. M. 1999. -—

Reconstructions of sedimenrary paleoenvironments

of the north-eastern European platlorm and adjoi-

ning areas for some intervals ol Jurassic: 94-98, in

Geology and minerai resources of European North-

Eastern Russia: New results and new perspectives,

Proceeding ofXIIl Geological Congress of Komi

Respublica. Volume 2. Geological Institute of

Uralian Branch of Russian Academy of Sciences,

Siktivkar.

Submittedfor publication on 22 April 1997;

acceptedon 30June 1998.

GEODIVERSITAS • 1999 • 21 (3)

363

Some features of the Early Cretaceous sédimen¬

tation in the Cis-Caucasia reflected in magnetic

properties of the sedimentary cover

Andrew Y. GUZHIKOV & Edward A. MOLOSTOVSKY

Institute of Geology, Saratov State University,

Moskovskaya Street, 161, Saratov 410750 (Russia)

guzhikovay@info.sgu.ru

Guzhikov A. Y. & Molostovsky E. A. 1999. — Some features of the Early Cretaceous sédi¬

mentation in the Cis-Caucasia reflected in magnetic properties of the sedimentary cover, in

Crasquin-Soleau S. & De Wever P. (eds), Peri-Tethys: stratigraphie corrélations 3,

Geodiversitas 2^ (3) : 365-385.

KEYWORDS

Petromagnetism,

scalar magnetic characteristics,

magnetic suscepribility,

Para-Tcchys,

Early Cretaceous.

ABSTRACT

This paper présent the resulcs from pctromagnetic studies of the Noi th

Caucasus-Lower Cretaceous deposirs. Analyses of rhe magnetic properties of

rocks in base sect.ion.s hâve allowed to rcveal scvcral impulses of tectonic acti¬

vation in the Hauterivian and Barremian. The impulses were accompanied

by transport of magnetic terrigenous material from the magnetic complexes

of the Centrai Ridge into the Cis-Caucasian Basin.

MOTS CLÉS

Péiromagnétisme>

caractéristiques magnétiques,

susceptibilité magnétique,

Para-Tétnys,

Crétacé inférieur.

RÉSUMÉ

Quelques caractéristiques de la sédimentation du Crétacé inférieur en Cis-

Caucasie a travers les propriétés pétromagnétiques de la couverture sédimentaire.

Cet article présente les résultats d’une étude pétromagnétique sur les dépôts

du Crétacé inférieur du Nord Caucase. Les analyses des propriétés magné¬

tiques des roches ont montré plusieurs poussées de Tactivité tectonique

durant THauterivien et le Barrëmien. Ces impulsions se sont accompagnées

d’un transport du matériel terrigène depuis les complexes magnétiques de la

ride centrale jusque dans le bassin Cis-Ouralien.

QEODIVERSITAS • 1999 • 21 (3)

365

Guzhikov A. Y. & Molostovsky E. A.

INTRODUCTION

The resulrs of pecromagnetic research on the

Lower Cretaceous deposics from the central and

eascern parts of the North Caucasus are presen-

ted with rhe géologie interpreradons. Six référen¬

cé sections from Dagestan, Chechnya, Kabarda

and the Minerai Water District were examined

(Fig. 1). They contain carbonate and terrigenous

faciès of the marine Lower Cretaceous (Ber-

riasian to Albian).

The géologie history of the région \a considered

in voluminous literature, with the early stage of

its development being analysed both from the

positions of classical fixism, and on the basis of

more récent mobijistic ideas.

The fixisi conception States that the Caucasus

was developing according to the classic geosyncli-

ne schemc, with the principal structural éléments

inherited from the end of the Palaeozoic-begin-

ning of the Mesozoic (Shevehenko Ik Re/anov

1978; Sholpo 1978). The mobilistic models pré¬

sent the geodynamie évolution of the Caucasian

région as rcsulcing from continental plates cru-

shing and moving apart, and rhe Benioff zones

rifting and subsequently migrating southwards

(Khain 1975; Adamiya ef ^ 7 /. 1982).

The analyses of the lichofacics spatial divisions

and thicknes.s of the Lower Cretaceous rocks,

hâve revealed the principal structures forming

the frame of the North Caucasian Région

(Sholpo 1978): (1) ihe elevaied Southern margin

of the Scythian Plate, conjugated with the trans¬

versal Sravropol high; (2) an intensive submer-

gence zone, spatiall}- concurrent with the

Terek-Caspian pied mont trough; (5) the éléva¬

tion of rhe Créât Caiic.isus (Fig. 1).

The nature of these structures is înterpreted in

different wavs. Some aurhors regard the zone of

the Grcat Caucasus as an inherited horsr-aniicli-

norium Mesozüic (Shevehenko îk Rezanov 1978;

Sholpo 1978), others - as an islaud arc (Khain

1975; Adamiya et ///. 1982). The Terek-Caspian

trough is accordingly interpreted as a geosyncline

axial zone or a marginal island-arc basin.

For our reconstructions, ir is important to note,

that irrespective of palaeotectonic inrerprera-

tions, two geomorphologically distinct sourcc-

lands, the northern and the Southern ones exist

in the Early Cretaceous, with an intermediate

zone of intensive submergence; chis latter one

acting as an area of active marine sédimentation

in the Early Cretaceous. The Mesozoic palaeo-

geography of rhe North Caucasus is generally

being analysed at rhe Icvel of major sedimenta-

tion-tecionic cycles, frequently uniting several

géologie periods and epochs (Khain 1968;

Doiduev 1989). Konyukhov & Olenin (1955)

and Konyukhov (1961) recognised an indepen-

dent Lower Cretaceous -Stage in the géologie

development of the eascern Cis-Caucasia; rhis is

pcculiar for a prolonged transgression, that has

started in the Berriasian and continued through

the Late Albian. Carbonaie-tcrrigcnous sédimen¬

tation prevailed durliig the early stage of the

Lower Cretaceous transgression (Berriasian-

Valanginian). Terrigenous deposits are characte-

riscic of the Barremian, Aprian and Albian.

The détermination ot the terrigenous inlTow

sources m the Cis-Caucasian Basin présents one

of the debatabic probicms for the Mesozoic

palaeogeography of the Norrh Caucasus. This

problem is discusscd in detail in a number of

important papers on the litbology of the

Mesozoic sedimentary complexes' from the

région, but the authors hâve different conclu¬

sions. Konyukhov (1961) considered the North¬

ern Land to hâve been the principal distributive

province during ihe wholc of the Lower

Cretaceous. Grossgeim (1961) deed the éléva¬

tions ol the Great Cauca.süS as the main distiibu-

tivc province. Expanding Grossgeiins scheme

(1961), Sholpo (1978) supposes, thaï in the

Callovian, rhe Caucasus ha.s undergonc active

érosion, that has practically .sioppcd in the

Ncocomian, resumed in ihe lare Barremiun and

reached its maximum in the Aptian and Albian.

In thi.s paper, the authors gor some addiriunal

palacogeographic information while analysing

the data on scalar magnetic cliaracteristics of the

Lower Cretaceous beds from rhe North Cau¬

casus. The petramagnetic data Ict us to carry out

the dccailed analyse.s of sédimentation in the

Early Cretaceous, to specify the importance of

the northern and .Southern distributive provinces

and 10 evaluate the changes of the palaeogeoche-

rnical conditions in die course of transgression

development.

366

GEODIVERSITAS • 1999 • 21 (3)

Magnetic properties of Early Cretaceous in Cis-Caucasia

40“ 42“ 44* 46”

Fig. 1. — Location map. Sections: 1, Kislovodsk City; 2. the Baksan River; 3. the Urukh River; 4, the Assa River; 5, Gergebil Village;

6, Akusha Village. I, the Southern margin of the Scythian Plate (Stavropol High); II. the Terek-Caspian piedmont trough; III, élévation

of the Great Caucasus.

RESULTS

Magnetic measuiemcnts oF the rocks from 1500

stratigraphie Icvels werc performed in six Lower

Cretaceous reference sections (Fig. !). Petro-

magnetic sampling from rwo sections (Kis¬

lovodsk and Gergebil) wa.s diiplicared in the

adjacent outerops of the same âge. Various fades

were examined; limestones, maris, sandstones,

alcurolices and clays, A significanr speerrum of

magnetic features was analysed in the course of

laboratory experiments: magnetic susceptibility

(k), natural rémanent magnétisation (Jn), réma¬

nent saturation magnétisation (Jrs), destructive

field of rémanent saturation magnétisation

(H’es), and magnetic susceptibility measured

upon heating tbe rocks up ro 500° in air

medium (k^). The variation^ in the dk = k^-k

parameter reflect the concentration changes of

initially nonmagnetic iron sulphides. Pyrite and

marcasitc change into magnecite upon heating,

which resulrs in increasing magnetic suscepeihi-

lity. Thus, dk increase reflects the contents of

newly generated magnetite, and conscqucntly,

the concentrations of original FeSj.

The data summari.sed hâve shown many magne¬

tic characteristics to render generally similar

information. To avoid the unnecessary duplica¬

tion, only the k and dk parameters are used in

the présent paper.

Opiical meihods and thermodifferential analyses

hâve dcmonstraled dctrital magnerite to bc the

principal magnetic medium in the bulk of

samples. Its présence is diagnoscd in thermoma-

gnctic curves from disappearance of remanetir

magnétisation around 580 (magnetite Curie

point) (Fig. 2A-C). Magnetic satuiaiions ol die

samples hâve revealcd the magnetically mild

GEODIVERSITAS • 1999 * 21 (3)

367

Guzhikov A. Y. & Molostovsky E. A.

Fig. 2. — Results of magneto-mineralogic analyses for the Lower Cretaceous deposits from the North Caucasus.

Thermodemagnetisation curves: A, clay (Aptian, Gergebi! Village); B, llmeslone (Haulerivian, Gergebil Village); C. differential ther-

momagnetic analysis curve for aleurolite (Hauterivian, lhe Baksan River): D. magnelic saturation and démagnétisation curves; I, for

aleurolite (Berriasian, the Assa River); II. for sandstone (Barremian, Akusha Village).

phase Hs = 32-64 A/m, H’cs = 24-50 inagnetite

(Fig. 2D). The data of immersional analyses tes-

tify to allorhigenic nature of magnetite. The

coarsest Fe^O^ grains are angrilar and possess clear

traces of transportation by water; .scratches and

hatching on the sides and edges.

GrossgcinVs data (1961) confirm the conclusion,

that magnetic features ol the Lower Cretaceous

beds from the Cis-Caucasia were controlled

mainly by detrital magnetism.

Carbonate beds are peculiar for extreniely low

magnetism. Terrigenous complex is characterised

by considérable variations in magnetic suscepti-

biliries. Their levels are pracrically independent

on rock lirhologies or stmctural-textural features,

but are generally determined by the spatial-struc-

tural positions of the sections and by the strati¬

graphie positions of the scquences.

According to its petromagnetic properties, the

Lower Cretaceous terrigenous complex from the

368

GEODIVERSITAS • 1999 • 21 (3)

Magnetic properties of Early Cretaceous in Cis-Caucasia

k

(10’^SI units)

Fig. 3. — Palaeontologic and petromagnetic corrélations of the Hauterivian deposits from the North Caucasus. a, corrélation lines

according to palaeontological data; b, idem according to petromagnetic data; c, petromagnetic intervals highiy magnetic; d, idem low

magnetic. For legend of lithology and gap, see Appendix 1.

GEODIVERSITAS • 1999 • 21 (3)

369

Guzhikov A. Y. & Molostovsky E. A.

North Caucasas may bc divided into two distinct

parts (Appendixes 1-6) in ail the sections, extept

the Kislovodsk one (Appendix l). The Hauce-

rivian-Rarremian becis stand ouc againsi rhc

general background due to higher magnetism

and great dispersion oF magnetic values.

Alternaring groups of highiy and low magnetic

layers are retognised wirhin rhe sections, with the

thickness of 10 to 100 m and the magnitudes of

Jn and k varying bettveen 1-65.HP ST units and

0.2-3.10 -^ A/m, rcspccrivcly.

A certain scqucnce may be outlined in distribu¬

tion of fhc petromagnetic intervals over the stra¬

tigraphie section: the highiy magnetic intervals

correspond to tlic lower parts of biozones or sub¬

stages, and the low magnetic ones-to the upper

parts. Thus, ail the Hauterivian biozones (except

the Acanthodhvm radiatxu one) and Barremian

substages correspond to binomial petromagnetic

rhythms (PR), with the boundaries defined front

sharp (by the factors ot mo, three or more) diffé¬

rences in Jn and k values (Appendixes 1-6).

The numher of rliythms and the thicknes.s are

not constant and dépend on ihe section comple-

teness and sédimentation races in various structu-

ral-facies zones. On the basis of ail the

considered data, at least three petromagnetic

rhythms are recognised in the Hauterivian

(Fig. 3). Ail of them occupy somc dcfinicc strati¬

graphie positions and may be used for dccailed

section divisions and corrélations, évaluation of

wa.shoucs and sédimentation gaps (Fig. 3).

Another peculiarity of the Hauccrivian-

Barrcmian scdimencation consists in distinct

structural-spatial différentiation of the sédiments

according to their magnetic properties.

The littoral-marine sandstoncs froin the

Hauterivian Stage of the Minerai Water Région,

are characterised by low and uniform magnetism

(k = 0-3.10’^ SI unies). The Hauterivian bed

magnetism increases up to 10-20.10SI units to

the south-easf, in the Baksan Sectiori The values

reach their maxima in the Urukh River Basin,

where mosr of the samples having k varying het-

ween 15'50.10'^ SI units over the whole of rhe

Hauterivian and Barremian sections. In souih-

eastern Dagestan, the highiy magnetic horizons

are separated and localised in fairly narrow inter¬

vals of the section (Fig. 4).

The Cis-Caucasian Aptian and Alhian bed.s form

an independent lithological-magnetic complex,

sharply different from rhe Hauterivian-

Barremian one by irs low magnetism (Fig. 4). In

the Aptian deposits, the k values vary within 1-

12 .lO '^ SI units withour any significant différen¬

tiation over rhe section.

The Alhian deposits are even lower magnetic (k =

1 -10.10 *' SI units). Neverrheless, in Dagescan

sections, four binomial petromagnetic rhythms

may bc outlined from vatiadons in magnetic sus-

cepribility. In the référencé section of the Albian

near the Akusha Village, the First rhythm (K 1)

covers the lower and the middie substages, the

K 2 — the Dipolocrras rmunum-Hysterocems vari-

cosum zones, the K 3 — the Mortaniceras mjîatum

zone, and the K 4 — rhe SloUczkaia ciispar zone

(appendix 6). In the lower rhythm, the boundary

bcTV'ecn the low and moderately magnetic inter¬

vals coïncides with the O. royssianumIA. interme-

dim biozone boundary.

A pcciiliar feature of the Aptian-Albiun petroma¬

gnetic cornplex consists in a sharp increa.se of the

rock magnetic susceptibilities in certain stratigra¬

phie intervals, upon heaüng up to 500".

The Lower Aptian and lowermosr Middie Aptian

(rhe Epicbelontcey'as subnodosocostatum zone] beds

do nof rcvcal any significant increasc in magnetic

susceptibility (Fig. 4).

An anomalous burst of dk values (up to 450.10 ^

SI units) is associated in ail the sections with the

boundary beeween the Middie Aptian zones

E, sulmodosocostatum and Parakoplites melchioris

(Fig. 4).

The thermokappamerric diagrams for the depo¬

sits from the P. mekhiorh zone, Upper Aptian

and Albian, have individual pcculiaritics in cach

of chc sections (Fig. 4).

In the vicinity of Kislovodsk, high dk values (up

to 400.10'^ SI units) are recorded only in the

lower part of rhe 7? melchioris zone.

In the basin of the Urukh, high values of magne¬

tic susceptibility are characceristic both, of the

Upper Aprian and of the Alhian complexes (dk =

150-450-10'^ SI units and dk = 100-400.10 ^ SI

units, respeciivdy).

In Dagestan, anormal dlc values arc charactcri.stic

of the uppetmost Aptian and of the Albian.

However, in the section near Gergebil, the

370

GEODIVERSITAS • 1999 • 21 (3)

Guzhikov A. Y. &c Molostovsky E. A.

Albian is markcd with higher dk values (to

300.10'^ SI Linits)» than tlie upper Aprian, while

the reverse is observed iiear Akusha.

Variations in magnctic susceptibility increase are

associated with the paJaeontological boundaries.

Thus, in the AJbian Section from Akusha, rhe

smoothed dk curve (the dk curve was smoothed

by means of calculating dte sJiding arithmctic

mean from five samples, at a step ofone samplc,

Appendix 6) demonstrated distinct rhythms,

while ihree of its intervals with the dk > dkav

stratigraphically coïncide with the zones

PseudostmneraTiii eoelentata^Oxytropidocems roys-

siamim, H. orbignyi'H. varkosïmi and Stoliczkaia

dispar^ respectively.

As seen in Figure 4, the values ol k and dk para-

meters reveal clear inverse rclationship: the high-

ly magnetic I iauterivian-Barremian parts of the

sections are characterized by minimal increases of

magnetic susceptibility; on ihe contr.ary, rhe

highest dk values are recorded in the low inagne-

tic Aptian-Albian sequences.

PALAEOGEOGRAPHIC INTERPRETATION

OF THE DATA

Rock magnetic propetties are primarily determi-

ned by the compositions and concentrations of

allothigenic or/and authigenic ferromagnetic

minerais; ihese vary depending on sédimentation

settings. From this follow the previously formu-

latcd postulâtes for the géologie interprétation of

petromagnetic data (Molostovsky 1986;

Guzhikov Molostovsk)' 1995).

The following iheses are relevant to the présent

theme:

1, The magnétisation iniensity of sedimentary

rocks, contuining allothigenic ferromagneticS) is

determined by tbe pulaeogeographic and tecionic

factors, controlling Ivaring, drifting and précipi¬

tation of terrigenous marerials, Petromagnetic

différentiation of the la^^ers in a stratigraphie sec¬

tion reflects déposition rhythms and changing

sédimentation settings, resuiting from geodyna-

mic reconstructions in baring areas, and, mostly,

from the sourceland changes.

2. Variations in the dk parameter adcquately

reflect changing geochemical settings and hydro-

gen-sulphide contamination of the bortom silts

or its absence.

Complex analyses of the magnetic properties,

and of the materials on Hthofacies stratigraphie

distrihutions on fossil biocoenoses, textural-

structural feattites of the rocks, allow co obtain a

fairly complété idea of rhe évolution of sédimen¬

tation sctting.s in rhe Cls-Caucusian Basin during

die Early Crctaccous.

Ail rhe data combined, provide the grounds for

recognising the independent Lower Crciaceous

step in rhe géologie development of rhe North

Caucasian Région, comprising several major

stages, each one from 10.5 to 27.^ million ycars

long.

The firsr stage, eqtiivvdenr to the Berriasian and

Valanginian, coïncides with the bcginnlng of a

major transgression, marked by chiefly carbonare

sédimentation. Déposition took place in the set-

riags of a relariveJy shaJlow and wcll-oxygcnated

warm basin (Konyukbov ^ Olcnin 1955;

Konyukhov 1961; Khain 1968). The limited ter¬

rigenous inpur and cxrrcmcly low magneri.srn of

the rocks tesdly co chc lowland terrain in pro¬

bable soLircclands. and low magnetism of the

source rocks.

The Hauterivian bas opened a new stage in the

Ëariy Creraceous sédimentation cycle. The

consistent sea transgression northwards, coinci-

ded with lectoiiic activation of the Great

Caucasus and élévation of the Southern margin

of the Scyrhian Plate.

The increased magnetism of the Haurerivian-

Barremian part of the section, indicate.s, chat the

principal sourceland did not lie in the Northern

Land with ihe low magnetic sedimentary cover

being washed ouc, but was situated in rhe Great

Caucasus cerntory, characieriscd by wide deve¬

lopment of the Upper Palaeozoic and Jurassic

intrusions and of the dike complex of basites

(Afanasycv 1968).

Jiidging from the characters of petromagnetic

sections, the rerntory of the Central Caucasus

was the principal magnetic maierial supplier to

rhe Lower Crctaceous basin. The bulle of ihe

magnetic terrigenous inpur was accumulated

wilhin the Oseiin syncline, in che basins of the

Baksan and Urukh. The eastern part of the Great

372

GEODIVERSITAS • 1999 • 21 (3)

Magnetic properties of Early Cretaceous in Cîs-Caucasia

Caucasus was less important in this respect. The

Western Caucasus, with its granicoid intrusions

of Malkinskaya group, did not exert any obvious

influence on thc sédimentation in the Cis-

Caucasian Basin. The Southern part of the

Scythian Plate and thc adjacent Stavropol projec¬

tion (Fig. 1) served as the main distributive pro¬

vinces for the western part of the Central

Cis-Caucasia. l’his is indicated by low and uni-

form magnétisation of rhe Hauterivian arkoses

from the Minerai Water District (Fig. 4), practi-

cally devoid of ferromagnetic matetials.

The petromagnetic differentiarion of the sédi¬

ments over the stratigraphie section, being adé¬

quate to sédimentation rhythms, testifies to

pulsatory characrer of déposition and uccasional

changes of sourcclands. Chronologie coïncidences

of thc petromagnetic rhythms and biov.ones are

indicative of the event nature of magnetic and

palaeontologic buundaric.s, and of iheir paragene-

ric dependence on the régional geodynamic

events. Thls inference is con.sistent with the idea

of thc funaional dependence of many biocoeno-

tic shifts upon changing sédimentation settings

(Zhizhhcenko l969;Zubakov 1990).

Stabili.sing rectonic settings in rhe région of the

Créât Caucasus at che beginning of tlie Aptian,

bave led to rapid decrease in lerromagnetic inpui

to ihe Cis-Caucasian Basin and, consequcnily, lo

sharp magnétisation decrea.se in borrom sédi¬

ments. Starting from the Aptian, the Southern

Land was no longer important as a sourceland.

Thus, during the las'i stage of the Aptian-Albian

sédimentation, the Northern Land, structurally

linked to the margin of rhe Scythian Plarc>

bccomes the principal distributive province,

rhe Aptian sequence Ls practicallv not difteren-

tiated according to scalar magnetic characteris-

tics, which, imder certain assumptions, may be

interprered as indicative of relarively stable tecto-

nic settings. Judging from insignificant magne-

rism variations in rhe Albian sections, some

activation bas probably laken place in the end of

the Early Cretaceous {Appcndixe.s 5, b, Fig. 4).

The régional redo.v potenrial réduction of déposi¬

tion environment, constirutes a distinctive fea-

ture of the Aptian-Albian sédimentation within

che Norch Caucasus. Anormally high concentra¬

tions of disseminated pyrite, reliably recorded

from sharp k, incrcases, arc observed in ail the

sections studied, and testiiy to periodical conta¬

minations of the bottom scdinients in the Cis-

Caucasia with hydrogen sulfide in the end of the

Aptian [P. mekhiom zone and the upper substa¬

ge) and thc Albian.

The magnitudes and durations of thcsc process

manifestations varied within widc ranges.

Various inrcnsiiies of dk in distant sections of the

same âges (Fig. 4) are indicative of the changes in

redox settings to hâve been peculiar in each of

the faciès zone (Fig. 4). In the Minerai Water

District, ihe hydrogen-sulphide environment

existed tÜI thc middle of che P. melch'wm time.

Within thc Osetiu syticlinc (thc Urukli River)

and Dagestan. it persisted rill the end of thc

Albian.

The coincidences of thermokapp;unecric and

biostratigraphic nuits, registered in the Aptian-

Albian beds from Dagestan (Appendixes 5, 6),

seem quite logical. The changes in ihe redox

potenrial of rhe déposition environment, as well

as che hydrogen-.sulphide contamination, are

known to be controllcd by palaeoclimatc feaiures

and cLisiatic oscillations. The same factors

influence biota évolution and ihe relaiionship

between planktunic and benthic organîsms in the

palaeobasin. Thu.s, vertical distributions of the

dks, docuntenr tfie changes of fimnal sequences

within the sections considered.

As shown in Ingure 4, the values of k and dk

demonsiratc obvious reverse rclaiionships: the

highly magnetic Hauterivian-Barremian parts ol

dic sections are characcerised by minimal increases

of magnetic susceptibllity, while, on the contraiy,

the highest dk values are recorded in the low

magnetic Aptian-Albian sequences. The négative

corrélations berween the k and dk diagrams are

accounred ft)r by the oxidising environment in the

palacübasin during the periods of tectonic activa¬

tions, and by the favourable conditions for redu-

cing settings in rhe deep parts of the réservoir

during the periods of tectonic stabilisation.

CONCLUSION

The set of géologie and petromagnetic data pro¬

vides the grounds for subdividing the Lower

GEODIVERSITAS • 1999 • 21 (3)

373

Guzhikov A. Y. & Molostovsky E. A.

Cretaceous Stage in the development of the

North Caucasian Région into three steps, rcflec-

ting peculiar geodynamic and geochemical set-

rings in varions intervals of géologie time.

The fîrst onc-, the Rerriasian-Valanginian srep, is

peculiar for mainly carbonate déposition. The

insignificant amouiii of détritus in the Berriasian

deposits. and its alniost complote absence from

the Valanginian scquences, are indiaitive ol quiet

palaeorectonic setiings and low érosion bases

both, in the Southern» and the Northern lands.

The second, the Haurerivian-Rarromian step,

was characrerised by intensive terrigenoas drift

against the hackground of general tcctonic acti¬

vation. The central part of the Great Caucasus

becomes then one ofibe principal sourcclands,

with fairly cornmonly dcvelopcd granité and

basitc bodies — the main suppliers ol magnetic

matcrials to the région ol marine accumulation.

The Hauterivian-Barremian tectonic activation

of the (jreat Caucasus might be a régional rcflcc-

tion of the final stage ol the Lare Kimmerian lec-

togencsis phase (Kunin & Sardonnilcov 1976).

The thifd one, the Aprian-Albian srep, coïncides

with tectonic stabilisation ol rhe région assoda-

ted with lurther norrhward transgression deve-

lopmenr. The Gréai Caucasus chen has probably

lost its importance as a supplier of terrigenous

material, and the marginal régions of the

Scythian Plate have once more becomc the prin¬

cipal distributive provinces. During that stage,

the déposition was taking place in reducing

hydrogen-sulphide settingvS. A correspondence

can’t be ruled out betw'een the noied peculiarify

of the Lower Cretaceous palaeogeochcmistry in

the basin, and the global anoxie events at rhe

Early/Lace Cretaceous boundary (Dale et ai

1992).

Acknowledgements

The authors are grateful to Prof. Van der Zwan

(The Netherlands) for his helpfui review on the

first drah of the papen

REFERENCES

Adamiya Sh. A., Asanidze B. Z. & Pechersky D. M.

1982. — Geodynamics of the Caucasus (an

aitempt ol palinspastic reconstructions): 23-37 fin

Rusiian]. hi Sheina l. P. (ed.), The Cauiosus geody-

namkprobknn. Na^lka^ Moscow-

Alanasycv G. D- 1968. — MaginatLsm development

.stages. 550-554 |in Ru.sskn], tn Andruschuk V. L.

(ea.). Ckologv of ihv USSR. The North Caucasus.

Pan I. Géologie dcscripnon. Ncdra, Moscoxv.

Paie L. A., Chaitanya S.. Block J., Wilson M. 6: Wall

J. 1992. -— An anojcit event at the Albian-

Cenonianian boundary ihe Fish Scalc Market Bed,

lUirthcrn Alberta, Canada- Paiatogeography,

Palfieoiiimatolù^. Pt/laeaecokgi 92 iX-ZY 1.^9^166.

Üorducv 5- I. 1989. — Meso-Cenozoic geodynamics

in the Greater CaiicaHUî: 82-02 [in Russian), /w

Sheina L.P. (ed.), The Cdtuaius geodv^idmics.

Moscow, Nauka .

Grossgeini V. A. 1961. — Hisiéïry of terrigenous

minerais in the Mesozoie and Ccnozoïc from the

North Caucasus and Cis-Caucasia. VNIGRI

Proceaiirig 180, 376 p. [in Russian].

Guzhikov A. Y. & Molostovsky K A. 1995 —

Sirarigraphic significance ol .scalar magnede charac-

terisrics of sedimenrary rocks (methodical aspects).

MOIP BuHethu Geologital dcparimcnc 70 (1):

32-41 |in Russian).

Flarland W. B.. Cox A. V.. LIewcIlvn l\ G., Pickton

C. A. G., Smith A. G. & Walters R. 1982. — A

géologie time Haie. Cambridge University Press,

Cambridge, England, I28p,

Khain V. L. 1968. — Géologie development history;

676-700 fin Russian), /// Andruschuk V. L. (ed.),

Gealogÿ of tbe USSR. d'Iie North Caucasus. Part l.

Géologie desetiption. Nedra, Moscow.

— 1975. — Prindp.îl srages in the tcctonic-magmatic

development of the Caucasus: an artempr ol geody-

namic interprétation. Geotectonica (1): 13-27 [in

Russian].

Konyukhov î. A. 1961. — Lirhoiog)' of the Mesozoie

deposits from the Eastern Cis-CjiutaNi.i as relared to

oil and gas conrrnis, //; Brod I. O. (ed.). Gcology

and oil and gas contents in the south ol the USSR.

Strarigraphy and Üthology of rhe oÜ- and gas-bca-

ring scquences from the Ea.stcrn Cis-Caucasia.

KYLiGE Prmcfdingt Leningrad Branch, Leningrad

.3: 7-398 |iji Ru.-isian].

Konyukhov 1. A. & Olenin B. V. 1955. —

Palcogeography of the northerti slope of the Main

Caucasian Range and rhe: E-astern Cis-Gaucasia in

the l.ower Crctaceou.s epoch, Sovjetskaya geologiya

(451:27-38 (in Russian],

Kunin N. Ya. & Sardonnikov N. M. I9'76. — Global

cycles in tcctonic jnotion.s. MOIP Bulletin,

Geological deparrment 51 (3): 5-27 [in Rus.sian].

Molüsruvsky V. A. 1986. — Rock scalar magnetic

cbaracicristics as indicaior.s of .sédimentation condi¬

tions: 180-196, [in RussianJ, in Kumpan A. S.

(ed.). Rock wagncfisni use in geological survey.

Nedra, Lcningiad.

Shevehenko V. I. 6c Rezanov 1. A. 1978. —

374

GEODIVERSITAS • 1999 • 21 (3)

Magnetic properties of Early Cretaceous in Cis-Caucasia

Development regularities of the géosynclinal région

from the south of the European part of the USSR.

News of higher educational institution. Geology and

exploration (12): 3-14 [in Russian].

Sholpo V. N. 1978. —Alpine geodynamics in the Great

Caucasus. Nauka, Moscow, 176 p. [in Russian].

Zhizhhcenko B. P. 1969. — Methods for stratigraphie

researh in oil and gas-bearing régions. Nedra,

Moscow, 373 p. [in Russian].

Zubakov V. A. 1990. — Global climatic events in the

Neogene. Gidrometeoizdat, Leningrad, 220 p. [in

Russian].

Submitted for publication on 22 January 1997;

accepted on 27 September 1998.

GEODIVERSITAS • 1999 • 21 (3)

375

Magnetic properties of Early Cretaceous in Cis-Caucasia

APPENDIX

C/D

c ï

ü ^

ZE

0

20

40 ■

60

80

100

120 ■

140

160

180

200

300 -

0

O)

CO

0

O)

0

CO

3

CO

Zone

Albian

upp

low

Hypacanthoplites

_ jacobi

Acanthohopliîes

nolani

Parahoplites

mefchioris

Dufrenoya furcata

D. deshayesi

D. weissi

C.securiformis

Imerites giraudi

Crioceratites

nolani

Epichebniceras

subnodosocosîatum

Holcodiscus kiliani

Acanthodiscus radiatus

Valanginian

DD

O

k(io®si

units)

0 20 0

Ak(10'^SI units)

200

300

. I I

400

Increase of

magnetic

susceptibility

Magnetic

susceptibility

Clays

Aleurolites

Sandstones

Appendix 1 . — Petromagnetic characteristics of the Hauterivian-Aptian deposits from Kislovodsk Section.

GEODIVERSITAS • 1999 • 21 (3)

377

Guzhikov A. Y. & Molostovsky E. A.

A

38i

Magnecic properties of Early Cretaceous in Cis-Caucasia

B

Appendix 4. — A, B, petromagnetic characteristics of the Berriasian-Albian deposits from Urukh Section. For legend of llthology and

gap, see Appendix 1.

GEODIVERSITAS • 1999 • 21 (3)

(Subzone)

Hysteroceras

orbignyi

Dipoloceras

cristatum

EuhopHtes lauius

Anahopates

intermediüs

Hop/ftes spêtfii

Lyejli^

Leymerlêila

tardefurcêta

*•§_ Hypacanthopliles

=3

iHïSitTa

melchioris

Epicheloniœms

subnodo$(xostatum

D. furcata

0 I D. deshayesi

O

I D. weissi

n Hemihophtes

ridzewskyi

0 Colchidiîes

g; securiformis

=3 +

fmerites

giraudi

0 Holcodiscus

5

Appendix 6. — A, B, I

and gap, see Appendi:

385

Régional magnetic zonality scheme for the

Berriasian-lower Aptian from the North

Caucasus

KEYWORDS

Magnetostratigraphy,

polarity,

rémanent mametisation,

Lower Cretaceous,

Caucasus.

MOTS CL^

Magnétostratigraphie,

polarité,

aimantation rémanente,

Crétacé inférieur,

Caucase.

Andrey Yu. GUZHIKOV & Vital! N. EREMIN

Institute of Geology, Saratov State University,

Moskovskaya Street, 161, Saratov 410750 (Russia)

guzhikovay@info.sgu.ru

Guzhikov A. Yu. & Eremin V. N. 1999. — Régional magnetic zonality scheme for the

Berriasian-lower Aptian from the North Caucasus, in Crasquin-Soleau S. & De V\/ever P.

(eds), Peri-Tethys: stratigraphie corrélations 3. Geodiversitas 21 (3) ; 387-406.

ABSTRACT

Palaeomagneric rescarch was carried out in rhe Nordi Caucasas, Azerbaijan,

Mouncainous Mangyshlak and Central Kopetdag. The ten most complété

marine sections of the Lower Cretaceous werc selected. They provided

opportunity to make reliable references of palaeomagnetic coIumn.s to the

ammonite zones from the general stratigraphie scale. About 7500 oriented

samples were selected from outerops. The data on rhe Berriasian-lower

Aptian deposits magnetism in the North Caucasus and the Western Central

Asia comhincd with other aurhors data provide the material for révision of

Neocomian palaeomagnetic structure.

RÉSUMÉ

Zonation magnétique régionale pour le Bérriaüen-Aptien inférieur du Nord

Caucase.

Des recherches paléomagnériques ont été poursuivies dans le Nord Caucase,

en Azerbaïdjan, dans les montagnes du Mangyslhak et dans le Kopetdag cen¬

tral. Les dix coupes les plus complètes du Crétacé inférieur ont été sélection¬

nées. Elles offrent la possibilirc de dresser des colonnes palcomagnétiques de

référence, corrclable.s aux échelles standard d'ammonites. Environ

7500 échantillons orientés ont été prélevés. Les données sur le magnétisme

des dépôts du Berriasien-Aptien inférieur dans le Nord Caucase et l’Asie cen¬

trale de rOuest, combinées avec les données bibliographiques, permettent

une révision de la structure paléomagnétique du Néoconiien.

GEODIVERSITAS • 1999 • 21 (3)

387

Guzhikov A. Yu. & Eremin V. N.

INTRODUCTION

The maicrials obtained consiiruted the basis for a

composite section of the Berriasian-lower Aptian

of the North Caucasus; four relarively large

magnetozoncs wiih ahernating, normal and

mainly reverse polancy were recorded within this

section, fheir stratigraphie ranges (stage, sub-

stage) correspond to ihe onhozones from the

general palaeomagnctic seule (Anonymous

1992). Each orrhozoae ts characterised by a

rather cornplicated .structure owing ro subordina-

te sub- and microzones of opposite polarities.

Palaeomagnctic units, which coiurary to

palaeontological ones, are stable on global scale,

in certain cases may be used as a measunng rule

for parallélisations of stratigraphie scales from

distant régions.

Magnetostratigraphic corrélation of the

Berriasian deposits from the Caucasus and the

stratotype région has made it possible to reveal

the interrelaiions benveen the ammonite scales

from the two régions, and furrhermorc, ro esta-

blish the approxirnate locations of calpionellid-

zone boundaries in the sections on the Caucasus.

Correlalioti.s ot magnetostratigraphic sections

from Mangyshlak, the northern Mediterranean

and the English hypostratorype made it possible

to consider the corrélations between the ammo¬

nite and calpionellid scales of the Valanginian.

WORKING METHODS

The study was focuscd on the most complété

Berriasian-lower Aptian marine sections from the

North Caucasus and Central Kopetdag (Fig. 1)

providing reliable refercncing of the palaeoma-

gnetic Cülumns to the ammonite zones in the

general stratigraphie scale.

The sections were commonly described in coopé¬

ration with hiostratigraphers, which allowed

strict géologie and palaeonrologic control of the

palaeomagnctic arrangements.

Frequencies of the oriented sample sélection were

determincd by ihc thicknesses of elle deposits

studied. Sampling intervals varied from 0.5 to

3.5 m in the sections tlirough fblded areas and

from 0.2 to 0.75 m in the platform.

As a rule, onc sample was selectcd from each

stratigraphie levcl; later on. it was sawcd in 4-

6 tubes, 24 or 20 mm on edges.

Palaco- and pcrromagnetic studies were accom-

panied by the standard complex of laboratory

Work. Magnetic suscepiibilities (k) and natural

remanenr magnétisation (NRM. Jn) were raeasu-

red; magnetic clcaning was carried ont with tem¬

pératures and alternating magnetic fîelds; normal

mugnetisarion curves were drawn with subse-

quenr measuring of ihc rémanent saturation

magnétisation (Jrs), détermination of satunation

Rcids (Hs) and destroying fields of remarient

saturation magnétisation (H es). Thermo-

magnetic and differcniial therniomagnetic ana¬

lyses (TMA and DTMA) were widcly used to

diagnose magnetic phases. A number of samples

from each section were studied by means of op-

tical miucralogy.

Rémanent magnétisations were mcasured by

lON-l V JR-3> jR-4 devices, magnetic susceptibi-

lities-by IMV-2 and KT-5.

Température magnetic cleantng was performed

in rhe non-magnetic Rirnaces within four or five-

layer permalloy screens or within a llclmholtz

ring unit. Successive hearing was carried out in

the range of 100-500 ‘'C at température incré¬

ment of 50-100 ”C during one to lour hours, To

consider possible rock biasing. at Ic.ist rwo cubes

from each sample were put into tlic lurnace:

chose with imituaJly antiihetic oncnt.'itions in ail

the three componcnc? of magnétisation vectors.

Sorne samples underwent cleaning with alterna¬

ting magnetic ficld within Flelmholtz ring Sys¬

tem in the range of 16-40.10 -'' A/m.

The analyses of normal magnétisation parame-

ters (Hs, Jrs, HTs) and the TMA and D l'MA

data (Sec fig. 2 in Guzhilov & Molostovsicy, this

volume) make it possible to conclude, thar

magneti.sation of the rocks studied, was caused

mainly by magiietite. li.s pre.sence is easily dia-

gnosed by means of thermomagneiic curves:

rémanent magnétisation vanishes from the

région of 580 ”C (magnetite Curie point). The

sample magnetic saturations hâve rcvcaled the

magncticallv soft phase typical of tlnely dispersed

magnetite (Hs = 32-64.10*^ A/m, ll'c.s = 24-

50.'i0 'A/m).

Zijderveld diagrams were constructed for com-

388

GEODtVERSITAS • 1999 • 21 (3)

Lower Cretaceous magnetostratigraphy in Caucasus

40° 42° 44° 46°

S Borderof States p ~ '1 Borderof Russian régions Mountainsranges | 0 | Sections

Fig. 1. — Location map. I, Great Caucasus; II, Balkhan; III, Kopet-Dag. Sections: 1, Kislovodsk City; 2, the Baksan River; 3, the

Urukh River; 4. the Assa River; 5, Gergebil Village; 6, Akusha Village; 7, Nardaran Village (Northern Azerbaijan); 8, Tyuyesu

Mountains (Mangyshlak); 9, the Segiz-Yab River (Central Kopetdag).

GEODIVERSITAS • 1999 • 21 (3)

^«0

Guzhikov A. Yu. &C Eremin V. N.

ponent analyses of rémanent magnétisation vec-

tors. The rypical diagram presented in Figure 3.

testifies lo the siabiliiy of resulting Jn irends:

over ihe whole teinpcratiife interval after des¬

truction of rhc secondary componcnts, thc vector

changes along the straight line directed tcnvards

the centre of co-ordinates-

Magnétisation of the rocks considered, is charac-

terised by cwo components: the primary onc,

revcaling tes treiid after mild thermal cleaning

and preserving it up to 500 °C (Fig. 2)v and the

secondary onc. of probable viscous nature. The

latter face is affîrmed by thc majority of Jn vec-

tors clusrenng after in situ measuremenrs about

the trend of rock remagnetisation by the présent

field (Appendix lA). After a sériés of successive

t°- and H'tieanings, the remagnetisation rrends

were regularly clustering in the First quadrant of

thc low'er hcmlsphcrc or in the ihird quadrant ol

the Lipper onc (Appendix IB). These sets were

interpreted ns thc normal and reverse polatity

interval-s, re.spectively.

To substantiate the jn priority, numeroas gcolo-

gic-geophysics criteria and tests were applicd,

which made it possible to judge the age of

magnétisation in major rock complexes. Somc of

thèse indicarions are considered below.

1. Onc of thc important indications of a Jn sign

being rclaied wil h the poUrily of an ancient field,

consists in orientation indcpendence of magnéti¬

sation vector.s upon lithologie-minéralogie charac-

teristics. In dre majorir)^ of rbc- sections srudicd,

the magnétisation crends arc obviously indift’erent

to various rock types (Appendixes 3-8).

2. Another evidence of magnétisation priority

lies in the lack of interrelations between polarity

signs and scalar magneiic characferistics. In

many sections studied, several diverse-polarity

zones were recognised wiihin sequences undifVe-

rentiated with respect to k or Jn. Sinnlar .situa¬

tion is übservcd, for instance, in the Valanginian

beds on the Tyuycsu Mountain (Appendix 3). In

the Barremian section near the village of

Gergebil, on the contrary, a normal polarity zone

embraces both, the weakiy magnetised (k = 3-

10.10 ^ SI unies, Jn - 0.5-1.2.10’Vm), and scron-

gly magnetised (k = 20-50.tO '* SI units, Jn ^

2-4.10 A/m) intervals (Appendix 4).

3. The immersional analyses data show allothige-

nic magnetite lo be présent in the rocks. The

coarsest Fe^O^ varieties hâve anguJar grains with

obvious signs of transporiaiion by water

(scratches and grooves on faces and edges), which

confirms rheir terrigenous origin. To a certain

extent, this arguments for detriral nature of

magnétisation. Firni grounding of this statement

is idenrical to N RM priority proof.

Low values of Kenigsberger ratios (Q = Jn/Ji =

0.05-0.5) and low inter-sample clustering of the

trends of stable NRKi components (k = 5-30),

characteristic of DRM (or PDRM), are regarded

as the indirect palaeomagneiic évidences in

favour of oricntational (or posrorienrational)

genesis of magnétisation.

4. Corrélation of rhe palaeomagnetic structures

of the similar-aged beds from distant hcterofacial

section.s-, may certainly serve as a strong argu¬

ment for substantiating thc gcophysical nature of

magnetozones. The overwhclming majority of

thc magnetozones recognised. meet this criterion

and are laterally craccd in certain stratigraphie

intervals within vaiious lithoJogical-magnctic

lock t\'pes that have been formed in diverse geo-

chemical setrings (Fig. 3). It is piactically impos¬

sible to imagine, that self-rcvcrsal or secondary

rcmagnetisarion processes, able to re.sult in dis-

tortion of NRM polarity, 111 . 1 / be manilcsted

synchronously over vast territories and in rocks

of diverse types. l’hc indication ofextenor corré¬

lation beœmcs cspccially pondérable when sinii-

lar magnetic pobrit)' zone'iare recognised wirhin

similar-aged stratigraphie intervals From the

régions characierised by different géologie histo¬

riés. For exaniple, ihe rever.se polarity subzone

Rjap is recognised in the base of the lower

Aptian substage, both in the North Caucasus

and in the Kopetdag. The comparison.s of the

palaeomagnetic columns from the objccts stu¬

died with the magnetostraiigiaphic sections from

Siberia, Central A.sia, West Europe and other

régions lying apart (Fig. 3), have revealed good

corrélation of the palaeomagnetic data.

Each of the above criteria indircctiy confirms,

but does not prove priority of Jn. An important

evidence jn favour of thes hypothesis, however,

lies in the sum of independenr observations

conforming ro the suggestion of the ancient

nature of NRM.

390

GEODIVERSITAS • 1999 • 21 (3)

Lower Cretaceous magnetostratigraphy in Caucasus

Fig. 2. — Zljderveld diagrams. NRM vector projection in horizontal (I) and vertical planes (II) within lhe sample coordinate System.

Samples: A, clay (Hauterivian, Gergebil Village); B, timestone (Hauterivian. Gergebil Village): C. aJeuroIfte (Berrlasian, the Urukh

River); D. aleurollte (Barremian, Gergebil Village); E. aleurolite (Barremian. the Segiz-Yab River); F, sandstone (Aptian, Kislovodsk

City).

REGIONAL SCHEME OF THE

NEOCOMIAN (BERRIASIAN-LOWER

APTIAN) MAGNETIC ZONALITY

IN THE NORTH CAUCASUS

The working magnetosrratigraphic scheme of the

Lower Cretaceous in the North Cauca-sus (Fig. 3)

is based on palaeoioagnccic study results from

ren outerops of the marine Lower Cretaceous;

their géographie positions are presented in

Figure l. Dr ail sections, the magnetozones reco-

gnised were rcliably rcfcrenccd to the ammonite

zones in the general stratigraphie scale (Fig. 4),

compilcd from the data provided by numerou.s

researchers (Proz-orovsky 1989). On tlie total, the

magnetostratigraphic scheme is characrcrised by

-7500 oriented samples from mure than

1600 stratigraphie levels.

Composite palaeomagnetic columns for each of

the Lower Cretaceous stages are described below.

In conclusion, generalised characteristic of the

régional Neocomian magnetic scheme is presen¬

ted for the North Caucasus.

The Berkiasian SrAGi-,

The Berriasian beds, represenred by alrernating

carbonate (limestones, maris) and terrigenous

(clays, aleurolites) rocks, were studied in the

North Caucasus on the Assa and Urukh rivets

(Eremin 1991) (Fig. 4). In the First section,

Sakharov (1976) has established ail the ammonite

zones of the Berriasian: each of them, ejccepi

Pseudosuhfdanites ponîkus zone, is further subdivi-

ded intü two .subzones. On t(ie Urukh River,

according to the fmds of the corresponding index

species, Tirnovella occitanica, Euthymiceras etithy-

GEODIVERSITAS • 1999 • 21 (3)

391

Guzhikov A. Yu. & Eremin V. N.

Gergebil

Kislovodsk Urukh Village Akusha

City River £») Village

mi and Riasanites tjnsamnsis zones wcrc rccognised

(the P. ponticus lower zone, was not tound there).

The composite Berriasian magnetoscradgraphic

section from the North Caucasian Région

consists ol five alternating subzones: threc oncs

of reverse polarity (R|b, R 2 b, R^b) and cwo of

normal polarity (N|b, N^b) (Eremin 1991)

(Figs 3, 4).

The Vai anginian Stage

Palaeoinagnetic study of the Valanginian beds

was performed in the Trans-Caucasia (northern

Azerbaijan, near the village of Nardaran)

(Eremin & Guzhikov 1991) and in Mang}^shlak

(in dyuye.su Mountains) (Fig. 3, Appendix 3).

1ji the first section, rhe uppermost of the

Babadagslcaya suite was exposed, represented by

terrigcnous-carbonate flysch (maris, clays, aleuro-

lires, sandstoncs). The Valanginian âge of the

rocks was determined on the basis of microfaunal

dara (AJicv 1965).

The Valanginian Stage in Tuyesu Mountains is

represented mostly by fine-grained sandstones.

The two substages are recognised according to

392

GEODIVERSITAS • 1999 • 21 (3)

Lower Cretaceous magnetostratigraphy in Caucasus

Fig. 3. — Régional magnetic ronality scherne lor the Berriasian-lower Aptian from lhe North Caucasus. A. quantity oï sludied strati¬

graphie levels/ThIckness (motres): B, corrélative Unes of biostratigraphlc stages, subslages and zones: C. oorrelative Unes ot palaeo*

magnelic subzones. Absolule ege from Harland et ni. (1982). a. Harland et ait (1962); b. Molosrtovsky & Khramov (1964) and

Khramov (1982); c, Tarduno et. at (1992); d. j, Pospelova (1976); e. l Lowrie. Alvarez efat (1960) and Lowne, ChanneÜ & Alvarez

(1980). f, Grishanov (1984), g, Pechersky (1970) h. Treîyak et ai. (1976), i, Bralower(i967)i k. Guseynov (1988)* m, Channeil etai.

(1979): n. Ramazanov & Dedova (1990). o. Channeil (1967). p. Ramazanov (1987). q. RzhevsKy (1966); r. Pospeiova & Lationova

(1971); s. Besse et ai f19a6). t. Uowrie & Channell (1983); u. Galbrun (1985); v. Eremin (1991). For lilhology, see legend on

Appendjjt 4 .

the macrofaunal complex, including ammonites

(Bogdanova 1983).

The palacomagnetic column of the Mangyshlak

Section consiscs of two subzones: alternating

(RNv) and normal (Nv) polarities. (Fig. 3,

Appendix 3).

The Babadagskaya suite is encompassed by a

major normal polarity magnetozone, complica-

ted by five thin r-intervals (Eremin & Guzhikov

1991) (Fig. 3).

GEODIVERSITAS • 1999 • 21 (3)

393

Guzhikov A. Yu. & Eremin V. N.

The Haui'erivian Stage

The Hauterivian beds were studied on rhe

Baksan and Urukh rivers, near the village ot

Gergebil (Nortli Caucasus) and in the vicinity of

Nardaran Village (norrhern Azerbaijan) (Eremin

& Guzhikov 1991 ).

The finst iwo sections arc composcd of clays,

aleurolites and sandstones with subordinate mari

and limestonc inrerJayers. The Gergebil Section

is represented by alternating terrigenous (clays,

sandstones) and carbonate (limestones) mem-

bers. The section near Nardaran consists of calca-

reous clays exclusivcly.

In the Central Cis-Caucasla (sections on the

Baksan and Urukh rivers), deposits of ail the

Hauterivian biozoncs occur, which is confirmcd

by ammonite index spccies (Egoyan & Tkachiik

1965). In Gergebil, only the uppei Hauterivian

substage is recognised from ammonite fauna

(Mordvilko 1960-1962). The underlying limc-

stone sequence according to macrotauna is refer-

red to the Hauterivian without further

subdivision, and the lowermost section, devoid

of organic remains, is referred to the Hauterivian

Stage conventionally.

The Hauterivian âge of the deposits near

Nardaran is bascd on microfaunal data (Aliev

1965).

In each of the sections studied, three subzones

were recognised; cwo of chiefly reverse (Rn) and

one of normal (N) polarities (Eremin &C

Guzhikov 1991) (Fig. 3).

In the palaeomagnecic columns of ail the four

sections through the Hauterivian, despite its

complexity, clear prédominance of reverse polari-

ty NRM is recorded (Fig. 4).

The Barrumian Sta(.;l'

The Barremian beds were studied on the Urukh

River, in the vicinity of Gergebil and Akusha

(North Caucasus) and on the Segiz-Yab River

(Central Kopetdag) (Fïg. 3> Appendices 4-7).

The Barremian from the North Caucasus is

represented by sandstones, aieuroliies and, to a

lesser extent, by clays. The Kopetdag Section

consists mainly of limestones and maris.

In ail the sections, both Barremian substage.s arc

recognised from the macrofaunal complex,

ammonites included (Druzchiz & Michailova

1960; Mordvilko 1960-1962; Anonymous

1985). In rhe section of the Urukh, the upper

Barremian deposits are condensed in a limestone

layer 0.5 m ihick.

The composite magnetostratîgraphic section of

ihc Barremian from the North Caucasus consists

of three major subzoncs: chose of reverse (R),

normal (N) and alternating (RN) polarities

(Fig. 3).

The palaeomagnetic column of the Kopetdag

Section consists of two major subzones: tfiose of

reverse (R) and alternating (RN) polarities

(Fig. 3, AppendLx 7), The luwer R-subzone cor-

icsponds to the lower half of the lower

Barremian substage. The RNbr subzone encom-

passes' the uppermost of rhe lower Barremian and

the upper substage. The analogues' of the North

Caucasian normal poJarity subzone arc mlssing

from rhe Segi/.-Yab Section due to the early

Barremian wash-oui, that has not been previous-

ly recognised in this région, but is clearly pro-

nounced in ihe adjacent Paroundag Range

(Ammaniyazov et al, 1987).

The lower An ian substage

The lower Aptian deposits were studied in four

sections: near the lown of Kislovodsk, in the vici¬

nity of Gergebil and Akusha (ail in the North

Caucasus) (Eremin 6c Guzhikov 1991) and on

the Segiz-Yab River (Kopetdag).

The lower Aptian in the North Caucasus is

represented by terrigenous rocks excJusively:

sandstones, aleurolites and clays. In the Segiz-Yab

Section, the lower Aptian consists mainly of aleu-

roliics with subordinate incerlayers of limestones,

maris and sandstones. In the Volga Région, the

lower Aptiat) structures arc composed chiefly of

clays and clayey sands,

The lower Aptian beds are saturated with ammo¬

nite fauna remains (Druzchiz 6c Michailova

I960; Mordvilko 1960-1962; Anonymous 1985;

Mosks'in 1986).

Only the lower Aptian Deshayesites weissi and

D. dâshayesi zones are palaeomagncdcally sam-

pled in the Caucasus.

On the .Segiz-Yab, the âges of ail ihc lower

Aptian beds, accuratc wirhin subscages, were sub-

stantiated by macrofauna (Ammaniyazov et ai

1987).

394

GEODIVERSITAS • 1999 • 21 (3)

Lower Cretaceous magnetostratigraphy in Caucasus

B

0)

c

O

NI

CO

êo

C

(D

C

CO

.to

c?

ce

I

Qi

üj

CD

C

O

N

n

D

CO

, T

üjernas

P. ponticus

Subzone

(magnetozone

Polarity

R3b

N2b

i

R2b

N1b

■

R1b

3

Synihei

Norlh

Caucasus

Berriasian slratotype section

Fig. 4. — Magnetostratigraphical corrélations of Berriasian deposits of North Caucasus (A) and between North Caucasus Région

and the Berriasian stratotype section (B). For lithology, see legend on Appendix 4.

GEOOIVERSITAS • 1999 • 21 (3)

395

Guzhikov A. Yu. & Eremin V. N.

Table 1 . — Corrélations of the Berriasian ammonite scales from stratotype régions and North Caucasus.

North Caucasus

after Druzchiz & Michailova 1960

Stratotype

North Caucasus

after palaeomagnetic data

Zone

Subzone

Zone

Subzone

(caipwneSides)

Zone

Subzône

Riasanites

Fauriefla

boissieri

Berriasefta

calfisto

Berriaseila

picteti

Riasanites

Fauneila

boissieri

rjasanensis

R. rjasanensis

s.str.

FaurieKa

boissieri

Calpionelliopsis

(zone D)

rjasanensis

R. rjasanensis

s.str

■IM

E euthymi

s.$tr.

Fiithyminera:^

Tirnovella

berriassensis

Malbosiceras

paramimoufjum

euthymi

Tirnovelia

berriassensis

BBB

Tintinnopsella

(zone C)

Dalmasiceras

daimasi

Dalmasiceras

daimasi

Tirnovella

Daîmastceras

daimasi

Rmovella

occitamca

T occitanica

Tirnovelia

occitanica

Berriaseila

privasensis

occitanica

s.str.

Tirnovella

occitanica

Calpioneila

Pseudosubplamites

ponticus

Pseudosubplamites

aranais

(zone B)

ponticus

In ail tlic exarained sections from rhe CauL-a^us

and the Kopetdag, the lowermost Aptian is dis-

tinguished for a reverse polarity magneiozone

(R^ap) (Fig. 3, Appendixes 4-8). rhLs magncio-

zone is srrarigraphically équivalent to the

D. weissi biozonc* and the lower parc of che

Deshayesites deshayesi.

It may be seen from the corrélation of the mate-

rials available (Fig. 3), that four reladvely large

zones of alcernaring, normal and chiefly reverse

polarities correspond lo rhe Lower Cretaceous

portion in che composite palaeomagnetic section

from the North Caucasus. The gap witbin rhe

Valanginian parc of magnetostratigraphic scale

(no Valanginian beds were sampled in the North

Caucasus) was climinated owing to palaeoma¬

gnetic snidies of the .sections from Mangy.shlak

and Azerbaijan) (Fig. 3). Their stratigraphie

ranges (stage, substage) correspond to the ortho-

zones Irom the general palaeomagnetic scale

(Anonymous 1992). Eaeh orthozonc is characte-

rised by a rather complicared structure owing to

subordinare sub- and microzones of opposite

polarities.

The Lower Cretaceous palaeomagnetic scale

opens with the altcrnating polarity orthozone

RNb-Vp embracing the Berriasian Stage and the

lowermost lower Valanginian substage.

The normal polaritj^ orthozone Nv^ characcerises

che uppermosi of the lower Valanginian and the

upper Valanginian subsrage.

The chietly reverse polarit)^ orthozone, Rnh-br,,

comprises the Hauierivian stage and che base of

che Barrcmian* The studies of rhe Hauterivian

reference sections from the North Caucasus,

liave, for the first time, rcvcalcd che correspon-

dence between the determined magnetozones

and the ammonite zones of general stratigraphie

scale.

The alrernating polarity orthozone RNbtj-apj is

strarigraphically équivalent to the uppermost of

che lower Barremian, upper Barremian and lower

Aptian.

COMPARISON OF THE REGIONAL AND

GLOBAL DATA ON THE LOWER

CRETACEOUS

The carrent ideas of che Lower Cretaceous

magnetic zonality are based upon the data on

linear magnetic anomalies, as well as upon fairly

numerous, but unequally informative data on the

Lower Cretaceous palaeomagnetism from various

régions ofEurasia.

In the known models of the Phanerozoic general

magnetostratigraphic scale (Khramov 1982;

396

GEODIVERSITAS • 1999 • 21 (3)

Lower Crecaceous magnecostratîgraphy in Caucasus

Stage

Substage

Zone

(ammonites)

Polarity

Valanginian

upper

Teschenites

callidiscLis

Himantoceras

tnnodosum

Saynoceras

verrucosum

lower

VTurmamiœfas

carrpyiotoxus

Vaianginianofthe

hypostratotype

of Angles

ai

0 )

U)

S

c5

D

CO

Aptian

ço

c

O)

c

ço

CD

Berria-

sian

>>

O)

O

Mt. Tyue-su

(Mangyshlak)

Stage

Zone

(nannofossils)

Polarity

C

CO

’c

’O)

T. verenae

c

CO

Stage

Zone

(calpionellids)

Polarity

Valanginian

Calpionellites

:

Calpionellcpsis

Cismon

(South Alps)

Fonte del Giordana

(South Alps)

Fig. 5. — Magnetostratigraphical corrélations between the Valanginian hypostratotype section of Angles (Besse et al. 1986),

Mangyshlak Région and South Alps Région (Bralower 1987; Cirilli étal. 1984). For lithology, see legend on Appendix 4.

Molostovsky & Khramov 1984), 3 ls well as in the

scalc by Harland et al. (1982), the Lower

Crctaceous is sharply ditfcrentiatcd Lato two

parts. The Neocomian belongs to rhe altcrnating

pülarity interval. whLle the Apti:m and the Albiati

stages correlatc with the cpoch of stable normal

polarity field. Thus, the boundary between two

major magnetostratones is established within the

base of the Aptian: between the NR-Gissar and

N-Djalal hypen:ones (Khramov 1982; Molo¬

stovsky & Khramov 1984).

The Berriasian Stage

The commonly accepted views upon the

Berriasian magneric zonality as an altcrnating

polarity interval, are bascd on research results

from varions continents [the stratotype section

from Southern France included (Galbrun 1985)]

and on the data from oceanic magnetometric

surveys (Fig. 3).

Fhc results of ihe présent srudy are in complété

accord with the ideas of sign-changing magnetic

zonality of the Berriasian, with slight R-polarity

prcvalence.

Analogues of the palaeomagnetic zones distingui-

shed by Galbrun (1985) in die Berriasian strato¬

type section (Fig. 4), are recognised the

sequences from the Caucasus, which has made il

possible to reveal the corrcladons -among ammo¬

nite scales h'om the t\s'o régions, and, moreover,

to record the approximate positions of calpLonel-

lid zones the Assa and Urukh sections.

'Fhe right side of Table 1 .show.s parallelizarion

results for the Berriasian palaeontologic uniis

from the scratotype and the North Caucasian

régions (the left side of the Table, corrélations

GEODIVERSITAS • 1999 • 21 (3)

397

Guzhikov A. Yu. & Eremin V. N.

among ammonite biozones and subzones, pre-

viously accepted by palaeontologists, are given

for comparison (Prozorovsky 1989).

The Vaiancïnian Siace

The Valanginian magnetic zonaliU' shows somc

problcm. Alternating polarity is recordcd in cbc

scale ot oceanic anomalies and in the North

Mediterranean sections. At the same time, the

data on the stage Angles bypostraroiype (Besse et

al. 1986) tesrify' to ihe normal polarity dominan¬

ce in the latc V'alanginian.

Comparisons ol the VaJanginian magneiosirati-

graphic sections Itom Mangyshiak, North

Mediterranean (Cirilli et al. 1984; Bralower

1987) and the Angles stxatotypc, hâve made It

possible, in the first place, to présent an explana-

tion for rhe reason ol discord among magnetos-

tratigraphic data on ihe Valaiiginian, and then tu

consider the interrelaiions among the ammonite

and calpionellid scalt*s of rhe stage.

In the South Alpine sections, provided with

microfaunal grounding, the Valanginian is cha-

racterised by alternating polarity (Fig. 5). In the

parastratütype and Mangyshiak sections, divided

according ro ammonites, an abitormal polarity

orthozone corre.spond.s lo the upper substage

(Fig. 5). An alrernaiing pt)lancy subzone (Fig. 5)

corresponds to the knver Valanginian sequence in

the Tyuyesu Mountains Section. Regretfiilly> the

lower Valanginian deposits from England were

not described in terms of magnetic polarity.

The above data coasidered, we may suppose the

deposits iVom ihc Calpioncllhes zone and from

the uppermosi of the Calpionelliopsh in Umbria,

to be analogous lo rhe lower Valanginian sub¬

stage. This inference is in agreement with Kent

& Gradstein (1985) data on corrélations between

the Valanginian calpionellid and ammonite zones.

In rhe scale of linear magnetic anomalies, rhe lar-

gest normal polariry clinm (MlON) is probably

analogoas to rhe Nv orrhozonc.

The Hauterivian S iage

The Hauterivian is characteriscd by sign-chan-

ging magnetic polarity.

The data on the Hauterivian palacomagnetic

structure in the Caucasus, is in accordance with

Harland et al. materials on linear magnetic ano-

I 398

malles /90/, with those by Pospelova &

Larionova (1971) from West Siberia, Ramazanov

(1987) and Ramazov &: Dedova (1980) from

lurkmenia, Pçchersky (1970) Irom nortii-east

Russia, Bralower (1987) from South Alps. In ail

the listcd régions, the Hauterivian palacomagne¬

tic columns show reverse over normal polarity

dominance, and record ar least eighr magnetic

field reversais (Fig. 3),

In the oceaniq scale (Harland et al. 1982), the

only major normal polarity chrori (M4) is regis-

tered in the middle of the Hauterivian interv;d of

the scale (Fig. 3)- In the composite rnagneto-

straügraphic section Irom the Caucasus, this may

bc analogous to the Nh subzone, associaied with

chc substage boundary.

Polarity distributions within rhe North Italian

Captiolü and Xausa sections, are a little bit diffe¬

rent Irom the above sketch, according lo

Cliannell tt al. (1979), normally magnetised

rocks obviousiy prevaÜ there (Fig. 3). This fact

bas not yet been unequivocally explained.

The Bakremian SïAt'.t

According lo ibe currem views, the Barremian

vSiage is characteriscd by complcx magnetic zona-

licy (Fig. 3).

Our resulis on alternating magnetic polariry of

the Barremian from the North Caucasus and

Kopetdag, are, on the whole, in good accord

with the data by I.owrie et al. (1980) and

Bralower (1987) on the South Alpine sections of

Umbria, Cismon, Gubbio, etc.» with the lower-

mosc of the srage corresponding to a probable

analogue of the Rbr subzone (Fig. 3).

At the same time, according co Channell et al.

(1987) définitions for the North Iralian sections

of Capriülo and Xausa major normal polarity

magnetozones correspond to rhe lowermost of

rhe Barremian Stage (Fig 3).

The comparisons ol the composite magneiostra-

tigraphic section from the North Caucjisus and

Kopetdag with Harland et al. (1982) scale, do

not deny corrélation of the Rbr subzone with the

M2 anomaly, or rhat of the RNbr subzone with

M1 and M l n chrons (Fig. 3).

The Aptian Stage

In ail the examined sections from the Caucasus,

GEODIVERSITAS • 1999 • 21 (3)

Lower Cretaceous magnetostratigraphy in Caucasus

Kopetdag and Volga Région, the lowermost of

the Apiian are distinguished fora reverse polarity

magnerü7.one, most probably analogous to the

MO chron of rhe anomaly scale (Harland et al.

1982) (Fig. 3).

CONCLUSION

Comparisons of the régional and global data on

the Berriasian-lower Aprian hâve shown the

results obtained ro accord in principle with the

magnelostraiigraphic matcrials known. The

results allow to hâve more précise ideas of the

Neocomian part o( the palacomagnetic scale.

In the stratigraphie aspect, the magnetozones

recognised are reliable stratigraphie bench marks

for synchronous corrélations of the deposits,

both on the régional and global scales.

Acknowledgements

The authors are grateful to Prof. Van der Zwan

(The Netherlands) for his helpflxl review on the

first draft of the paper.

REFERENCES

Aliev K, S. 1965. — Radiolarians from Loiver

Cretaceous beds of North~East Azerbaijan. AN

AzSSR publishing, Baku, 124 p. [in Russian].

/Vmmaniya/ov K. N., Sniirnova T. N., Dutalov V. L

et ai 1987. - Strarigraphy of Lower Cretaceous

beds ffom CenriuJ Kopetdag: 3-27 |in Russian], in

Geobgy of furkmemstan. Ylym, AJikhabad.

Anonymous 1985. — The Lourr Cretaceous in the

South of the USSR. Nauka, Moscow, 224 p. [in

Russian].

Anonymoiis 1992. — Stratigraphie Code. VSEGEI

Publication. Saint-Pererburg, 120 p. lin Russian].

Besse J., Boisseau L, Arnaud-Vanneau A., Arnaud

U., Mascle G. & Tlueuloy J. 1986. —

Sediment.iry modificarion.s, bannal rencwal and

magnetic sield polarity reversais in rhe VaUnginian

of the hypo.srratoiypc of Angles. Bulletin du centre

de Recherche Exploration-Production Elf Aquitaine

10(2) : 365-368.

Bogdanova T. N. 1983. — Valanginian of

Mangyshlak. Nauka, Moscow, 120 p. [in Russian].

Bralower T. ]. 1987- — Valanginian to Aprian calca-

reous nannofossil stratigraphy and corrélation with

rhe upper M-sequence magnetic anomalies. Marine

Mia'opalaeontology 11: 293-310.

Channeu J. E. 1'., Lovvrie W. & Medizza F. 1979. —

Middle itnd Early Cretaceous magnetic stratigraphy

from the Cismon secrion, Northern Ttaly. Earth

Planetary Sciences Letter (42): 153-166.

Channell J. E. T., Bralower T. J. àc Grandeso P.

1987. — Biostrattgraphy correlarion of Me.sozoic

polarity chron.s CMl to CM23 at Capriolo and

Xausa (Southein AJps, Iraly). Earth Planetary.

Sciences Letter {^Sy, 203-22L

Cirilli S., Marton P. & Vigli L. 1984. — TmpÜcationvS

of 3 tombincd biosiratigraphic and palaeomagnetic

srudy of rhe aumbrian Maiolica Formation. Earth

Planetary Sciences Letter (69): 203-214.

Druzehiz V. V. lèc JVIithailova 1. A. I960. — l.ower

Cretaceous Inostraiigraphy of Northern Caucasus.

Moscow Lfoiversity publishing, Moscow, 190 p. [in

Russian).

Egoyan V. L 5c Fkachuk G. A. 1965. — Stratigraphy

of Haucerivian of North Caucasus: 244-285 [iri

Russian], in Egoyan V. L. (ed.), Eaunu. stnttigrapby

and lithology of Mewzoiç and Cenozok beds frorrl the

Krasuffdarrégion. Ncdra, Leningrad.

Ercmin V. N. 1991. — Magnetostrjtigtaphy of ihe

Beiriasiân deposics of the North East Caucasus.

VIN'ITL N3725-B91. 10 p. fin Russian].

Eremin V. N. Gu/hikov A. Vu. 1991. — Results ol

magnctostnuigraphical rc.scarch of the Haucerivian

beds from Caucasus. V7A777, N154-B91, 11 p. [in

Russian].

— 1991. — Maguetostratigraphy of the Aptian beds

No.-rh-E3.sr Caucasus. KAV/77, N155-B91, 16 p.

[in Russian].

Galbrun B. 1985* — Magnetostratigraphy of ihe

Beniasian srraiotype .section (Berrias, France).

Earth Planetary Sciences Letter (74) : 130-136.

Glazunova A. E. 1973. — Palaeontology and stratigra-

phy of Cri'taceous deposits in the Volga Région: l.oiver

Cretaceous. Ncdra, Moscow, 324 p. (in Ru.s.sian].

Gri.shanov A. N. 1984. — Palaeomagnetic section of

C]reraceous deposits hom the right hank ot Volga

near Saratov city: 56-62 (in Russian], in Artemev

V. L, Bamlin G- L, Vosuyakov A V. et al. (cds),

Geohgical studies of the South Urals and Volga

région. SrraTigraphic and hihologic investigations.

Saratov IJnivcrsity, Saratov.

Guseyiiov A. N. 1988. — PaLteomagnetism of Jurassic

and Cretaceous deposits of the East 1 rans-CanCfisus.

IGANA, Baku, 19 p. [in Russian],

Harland W. B., CoxA. V.» Llewellyn P. G., Pickton

C. A. Smith A. G, Sc Walters R, 1982- ~ A

géologie time scale. Cambridge University Press,

Cambridge, England, 128 p.

Kent 13. V. &: (irad.srein F. M, 1985. — A

Crctacxious anil Jurassic gcochronology. Bulletin of

Gcoiagical Society of America 96: 1419-1427.

Khramov A. N. 1982. — Palaeomdgnetism. Nedra,

Leningrad, 312 p. [in Russian].

Lowrie W., Alvarez W., Silva L P. & Monechi S.

GEODIVERSITAS • 1999 • 21 (3)

399

Guzhikov A. Yu. & Eremin V. N.

1980. — Lower crctaceoas magnetic srratigraphy

in Umbrian pelagic carbonate rocks. Geophysical

Journal of Royal asUonomical Society 60: 263-281.

Lowrie W. & Channell J. E. T. 1983. — Magneto-

stratigraphy of the Juras.siC'Cretaceou.s boundary in

the Maiolica limestone (Unibria, Iraly). Geology

(12): 44-47.

Lowrie W.j Channell J. E. T. & Alvarez W. 1980. —

A revicw of magnetic stradgraphv investigations in

Cretaceous pelagic carbonate rodes. Journal of geo¬

physical research 85 (B7): 3597-3605.

Molostov.sky E. A. & Khramov A. N. 1984. —

Palaeomagnetic scale oF Phanerozoic and problems

of magnetostratigraphy. Transactions of XXVII

Înternaîioanl Geological Congress, Moscow, 1: 16-24

[in Russian].

Mordvilko T. A. 1960-1962. — Loiver Cretaceous of

Northern Caucasus and Precaucasus. Academy of

Sciences of USSR publishing, Moscow-Lcningrad,

T. 1, 240 p., T. 2, 296 p. [in Russian].

Moskvin M. M, 1986. — Stratigraphy of the USSR

The Cretaceous System, T. 1. Nedra, Moscow, 340 p.

[in Russian].

Pechersky D. M. 1970. — Palacomagnctism and

palaeomagnetic corrélation of Mesozoic deposits of

the North-East U.S.S.R. Reports of SVK NIC

Magadan 37: 58-99 |tn Ras-sianj.

Pospelova G. A. 1976. — Palaeomagnetic scale of

Jurassic and Lower Cretaceous time: 27-46 [in

Russian], in Palaeomagnetism of Mesozoic and

Cenozoic of Siheria and Far East. SO AN USSR,

Novosibirsk.

Pospelova G. A. & Larionova G. Ya. 1971. —

Palaeomagnetic zones of Hauterivian. Geology and

geophysics 8: 62-71 [in Russian].

Prozorovskv V. A. 1989. — Zones of Cretaceous System

in the USSR. Lower sériés. Nauka publishers

Leningrad Branch, Leningrad, 242 p. [in Russian].

Ramazanov S. A. 1987- — About the Régional

Magnetostratigraphy Scale of Jurassic and

Cretaceous of Turkménistan: 61, 62 [in Russian],

in Ammaniyazov A. (ed.). Géologie Science of

Turkménistan. Ylym, Ashkhabad.

Ramazanov S. A. & Dedova I. 1. 1990. —

Magnetostratigraphy of well 3 of the Egribogaz

field. Report of the Turkménistan Academy of

Sciences 5; 104-106 [in Russian].

Rzhev.sky Yu. S. 1968. — Investigations of rémanent

niagnetization of Lower Cretaceous oj Tadjikistan

dépréssion for solution of some questions of tectonics.

Leningrad, 27 p. [in Russian).

Sakliarov A. S. [976. — A key Berria.se stage section

of the North-East Caucasus. Proceeding of the

USSR Academy of Sciences, Sérié Geology 1: 38-46

[in Russian].

Tarduno J. A., Lowrie W., Slitcr W. V. et. al.

1992. — Reversed Polarity Characteristic

Magnetizarions in the Albian Contessa Section,

Umbrian Appennines, Ttaly: Implications for the

Existence of a Mid-Crecaceous Mixed Polarity

j nterval. Journal of geophysical research 97: 241 -271.

Treryak A. N., Vigilyanskaya L. l. &C Shcmpelcv A. G.

1976. — Palaeomagnetic section of Lower

Cretaceous of the North-West Caucasus: 33-42 [in

Russian], in Palaeomagnetism, magnethm, geoma-

gnetic field. Naukova dumka, Kiev.

Submitted for publication on 22 January 1997;

accepted on 27 September 1998.

400

GEODIVERSITAS • 1999 • 21 (3)

Guzhikov A. Yu. & Eremin V. N.

Kuli-Mejirskaya antecline

Gergebil antecline

Jn (NRM) - natural rémanent magnétisation

k - magnetic susceptibility

N, n - normal polarity Jn

R, r - reverse polarity

interval of normal polarity (N)

interval of reverse polarity (R)

absence of deposits or

absence of polarity data

ctays

sandstones

limestones

maris

aleurolites

absence of deposits

gap

I ^ I NRM vector projection

I-1 in the lower hemrsphere

I ~ I NRM vector projection

I———I in the upper hemisphere

~ I trend of rock remagnetisation

—-—I by the présent geomagnetic field

Appendix 4. — Palaeo- and petromagnetic characteristics of the Barremian-lower Aptian deposits from Gergebil Village.

404

GEODIVERSITAS • 1999 • 21 (3)

Lower Cretaceous magnetostratigraphy in Caucasus

Appendix 5. — Palaeo- and petromagnetic characteristics of the Barremian-lower Aptian deposits from Akusha Village. Same legend

as Appendix 4.

Appendjx 6. — Palaeo- and petromagnetic characteristics of the Barremian deposits from the Urukh River. Same legend as

Appendix 4.

GEODIVERSrîAS • 1999 • 21 (3)

405

Cretaceous sedimentary units of Mangyshiak

Peninsula (western Kazakhstan)

Ludmila F. KOPAEVICH, Alexander S. ALEKSEEV &

Evgenii Yu. BARABOSHKIN

Geological Faculty, Moscow State University,

Vorobievy Gory, 119899 Moscow (Russia)

barabosh@geol.msu.ru

Vladimir N. BENIAMOVSKII

Geological Institute Russian Academy of Sciences,

Pyzhevsky per., 7, Moscow 109017 (Russia)

ben@ginran.msk.su

Kopaevich L. F., Alekseev A. S., Baraboshkin E. Yu. & Beniamovskii V. N. 1999. —

Cretaceous sedimentary units of Mangyshiak Peninsula (western Kazakhstan), in

Crasquin-Soleau S. & De Wever P. (eds), Peri-Tethys: stratigraphie corrélations 3,

Geodiversitas 2^ (3) : 407-419.

KEYWORDS

Mangyshiak,

Kaz^oistan,

Cretaceous,

stratigraphy,

imconformity,

palaeobiogeography.

ABSTRACT

The Cretaceous succession of the Mangyshiak Région is reviewed. Two pe-

riods in the geological history of this région are recognised. Sedimentary

units are determined for period on the base of derailed stratigraphy. UsuaJly

the units are separated by unconformities, differing in range and significance.

The time of terrigenous sédimentation extends from the earliest Cretaceous

to the early Turonian, The Neocomian succession was lormed under chan-

ging Tethyan/Boreal influence. The main interruption in marine sedimenta-

tion took place in the early Hauterivian (which is probably missing in the

region)-Barremian interval, during which continental sédiments were deposi-

ted. Aptian to early Turonian deposits were formed within the European

Palaeobiogeographical Région with a few Boréal invasions. The time of car¬

bonate sédimentation in the “Chalk sea” Basin of the European

Palaeobiogcographic Région began in the late Turonian and continued

through the Maastrichtîan.

GEODIVERSITAS • 1999 • 21 (3)

407

Kopaevich L. F., Alekseev A. S., Baraboshkin E. Yu. & Beniamovskii V. N.

MOTS CLÉS

Man^'.shlak.

Kazaîuixraîi,

Crciacév

stratigraphie,

discordance,

paléobiogéographie.

RÉSUMÉ

Les unités sédinicnMires crétacées de la péninsule du Man^'shlak (Kazakhstan

occidental).

La série crétacée de la région du Mangyshlak est revue. Deux périodes dans

l’hisroire géologique de cette région sont reconnuCvS. Les unités sédimeniaires

sont déretminées sur la base d’une stratigraphie détaillée. Habicuellcmeni, les

unités sont scparée.s par des di.scordaiice.s, d’%e et de signification différents.

La sédimentation terrigène s’érend du Crétacé basal au Turonien inférieur.

La succes.sion du Néocomlen .s’est formée sous le changement d’influence

boréale-réthysienne. La principale interruption dans la sédimentation marine

a lieu dans rintervalle de I I lauterivien Inférieur (qui manque probablement

dans la régionj-Barrémien, durant lequel se déposent des sédiments conti¬

nentaux. Les dépôts de rAlbien-ruroiiieii înléricur se M»nr formés dans la

province palcobiogéographiquc européenne avec quelque.s inva.sions boréales.

La sédimentarion carbonatée du bassin de la » Mer de la craie ■) du bassin

paléobiogéographique européen débute au rutonien supérieur et se poursuit

pendant le Maastrichtien.

INTRODUCTION

This report includes biostratigraphic data

concerning Cretaceous high resolution stratigra-

phy of tlic Mangyslilak Mountains (Fig. 1). The

data werc collected diiring their field trips by

Naidin, Beniamovskii and Kopaevich (1980-

1986), and by Barabo.shkin (1989-1995). Thcy

were impicmented by data from the gcological

literature.

The stratigraphie data are based or correlatcd

with the standard biostratigraphical scheme for

western "BorcaJ’* turope, taken from recent

publications (Carter & Hart 1977; Robaszynslci

et al. 1982; Birkcliind et al. 1984; Wood et al.

1984; Robaszynski 1987; Schoenfeld 1990;

Rawson et ai 1996). We are not discussing

details and problcms of ihese stratigraphie corré¬

lations, which fall outside ihe scope of the pré¬

sent report.

STAGE BOUNDARIES

Investigation of palaeogeography and

sequence/evenc stratigraphy must be based on a

précisé and reliable zonal stratigraphical scheme

wirh preferably a wide corrélation potential. For

their investigations, rhe prevîous Russian authors

bave used the standard zonal scale for the Lower

Cretaceous (Luppov (?/. 1976, 1983, 1988;

Saveliev 1992; Baraboshkin 1992, 1996, 1997)

and for rhe Upper Cretaceous rhe stratigraphical

scheme of the Mangyshlak, where the loraniini-

fera zonal scheme is closely correlated wirh zonal

schemes based on macrofauna (Naidin et al.

1984a, K 1995).

Lower Cretaceous

The Lower Cretaceous of Mangy'shlak is charac-

terised by a terrigenous déposition In shallow

water ro near-shore and continental environ-

ments. The stratigraphy of the Lower Cretaceous

of Mangj^shlak is based mainly on ammonite dis¬

tribution (Fig. 2). It was mainly devcloped by

Semenov, Luppov, Sokolov, Saveliev, Bogdanova.

The biosrrarigraphic scale based on bivalves is

particularly iiseful and was devcloped by

Mordvilko, Nikiiina, Saveliev, Bogdanova. The

forarninifera scale resulis from research by

Myatlyuk and Vasilenko. Application of a fora-

minifera .scale is limitcd foi the Neocomian

because of stroiig faciès control, but is very useflil

for the Aptian-Albian interval.

408

GEODIVERSITAS • 1999 • 21 (3)

Cretaceous of Mangyshlak

Rg. 1. — Geological map of Mangyshlak.

The Jurassic/Cretaceous boundary coinddes with

a major unconformity. Berriasian sédiments are

represented by a shallow water sandy-silty succes¬

sion, with mari and limestonc intercalations, and

oysrer banks. Thcsedimems are irrcgularly disiri-

bured because of lacer érosion. The Jurassic/

Cretaceous boundary in Mangyshlak is determi-

ried by the appearance of ammonites of rhe

Tethyan family Berriasellidae: Riasamtcs Spath,

Neocosmoceras Blanchec, Subalpinitcs Mazenot,

etc. and of some représentatives of the Boréal

family Craspedltidae.- Siiritcs Sasonov (Luppov et

al. 1988). The bentbic assemblage aiso concains

U mixture of Boréal and Tethyan bitMives, gastro-

pod.s, bracliiopods and orher launa: Buchia voR

gensis (Lahusen), B. okensis (Pavlow), B, unci-

toîdes (Pavlow) (Boréal); Myophorella loewinsnn-

Icssingi (Rcnngartcn), Ruiitrigonia laevisrnla

(Lycett) (Tethyan) and others. It is interesting,

that foraminifera data demonstrate the absence

of Boréal éléments (Luppov et al. 1988). The

fauna indicates the presence ol the upper

Berriasian only and the absence of the Volgian to

middie Berriasian intcrval. The faunal assem¬

blage ÀUggesrs thar marine conditions disappea-

red near the Jurassic/Cretaceous boundat)^ and

after a short Tethyan traiisgres.sion, Boréal water

penetrated in the area.

The base of chc Valanginian is marked by an cro-

sional unconformity and by the presence of

phosphoritic conglomérâtes, h was recognised by

the appearancc of Boréal Valanginian ammonites

and buchiids. Valanginian sédiments were for-

med in shallow water environmcnt.s. Tlicy are

represented by various terrigenous faciès with

intercalations of carbonates. The Valanginian is

characcerised by tlic development of a Boréal

ammonite fauna: Nikltlnoceras Sokolov,

Polyptychites Pavlow, Dichotomites v. Koenen

(Luppov et ai 1983). There is the only évidence

lor die presence of Icthyan iauna is the upper

Valanginian ammonite Neohoploceras sp., figured

GEODIVERSITAS • 1999 • 21 (3)

409

Kopaevich L. F., Alekseev A. S., Baraboshkin E. Yu. & Beniamovskii V. N.

STAGE

SUBSTAGE

MEDITERRANEAN SCALE

(Hoedemaeker et al. 1995,

simplified)

MANGYSHLAK

(Saveliev et al. 1963: Saveliev 1992:

Luppov et aJ. 1983,1988; wrth changes

bv Baraboshkin, this paper)

ZONE, SUBZONE

ALBIAN

UPPER

Stoliczkaia

dispar

Stoliczkaia ($.) dispar

Pleurohaplites studeh

S. (F.) blancheti

Callihoplites \traconensis

Mortoniceras

inflatum

Mortonicems (Mortoriiceras) inl^tum

Senienovites (Semenovites) mtchaiskii

Semenovites (Planihoplites)

pseudocoelonodus

Semenovites (Semenovites)

tamalakensis

LOWER MIDDLE

Euhoplites lautus

Anahopittes rossicus

Hoplites (H.) perarmatus

Euhopiites loricatus

Daahestanites daphestanensis*

Anahoplites intermedius

Hoplites

dentatus

Hoplites spathi

Hoplites (H ) spathi

Lyelliceras lyelli

Lyelliceras (L.) lyellt

Douvilleiceras

mammitlatum

Pseudosonneratis (Isohcphtes} ecdeniaia'

Otûhoobtescxassus

Protohopfiies (H.) puzosianus

Sonneratia (Eosonnerafia) caperata

Sonneratia ttosonneratia) roluia

Sokplnvi^ subdraaunovt*

Sor)neraiia (Eosonneratia) scitda

Sanneratia fGlotx>snnneratia) perinHaa

Leymeriella

îardefurcata

Anadesmoceras stranaulatvm

Levmepeüa (Levrnetielia) aa^iœGtaîà'

ArcthopHtes (SubfOhvitites) protsjs"

A/cthoplites (Afcttioplitostpchrofnimsis

Leyrnerielia (Levmetiella) nkdiœstiTta’

APTIAN

UPP.

Mvpacanthopiites lacooi

M 1 S S 1 N G

AcanThohoptiies notant

Nolaniceras nolani

Acanthohoplites aschiltaensis

MID.

Parahopiites melchions

Parahopiites melchioris

^ictjeiomceras

sumodosocosfaiOm

i^icnetoniceras

suWoaosocostMim

LOWER

üufrertova turcafa

Dufrenova furcata

Deshavestîes aeshavesi

Deshavesites desha\,e5i

Deshayesites weisst

Deshayesites weissi

Deshavesites tuarkvricus

BARREMIAN

CONTINENTAL

FACIES

HAUTERIV.

ü_

Q.

3

_J

9

MISSING

VALNGINIAN

cr

LU

NeocomitesfTeschenites)

oaenmeranus '

Dichotomites bidichotomus

Saynoceras verrucosum

Œ.

Busnardoifes campylotoxus

Polyptychites polyptychus

Thurmanniceras pertransiens

Nikitinoceras hopliioides'

Thurmanniceras otopeta

BERRIASIAN

UPPER

Fauriella boissieri

Riasanites rjasanensls*

"Euthymiceras sp.

Transcaspiites transfigurabilis*

ci

Q

S

Tirnovella occitanica

MISSING

i

Berriasella jacobi

Fig. 2. — Ammonite zonation of Lower Cretaceous of Mangyshiak. Stars mark ammonite zones, revised or proposée! for the first time

in this paper.

410

GEODIVERSITAS * 1999 • 21 (3)

Cretaceous of Mangyshlak

from Mang\'.shlak by Gordccv {1971). The ben-

chic assemblage is rnixed and contains both

Boréal and Terhyan éléments, bivalves: Buchia

keyserlin^ (Lahusen), 5. sibirica (D. N. Sokoiov)

(Boréal), lotrigonia sca^iha (Agassi/), Litsch-

kovin'tgonia tcfnihuhenulata Saveliev; corals:

Thamnastvria digitata I-romeincI, Siereocoenia

colUrmria (Fronientel) (Tethyan).

The Vidanginian/Hauterivian boundar}'^ is very

difficult to reœgni.se in Mangyshlalc, and in the

whole Peri-Caspian Région. The lower

Hauterivian was traditionally described from

Mangyshlak according to Saveliev. He cited

records of Dichotoniites hïdkhuUnnus (kcynierie)

(Saveliev 1958; Saveliev & Vasilenko 1963).

According to up-co-date interprétation, this

ammonite should bc referred to the upper

Valanginian of mainly Boréal Province. Luppov

et al. (1983) referred shell-rich beds and sand-

stoncs to the Idautcrivian on the base of dïe pré¬

sents of the brachiopods Cyclùthym irregularis

(Pictec). C gillierani (Pictet) and of the corals

Actinostreâ cotliculosa Traulschold (in East

Karatau). The only record of the lower

Hauterivian Lyticocerus sp. us from the Peri-

Caspian Région (Koltypin 1970). We assume

that this idcmification was a erroneous, because

the inadéquate underscanding oi Lyticocerus

Hyatt, 1900 in the stratigraphie litcraturc of chat

time. If this were the câsc ihcn thcrc is no real

évidence for the existence of lower Hauterivian

sédiments in that area. The ochcr rcason for the

absence of lower Hauterivian in Mangyshlak is

the general palaeogeography. SedinientLS of chat

âge are missing over rnost of the Russian

Platform (In the north), in the norihern part of

the Scythian IMarform (to the wesr); in

Kazakhstan and Turkmenia (to chc south-cast)

rhey are présent mainly in continental faciès. In

the Tuarkyr area (situaied between the Great

Balkhan and Mangyshlak) the lower Hauterivian

is also missing. This is supported mainly by

oscracod data (Aleksceva et al. 1972).

The presence of upj)er Hauterivian in

Mangyshlak is can bc disctisscd, but is more

plausible, bccause .sédiments of that age cover the

eastern part ol the Russian Platform (including

the Peri-Caspian) and the Scythian Platform. It

is possible that part of the continental red-colou-

red unit (Barremian, according to tradicional

stratigraphy) belongs to chc upper Hauterivian as

was suppused by Saveliev & Vasilenko (1963).

The Haucerivian/Barremiuti boundary is noc

characterised by ammonites in Mangyshlak.

Usuallyin the Peri-Caspian area the boundary is

placed ar the disappearance of the upper

Hauterivian Boréal ammonites Simbirskitcs

Pavlow and Craspedx}dhcus Spath and the appea-

rance of the beleinnite Oxyteuthis Siolley. The

Barrernian age of red- and rainbow-coloured

sands, silts ând clays (Kugüscm Formation) is

supported by a spécifie foraminiferal assemblage:

Cyroldhwides sokolovae Mjatliuk and Conorbi-

nopsls hanemicus (Mjatliuk) by comparison witb

Peri-Caspian sections (Myatlyuk 1980) and by

ostracod data (KorockoV & Shilova 1982).

Sedinicnts of that type are widely distributed in

the 'iuranian Platform area. Ir was the time of

séparation from the Russian Platform Basin cnii-

sed by sca-level fil] and followed by the fresh-

ening of the water.

The Barremian/Aptian boundary is recognised

more easily in the région by the appearance of

rbe lower Apriaii ammonite Deshayesites

Kasansky. The ba.se of the Apdan coïncides witb

a régional transgressive surface and condensed

beds with Deshayesites deshayesi (Lcymcric in

d’Orbigny), A dechyl (Papp), Tropaeum sp. and

orher norrhern Tethyan fininal éléments (SavelicA'^

&: Vasilenko 1963). The Aptian succession is

reprcsenied by a sandstone-.sili.stone shallow

marine unit witb clays at the base, containing

niimerous sniall unconformiiies. The thrcc

Aptian substages are pre.sented in this area, but

the upper Aptian succession is condensed in rbe

basal phosphoric horizon of the lower Albian.

The ammonite assemblage kaown Irom

Mangyshlak {Deshayesites Kasansky, Parahoplites

Anthula. F.pichelaniceras Casey, Acanîbohoplites

Sinzow) demonstrates rbe influence of norrhern

Tethyan water.

The Aprian/Albian boundary is deflned ai ihc

base of Leyrneriella rardefutrata zone, which is

widely disrributed in the région. The Alhian suc¬

cession is formed by shallow-marinc and near-

shore terrigenous deposirs. Il was investigated in

detail (Saveliev 1973, 1992). Records of

Arcthoplites jachromensis (Nikitin) rogether with

GEODIVERSITAS • 1999 • 21 (3)

411

Kopaevich L. F., Alekseev A. S., Baraboshkin E. Yu. & Beniamovskii V. N.

leymeriellids (Saveliev 1*^73) arc very important

for characterising the short-ccrm influence ol

Boréal scas and rhis taxon is a good for correla-

ting Arctic and Tethyan scales (Baraboshkin

1992, 1996). The launal assemblage is very rich

in ammonites and contains mainly European

forms {Lcymcriella Spath. SoHnenitnt Bayle,

Otohoplitcs Steinmann, Hoplites Neiimayr,

CallihopUtes Spath, etc.). The Tethyan influence

is clearly visible in ihe lowêr Albian {Douvil’

leiceras Grossouvre abundance), lower middle

Albian (appearance of rare Lyellicems) and from

the middle iipper Albian onv^ards (where

Mortonlcerus Meek, Stoliczkaia Neumayr and

heteromurphs occur frequently). At tfic saine

time, an endémie évolution took place (the lower

upper Albian. wlien Semenaintes Clasunova was

widely distributed). The launal distribution indi-

cates a relative sea séparation. The Albian succes¬

sion is Very complote in terms of ammonite

stratigraphy (Saveliev 1992), but contains niime-

rous small stratigraphical gaps, marked usually

by phosphorites. The style of déposition during

the Albian changed from shallow open marine in

the beginning to near-shore in the end ty'pical for

Peri-Caspian (Baraboshkin 1996, 1997). The top

of the Albian is regionally eroded and some of

the Albian ammonites are found reworked, in

condensed basal phosphoritic horizon of lower

Cenomanian.

Upper CRi-iACEOiis

The Cenomanian/Turonian boundary is at the

top of dic Sciponocertis p'avilâ zone. The belcmni-

te Praeactinocamitx plenus (Blainvillc) is aiso cha-

racteristic for the terminal part of the Ceno¬

manian. The lower Turonian boundary position

practically corresponds to appearance ol the

Mytiloides inoceramid I incage and this level is an

event which can bc iraced throughout the

Tethyan and Borcal rcalms.

The Turonian/Coniacian boundary coincides

with the First appearance of (Zremnoceramus

Yotundütm {%emu Tfôgcr non Ficgc; Kauftman et

al. 1996). This level is lower than the firsc

Cremnonrantus deformis (Meek), which was men-

tioned in previous Russîaii scheme.s.

The Coniaciaii/Santonian boundary coincides

with the base of the Cladoceramus undulatoplica-

tiis zone. It is a very good level, hecause the

remains of this taxon is very easily identified,

1 he Santonian/Campanian boundary is at the

base of the Goniotenthh granidaui tjiuidnua zone

Ln Avestern “Borcal” Europe. This level coincides

almost exactiy with the disappcarance of

MarsiiPites testudinariîis {Sch 1 othcim) in

Mangyshlak as elsewhcre. Zonal species of

belcmnites not been lound here. Gonioteuthis

Bayle species do noi extern to the easr beynnd

the Donecs Basin. Assemblages of other belem-

nites, Aitinoaimdx latvigatus Arkhangelsky,

détermine the âge ol this Interval as early

Campanian (Naidin et 1984b).

The Campaniau/Maastrichrian boundar)'^ is very

sharp: mass fîndings ol Belemnitella langei

Jelerzky group are suddeuly teplaced by mass fin-

dings of Belemnella.

The Maastrichvian/Danian boundary is very

sharp aIso, because a stratigraphical gap is présent

and shown by the disappcarance of many macro-

fauna) groups: ammonites, belentnices, inocera-

mids.

The micropalaeontological scheme for the Upper

Creiaceous of Mangyshlak is very derailed and

contains 26 foraminiferal subdivisions (Fig. 3).

The identification of zones is based on rracing

species assemblages. At different time intervals

the représentatives of different généra took a lea-

ding stratigraphie signrficance: Gavelinella

Brotzen for the Cenomanian/Turonian, Sten-

sioeina Broizen for ilie Couiacian-Saruonian,

Botiinnoides Cushman for the Campanian/

Maastrichtian.

The corn mon occurrences of Gavelinella cenoma-

nica (Broizen) and Rotalipora appeninnka (Renz)

arc relcrred to the lower C^cnomaniaii, and

appcar.mce ol Lingolagavelinellti glohasa (Brotzen)

is rclatcd to the middlc-upper txnomanian.

The lower Ilironian inten'al ofioniminifera évo¬

lution is marked by the présence of large

Hedbergella Broennimann & Brown and Whitei-

nella Pessagno (zone à Grandes Globigcrincs »),

whilc the middle-uppcr Turonian interval is

determined by appearance and évolution of

Margsnotruncana sp. and Gavelinella monilifor-

mis (Reuss).

l'he abundaiice of Mitrginotruncima Hofker or

“Grandes Rosalines” increases ncar the Turonian-

412

GEODIVERSITAS • 1999 • 21 (3)

Crecaceous of Mangyshlak

Coniacian boundary deposits. This boundary is

determined by the mass appearance of

Gaveli ne Ha p raei nfrasa n ton ica ( M j a 1 1 i u k )

(- G. afF, vombensis). Remsella kelleri Vassilenko

and also by small Stemioeina. Mass occurrence of

rypical Stensioehui gramdata granulata ( Olbcrtz) >

GaveVmella thalmanni (Brotzen)> G, imnbemis

(Brorzen) (= G. infrasantônica). Osmgtdatia ivhi-

tei whitei (Broizen) are à lypical for the upper

Coniacian. Stemioeina excalpui exculpta (Reuss)

appcars in the terminal part of the Coniacian

and is cspccially numerous in the lower San-

tonian.

The Santonian/Campanian boundary is conside-

red to be wirhin the Bolivinoides strigillatus zone.

The appearance and mass occurrence of

Stensioeina pommerana Brotzen, Gawliyiella cle-

mentianii clemtntiana (d’Orbigny), Bolivinoides

decoratus (Joncs) are typical for the lower

Campanian, thosc oi Brotzenella monterelemis

(Marie) for the middie Campaniaiv The upper

Campanian is determined by the appearance of

Cihicidoides voltzianus (d’Orbigny) followed

by Bolivinoides draco miliaris Hütermann &c

Koch, Bolivina kalifiini (Vassilenko) (= B. menu-

sata (Reuss), narrow spécimens), upwards by

Brotzeîiella taylorensis (Carsey) and in the most

terminal part by Angulogavelinella gracHis

(Marsson).

The Campanian/Maascrichtian boundarv'^ is deter¬

mined on the basis of the appearance of

Ncoflahellina rettculata (Reuss) and Bolivina decur-

rens (Ehrenbetg), but also on the présence of

A^vmàdim AngulogaveltnclLt gracîlis (Marsson). The

middie part oi the lowet Maastrichdan is ditferen-

tiared by Brotzenella compLinata (Reuss) and the

upper part by Bolivinoides draco draco (Marsson)

and Anonialinoides subcarinatus (Cushman &

Deaderick). The upper Maasrrichtian is characte-

rised by the appearance of Brotzenella praeacuta

(Vassilenko) and of Anonialinoides pinguis

(Jennigs) and in ics terminal part by the of occur¬

rence of Hanzmma ekblomi (Brotzen) and of

Pseiidatextiilana elegans (Rzehak).

This stratigraphical schemc allows corrélation of

ail Upper Cretaceous sections in Mangyshiak

wirh chose of many areas of western part of

"Boréal" Europe; Anglo-Paris Basin, western

Germany and lowland part of Poland.

GEODIVERSITAS • 1999 • 21 (3)

THE SUCCESSION OF SEDIMENTARY

UNITS

‘‘Sedimentary units” stand for relatively confor-

mable succession of genetically related strata

bounded at the top and base by utteonformities

or by corrélative conformities. 'Phis is a modifica¬

tion of an earlier usage by Sloss (1976), There

are many dilferent visible and invisible gaps and

unconfurmities in the investigated area (Savcliev

1971; Naidin 1987; Naidin & Kopacvich 1988).

LoWHR CrF.TACROUS SF.DIMEIsriARV ÜNITS

The Lower Cretaceous succession contains many

different stratigraphical gaps and several large

unconformiries- Mosily they are erosional in ori-

gin because of shallow conditions of the whole

succession. The main gaps and flooding surfaces,

which separarc different sedimencary unies, could

be determined in the following leveis (Fig. 3).

The lower Berriasian; a gap appeared during

significant palaeogeographical rebuiîding and

interrupting of sédimentation. Hencc, an uncon-

formity is visible at the base of che upper

Berriasian (it overlies different parts of the

Mesozoic or Palaeozoic sequence). There are

many small gaps inside the Berriasian interval

which are only of local signifiçance.

The gap and unconformity berween the upper

Berriasian and lower Valanginian extend over 1-

2 ammonite zones. Usually, this Icvel is marked

by erosional surface with phospliorîtcs. Also typi-

cai for Mangyshiak is that the lower Valanginian

overlays the Middie Jurassic, and highly conden-

sed phosphoric horizons were deposited. The

highest condensation is seen in the Nikitinoceras

hoplitoules zone, but the base of the Valanginian

(-an analogue of the Neotollia klimovskiensis zone

ofSiberia) is missing.

In the Valanginian-Barrcmian interva] a hiatus

includes the complété lower Hauterivian. The

gap is usually indicated by a tbin b.isal level with

phûsphorites, softground and an ero.sional surfa¬

ce development. The existence and complereness

of other parts of rhe Hauterivian/Barremian suc¬

cession is under discussion and needs additional

palaeotuological evidence.

The Barremian/Aptian boundary hiatus extends

over 1-3 ammonite zones. It is represented by a

413 I

Kopaevich L. F., Alekseev A. S., Baraboshkin E. Yu. & Beniamovskii V. N.

Symbol

Zone

Hamawaia ekblomi, Anomalinoides pinguis, Gavelinella ex gr. danica, Pseudotexîularia varians, P. ele-

gans

XXVI

Brotzenella praeacuta, Cibiddes kurganicus, Gavelinella perfusa, Tappanina selmensis

XXV

Bolivinoides draca draco, Colelfes crispas. Gavelinella rnidwayensis. Sfensioeina caucasica

XXIV

m,2

Brotzenella comptanata. Spjrvplectawmina suiuraiis. Gaveltneila weilen. Anomalinoides suùcarinatus,

Bolivtna incrassata incrassata, B. incrassata crassa

XXIII

Angutogavelinella graciUs stellaria, Neoflabelitna reticuiata. Osangulans nava^oana, Gyroidina globo-

53. Cibicfdpides bernbw. Bolivina decurens, Bolivinoides deticafulus. B. petersscmi, Reussella minuta

XXII

cPa"

Brotzenella (aylorensis. Neoflabeilina praereliculata, Bolivina incrassala incrassata, Pseudouvigerina

chstata, Bolivinoides giganievs

XXI

cPa^

Bolivinoides draca miliêris. Bponides frankei, E conspectus, Gavelinella cayexi mangyshiakensis,

Bolivina kalininl. Gemellides ordnus, Rugagfobigerina rugosa

XX

cPa’

Cibicidoides voiUianus Heterostomella foveofata, Plectina ruthenica, Globoratalites emdyensis,

Gavelinella clementiana laevigata. Globolrvncana worozovae

XIX

CP2

Brotzenella monterelensis, B. rrrenneri, Gavelinella clementiana usakensis, Arenobulimina convexoca-

merata, HelerostomeHa praefoveolata, Orbignyna sacheri. 0. ovata, Voloshinovella tertia. V. laffitei

XVIII

cPi"(up)

Cibicidoides aktüiagayenais, Ptectha convergeas

XVII

CPi3(|oWj

Cibicidoides temirensis. C. montanus. Eponides biconvexus. Bolivinoides laevigalus laevigatus.

Boiiviniteffa galeata

XVI

CPi2

Bolivinoides decoratus decoratus, B. granulatus, Osanguiaria cordienana, Globigerinelloides volutus

XV

cp,'

Gavetineila clementiana clementiana, G. dalnae Neoflabellina nigosa, Stensioeina pommerana,

Reussella pseudospinulosa. Bolivinoides laevigalus finitima. Globotruncana area

XIV

sVcp,*

Bolivinoides strigillatus, Ataxophragmium orbignynaefonmis, Gavefinella stelligera, Globotruncana arca-

formis

XIII

Stj

Osanguiaria whttei potycamerats. O. whitei crassa, 0. wnîtei wnitei. GaveJtnetla ex gr. stelligera.

Cibiddes excavatus

XII

St,

Stensioeina granulata perfecta. S. granulata incondita, S. exsculpta gracflis

XI

cnj-st,

Stensioeina exsculpta exsculpta, Gavelinella vombensis, G. umbilicatula, Cibicidoides enksdalensis

X

CRa

Stensioeina granulata granulata. Spiropieciammina embaensis. Valvulineria iaevis. Gyroidina turgida,

Qlûborotaktes rnicheiinianus. Osanguiaria whitei whitei. Gavelinella vcmbensis{=^ G. infiasantonica),

G. Ihalmanni, G. costulata. Bolivinjta eleyi

IX

cni

Reuasella kelleri, Gavelinella praeinfrasantonica, Gavelinella kellerl, G. costulata, Stensioeina granulata

kelleri. Margmotruncana coronala

VIII

Ataxophragmium nautiloides. Gavelinella ex gr. costulata, Cibicidoides praeeriksdalensis,

Marginotruncana æmi

VII

«2

Gavelinella monitiformis, G ammonoides. Spiroplectammina praeionga Gaudryina vahabUis,

GloborotaiitQS mulUsephts, Reussella carinata. Marginotruncana iapparenli, M. marginata, Hedbergella

agalarovae

VI

ti(up)

Cloborotalites hançensis. Spiroplectammina cunenta. Gaudryina subserrata, Gyroidina nitlda.

Valvulineria leniicula. Gavelinella vesca. Cibicidoides apprima

a

ti(IOW)

Hedbergella hoUli, H. portsdownensis. WhiteinoHa bdttonensis, W archeocretacea, W baltica,

Giobigennelfoldes oentonensis

IV

cm2.3

Ungulogavelinella globosa.Brotzenella berthelini. Gavelinella vesca

■■

cm^

Gavelinalla cenomanica, G. baltica. Ungulogavelinella orbiculata. Cibiddes polyrraphes polyrraphes,

Neobulimina numerosa, Hedbergella caspia, Thalmanninella appenninica

Fig. 3. — Foraminifera zonation of Upper Cretaceous of Mangyshiak.

414

GEODIVERSITAS • 1999 • 21 (3)

Cretaceous of Mangyshlak

condcnsed horizon containing small phosphatic

pcbbles with reworked lower Aptian fauna.

The Aptian/Albian boiindary gap including the

iipper Aptian-ba.sal lowcr Albian (2-3 ammonite

zones to the wholc middlc-upper Aptian and basal

Albian). It is an important unconlormity marked

by a strong erosional and environmentaJ brcalc.

Traces of upper Aprian are recognisable in rewa-

shed phosphatic pebbics in Mangyshlak sections.

There is an unconformity in the toprnnst Albian

(usually less than one ammonite zone, but in

some Mangyshlak sections - hall of the stage is

missing). A gap séparâtes Lower and Upper

Cretaceous sequences. It is easily recognisable by

a thick pliosphoritic horizon and by an uncon-

tormity at uhe base. Ail hiatuscs are more extensi¬

ve in easterly direction in che marginal parts ol

the basin. Because of the gaps mentioned above,

the following sequences were recognised in the

Lower Cretaceous of Mangyshlak.

Upper Berria.sian-Valanginian unir (T): rhe unir is

separated by a very strong unconformity at the

base of che upper Berriasian and by an erosional

surface at the top of che V^ilanginian. It is a very

complex member with many small gaps, especial-

ly in the lower Valanginian part. I his unit begins

with coarse-grained near-shore sédiments and

fmishes with rclativcly deep-water clayey sédi¬

ments for ibe latesi stage of scquence develop¬

ment. It is important that the unit was formed

mainly under Boréal waier influence with shori-

lerm peneiraiiori of Tethyan water at its begin-

ning.

Upper Haurerivian (r)-Barremian unit (II): the

unit includes mainly subaeral sédiments. There is

an erosional surface ai ihe base of ihe scquence

and another erosional surface at iis top.

Apcian unit (111): rhe unir scarcs at the transgres¬

sive part of the lowcr Aptian with an erosional

surface and an unconformity at its base. The

upper limic of unit HT is an erosional surface

with the condcnsed upper part ol ihc Aptian

stage. This unit was formed during a tran.sgressive-

regressive cycle, finished during the late Aptian

in near-shore ta subaeral (partially) environ-

ments. The deepest condirions followed by an

anoxie event exisred during the latesi early-mid-

dle Aptian. The déposition took place under

Tethyan water influence.

Albian unit (IV) is characterLsed by a rapid trans'

gression and a slow late early to latest Albian

shallowing. It is separated by an erosional surface

front che Aptian. At the top. there is a strong

unconformity with erosional surface and plios-

phoric condensation overlain bv the Ceno-

manian. Unit IV is represenced by a trans-

gre.ssive-rcgres.sive cycle with a change of condi¬

tions ai the end of the carly AJbian-bcginning ol

the middlc Albian. During this rime, rhe sandy

to .silty-claycy shallow marine .sédimentation

changed into a near-shore environment. The

Albian development of Mangyshlak Basin was

affcctcd by Borcal influence at ihc beginning, by

séparation front oihet basins in the early lare

Albian and by an increased influenec of Tethyan

waters in the late.st Albian.

Ul'l'F.R Crftackoüs sedimentary units

Six ■sedimenrar)’^ units compose the succession of

the Upper Cretaceous in Mangyshlak (Fig. 4).

Units I-II are differenriated from those with ter-

rigenoLis composition: sands. sandstones and

clays. Units IIl-VI contain carbonate clays, maris

and chalk. There are “black beds” on ilic

Cenomanian/Turonian boundary in the siraii-

graphically complété sections.

There i.s only ont* régional unconformity in the

Upper Cretaceous .succession of Mangyshlak

area: ar the Cenomanian/Turonian boundary,

but rclacively complète sections aiso exisr. Many

small hiaiu.ses .similar to hard grounds are visible

in the carbojvaie pan ol ail sections of

MangysWak (Naidin & Kopaevich 1988). The

genesis of ihe.se hardground.s is explained by a

combincd effcct of climatic and cusracic agents.

It is suggested iliai carbonate rocks containing

hardgrounds are a modification of rhythmically

bedded strata.

The clay intercalations or “clays” differ from the

carbonate sédiments above and below in rhe

abrupt dccrcasc in the CaCO^ amounr. It is assu-

med that the "clays’’ resuit from submarinc carly

carbonate biogcochemical dissolution at the sca

floor caused by an abrupt increase in biological

produciivily of the pciagic zone (Naidin 6c

Kopaevich 1988).

The Upper Cretaceous interval in Mangyshlak

can be divided in six units. These units and their

GEODIVERSITAS • 19&9 • 21 (3)

415

Kopaevich L. F., Alekseev A. S., Baraboshkin E. Yu. & Beniamovskii V. N.

Fig. 4. — Sedimentary units of lhe Cretaceous of Mangyshiak. 1. clayey sands: 2. clays, siltstone and sandstone alternations;

3. sands, siltstone and sandstone alternations; 4. soft sandstones; 5, clayey siltstones; 6. sandy maris; 7. clayey maris; 8. maris;

9, dolomitised maris; 10. marls-sandy mari alternations; 11. clayey dolomites: 12. dolomites; 13, llmeslones; 14, carbonated clays;

15. main stratigraphical unconformities; 16. cross-bedding; 17. bioturbation; 18. conglomérâtes; 19, phosphoric nodules and pebbles

{phosphorite horizon); 20. erosional surface; 21. hardground. Roman numerals agréé with sedimentary units.

416

GEODIVERSITAS • 1999 • 21 (3)

Cretaceous of Mangyshlak

boundaries were formed vmder the influence of

sea-level changes, but some of them hâve a tecto-

nic origin.

Unit I (Cenomanian-lower Turonian): the

rcmain.s of oystcrs, other bivalves and phosphatic

nuclei of ammonites are usually présent. The

foraminifera zones I-IÎI characterise this séquen¬

ce. This unit contains a very pour assemblage of

benthic foraminifera, but the Cenomanian/

Turonian boundary inrerval is characterised hy

large Hedbergella-Whiteinella planktonic forami¬

nifera associarion.

Unir 11 (middle-upper Turonian-lower Conia-

cian) lias a hiaru-s in its base. îts sue is different

in diflerent parts of the area - sometimes a part

of the Cenomanian or ail of the middle-upper

Cenomanian and the lower part of the lower

Turonian arc missing. Thcrc i.s a phosphatic hori¬

zon at the base of unit II. This Ls a condenscd

section, which was formed partly under the

influetice of sea-level changes (Hancock 1992).

The beginning of this unit may coincide with

mark 89.8 Ma in the curve of shorc onlap of

Haq et al. (1987) (Naidin 1995). Inoceramids,

brachiopod.s, rare ammonites and echinids are

présent. The foraminifera zones lY-VIII charac-

terisc this succession. Bcnthic/planktonic forami¬

nifera ratio is aiways high. but decreases near

Turonian/Coniacian boundary ("Grandes

Rosalines” intcrval).

Unit tll (upper Coniacian-Santonian) was for¬

med duriiig an unstable custatic situation. There

is a sharp hardground surface at the base of this

unit. Traces of eustatic transgression arc visible

towards the end of thLs unit, its beginning raay

coincide with mark 85 Ma of rhe main curve of

Haq et al. (1987). This is rhe "Marsupites trans¬

gression'’ in Western Europe and in Mangyshlak.

Remains of inoceramids and erînoids are usually

pre.sent hcre. The foraminifera zones IX-XIII

characterise these units. Bcnthic/planktonic fora¬

minifera ratio is also high.

The boundary of units 111 and IV (or Santonian-

Campanian boundary) shows a small condensa¬

tion at this level. Belemnite rostra are abundant

and remains of inoceramids are rare inside rhis

unit (Lower Campanian). Many small echinids

{Offaster Desor, Galeola Klein) are found in the

lower part of this unit. The upper part is charac-

GEODIVERSITAS • 1999 • 21 (3)

terised by belemnite.s, rare ammonites and abtm-

danc small and large echinids also. Very rich

assemblage of foraminifera is présent, benthic

foraminifera prevatl. The beginning of Unir V

(middlc Campanian) coincides with mark

77-5 Ma. The eustatic rise of sea-lcvel took place

at this time and tlie transgression peak prohably

coincide with mark 7.3.5 Ma of Hancock (1992)

(Naidin 1995).

Unit VI consi.sts of chaJk of Maastrichiiari âge in

Mangyshlak. The lower boundary of this unit is

different in different places; a continuous transi¬

tion or a small or big hiatus in the Southern

Aktau Mountains. The upper Maastrichtian part

of the unit bas a régressive character with short

transgressive impulse towards the end. so callcd

'^elegans transgrcssioïC (mark 67.5 or 68.5 Ma:

Wicher 1953). The bcnthic/planktonic foramini¬

fera ratio decreases sharply at this level. This Late

Maastrichtian short but intensive transgression is

clearly reA^ealcd by scdimeniological and structu¬

ral properties and was also shown by the last out-

burst in the appearancc of new globotruncanid

taxa (Maslakova 1978). Many different fossil

remains exist tn this unit: bclemnitcs, ammo¬

nites, oviters-, braclTiopods, echinids. The top ol

unit VI coincides with the eustatic fall of the sea-

level at the Maastrichrian/Danian boundary. The

biological crisis is fixed at this boundary, al!

remain.s ot ammonites, belemnites, inoceramids

and practically ail planktonic foraminifera disap-

peared. Ail the sections show a hiatus in the base

ot the Danian. only two Mangyshlak sections

(Koshak and Kj^lsai) arc marked by “boundary

clay” with iridium in this intcrval.

CONCIUSION

From the data presented, the following stages in

rhe development of Mangyshlak during the

Cretaceous can be recognised.

K A time of terrigenous sedimenration:

- sédimentation in a basin with longitudinal

connections with strong boréal influence and

smaller Tethyan invasions: upper Berriasian-

Valanginian;

— sédimentation in continental conditions: upper

(?) Hauterivian-Barremian;

417 I

Kopaevich L. F., Alekseev A. S., Baraboshkin E. Yu. & Beniamovskii V. N.

- sédimentation in a basin wich longitudinal to

latitudinal connections, with Tethyan influence:

Aptian;

- sédimentation in a basin longitudinal to latitu-

dinaJ, but prcdominanrly latitudinal connections

with shon Borcal and Tethyan incursions and

with partial basin isolation: Albian;

- sédimentation in a laritudinal-oriented basin of

European Palaeobiogcographic Région:

Cenomanian-carly Turonian.

2. A pcriod of carbonate sédimentation in the

“Chalk sea” Basin of European Palaeo-

biogeographic Région: middle Turonian-

Maastrichtian.

Acknowledgein en ts

The authors are grateful to Prof. W. Kuhnt

(Universiry Kiel, Germany) and Prof.

E Robas'/ynsky (haculté Polytechnique de Mons,

Belgium) for constructive comments on the

manuscript. The work was undertaken with the

support of Peri-Tethys Program.

REFERENCES

Alekseeva L. B., Korotkov V. A. 6c Shilova D. D.

1972. — On the age of Ky/.ylkyr Formation of

Tuarkyr (West Turkmenia): 41-45 [in Russian], in

Mesozoic bwstrangraf>hy ofotl- and gas-fieUs of the

USSR, Nauka, Moscow,

Baraboshkin E. J. 1992, — The Lower Albian of

Central parts of the Russian Piarform: 20-36, (jn

Russian], />/ Shik S. M. (ed.), The Phanerozokstra-

tigraphy of the centra! piirt of the East-European

Platjorm. Centrgeologia. Moscovv.

— 1996. — Russian Platform as a controller of the

Albian Ttthyan/Borcal ammonite migration.

Geolùgivii Cafp(Hhn'it A7 (5): l-IO.

— 1997. — The Tcthyan/Borcal Problem as the

resuit ol puliicobiogcographical change.s: Early

Cretueeous exauiplcs froni the Russian Platform.

MinercfHit Siovara 29 (4-5): 250-,15?.

Beniamovskii V. N, Kopaevich I .. F. 1997. — Late

Santonian-Maastrichtian benthic foraminiferal

zonation in the Europe;in palaeobiogcographical

area (EPA). Mtneralia Slovacn 29 (4-5): 328-330.

Birkelund T., Hancock J. M., Hart M. B., Rawson

P. F., Remanc J., Roba.szyaski F., Schmid F. &

Surlyk F. 1984. — Cretaceous stage boundaries-

proposais. Bulletin of the Geological Society of

Denmark^^: 3-20.

Gordeev N. (. 1971. — On the ammonites froin the

Polyptycintcs horizon of Neocomian of Mangyshiak.

Transactiom InsttHite Geology and Geophy^ics 2:

190-198 [in Rus.sian].

Hancock ). M. 1992. —Transatlantk corrélations in

the Campanian Maascrichdaii stages by cusratic

changes of sea-level. Geological Society of London,

Spécial Publier non s 70; 241-256.

Haq B. U., H.irdenbol |. & Vail P. 1987. —

Chronolûgv of the flucruaung sea JeveJ sinct the

Triassic. Sfience 235 (4/93): 1 ! 56-1167.

Kauffman E. G., Kennedy W. J. & Wood C. J.

1996. — l’hc Coiiiacian Stage and Substage boun-

darie.s, m Rawson P. F., Dhondt A. V., Hancock

J. M, 6c Kennedy W-J, (ed-s). Second Iiuernationai

Symposium on Cretaceous Stage Boundaries,

Bnissels 8-16 ,September 1995, Bulletin de l'Institut

Rnyal des Sciences mjturelles de Belgique, Scierurs de

la Terre 66 :31 -43*

Kolt)'pin S. N. 1970. — Cretaceous. Peri-Caspian

dépréssion, />r Geulogy of USSR, Ncdra, Moscow

12: 544-596 [in Russian].

Korotkov V. A. & Shilova D. D. 1982. — On the

problem of the âge of Kuguseni Formaiiou of

Mangyshiak: 36-39 fin Russian), in Benttenson

V, A. (ed.), Sp’Utigtaphy andpalaeoçeopâphy ofoiT

and gas~ftt'ld reg/oni of the yonng pLztfmm. Kauka,

Moscow.

Luppov N. P., Alekseeva L. V., Bogdanova T. N.,

K<irûtkov V. A., Dzhalllov M. R., Lobacheva S. V.,

Kuzmicheva E. F, Akopian V. T. 6c Smimova .S. B.

1983. — Yalangiuuin of Mangyshlah. Nauka,

Moscow, 120 p. [in Russian).

Luppov N, P., Bogdanova T. N.. Lobacheva S, V.,

Akopyan V. T, DzhalÜov M. R., Korotkov V, A.,

Myatlyuk E. V. & Poretskaya L. S. 1988. —

Beniasian of Mangyshiak. Nauka. Leningrad. 240 p.

[in Russian).

Maslakova N. 1. 1978. — Glohotruncumds of Southern

part of USSR. Nauka, Moscow, 166 p. [in Russian].

Myarlvuk L. V. 1980. — On the imporrauce of

Foraminifera from the epicruttituntai basin of

Russian Platform for the élaboration of a zonal

scheme for the Barremian. Prohlems of Micro-

palaeontology 2y. 12‘’'-138 [m Russian).

Natdin D. P. 1987. — The “Hardgrounds” in epi-

conrinciiral carbonate sections of Upper

Cretaceous: 242-262 [in Russian], in Milanovsky

E. £. 6c Dobruskina I. .A. feds). Hbtorical Geology:

results and perspectives. Moscow State Universiry,

Mo.scow,

— 1995. — Eutitasy at Epicontinetiial Seas of East-

European Phulorm. 2- [.ate Cretaceous Plarfonn

sequences. Biylititien Moskovskogo Obchestva

îsphatelei Prirody. Otdcl Geologu 70 (5): 49-65 [in

Ru.ssian].

Naidin D. P., Beniamov-skii V. N. tk. Kopaevich L. F.

1984a. — Methods of studying transgression and

régression cycles (examplified by West Kazakhstan sec-

418

GEODIVÊRSITAS • 1999 • 21 (3)

Cretaceous of Mangyshiak

tions). Moscow State University, Moscow, 162 p.

[in Russian].

— 1984b. — Biosrraiigraphic classification on the

Upper Cretaceous of the European Palaeo-

biogeographic Région. Vestnik Moskovskogo Univer-

sitetUy seryageolo^a 39 (5): 3-15 [in Russian].

— 1993. — Palaeogeographical base for stratigraphical

subdivisions. Moscow State University» Moscow,

136 p. [in Russian].

Naidin D. P. & Kopaevich L. F. 1988. —

Synsedimentary gaps in Upper Cretaceous of

Mangyshiak. Moscow State University, Moscow,

128 p. [in Russian].

Rawson P. F., Dhondt A. V., Hancock J. M. &

Kennedy W. J. 1996. — Proceedings of Second

International Symposium on Cretaceous Stage

Boundaries, Brussels 8-16 September 1995.

Bulletin de llnstitut Royal des Sciences Naturelles de

Belgique^ Sciences de la Terre (>(y : 1-123.

Saveliev A. A. 1958. — The Lower Cretaceous

Trigoniidae of Mangyshiak and Western

Turkmenia. Trudy Vsesojuznogo Nauchno-

Issledovatelskogo Geologo-Razvedocïmogo înstituta

125: 1-515 [in Russian].

— 1971. — On stratigraphical unconformines in the

Lower Cretaceous of Mangyshiak. Biyllutien

Moskovskogo Obchestva Ispitatelei Prirody. Otdel

Geologii 46 (2): 68-72 [in Russian].

— 1973. — Lower Albian srratigraphy and ammo¬

nites of the Mangyshiak (Leymeriella tardefurcata

and Leymeriella regularis Zones). Trudy Vse-

sojîiznogo Nauchno-Issledovatelskogo Geologo-

Razvedochnogo Instituta 323: 1-340 |in Russian].

— 1992. — Lower Albian ammonites of Mangyshiak,

their phylogeny and importance for Albian zonal

stratigraphy of South of the USSR {Cleoniceras

mangyschlakense Superzone). Nedra, Saint

Petersburg, 223 p. [in Russian].

Saveliev A. A., Vasilenko V. P. 1963. — The faunistic

basis ol the Lower Cretaceous stratigraphy of

Mangyshiak. Trudy Vsesojuznogo Nauchno-

Issledovatelskogo Geologo-Razvedochnogo Instituta

218: 248-300 [in Russian].

Schoenfeld J. 1990. — Zur Stratigraphie und Okolo-

gie benthischer Foraminiferen im Schreibkreide-

Richtprofil von Lâgerdorf/Holstein. Geologisches

Jahrbuchy Hannover, A 117: 1-139.

Sloss L. L. 1976, — Areas and volumes of cratonic

sédiments, Western North America and Eastern

Europe. GeologyA (5): 272-276.

Wicher C. A. 1953. — Micropalaontologishe

Beobachtungen in der hôheren borealen Ober-

kreide, besonders im Maastricht. Geologisches

Jahrbuch 1-26.

Submitted for publication on 22 April 1997;

accepted on 30 June 1998.

GEODIVERSITAS • 1999 • 21 (3)

419

Configuration of the Palaeogene deposits

of Southern Russia

Eleonora P. RADIONOVA, Irina E. KHOKHLOVA & Tatiana V. ORESHKINA

Geological Institute, Russian Academy of Sciences.

Pyzhevsky per. 7, Moscow. 109017 (Russia)

khokhlova® ginran.msk.su

oreshkina@ginran.msk.su

Radionova E. P., Khokhlova I. E. & Oreshkina T. V. 1999. — Configuration of the

Palaeogene deposits of Southern Russia. in Crasquin-Soleau S. & De Wever P. (eds), Peri-

Tethys: stratigraphie corrélations 3. Geodiversitas 21 (3) : 421*428.

KEYWORDS

Palaeogene,

microplankton,

srratigraphy,

paJaeogeography.

ABSTRACT

Tectonic and custaric history of the Ea.st European Plate strongly influenced

the accumulation of Palaeogene sédiments. Due to thèse factors, lower part

of Palaeogene deposits is disrrihuted in an elongated area with an axis

stretches N-S, and the upper strata in an area that extends E-W.

Micropalaeontological investigation of diversified Palaeogene lithofacies allo-

wed U.S to subdivide and correlare Palacocene and middle Eocene sédiments

of the East European (Russian) Plate and to propose the picture of its évolu¬

tion during the Palaeocene-middle Eocene time.

MOTS CLÉS

Paléogène,

microplancton,

stratigraphie,

paléogéügraphic.

RÉSUMÉ

Configuration des dépôts paléogènes de la Russie méridionale.

L'histoire tectonique et eu.statique de la plaque est-européenne a profondé¬

ment influencé l’accumulation des dépôts paléogènes. En relation avec ces

deux facteurs, la partie inférieure des dépôts du Paléogène est répartie sur une

aire allongée de direction N-S, et la partie supérieure avec une direction E-

W. Les recherches micropaléontologique.s sur différents lirhofaciès du

Paléogène nous permettent de diviser et de corréler les sédiments du

Paléocène et de PÉocène moyen de la plaque est-européenne (russe) et de

proposer une image de son évolution durant le Paléocène-Éocène moyen.

GEODIVERSITAS • 1999 • 21 (3)

421

Radionova E. P., Khokhlova I. E. & Oreshkina T. V.

INTRODUCTION

Within ihe Ru.ssian Plate, Palaeogenc deposits

are classed into rwo lithologie types — Ukrainian

and Volgian - differing essentially in lithology

and stratigraphie range. Ukrainian-lype sections

are found to lhe west, and Volgian-iype deposits,

to the east of rhe Ulyaitovsk-Saratov zone

(Leonov 1964).

The Palaeogene deposits display an E-W zona¬

tion. As far north as the latitude of Volgograd,

Palaeogenc deposits are reptesented by ail the

sériés and show lithologie similariry to carbonate

terrigenous, North Caucasus-type sections. Tn

more northerly areas, Palaeogene sections are

incomplète and are dorninated by ^iliteous-

terrigenous faciès. The bonndary of the area

occupied by the Southern, Caucasian faciès coin-

cides witlî che junction zone between chc south

flank of the Easi Eiiropean craion and the posc-

Hercynian Sc^thian Plate.

The Figure I shows tcctonic structure of ihc

Southern part of ihc Russian Plate. The divcrsity

of Palaeogene lithologie associations is largcly

determined by the rcctonic complcxity of ihc

study area, locutcd in the junction zone. The

North Doncts thrust (Fig. I: A) separating rhe

Easr European craton and ihe Scythian Plate

remained active throughoui Cainozoic rime. The

Southern slope of the platform i.s adjoined by

Precambrian structures; the Ukrainian shield

(Fig. 1: A) and the Voronezh upJifc (Fig. 1; B)

with the Dnieper-Donets atilacogcn (Fig. 1; C)

in-between, and by the Peri-Caspian Basin

(Fig. 1: D) The Karpinsky swell (Fig. 1; E) is an

E-W-trending marginal structure of the post-

Hercynian Scythian Place. This swell gives way

wesrward to the orogenic Palaeozoic structure of

the Doners area (Fig. 1; F), a constituent part of

the Dnieper-Donecs aulacogen (Milanovsky

1987).

The Ukrainian dépréssion, filled by Ukrainian-

type Palaeogenc deposits, is a Meso-Cainozoic

dépréssion (Fig. 1: I) overprinring the south

flank of the Voronezh Massif of lhe Dnieper-

Donets graben, and, partiy, of the Ukrainian

shield.

The N-S-crending Ulyanovsk-Saralov dépression

(Fig. 1: II), to which the Volgian-type Palaeogene

deposits are confined, is related with an inversion

ot vertical movements. This dépréssion evoivcd

in Lite Crctaceous-Palaeocene time, and since

the Eocene it has been involved in the N-S-

trending uplifring zone, presenily known as the

Volgian uplift. Although lhe Ukrainian and

Ulyanov.sk-vSaraiov dépréssions occur closely in

spacc, their Palaeogene infilLs differ esscnrially in

structure, stratigraphie range, and lithologie

type. The zone that separating ihese areas

extends N-S along rhe East Ergeny swel! (Fig. I:

4) to E)on-Mcdveditsa swell and Kirovsk swell,

and is likely to reflecr a deep mantle structure

that trends roughly N-S.

Throughout the Palaeogene domain, lhe lower

beds are distributtd in an elongated area whose

axis .stretches N-S from Ulyanovsk to Volgograd,

and the upper .strata gravicate lo an area that

extends E-W from Kiev to Volgograd. The.srruc-

rural rearrangemenr respunsible for this réorien¬

tation took place in the early to early-middie

Eocene.

OBJECTIVES OF STUDY

The diversiry of Palaeogenc lithtifacies throu-

ghoiit this alUimportani area renders their strati¬

graphie subdivision and corrélation rather

difficult. Despiie the long histor)' ol ihc studics,

the rnicropaJacontologital coverage of these

deposits rcmains incomplète and non-unilorm.

This rclers primarily to rhe stratigraphy that is

based on .siÜceous microfossil.s, which abound in

the Palaeocene deposits of Volgian-typc sections

and in the Eocene strata of Ukrainian-rype sec-

cion.s.

First, this .study sets oui to constrain the strati¬

graphie range of Palaeogene siliccous faciès in the

Ulya novsk-Saratov dépression.

Second, our aim is to impiovc the understanding

ol the structure and age of the Eocene depo.sits in

rhe arc-a where the Dnieper-Donets depre.ssion

adjoin.s the Peri-Caspian Basin, and where the

Eocene strata comprise boih carbonate and sili-

ceous faciès, pcrniittinga corrélation of northerly

(cratonic-type) and North Caucasian sections.

Sections and boreholcs penetrating the

Palaeogene deposits we hâve studied are shown

422

GEODIVERSITAS • 1999 • 21 (3)

Configuration of the Palaeogene deposits of Southern Russia

2-km contour of basement surface

Faults

ED Cristalline basement

|A a] Oceanic crust

O Meso-Cainozoic cover

Fig. 1- — Schemfi showing main lectonic slruclures of the southetn part o1 Russian pJartorm, after Geodynarnic map ol the USSR

and adjacent seas (Anonymous 1988> and Milanovsky (1987). Boreholes and sections: 1, Slariy Saltov. 2. Varuga. 3. Strelech'e;

4, Kanlemirovka; 5, Sergeevka; 6, Rudaevka, 7. Boguchar; a, Veshenskoe, 9, Uzen; 10. Smishlyaevskaya Gorka; 11, Vodoratsky

Quarry; 12. Sengeley. Precambrian structures of the Russian Plate: A, Ukratnian shield; B. Voronezh uplifl; C, Dnieper-Donets aula-

cogen; D, Peri-Caspian Basin; E, Pachelma trough: <- a, northern Donets (hrusl. Posl-Hercynian structures of the Scythian Plate;

F, Karpinsky swell: G, Donets folded area- Meso-Cainozoic structures: I, Ukralnian synecline, II, Peri-Caspian Basin,

III, Ulyanovsk-Saratov synecline. Cainozoic méridional structures: b, East Ergeninsky swell (horst); c, Don-Medveditsa swell

{modem Volgian uplift); d. Klrovsk swell.

GEODIVERSITAS • 1999 * 21 (3)

423

Radionova E. P., Khokhlova I. E. & Oreshkina T. V.

in Figure l. Thèse are lype sections in two areas

that are crucial to Palaeogene stratigraphy in the

central Ulyanuvsk-Sararov dépréssion (Sengelcy

Smyshiyacvskayâ Corka, Kuroedovskie Vyselki

quarry, and Vodoratsky quarry sections) and

along ihe NE flank of the ükrainian dépréssion

(246 Stary Saltov. 230 Strelechie, 5-93 Boguchar,

and 9540 Riidacvka holcs and Yaruga, Sergeevka,

and Kantemirovka sections).

STRATIGRAPHIC SUMMARY OF

PALAEOCENE DEPOSITS (VOLGIAN-TYPE

PALAEOGENE STRATA)

Vblgian-type Palacogene deposits (Leonov 1964)

hâve a siliccous-terrigenous composition and

show a distinct cycliciry. It is cusromarily bclie-

ved that in this région PaJaeogene deposits hâve a

complété stratigrapfiic range and pass conti-

nuousiy into lower Eocene strata.

The Palacocenc deposits are subdividcd into chc

Syzran, Saratov (= Kamyshin), and Tsaritsyn for¬

mations. The last is assigned to uppermost

Palaeoccnc-lowermost Eocene. However, sections

in the lowcr and uppet rcaches of the Volga are

difFicuIt to corrclatc. The Syzran Formation is a

rather diverse and intricatcly built complex of

clay-siliceous and sand sédiments as thkk as 150-

180 m, grading Into eacb orher larerally from

area to area. In the lower reaches ol the VbJga,

the lithologie division into chc lower (clay-gaize)

and upper (sand) member is quitc consistent. In

the middie reaches of die Volga, the formation in

places becomes tripartkc, wich a .sandy middie

member, airhough in places the formation

consiscs almo.st entirely of diatomite and gai^e

[gaze (= opoka) biogenic krypeogene siliceous

sedimenr witli clayey adinixture]. The Saratov

(= Upper Saratov, Kamyshin) Formation is often

bipartite (wirh the lowcr member consisting of

gaize, and the upper. of sand), its thickness iiot

exceeding 20-30 m. In the Volga’s lower reaches,

the base of this' formation contains a distinct

intercalation of lobacco-coloured sapropcl-like

clay.

The sandy Tsaritsyn Formation in the Volga’s

lower reaches is clearly rhychmîc and consîsrs of

sandy gaize and sandstone. In the Volga middie

reaches, this formation ovcrlaps crosionally the

Linderlying deposits, is made up of thin sand

stone with occasional leaf casts, and thickens to

40-60 m.

The lithologie uniformity and cyclicit); the cor¬

rélation ol faunal rernains with particular litho-

fâcies, the cotnmunly poor préservation of

siliceous plankton due lo diageueiic transforma¬

tion of organlc opal, ail handicap ihc stratigra¬

phie subdivision of Palaeocene deposits.

Stratigraphie range of the lithostratigraphic units

(formations) is highly dispurable. In this study,

the paper by Khokhlova de Oreshkina (this volu¬

me) sets OUI to dcfinc raorc prccisely the strati¬

graphie range of Palaeocene deposits in the

Volga’s middie reaches.

STRATIGRAPHIC SUMMARY OF EOCENE

DEPOSITS (UKRAINIAN-TYPE

PAIAEOGENE STRATA)

The Dnieper Basin displays : ( 1) a reduccd stiati-

graphie range and Umited distribution of the

lowcr Eocene strata: (2) a chiefly sandy composi¬

tion of ail the horizons except two: “Kiev”

Horizon represented by a clay-marl member with

glauconite, and the lowcr part of the “Kharkov”

Horizon, which shows diatomite intercalations

in the clay-sand member.

The corrélation of stratigraphie unies of the

Dnicpci-Doncts Palacogene strata largely

dépends on rhe dating of the “Kiev" and

'^Kharkov” beds. Initially, the “Kharkov'" sand-

stones were correlated with the Latiorfian ones

bascd on mollusks (Sokolov 1903). On these

grounds. the “Kharkov” Member was as.signed to

the Oligocène, and the “Kiev” Member, to the

upper Eocene. I«arer, “Kiev” was moved into the

middie Eocene, and “Kharkov”, into the upper

Eocene (Makarenko et al. 1987). Tn some works,

especially in tliose dcaling with rectonics, this

view persisrs still. However, after the Kiev

Formation yielded the middie Eocene forarnini-

fera assentblage of the Cïlaborotalia wmndhmtrgi-

naia zone (Grigyalis et al. 1988), the

stratigraphie range of rhe “Kiev” and posc-“Kjev”

strata in ihc stratotype area (Dnieper Basin near

Kiev) became a subject of révision, and new

424

GEODIVERSiTAS • 1999 • 21 (3)

Configuration of the Palaeogene deposits of Southern Russia

h 56*

\- 54'

J- 52-

h 50’

U 48-

46’

E3 Depositional edge

Sandstone, sand

I— I Shale, clay

Mari

I I— 1 1 Diatomaceous deposits

@ Boreholes and sections

Fig. 2. — Upper Palaeocene (Thanetian) palaeogeographic scheme.

variants of their corrélation with more northerly

and eascerly areas began to appear.

rhis corrélation, howc\'er, is rcstrained by the fàct

chat Eocene deposits change in lithology toward

the northeast parts of the Ukrainian dépréssion,

where the chiefly carbonate strata in the correlates

of the Kiev Formation become replaced by clay-

sand deposits. In that area, anothcr litho-strati-

graphic scheme is used (Sokolov 1965).

As it was shown above, to subdividc the western-

GEODIVERSITAS • 1999 • 21 (3)

425

Radionova E. P., Khokhlova I. E. & OreshkinaT. V.

Denositional edae

l'^7"i| Diatomaceous deposits

1 ^-| shale. clav

hrS l ümestone

1 *• • • 1 Sandstone. sand

1“^! Anoxir. organin shalfi and rlay

l'X^I Mari

® Boreholes and sections

Fig. 3. — Middie Eocene (Bartonian) palaeogeographic scheme.

most section that we hâve studied (Boguchar),

which is locared in the Volga-Don interfluve, the

lithostratigraphic scheme from the North

Caucasus can be applied (Kurlaev & Akhlestina

1988).

In this area, the correlates of the Kuma Forma-

426

GEODIVERSITAS • 1999 • 21 (3)

Configuration of the Palaeogene deposits of Southern Russia

tion are recognised, with Bartonian anoxie evenrs

associated in eastern Pcri-’lcthys. The issues of

stratigraphie range and faciès changes in rhe

Eocene deposits of the eastern flank of the

Ukrainian dépression are addressed in tfie paper

of Khokhlova et ai (rhis volume).

PALAEOGEOGRAPHY

The Figures 2 and 3 présent palacogeographic

maps showing distribution of Paiaeocene (upper

Thanetian) and middle Eocene (Bartonian)

depo.sit.s for the Southern part of the former

USSR.

In lare Paiaeocene time, che Volga Région and

Peri-Caucasian basins formed a single, shallow-

water, highly productive marine basin wiih sili-

ccoLis sedimentarion (Fig. 1). Distanov (1964)

proposcd rhat Paiaeocene sédiments of the

Middle Volga Région accumulared in a large guif

of an inland sea. with an intense iipwelling pro-

cess. The diatomites may hâve accuniulated in

marginal parts of palaeodeltas. Another view-

point is that there exis’ted seawày(s) between the

Volga and West Siberian basins. Tins is suggesied

by the sîmilarity of the faunas and floras. For

example, the West Siberian assemblage consisrs

of 100 diacom species (Anonymous 1974) More

than 80% species are corn mon with those of the

Middle Volga palacobasin.

Tfie Middle Volga Région sagged mainly in the

biosilicâ accumulation. Pure diatomitc.s near the

town of Sengiley contain abundant radiolarian

assemblages of Buryellc^ tetradica Foreman,

Tripodisàflus sengHensis Koziova and régional

zones establishcd by Koziova (1984) and related

to rhe late Paiaeocene. In the northern Peri-

Caspian Basin, upper Paiaeocene rich radiola-

riaiis comjïlex accompanied by nannoplankton

of NP8 zone are présent. In Cis-Caucasia, rhis

Icvel conclatcs to the Goryachy Klyuch and

Abaza formations that contain abundant yet

poorly preserved radiolarian assemblages. The

entire basin had idcnticaJ radiolarian assem¬

blages, although the assemblages of the BtiryelLi

tetradica Foreman and Petalospyrîs foveolata

Ehrenberg, in the Middle Volga sections contain

a significant mimber of widespread tropical spe¬

cies.

In early Eocene time, the gulf (or scaway) that

existed on the site of che middle and partly, lower

reaches of the Volga, disappeared. Marine envi¬

ronment gâve way to continental, which pcrsis-

ted in the Middle Volgâ Région imo Eocene and

Oligocène times. In the Dnieper-Donecs Basin,

lower and lower-middle Eocene siraca coiisisi of

alternating lerrigenou.s nearshorc marine and

continental faciès. The marine basin survived

only in the south — on the site of the Peri-

Caspian Basin and Cis-Caucasia.

A new vast transgression was confined to the

upper Luieiian-Bartonian. The outlinc of rhe

basin, however, changed signifîcantly (Fig. 3). In

latc Lutetian time, carbonate-terrigenous strata

of the Kiev Formation were widespread in the

Dnieper-Donets dépréssion. The “Greenish Kiev

Marlsume'" bas long been correlatcd with che

glauconite-rich maris and limescones of rhe

Kere.sta Formation in Cis-Caucasia, which

contain siinilar forani and nannofossil assem¬

blages. The Bartonian strâtà differ signifîcantly

l>eiwecn the Southern and norchcJ-n parts of the

basin. Along the neg-th and south inai^ins of che

Dnieper-Donets Basin and along the north mar-

gin of the Peri-Caspian Basin, widespread are

deposits enriched in organic silica, whereas in the

central part of the basin carbonate-clay sédi¬

ments of the Kuma Formation, partly or cndrcly

anoxie, were laid down. In the Vblga-Don inter-

fluVe, siliceous faciès giving way ro rhe Kuma

faciès were attribuced to the existence of the

Millerovo seaway berween the Donets basemenr

high and rhe ea.st slope of ihe Voronezh Basin

(Leonov 1964).

The paiaeogeography of the South Russia Basin

with hio.siliceous accumulation changed drasti-

cally from N-S at the time of the Selandian-

lower Thanetian transgression ro W-E during the

Lutetian-Bartonian transgression.

Acknowledgements

The authors are very gratefui to Prof D. Lazarus

(Berlin, Germany) and Prof. K. Nigrini

(Canmore, Canada) for their careful reading and

their help in the rewriting of the paper.

GEODIVERSITAS • 1999 • 21 (3)

427

Radionova E. P., Khokhlova I. E. & Oreshkina T. V.

REFERENCES

Anonymous 1974. — Diatoms of the USSR. Fossils

and Recent. Volume 1. Nauka, Leningrad, 403 p.

[in Russian].

Anonymous 1988. — Geodynamic Map ofthe USSR

and Adjacent Seas. Seule 1: 2 500 000^ Zonenshain

L. P., Mezhelovsky N, V. & Natapov L. M, (eds).

Minisrry of Geology of the USSR.

Distanov LI. G. 1964. — Paleoeene deposites,

Trudy Kazanskogo filiala AN SSSR, séria geologia

11:46-62.

Grigyalis A. V., Zosimovicch V. Yu., Burlak A. F.,

Ivannik M. M., Kraeva E. Ya. & Lulyeva C. A.

1988. — New data on the stratigraphy and paleo-

geography of the Palaeogene deposits of the west

part ot the European USSR. Soviet Geology 12: 41-

54 [in Russian].

Kurlaev V. I. & Akhlestina E. F. 1988. — The

Palaeogene of the Middle and Lower Volga Région.

Saratov Universlty Publication, Saratov, 203 p. [in

Russian].

Leonov G. P. 1964. — The Main Problems of Palaeo¬

gene Stratigraphy ofthe Russian Plate. Moscow State

University Publication, Moscow, 552 p. [in

Russian].

Makarenko D. E., Gorbunov V. S., Ivannik M. M.,

Masiun N. V,, Stotland A. B. & Blan M. Ya.

1987. — Stratigraphie Scheme for Palaeogene

Deposits of Ukraine. Naukova Dumka Publication,

Kiev, 114 p. [in Russian].

Milanovsky E. E. 1987. — Geology ofthe USSR.

Part 1. Moscow State University Publication,

Moscow, 4l4 p. [in Russian].

Semenov V, P. 1965. — Palaeogene of the Voronezh

Anteclise. Voronezh University Publication,

Voronezh, 279 p. [in Russian].

Sokolov N. A. 1903. — Lower Tertiar)' Deposits of

Russia. Trudy Geology Komiteta 10 (2) [in Russian].

Submittedforpublication on 22 April 1997;

accepted on 30 June 1998.

428

GEODIVERSITAS • 1999 • 21 (3)

Early Palaeogene siliceous microfossils

of the Middie Volga Région: stratigraphy

and palaeogeography

Irina E. KHOKHLOVA & Tatiana V. ORESHKINA

Geological Institute, Russian Academy of Sciences,

Pyzhevsky per. 7, Moscow, 109017 (Russie)

khokhlova@ginran.msk.su

oreshkina@ginran.msk.su

Khokhlova I. E. & Oreshkina T. V. 1999. — Early Palaeogene siliceous microfossils of the

Middie Volga Région: stratigraphy and palaeogeography, in Crasquin-Soleau S. & De

Wever P. (eds), Peri-Tethys: stratigraphie corrélations 3, Geodiversitas 21 (3) : 429-451.

ICEYWORDS

Palaeogene,

bioÿiratigraphy,

raoiolaria,

silicoflaeellates,

oiatoms,

Middie Volga,

East European Platform.

ABSTRACT

The Sengiley section (Middie Volga Région» Russia) provides one of the

most complété late l’alaeocene sedimentary sequence wirh well-preser\^ed dîa-

toms, silicoflagellates, and radiolarians. I hree zones of régional zonal scheme

(Kozlova 1994) based on radiolaria werc distinguished In the sédiments:

Buryella tetradicUy Tripodiscinus sengilensis^ Petatospyris foneolam zones. Based

on diatom régional scheme (Strelnikova 1992) Trinacrtii venîriculosa and

Hemiaiilus periptertis zones were recognised. Aithough assemblages of siii-

ceous microfossils strongly differ front the oceanic coeval associations, the

précisé âge of the boréal zones was determined on the basis of direct corréla¬

tion wich standard zonal scales of diatoms, silicoflagellates and radiolarians.

For example, from sédiments of Petalospyris foveoUita zone, severai spccies

described by Nishimura (1992) from ihe upper part of the Bekoma campe-

chemis standard radiolarian zone of the North-West Atlantic were found and

allowed us to corrclate thèse rwo zones. Two zones of the standard oceanic

diatom scheme (Bai ron ik Baldauf 1993) {Hem/aulus peripterus and

Hemianlus incurvus zones) and standard silicofiagellate Maviculopsis constricta

zone w'ere distinguished in the Sengiley section, Siliceous-terrigenous

Palaeogene sédiments of the Middie Volga can be considered as rypical sédi¬

ments of the marginal epicontinenial bavSÎn. Siliceous assemblages of the

Sengiley section are ver)' close to assemblages from Lulinvorr and Serov for¬

mations of the West Siberia and the eastern Unils slope, Fur Formation and

Sambian Formation of North-Easc Europe» aithough the geometry of

connections berween these basins during late Palaeocene is siill not ciear.

GEODIVERSITAS • 1999 • 21 (3)

429

Khokhlova I. E. &C Oreshkina T. V.

RÉSUMÉ

Microfossiles silicetix paléogènes de la région de Li moyenne Volga : stratigraphie

et paléoécobgie.

La coupe de Sengiley (région de la moyenne Volga, Russie) présente une des

séquences scdirnentaires les plus complètes du Paléocène supérieur avec des

diatomées, radiolaires, silicoflagellés bien con,servé.s. Trois zones de la zona¬

tion régionale (Koziova 1994). fondée sur les radiolaires, sont distinguées

dans Ica sédiments ■* zones à Bitryclla tettadica^ Tripodheinus sengHensis,

Petalospyris fbveolata. Dans l.a zotration régionale à diatomées (Srrelnikova

1992), les zones à Trinacria mnrtadosa and Hetniaulns peripicriis sont recon¬

nues. Bien que les assemblages à microfossîles siliceux dilïèrent fortemenr des

équivalents océaniques, Tige précis des zones boréales a éré déterminé sur la

base de corrélation.s directes avec les échelle.s régionales standard a diatomées,

silicoflagellés et radiolaires. Par exemple, pour les sédiments de la zone

Petalospyris joveolata, plusieurs espèces décrites par Nishimura (1992) dans la

partie supérieure de la zone sc-andard à radiolaires à Bekotna campechensis du

Nord Ouest de l'Atlantique ont été trouvées et nous permettent de corréler

ces zones. Deux zones de la zonation océanique standard à diatomées (Barron

&: Baldâuf 199^) (zones à Hemiimlus peripterus and IJemiaulus im'unms) et la

zone standard à silicoflagcllés à Naviculops'ts constricta ont été trouvées dans la

coupe de Scngiley. Le.s sédiments paléogènes siliceux-terrigènes de la moyen¬

ne Volga peuvent être considérés comme typiques de bassin marginaux épi-

continenraux. Les assemblages siliceux de la coupe de Sengiley sont très

proche.s des assemblages des formations de Lulinvorr et Serov de Sibérie occi¬

dentale et du versant est de l’Oural, des formations de Fur et Sambian du

Nord Est de FEurope, bien que la géométrie des connexions entre ces bassins

durant le Paléocène ne soit pas clairement établie.

INTRODUCTION

In the Ulyanovsk'Saratov syncline of the Middle

Volga Région (Fig. 1) widespread early

Palaeogene seqiience (approximately .300 m

thick) is represented by marine siliceous-terrige-

nous deposits widi lilgli faciès diversity. Previous

srratigrapliic subdivision ot Palaeogene séquences

was based in most cases ori the liihological data.

The âge of these subdivisions and relations bei-

ween them hâve bcen révisée! by different investi-

gators more than once (Milanovsky 1940;

Leonov 1961; etc.). The high abundancc of sili-

ceous faciès, opokas (kryptogenc sUlceous depo¬

sits), the diatomites, siliccous clays and sands

offer advantage for siliceous microfossils study.

MOTS CLÉS

Paléogène,

biostratigraphy,

radiolaires,

silicoflagclJcs,

diatomées,

Moyenne Volga,

Plate-forme est-curopéenne.

430

GEODIVERSITAS • 1999 • 21 (3)

Palaeogene siliceous microfossils of Volga Région

Fig. 2. — Lithology and lithostratigraphy of the Sengiley section, stratigraphie ranges of siliceous microfossils, and zonation.

Schemes of Strelnikova (1992) (diatoms), Locker & Martini (1987) (silicoflagellates) and Koziova (1994) (radiolarians) were used.

l’his paper seeks to examine the evidence provi-

ded by siliceous microfossils — dnitoms, silico-

flagcllates and radiolarians which occur in the

Sengiley section. Scudy of siliceous micro-

organisms from this section is very crucial for

précisé âge déterminations of Palaeogene sedi-

mentary cycles and for revealing conditions of

silica accumulation on the northern Peri-Tethyan

margin. The problem of relations between thcsc

early Palaeogene biosilica accumulation events

and régional and global geologlcal events is also

of great interesi.

SENGILEY SECTION

The Sengiley section (Figs 1, 2) is located 7 km

north-west of the Sengiley (Ulyanovsk Région).

On chc right bank ofthe Volga River, at an éléva¬

tion of approximatcly 300 m above sea level, a

section of 40 m high cliff so-called "Granoe

üklto” was scudied. Up ro the section the follo-

wing Uthological units were disringuished in the

studied interval:

- at the river bank below the clifF siliceous grey

clays of 7 m thickness; no microfossils found.

GEODIVERSITAS • 1999 • 21 (3)

431

Khokhlova I. E. & Oreshkina T. V.

- siliceous dark-grey sandstones, thin-layered,

with silica clays lenses, lie at the base of thc

diatomite clifF; thickness 4-4.5 m; no microfossil

found.

- white massive diatomires with layers of lighr-

grey diatomires, sometimes with glauconite;

thickness 22 m; in samples 930109-930072

abundant siliccous microfossils werc found.

- light-grcy massive clayey diaromites lying

conform.ibly on the uudcdying unie; thiclcness

7 m; samples 930072-93057 contatn abundant

siliceous microfo.ssils.

- the unconformity separates thc diatomite unit.s

from ovcrlying sediment.s; they arc represented

by sandy brownish-green cla\^, siliceous greenish-

grey sands, brownish sandy opokas, silica dark-

grey opokas; thickness about 11m. Microfossils

were not found.

PREVIOUS STUDY OF SILICEOUS

MICROFOSSILS

Zonal subdivision of rhe Sengiley section on the

basis of radiolarians bas been proposed by

Kozlova (1984). The age was considered as late

Palaeocene. Radiolarian zones of diis scheme are

undoubiedly régional and can be traced in ihc

boréal epiconcinental Palacogenc of the Volga

and UraJ régions.

The study of diaroins of thc Middle Volga

Région vtas starred in 19th century by Ehrenberg

(1854), Grunow (1884) and Wirt (18%). Pater,

diatoms and silicoflagellates Irom tbis location

hâve been studied by Leonov (1961), Jousé

(1979, 1982), Gleser (1993, 1995; Gleser et aL

1977) and Srrelnikova (1990^ 1992). The lower

part of the diatomite unie is cerrainly related to

the Palaeocene by ail invesrigators, but an early

Eocene age is srill nor excliided for the upper

part of diatomires. Silicoflagellare assemblages

from several separated samples from ihe Sengiley

section were studied and dated by Locker 6c

Martini (1987) as early Eocene.

MATERIAL AND METHODS

Samples were collected during a field trip of

Russian Academy of Sciences Geological Institute

in 1994. 81 samples were examined for diatom

and radiolarian biostratigraphy, but siliceous

micro-organisms were found only in 55 samples

from che diaromite units of the section. Sampling

interval wa-s approximately 50 cm.

Approximately 5 g of sample was crushed

mechanically and placcd into an 400 ml bcalcer.

l'hcn samples wctc processed by 15'mJnutes boi-

ling in hydrogen peroxide. The procedure of

cepcatedly filling and decanring the bcakers with

distillcd waicr and allowing 2 hr scctling was

used to remove Chemicals and clay minerais.

Slides for radiolarian study were prepared on

24 X 24 mm cover glasscs and mounted in

Canadian balsam on 24 x 80 mm glass slides.

Radiolarians wcrc examined at X 400. Spccies

wcrc rccorded as abundant (A) if more titan

10 spécimens were présent in the slide, common

(C) if 3'10 specimeits occurred in the slide and

rare (R) if 1-3 .spécimens were found.

Strevvn slides for diatoms werc prepared by sam-

pling che suspended residuc with a pipette sprea-

ding il on 18 X 18 mm covet slide and mounting

in Elyashev moumirig medium, iliatoms were

examined ar X 500. Species identification was

checked at X 1250. Somc .samples wcrc studied

in SEM *T.’arnbridgc Srcrcoscan" microscope.

Relative abundance of taxa represented in the

range charr is reported as abundant (A) when

20 spccimens are présent in one horizontal tra¬

verse ac X 500, common (C) when 3-19 spéci¬

mens are présent at each traverse, few (F) -

1-2 specimens in each traverse, rare (R) — less

chan one specimen in each traverse.

STRATIGRAPHY

Rapiolaria

Using radiolaria, the section was subdivided on

che basis of rhe boréal zonal scheme of Kozlova

(1994). The zonal succession is Palaeocene

(Fig. 1, Table 1 ).

Buryell/t tetradica zone

The assemblage is moderately preserved and

contains Buryella tetradica Foreman, Theco-

sphaera rottmda Borissenko, Spongotrochus puter

432

GEODIVERSITAS • 1999 • 21 (3)

GEODIVERSITAS • 1999 ■ 21 (3)

Table 1. — Stratigraphie distribution of radiolaria in Sengiley section. A. abundant (20 specimens are présent in one horizontal traverse examined at x 500); C, common (3-19 spé¬

cimens are présent at each traverse); F, few (1-2 specimens In each traverse); R, rare (less than 1 specimen in each traverse).

AGE

ZELANDIAN

ZONE

BuryeUa

tetradica

Tripodiscinus sengilensis

' Species / sampla number

109

108

107

106

105

104

103

102

101

100

99

98

97

96

95

94

93

92

' Burva'da teuadea

C

R

LophophsôTxa curta

R

C

R

Plectodiscui: ïo\ch\li(rna

C

R

SoonoodiçcüS an\enc3nus

A

C

' SDOnoüdi^cuii vlina

C

R

C

R

SpoDQOirrichijs

C

R

SpoDQotrocttus sp ah Trainodiscus cleve

A

C

SponaQirocnus aH heiinr/BS

A

C

Sponpninychus pacfani’i

R

Spongcfnjchu^:, polcr

C

Thecosonacra rviunda

R

Tripodiccinus- seupiten^i^

C

R

1 Tripodiscinus Slbirii Üf^

R

Tripodiscinus irifcpalus’

R

_ ,

R

uj

AGE

ZELANDIAN-THANETIAN

ZONE

Tripodiscinus sigilensis

specles/sampie number

91

90

89

88

87

86

85

84

83

82

81

80

79

78

77

76

75

74

Anthoevrtoma fr/zzetf

R

LarnocatpiS smih

C

R

Lophophasna curta

- 1

R

--

R

Phormocv*tis- ^ailcuia

C

R

Plectodtscus t0tc^i//nae

C

R

Sponaoftoenue atf tietioides

C

R

C

SponQomeits&a tamaria

R

Tropodiscinus UHobafa^

C

R

C

R

C

Tripodisanus sengilensis 1

H

1

R

AGE _^_ ZELAND IAN-T HANETIAN _^_ THANETHiAN

ZONE _ Tripodiscinus sigilensis ____ Petalospyris foveoîata

species/sample number

73

72

71

70 ,

69

68

67 66 ; 65

64

63

62

61

60

59

58

57

^ I '

C

Boirvofreira esns

C

R

C

R

CfaihrccvcJX exisnss

R

Ciathroyj'çias iipm^nü

R

C/ar/jrocvctôs lonalsolna

A

-1

Dipiocvctas comuta runievae

C

R

A

R

C

Dipiocycias pseu(Sjùicorona

Dseudobiccrone

R

C

R

C

Penviaiuru'/ aumif^icdv

R

Peta/osovris toveoma

R

C

R

SoonQaetôTiscuç- otnziipfm

R

C

R

Sponaùnieîvssa îê/pàrid

C

R

C

SDondome/isaa numa ni/ma

R

C

Sponopifoenus nativus praecox

A

Stvlodyct\>a hadastonensh

R

A

R

C

R

Tripodiscinus trUobàtuS

R

3

Palaeogene siliceous microfossils of Volga Regioi

Khokhlova I. E. & Oreshkina T. V.

Kozlova, Trifwdiscinîis sibiricus Kozlova, Spongo-

discus americamis Kozlova, Spongodisms phrix

Gorboveiz and Lophophaena curta Kozlova. The

base of rhe zone was tint oKserved in the section.

The upper boundary is deterinined by the appea-

rance of Trîpodischms sengilensis Kozlova and

Plectodisciis totchUinae Kozlova.

Tripodhcintis sengilensh zone

Radiolarians are abundant and wcll-preserved.

The most common are: Tripodiscimts sengdemii

Kozlova, T. trilohatm Kozlova, Lophophaena

curta Kozlova, Spongotrochus paciferus antiquus

Kozlova, 5. atf. Troehodiscus clevêl (Ko7.1ovâ),

S. aff helioidei Clcve, Spongodlscus americü^ius

Kozlova & Gorbovetz and Pl^ctodiscus tochilinae

Kozlova. Sponolrocbus alveatui Riedel &

.Sanfilippo, Tripodiicinus sibirirus Kozlova,

Stylodiciya churlestonemis (Clark Campbell),

Anthocyrtoma frizz-eli Nishimura and PeriviaMri^.)

dumitriiae Nishimura occur rarely. Common

Larnocalpis smill Middour and Phoonocyrtis reti-

cula Kozlova & Gorbovetz were found in rhe

upper part of the zone. The upper boundary of

the zone is very sharp and determined by the

appearance of Petalospyrh fnveolata Ehrenberg,

Diplocyclas cornuta runjetw Kozlova, D. pseudo-

bicorana pseudobkorona Nishimura, Spongo-

melissa numa numa Kozlova, Clathrocyclas

longispina Clark & Campbell and Spongotrochus

nativuspraecox Kozlova,

Petalospyris fbveolnta zone

Radiolarians are diversifîed and well-preserved.

The most abundant are: Petalospyris foueolata

Ehrenberg, Dyplotyelns cormaa nmjevae Kozlova,

D. pseudobicorona pseudohicorona Nishimura,

Antocyrtoma pizzeli Nishimura, Botryornetra osha

Kozlova, Spongomelissn ternaria Kozlova, S. nurna

numa Kozlova. !n the lowct part ol rhe zone

Clathrocyclas longispina Clark Ôc Campbell, and

Spongotrochus nativus prnecox Kozlova are abun¬

dant. Spongasteriscus cruciferus Clark &

Campbell, Clatrocyclas extensa Clark & Campbell

and C. lipmanii Kozlova are rather rare.

Diatom.s and silicoflacellai ks

Pronounced taxonomie changes in diatom

assemblages observed in the middle part of

Sengiley diatomites (Eig. 1, Table 2) allow us to

distinguish frum the base and upsection two

zones of the zunal scheme for the Northern

Hemisphere sensu Srrelnikova (1990, 1992).

Trinacria ventrkulosa zone is represeiited bv com¬

mon TriceTatium mirabiU' Jousé, Trinacria ventri-

culosa {A. Schmidt) Gteser, Pyxidicula ferox

(Grevillc) Strelnikova & Nikolacv, Crunôwiella

gernmata (Grunow) Van Heurck. The assemblage

of the flemiaulus proteus zone consists of

FJendaulns inatrms Shibkova» H. proteus Heiberg,

H. incisus Hajos, H. frrgidtts (Grunow) Fenner,

Soleufii eX'SCulptum Heiberg, Taceratiurn heihergii

Gombos, Craspcdodiscus moelleri A. Schmidt,

Aulacodiscus suspectus A. Schmidt, Grunowiella

palaeocaenica Jousc and Cyiindrospira sirnsi

Mirlehner.

Bcsides thé siratigaphically important species

enumcraicd above, diversifîed représentatives of

the neritic diatom flora of epicontinental basins

.ire présent in both zonal assemblages. A lull ILst

is shown in the Table 1 and in the taxonomie

appendix.

Silicoflagellates (about 10 taxa) are common

throughout the wholc section. For stratigraphie

subdivision, the zonation of Locker & Martini

(1987) is applied. The appearance of memhers of

the ITavicttlopsis genus (including N. constricta

(Schulz) Frcnguclli, N. robusta Deflandre,

N. danica rcrch-Nielsen) defines Naviculupsis

constricta zone (upper Palaeocene-eavly Eocene).

Corhîsema disymmeiricû Bukry is présent ihrou-

ghout the whole section. According to Locker &

Martini (1987), this stratigraphie inrerval corres¬

ponds to the NP4-NP9 nannoplankion zones

and so gives as the po5.sibiIiry to restnet the âge

of the diaiomite unit by the Palneocene. Less

pronounced chan diaroms one, change in taxo¬

nomie composition is related to the middle part

of the section. This reconstruction includes the

last appearance of Dittyocha elongata Gleser and

the firsT appearance oï Naidculopsis punctilia

Perch-Nielsen.

PALAEOECOLOGY

Radiolarian assemblages are well preserved and,

for the epicontinental setting, diversifîed (33 spe-

434

GEODIVERSITAS * 1999 • 21 (3)

GEODIVERSITAS • 1999 • 21 (3)

Table 2. — Stratigraphie occurrence of diatoms and sillcoflagellaîes in Sengiley section. Legend: see Table 1.

Diatoms/Samples

109

108

107

106

105

104

103

102

101

100

99

98

97

96

95

-r

94

93

92

91

90

89

88

87

86

85

84

Aulacodiscus distinquendus

R

i

R

Aulacodiscus probabfJis

H

R

Briaaera sibirica

R

F

R

F

R

CostopyA^ arf/oua

R

i

Eunotoqratr.rrs \/af4dbi1e

R

R 1

R

, R

Euno\Dgranirré weissU

F

R

C

1

~3rün6w\eïîa ae<vmsi£

~Ar

~C~~

"TT^

A

C

F

C

F

~F

~C

C

F

C

“C

A

C

A

HemiauKJs friqiQa

C

R

C

R

C

R

C

R

Hem^au^L•s awbrguus

F

R

HëmJa~üiu& daoïcus

~ir~

-p-

R

H

R

Hemiaulos tncL'A'us-

R

Hem}aulus rossfcus

-

F

Hyalodiscos radistt'S

R

F

R

F

R

Kentrodisevs fos$))is

R

H

R

Lisitz fi^a d^tancr/i'

-1

R

Odonîoîrctxs caftna^s

R

F

R

F

R

! Odontatropis costara

R

Paralia CiV.nufata

R

F

R

Paralia orunewv/

F

R

F

R

Paralia sulcata

R

F

R

F

Probosàa cretacea

F

R

Pseodopodasira sp- 2

F

R

Pseudopodos^xB rtesfV

F

R

F

Pseudosticlod^cus argulaîus

R

F

R

H

Pterothecs maicr

R

H

Pyxid^-juia feroA

C

F

Rattrayalla oamarnensiS

R

Rhaphoneis morsiana

Rhaphonbun simbirskiana

R

Rhizosohnia hahblala

R

Stellarifti<'i niiomtons,

F

R

F

R

F

Thalaa&fosiin 1

R

Tbalar.sicslropsis yifUOana

C

0

C

F

G

C

Triceraiium Ûoa

R

Tricerativm kinkaïf

R

F

R

F

R

C

A

C

A

C

R

F

R

F

Tricefatsud) k-^'^tncvla^v

F

C

F

C

F

R

F

R

F

R

F

R

Trinacna pHeolus

R

F

R

F

■R

TrochosVa spinosa

R

Silicofiacieliales

Corbisama disvmmeinca

commi/nis

R

F

R

F

R

F

R

Corbisema has^*at3 basfata

F

R

F

C

CorbiSems oS'ibulata

R

H

R

F

H

Corbis-spia inem^-s inerniis

R

F

R

F

R

F

Dictyoeba elonçafa

C

F

C

F

R

F

R

Dictyocha

R

Dictyocha precarents

R

H

R

Navicuiopsis constneta

R

R 1 R

R

Naviciitopsis danica

R

Navic\nopsis roDus\a

R

l 3 _

R

H

R 1 R

R

Palaeogene siliceous microfossils of Volga Région

GEODIVERSITAS • 1999 • 21 (3)

4^

C^

1 Diatoms/ Samples

83

82

81

80

79

78

77

76

75

74

73

72

71

70

69

68

67

66

65

64

63

62 61

60

59

58

57

1 AulacodiscüS dfstinguendus

R

Aulaœdiscus prvbaùHis 1 R

R

H

R

H

R

F

R

Aulacodiscus schmidti ^

R

H

F

R

Aulaoodiscua suspecfus 1

R

H

R

F

^r~

C

~cr~

~c

~r~

A

r~

Briqpera sibiriM

F

R

Craspedodiscus moeliari

F

c

A

C

A

c

C

A

F

Cylindrospira simsi

R

C

EunoTOQramma variabile

H

R

Eunotoprammà weissU

R

Fenestreila antiQua

R

Grunow/etta gemmata

C

G

F

R

F

c

F

Grunowiella palaeocaenica

R

C

c

C

c

C

F

Hemiaulus ambtguus

R

Hemiaufus arcticus

var. bornholmensis

F

R

C

R

Hemiaulus cun/atuius

F

R

F

T”

F

R

Hemiaulus danicus

R

Hemiaulus frigidus

H

R

H

R

H

R

Hemiaulus incisus

H

R

Hemiaulus incunfus

R

Hemiaulus protevs

F

C

F

A

C

A

C

c

F

Hemiaulus rossicus

R

- 1

Hyalodiscus radiatus

H

R

F

R

F

R

F

R

Kentrodiscus fpssiiis

R

Lisitziniâ àtstanovlf

R

Odontotropis cannata

R

F

R

F

R

F

_R__.

F

R

Odontotropis cnstata

R

[ •

R

...

Paralia cronalala

R

h

G

C

F

R

F

“FT

“FT"

“R

“F^

R : R

“R

R

“Fr

TT

Paraha grunowii

1-

h

R

F

G

R

“FT-

TT

■R

“F^

“TT

Paraifa sûlcà'ta

h

G

A

F

A

“A~

-pr—

A

~A

“R“

Probosda cretaceé 1

R

“1^

R

F

R

R '

F

R

F

R

~R

"TT

TT

"TT

~R~

ir~

' PseudopDdosîra sp. 2

h

R^

R

Pseuoopodusira westii

h

A

G

F

R

F

R

^R

F

R

PseLxicxstic^dsc'js arH^ulatus

H

R

F

R

~F~

“F

R

~r~

R

Pterorbecà major

R

“FT

R

Pyxidlcülà môelhr!

R

F

G

C

F

~u~

“cr

C

~r~

R

Rattrayella 3ansariMos\s

F

R

F

Rattrayelia rcwndata

R

Rhaphpneis morstege

F

R

F

R

Rhaphoneis simbirskiana

F

R

F

R

F

R

F

C

F

R

Rhizosolenia hebetata

R

Solium exsculptum

R

F

R

F

R

F

R

F

R

Stellarima microtrias

R

h

F

R

F

^ F_

F

R

F

R

F

R

Khokhlova I. E. & Oreshkina T. V.

Palaeogene siliceous microfossils of Volga Région

N

LO

CL

X

CO

U)

ÛC

CE

CL

O

CL

X

O)

in

CE

LL

U

CL

CE

CL

X

O

(O

cr

ü

O

CL

LL

X

to

CE

lE

U

CL

LL

CM

(O

X

O

U

CL

X

CO

lE

CE

O

X

«T

(O

U_

CE

CL

ü

O

CL

X

tn

CO

ü_

CL

U

ü

CL

LL

X

(O

CO

lj_

Ll

ü

X

h.

CO

CE

tr

LL

O

X

CO

LL

CE

CL

LL

O

X

5

X

o>

CO

LL

CE

CL

ü

CL

X

O

h-

CE

tr

CE

CL

X

CE

CL

X

CM

h.

Œ

LL

CE

CL

X

«O

h.

CE

CL

X

Œ

X

V

h-

CL

CE

CL

°=

X

lO

h.

CE

CL

X

(O

h-

CE

CL

X

fs.

N

CE

CL

X

00

CE

CL

X

O)

r-

CE

CL

X

O

00

Œ.

CE

CL

X

CO

O

CE

CL

X

CM

CO

Ü

LL

CE

CL

X

CO

00

O

LL

CE

CL

X

O

X

Diatoms/ Samples

w5

O

<0

CO

iS

CO

c:

to

t:

§

a

VJ

t-

§

î

•S

CD

e

E

5

1

S

1

(b

sQ

£

E

%

5

C

Ol

<<

1

S

5

II

S!

1'

iS

nj

5

jJ;

S

5r

Ç’

3

Tnceratium veotneubsum

0}

i

1

?

i

Q

S.

5

b

1

O)

2

S

ü

1

g

1

s

g

S

ë

ci

CO

Vi

i

1

5

s

1

ts

$ ttj

fe c-

11

8 8

s

ÜJ

U.

r.

c

s

42

J

i

a

8

43

to

-Ci

i

I

ai

11

1

LD

Ç

1

•e

8

CO

1

09

ta

c

11

Q

48

3

JO

«

m

i

.ü

Q

VI

1

8

Q.

en

L9

O

Q

NaviculQpS!S constficta

§

1

Î2

(O

a

S

Naviculopsfs punctiha

Navfculopsis robusta

cies were dctermincd). Different radiolarian spe-

cies dominatc the assemblage in spécifie strati¬

graphie intervals. hor example, specimens of

Sporigodisciis umerivanus Kozlova & Gorboverz

dominatc in the lowcrmost part of section

(samples 109-104), 'rripociiscinus sengilensis

Kozlova in samples 106-101, Spongohvchin

helîoida (Cleve) in santplc.s 99-88, Tripodheinm

trilohntus Ko/lova in samples S7-75, Antho^

cyrtonui frizzeli Noshiniura and Petahspym foi^ea'-

lata Ehrenberg in samples 65-60. Generally, in

the lower part of diatomicc unit, représentatives

of the Spongodiscidac lamily (généra

Spnngüdiscus and SpongoLrochuA and Irisso-

cyclinae iarnily (genus Tripodiicinus) are domi¬

nant, and in ihc upper part of diaromites speci¬

mens of tlie Cyrtidav (généra Diplocyclas^

Clathrocycla^ and Anîhocyrtoma) and ol the

Spyridae (genus Petalospyris) dominatc. The

grcatest change of thé assvxiation can be obser-

ved at the stratigraphical level of samples 72-67

(Fig. 2), on the boundary between the Tripo-

dischius se7igilensis and Petalospyris fot'eolata

radiolarian zones.

Diatom assemblages are well preserved and taxo-

nomically diversified too. represented mainly by

robusi, large frustules of diatoms. About 60 taxa

of diatom W'cre decennined. The diatom assem¬

blages arc dominated by species t)'pical tor neti-

tic environment. Fully planktonically living

species arc represented by généra TJemiaulus,

Rhizosoletua, Proboscia. Thalussiosiropsis and

Trkeratlnm.

In the upper part of the section (samples 80-71)

a taxonomie turnover in diatom assemblages cor¬

rélâtes wiih relative increase of the Paralia sulcata

(Ehrenberg) Cleve group. le is possible diai ihese

changes restify the transition to the coastal, .shal-

low'er environment. The same trend is reflected

in the increasing of clayey material content in

the upper part of the section and in the change

of diatpmites colour from white to grey

DISCUSSION

Stratigraphic issues

The précisé âge détermination of siliceous

GEODIVERSITAS • 1999 • 21 (3)

437

Khokhlova I. E. & Oreshkina T. V.

Fig. 3. — The stratigraphie position of the diatomites of the Sengiley section and corrélation to standard and régional zonal schemes.

microfossil.s associarion.s from the diatomite unit

of the Sengiley section is very important to

understand the stratigraphie position oF the

Middle Volga sÜiceous sediment.s (Fig. 3).

Présent knowledge of stratigraphie ranges of

Palaeoccne dratoms and radiolarians is very liini-

ted, espccially for the epieontinentaJ basitis. As a

rule sediment.s do not contain any calcareou.s

plankton and do not hâve not any pulaeomagne-

tic data.

Bcsides in the Volga Région, rhe Bnryelld tetnl-

dica radiülarian zone can be distinguished in chc

North Prccaspian Basin; the Tripodiscinm sengi-

lensis zone can be observed in rhe Serov

Formation of tlie eastern Ural slopc and of the

western Siberia; and the Petidospytis faveolata

radiolarian zone can bc recognised in the Irbii

Formation of ihc eastern Ural slope (Kozlova

1984). These radiülarian zones are ihus régional

and can be traced across a wide lerritory.

Radiolarian zones distinguished in this paper

were referred to the upper Palaeoeeiie by Kozlova

(1994) on the basis of a few species common to

the associations Irom the Guif Mexico

(Foreman 1973).

\Ve suggesr thar the Bi^ryella tetradica and

Tripodiscinus sengilensis zones are relaied to the

lower Bvkouta campvchensh zone of ihe standard

radiolarian icale. in regard of the presence of

Buryella ttimdicd Foretnan, l'hecdsphiiera ronwda

BorLssenko, Spangodisetis amerîcanuy Kozlova ÔC

Gorhovetz, Spoiigotrot'hui ttlpcdtus Riedel 6c

Sanlllippo and Penviator (?) dumitricai Nishimura.

Bascd on the presence of DiplinycLîs pseudvbi-

coninn pseudobicorona Nishimura, Spoitgasttriscus

rruciferus Clark ÔC Campbell and Antho-

cyrtoniit (?) frizzelli Nishimura, the Petalospyris

foveoLtta zone .seems lo correspond to the upper

part of Bekoma cdmpechensis zone of the

Northwest Atlantic and, cornespondingly, to the

CP5-CP6'lower CP7 nannoplankron zones

(Nishimura 1992).

A similar piciurc is obiaincd Irom the diatom

stratigraphy. 'fhc samc succession of diarom

assemblages ( Trinacria venlriculosa and

Hemiaulus protem zones) is typical for the whole

438

GEODIVERSITAS • 1999 • 21 (3)

Palaeogene siliceous microfossils of Volga Région

regioti:, being reporied from the boundary inter¬

val bervveen the Jower and middie parts of the

Lulinvorr Formation (Pur and Taz River basins)

of western Siberia, the îrbit and Serov (ormarions

of the eastern Lirai slopc (Proshkina-L^avrenko

1974). Unforiunately, the précisé âge of tliese

régional subdivisions remains unclear, for they

can still not be correlated with the standard zonal

schemes of calcareous microplankton.

Strelnikova (1990, 1992) puis the foregoing

zones into the latc Palacocene. Gleser (1994,

1995), che firsr vvho discinguished these zones,

considered the lower zone as late Palaeocenc and

upper one as early Eocene. But, it is clear now,

that for the subdivision of the Sengiley section,

standard diatom zones, which werc dircctly cor-

related wlih nannoplankton zones in sections

from Southern Indian Occan (Fourtanier 1991;

Barron ik Baldauf 1995) can be used (Fig. 3).

The taxonomie composition of the upper

Ht^mifzuhis proUi^s zone is like that of the

Hemiatilus incurvus standard zone. The sharpiy

diiferent assemblage of the lower Trinucria tm-

trtadosa zone allows us to corrclatc this interval

lo the Hem 'untliisperiptertis zone. Thèse standard

diatom zones correspond to rhe NP4-NFT 1 nan¬

noplankton zones (Fig. 2). However, the présen¬

ce in ail associations of the siliconagellate

Corbiserna disymmetriva Bukry, which i.s known

only from the NP4-NP9 interval, allows us to

siiggcsL that the Sengiley diatomites are wiihin

the Palaeocenc.

Thus, in ail threc (radiolarian, diatom, and sîlico-

llagcllate) assemblages, there are a number of stra¬

tigraphie markets which can be successfuUy used

for the stratigraphie subdivision of early

Palaeogene sédiments and for the refinemeat of

Palacocene diatom zonation. These the diatom

spccies Ai4Ltcodiscu% sus>p€ctus A. Schmidt,

Hemhwlîis prokus Heiberg, moelleri

A. Sedrmidt, Cylhulraspha shm't Mitlehner; and the

radiolarian species Tripodhchitn sengilensis

Kozlova, T. trilohatus Koziova, T. sibirkus Ko/lova,

Petalospyris foveol^ita Ehrenberg. P. fhccUa Kozlova,

etc. Until now, these radiolarian species hâve not

been found in open océan sédiments.

Palaeogeographic issues

During the middle-late Palacocene, the Middie

Volga Région vvas a shallow-water, highly pro¬

ductive marine basin with siliceous sédimenta¬

tion. It is obvious that Palaeocenc sédiments of

the Middie Volga Région are accumulated in the

great guif of the epicontinenral sea, via an inten¬

sive iipwelliug proces.s. L3istanov (1968) suppo-

sed thaï diatomites niay be accumulated in

marginal pans of palaeodelias. It is possible also

that diaromite accumulation took place only on

topographie highs of subbottom relief,

l’hc main pcculivirity of the siliceous micropJank-

ton assemblages is their provincialistn. The taxo¬

nomie composition of the associations differs

strongly from coevul oceanic assemblages. Deep-

sea diatom Palacocene a.sscmblages, restricted

generally to the Southern Hémisphère (Fcnncr

1991; Fourtanier 1991) differ caxonomically

from epiconcinental assemblages duc to palaeo-

ecological and palaeogeographical différences,

and préservation factors. Epicontincntal diatom

assemblages of the Northern Hemisphere are

highly diverse due to high percentages of mero-

planktnnic species.

Althûugh Palacocene diatom as.semblages from

the Southern Hemisphere and Volga Région dif¬

fer srrongiy, rhe présence of cominon spccies sug-

gests a connection bctvvccn thc.se arca.s o( the

World Occan, possibiy through rhe Terhys and

East Atlantic. The geography of tlie connection

between Middie Volga Région and West Siberian

ba.sins (includmg the eastern Urals slope), and

the Noriii European basins (Fur Formation,

Denmark and Sambian Formation, Kaliningrad

Région, Russia) with biosilica sédimentation

(Strelnikova et al. 1978; Fenner 1994; Mitlehner

1996) is not srill clear.

Acknowledgements

Wc would like to thank Prof. J. Meulenkamp

(Utrecht Universicy, Netherlands) and Prof.

D. La/arus (Berlin, Germany) which improved

the manuscripr, Prof. P De Wever and Dr S.

Crasquiu-Soleau for general coordination and

advice on this work, which is part of the Peri-

Tethys Prograrn (Grant.s 95-11 and 95-96/1 1).

The other sponsor was Russian Science

Foundation (Grant 05-95-15002).

GEODIVERSITAS • 1999 • 21 (3)

439

Khokhlova I. E. & Oreshkina T. V.

REFERENCES

Barron J. A. & BaldaiifJ. 1995. — Cenozoic marine

diatom biosiratigraphy and applications to paleocli-

matology and paleoceanography in Blome C. D. et

al. (cds). Siliceous Mierofth^^ih. PalcontoUi^ical

Sociery Shon Cormes in Palr 0 fuolii^> S: 107-11 H.

Berggren W. A., Kent D. \7, Svvisher C! C. & Aubry

M.'P. 1995. —A revïseci ccno/oïc w’othn)n()log\'

and chronosrrnrigrjpliy. (teochromm^' lime svale

and global jiratigralmw conriatnm, SLPM (Societ)*

for ScdimcntaiY Gcology), spécial publication 54:

129-2J1.

Bjorklund K. R. 1977. — Radiolaria front the

Norwcgian Sea, Leg 38 of rhe Deep Sea Drilling

Project. Initial Reports of the Deep Sea Drilling

Project 38: 1101-1108-

Borisenko N. N- 1960. — New radiolaria of the

Palacocene of the West Ruban River basin.

Publicdtion of Krasnodar town Otl and Cas boititute

4: 199-208 |m Russian).

Bukry D. 1976. — Cenozoic silicafiagcllates and coc-

coliih stririgraphy, Sourh Atlantic océan, Deep Sea

Drilling Project Leg 36. Initiai Reports of the Deep

Sea Drilling Project 35: 885-'9I7.

Clark B. 1,. Campbell A. Schmidt 1942. — Eocene

Radiolarian Faunas from the Mt. Diablo area,

California. Gcological Society of America Spécial

Paper 39, 112 p.

Dumimea P. 1973. — Palaeoccnc radiolaria. DSDP

Leg 21. Initial Reports of the Deep-Sea Drilling

Project 1\ : 787-817.

Fenner J. 1985. — Late Crefaceous Co Oligocène

plankcic diatoms: 713-762, in H. M., Satiders

J. B. Perch-Xielseii K. (edsK Planhton Stratigraphy,

Cambridge University Pres.s, C^ambridge.

Fenner J. 1991. — faxonomy, stratigraphy. and

paleoceanograpbic implications of Palaeocene dia-

toms. Procccaings of the Océan Drilling Program^

Scientific Ri\ndrs 114: 123-154.

— 1994. — L)iattMns of ihc Fur Formation, their

taxonomy and biostiatigrapliic interprctation.s.

Resulrs from the Harre horehole, Denmark. Aarhus

Geoscicncc, Aarhus 1: 99-163.

Foreman 11. 1973. — Radiolaria of Leg U) with sysce-

matics and ranges fo^ the lamilies Amphyndacidae,

Anostrobiidae, and Theoperidae. Initial Reports oj

the Deep Sea Drilling Project 10: 407-467.

Fourtanier E. 1991. — Palaeoccnc and Eocenc dia-

tom stratiginphy and raxonomy of Eascern Indian

océan site *^52. Proceedings of the Océan Drilling

Progrtiim Seientifïc Rendes î 14: 171-187.

Frizze f D. L. & Middour E. S. 1951 — Palaeocene

radiolaria Irrnn Soütheastern Missouri. Bulletin of

the LhthersiTy of Missouri, School Mines Meial-

logeny, lechnical scrie. 77. 41 p.

Gleser Z. 1. I960. — Palaeogene stlicoflagellates of

western Siberia. Stratigraphia i Paleontologia, VSE-

CiEl, Inform.irzioniy sborntlc 35: 127-136 [in

Russian].

— 1966. — Siliconagcllatophvceae, in Gollerbakh

M. M. (cd.) Cryptogamie plants of the VSSR.

Volume 7. Akademy Nauk SSSR, Botanischeskiy

Institut. .Moskwa'Leningrud, 330 p. |in Russian].

— 1984. — rUc significance ol taxonomie studtes of

diaiorns for biastratigraphy and paieogeography.

Ejtgodnzh paleontologischeshogo ohstchesiva 27:

2S4-298 [in Russian 1.

— 1993. — New data about the Ulyaiiovsk Volga

Région Lower Palaeogene subdivision and corréla¬

tion on diatoms and silic<illdgellart\s, Bulletin

RM SC on the Centre and South (f the Russian

Phnform^ Mosçow, Publication 3: 120-123 [in

Russian].

— 1994. — The correl.ition of P.ilaeogetie diatom

flore évolution from epicontinental and oceanic

arc-as. StYtuigraphy andgeologieui corrélation, Nauka,

Mo.scow 2(1): 103-107 (in Russian).

— 1995. — L^iatoni und silicoflagcllate assemblages

as indicaiors of synchronou.s occurrence of diato-

miies of Middle Voiga région. Denmark atid Power

Palaeogene oceanit b{}tiijm sédiments; 57-63 [in

Russiatij, in Barash M. .S. (ed.l. Rccent and fossil

microplankwu'ofthe WorLi Océan, Nauka, Moscow.

Cileser Z. 1., Kuzntrsov.i T. A. ik Afana.syeva N. I.

1977. — About âge and facial position ut the

MiJdle Volga diatomites. Sovetskaya Geologia 8:

113-119 [in Russian].

Gleser 7. I. &L Rubina N. V. 1908, — New

Palaeogene diatom specie, genus Cascinodiscus

Ehrenberg Trudy Tumen InduSttial Instimte 1;

153-155 (in Riissian].

Gombos A. M. 197". — Palaeogene and Neogene

diatoms from the Falkland Plateau and Vlalvinas

Ourer Basin: Leg. 36. Deep Sea Drilling Project.

Initial Reports of the Deep Sea Djil/in^ Project 36:

575-68^.

Hajos M. 1976. — Dpper Eoccnc and lower

Oligocène diaiomaccae, archaeomonodaceae, and

silicoflagellatae in Southern Pacific sédiments,

DSDP I cg. 29. Initial Reports of the Deep Sea

Drilling Project 35: 817-883.

Hajus M. tk Sîjdncr FI. 1975. — Late Octaceous

archacomonadaceae, diâtomaceat, and Mlicoflagel-

latae from the South Pacfllc Océan. Deep Sea

Drilling Project, Leg. 29. Site 275. Initia! Reports

ofthe Lteep Sea Drilling Project 29: 913-1009.

Harwood D. M. 1988. — L'pper CretaCeouS and

Power PaUcoGcne diatom and silicuflagellatossirati-

graphy of Seymour Island, eastern Atuarcric Penin-

sula. GeoltigiculSociety oj Anierica 169: 55-129.

Haslc G. & Si ms P. i986. — The diatom genera

StelLirima and Symbolophont viwh contments on the

geniis Aetinoptychus. British Phycological Journal 21:

97^114.

Hasie G. P. 6c Syversten E. E. 1985. — Thulas-

siosiropsis, a new diatom genus from the fossil

440

GEODIVERSITAS • 1999 • 21 (3)

Palaeogene siliceous microfossils of Volga Région

ïtcords,. Aficropaleonwlogy 31 (I): 82-91.

Homann M. 1991. — Die Diaromeen der Fur-

Formarion (Airtcrriar) aus dein LtiTif]ord-Gebiet,

Nordjutland/Danemark. Geohÿische juhrhuch 123,

285 p.

jordan R. W. & PriJdlc j. 1991. — Fossi! niembers

ol the diatom genus Proboscid. Diutvm Research 6

(1): 55-61.

jousé A. P. 1951. — Upper Creraceus diacom.s and

silicoflagcllateÿ, North Ural. Butankheykye mciterialy

nidelti spornvykh ra^^teniyy Boranic^l Instiiüic of

Akademia Nauk SSSR 7: 42-65 (in Ru«ian|.

— 1955- — New species of Palaeogene diatoms.

Botnnichesk're materialy otciela sporovykh rastemy^

Botanical Insiitutc of Akademia Naulc SSSR 10:

81-103 lin Rus-îlan).

— 1979. — Diarom biostratigraphic zones ol the

Eocene. Nowtf Hedwigui 64; 427-440.

— 1982. — Palaei'^cene diatoms and silieonagellaies

Irom the Pacific, Indian and Atlantic océans:

131-145 [in Russian], in Jousé A. P. &:

Krasheninnikov V. A. (eds), Aiorskaya mikropaleo'

tologia. Nauka, Moscow'.

Ko/.lova G. E. 197S. — Zonal subdivision of the

Cretaccou.s/Palaeogene boundary levels on plankto-

nic organi.sm.s, in Zitmal siratigniphy of the boréal

Upper PalvQX>oic and Aîczosow as the base far sîtuiy of

oit-beariiig sedinicnts of the North Russia^ Siberta

and KtizakhsuiH- Materialy VNIGRI, Leningrad,

181 p. lin Rn$sian|.

— 1984. — Zonal subdivision ol the boréal

Palaeogene on radiolarians in Morphoio^s ecology

and évolution af Radhlaria, Materials of the IV

European Meeting on radiolaria (Hurorid-lV).

Nauka, Leningrad: 196-210 [in RussianJ.

— 1990. — Filogeneiic investigations as the base lur

zotial scalc on radiolariaiis oi the boréal Palaeogene:

"^0-81 lin RussianJ, m Radioluria in Biostratigraphy,

Academy of Sciences ol USSR, Sverdlovsk.

- 1994. — Radiolarian /.onal .scalc of ihc boréal

Palaeogene. Mityopaleontology {spécial publication)

6: 90-93.

Ko/.lova G. F. & Gorbovci/ A. N. 1966. — Upper

(iretaceous radtolaria of (ht West Siherian Basin.

Nedra, Leningrad, Î59 p. (in Ru.ssian].

Kroirtv A, I. &: Shibkova K. (J. 1959. — Kew^ diatom

species from the Urals Pal.icogcne depoiits,

Botanieheskie materialy otdela sporùvykh rasienh,

Botanical Institucc ol Akademia Nauk SSSR 12:

112-129 lin Ru.ssian].

Leonov G. P. 1961. — Main problevh ofthe Russian

plate Palaeogene régional stniiigraphy. Moscow State

Univer.sity^ Moscow, 552 p. [in RussianJ.

Locker S. & Martini E. 1987. — Silicoflagellaten au.s

einigen russistheo Palaogen-Vorkommen. Senc~

kenberguina kibaea 68 (1/4): 21-67,

Makarova I. V, (ed.) 1988. — The diatoms of the

USSR fassil and recent. Volume 2, fasc. 1. Nauka,

St.-Petersburg, 116 p. [in RussianJ.

— 1992. — The diatoms oftbe USSR fossil and recent.

Volume 2, lasc. 2. Nauka, St.-Petersburg, 125 p.

lin RussianJ.

Miianovsky E. V. 1940. — Geology of the Middle and

Power Volga région. Go.stoptecknizdat, Moscow,

276 p. lin Russianh

Miilehticr A. G. 1995, — Cylindrospira, a new diarom

gemts from ihc Palaeogene of Denmark with

palaeoccological significancc. Diatom Research 10:

321-331-

— 1996. — Palacocavironments in the North .sea

basin *ari»und the Paleocene-Eocene boundar)': évi¬

dence from diatoms and olher siliceous microlos-

sils, in Knox R. W. O'B., Corfield R. M. & Dunay

R. F. (ecLs), Corrélation of the Early Palaeogene in

Northwest Europe. Geological Society spécial publi¬

cation lOI: 255-273.

Mukhina V. V. 1976. — Species composition of ilu*

Laie Palaeoccne diatoms and silitoHagclIate.s in lhe

Tndian Océan. AVnropaleontohgy Zl: 151-158.

Ni.shimura A. 1992. — Paiacocene radiolarian bio-

srraiigraphy in tlie norrhwest Atlantic at Site 384.

Leg 43, uf fhc Deep Sea DrilUng Projecr.

Microp{ileoniolog^> (4): 317-362.

Perch-Nielsen K. 1976. —- New ^ilIcolLigeJlaics and

silicofLigeilate zonation in North Furopean

Palaeoccnc and Eocene di.uonijte. Bulletin of

Geological Society of Denrnark 25 ( 1 *2): 22-27-

— 1985. — Silicoflagcllates: 811-846. tn Bolli hl. M.,

Sauders I. B. ôc Perch Nielscn K. (eds), Plankton

itratigraphy. Cambridge University Press,

Cambridge.

Petrusbevskaya M. CE 1971. — Radiolaria of the

World Océan. Investigations of the Alarine fauna.

Naulo. Leningrad, 416 p. |in RussianJ.

Perrushevskaya .M. C, & Kozlova G. E. 1972. —

Radiolaria. Inuial Reports of the Deep Sea DrilUng

Project 14: 495-654.

— 1979. — L3escriprions of rhe gênera and species of

radioUria: 86-111 [tn Ru.ssian). in Srrelkov A. A. ôc

Peirushevskaya M. G. (eds). lîistory of the

Norwegian Sea Mkroplanktou. Nauka, IvCningrad.

Proshkina-Lavrenko A. J. (ed.) 1949, — Diatomoviy

Analis, Volume 2. Akademi.a Nauk SSSR, Botanical

Institutc, Moscow-Leningrad. 238 p. (in RussianJ.

— 1974. — The diatoms of the USSR finsil and recent.

Volume 1. Naxika, Leningrad, 403 p. |in RussianJ.

Riedcl W. R. & Saidllippo A. 1971. — Cenozoic

radiokrLj from the western tropical Pacific. Initial

Reports of the Deep Sea DiilUng Project 7;

I529-166S.

Ross R. & Sims P. A. 1985. — Some généra of the

Riddulphuceae (diatoms) wirh interlocking linc-

king .spincs. Bulletin of Britisb Aiuseurn of Natimil

lîistor^f (Botamc) 13 (3): 277-381.

Sanfilippü A. èc Riedel W. R. 1973. — Ccno/oïc

radiolaria. Initial Reports af the Deep Sea DrilUng

Project 10: 475-811.

Schrader H.-J. & Fenner J. 1976. — Norwegian sea

GEODIVERSITAS • 1999 • 21 (3)

441

Khokhlova I. E. &c Oreshkina T. V.

cenozoic diatom biostratigraphy and taxonomy.

Initial Reports of the Deep Sea Drilling Project 38

(Part 1): 921-1099.

Sheshukova-Poretzkay V. S. & Gleser Z. I. 1964. —

New Palaeocene marine diatoms of the Ukraine:

78-92 [in Russian], in Novosti Systematiki Nizshikh

Rasteniy. Akademia Nauk SSSR, Botanical

Institute, Nauka, Moscow-Leningrad.

Strelnikova N. I. 1971. — New diatom species of

Upper Cretaceous .sédiments of the Eastern slope of

the Polar Ural: 41-51 [in Russian], in Novosti Syste-

matiki Nizshikh Rasteniy. Akademia Nauk SSSR,

Botanical Institute, Nauka, Moscow-Leningrad.

— 1974. — Late Cretaceous diatoms (Western Sibiria).

Nauka, Moscow, 203 p. [in Russian].

— 1990. — Evolution of diatoms during the Creta¬

ceous and Palaeoeene periods: 195-204, in Simola

H. (ed.), Proceeaing of lOth Diatom Symposium.

Koeltz Scientific books, Koenigstein.

— 1992. — Palaeogene diatoms. St-Petersbourg

University Press, St-Petersburg, 321 p.

Strelnikova N. I., Kaplan A. A. & Travina M. A.

1978. — Palaeogene diatoms, silicoflagellates, ebri-

dian of Kaliningrad district: 57-66 [in Russian], in

Jousé A. P. (ed.), Morskaya micropaleontologia.

Nauka, Moscow.

Strelnikova N. 1. & Nikolaev V. A. 1986. — The

review of généra Stephanopyxis and Pyxidicula

(Bacillariophyta). Botanischeskyi journal 71 (7):

950-953 [in Russian].

Submitted for publication on 22 April 1997;

accepted on 30 June 1998.

442

GEODIVERSITAS • 1999 • 21 (3)

Palaeogene siliceous microfossils of Volga Région

APPENDIX

DIATOMS

Actinoptychtis sp.

Aulacodiscus distingueiidus Hustedt (1958) —

Homann 1991. pl. !■» fig. 4.

Aulacodisciis probabilis A. Schmidt — Homann

1991, pl. 4, % 3-5 (Fig. 7K).

Aulacodiscus schmidtii Win (1886) — Aula-

codisciis sepuis A. Schmidt 1. septvs A. Schmidt

Srrelnikova 1974, pl. 19, (igs 1-6, tah. 20, figs 1-

5. (Fig. 7F).

Aulacodiscus suspectas A. Schmidt (1876) —

Flomann 1991: 37, pl. 6, Figs 1-5: pl. 7, Figs 1-3,

5 1= Coscimdicus josefinus Grunow — Strelnikova

et al. 1978, pl. 15, Figs 1.2] [= Coscinodisais iira-

/i’/n'A fousé — Proshkina-Lavrenko 1949: 73,

pl. 24» fig. 4 (Fig. 6K)1.

Briggera sibirica (Gainow) Ross ôc Sims, 1985:

300, pl. 3, figs 1-7. — Homann 1991: 74, pl. 8,

Figs 1-11 [= Riddulphia tuomeyi (Bailev) Roper

var. tridenut Jousé — Strelnikova et aL 1978,

pi. 17> Fig. 5 (Fig. 5D)].

Coscinodiscus anissbnovae Gleser & Rubina,

1968.* 153. pl. 1, Figs 1-6. — Pro.shkina-Lavrenko

1974, pl. 38, Fig. 8.

Coscinodiscus sp. Common occurrence of large

Coscinodisciis ts rccordcd at the Scngiley section.

These belong moscly to Coscinodiscus oculus iridîs

Ehrenberg (1839) group. Coscinodiscus mdiatus

Ehrenberg (1839) group, and Coscinodiscus argus

Ehrenberg (1838),

Costopyxis nntiqua (Jousé) Gleser, 1984; 291

Stephanopyxis antiqua Jousé, 1951; 46, pl. 1,

Fig. 3. - Strelnikova 1974, pl. 3, figs 18-20].

Craspedodiscus moelleri A. Schmidt (1893) —

Pro.shkina-l.avrenko 19‘74, pl. 23, fig. 2. -

flomann 1991: 47, pl- 17, Figs 1-5 (Fig. 6D).

Cylindrospira sitnsi Miilehner, 1995: 323,

Figs 3-6, 9-18 [= Pyxilla multiseptata Gleser,

1995, pl. l, fig. 16 (Fig. 6B)J.

Eunotogramma variabile Grunow (1883) -

Proshkina-Lavrenko 1974, pl. 15, fig. 12

(Fig. 5E).

Eunotogramma weissii Ehrenberg (1955) -

Proshkina-Lavrenko 1974, pl. 5, fig. 6 (Fig. 4A).

Fetiestrella antiqua (Grunow) Swatman (1948)

- Homann 1991, pl. 18, figs 1, 2, 4, 5.

Grunowiella gemmata (Grunow) Van Heurck

(1896) — Fenner 1991, pl. 11, fig. 13 (Fig. 6H).

Grunowiella palaeocaenica ]o\\sC 1951: 40-4l»

pl. 4, fig. 5. - Fenner 1991, pl. II, figs 1-4

(Fig. 61).

He?nialus ambiguus Grunow (1884) — Fenner

1994, pl. 6. fig. 17{Fig. 5B, I).

Hemiaulus arcticus van bornholmensis Cleve-

Euler (1951) — Fenner 1994, pl. 8, Figs 1, 2

(Fig. 5F).

Hemiaulus curvatulus Strelnikova, 1971: 49,

pl. l, figs 12, 13. - Harwood 1988, figs 12, 13

(Fig. 50, S).

Hemiaulus danicus Grunow (1878) - Homann

1991, pl. 20, figs 1-10 (Fig. 5N).

Hemiaulus jrigidus (Grunow) Fenner, 1994:

112, pL 8, fig. 4 (Fig. 5C).

Heiniaulus incisas Hajos, 1976: 829, pl. 23.

figs 4-9, — Fenner 1991, pl. 10, fig. 9 (Fig. 5G).

Hemiaulus incurvas Shibkova in Krotov &c

Shibkova, 1959: 124, pl. 4, fig 8. - Gombos

1977, pl. 16, figs 1-7 (Fig. 5A).

Hemiaultes proteus Heiberg, 1863 - Proshkina-

Lavrenko 1974, pl, 19, fig. 3. - Homann 1991,

pl. 24, figs 15-18 (Fig. 5P, R).

Hemiaulus cf. rossicus Pantoesek, 1889 -

Proshkina-Lavrenko 1974, pl. 15, fig. 10

(Fig. 5L, M).

Hyalodiscus radiatus (O’ Meara) Grunow var.

arctica Grunow (1884) — Homann 1991, pl. 26,

figs 3, 6-9.

Kentrodiscus fossilis Pantoesek (1889) -

Harwood 1988, figs 16-18 [= Pterotheca sp. -

Homann 1991, pl. 54, figs 7-9 (Fig. 7G)].

Lisitzinia distanovii Gleser, 1995, pl. 1, fig. 5

(Fig. 4C),

GEODIVERSITAS ■ 1999 • 21 (3)

443

Khokhlova I. E. & Oreshkina T. V.

Fig. 4. — A, Eunotogramma weissii Ehrenberg, sample 100; B. E. Trinacria excavata Heiberg; B, sample 68; E. sample 58;

C. Lisitzinia distanovii Gleser, sample 69; D, Triceratium mirabile Jousé, sample 100: F, Triceratium sparsipunctata Jousé.

sample 67; G. Solium exsculptum Heiberg. sample 58; H. Trinacria regina Heiberg. sample 61; I, Triceratium ventriculosum A. S.,

sample 100; J, Triceratium flos Ehrenberg, sample 100; K, Triceratium heibergii Grunow, sample 58. Scale bar: A, B. D. G. I, J,

26.6 pm; C, 13.3 pm; E, 28.5 pm; F, 40 pm; H, 20 pm; K, 23.5 pm.

444

GEODIVERSITAS • 1999 • 21 (3)

Palaeogene siliceous microfossils of Volga Région

Fig. 5. — A, Hemiaulus incurvas Shibkova. sample 85; B. I, Hemiaulus ambiguus Grunow. sample 85: C, Hemiaulus frigidus

(Grunow) Fenner, sample 67; D. Briggera sibihca (Grunow) Ross & Sims, sample 58; E. Eunotogramma variabile Grunow,

sample 88; F. Hemiaulus arcticus var. bornholmensis Cleve-Euler, sample 103; G. Hemiaulus incisus Hajos. sample 58; H, J. K,

Hemiaulus sp.; H. sample 103; J, sample 109; K. sample 109; L, M, Hemiaulus cl. rossicus Panlocsek. sample 67; N, Hemiaulus

danicus Grunow. sample 88; O. S, Hemiaulus curvatulus Strelnikova; O, sample 58; S, sample 67; P. R. Hemiaulus proteus Heiberg;

P. sample 58: R, sample 61 ; Q. Hemiaulus sp., sample 75. Scale bar; A-C, E-N, R, S, 20 pm; D, 0-Q, 26.6 pm.

GEODIVERSITAS • 1999 • 21 (3)

y ^

1

E.

% *

Khokhlova I. E. & Oreshkina T. V.

Fig. 6. — A. Rhaphonels simbirskiana Grunow & Pantocsek, sample 58; B. Cylindrospira simsi Mitlehner, sample 67; C. Pyxidicula

ferox (Greville) Strelnikova & Nikolaev, sample 100; D. Craspedodiscus moelleri A. Schmidt, sample 58; E. Pyxidicula ft/ms {Greville

& Arnott) Strelnikova & Nikolaev. sample 100; F, Thalassiosira sp. 1 sensu Fourtanier, sample 59; G. Pyxidicula sp., sample 74;

H. Grunowiella gemmata (Grunow) Van Heurk, sample 100; I, Grunowiella palaeocaenica Jousé, sample 58; J, Thalasslosiropsis

wittiana (Pantocsek) Hasie, sample 100; K. Aulacodiscus suspectus A. Schmidt, sample 58; L. Pyxidicula sp.. sample 58. Scale bar:

A. H, K, 16.6 pm; B. F, G. I. 20 pm; C, 13.3 pm; D. J, 26.6 pm; E, 28.5 pm; L, 25 pm.

GEODIVERSITAS • 1999 • 21 (3)

T4|g :

Palaeogene siliceous microfossils of Volga Région

Odontotrnpis carinata Grunow (1884) -

Homann 1991, pl. 27, iigs 5, 7; pl. 28, figs 1-3

[= Odontotropis danicm Dcbes — Fenner 1985:

734, pl. 14, fig- 11 (Fig. 71, J).

Odontotropis crtstata Grunow (1884) —

Homann 1991, pl. 29, figs 1-5.

Paralia crenulata (Grunow) Gleser stat. nov. —

Makarova 1992: 50, pl. 41, figs 1-8.

Paralia grunototi Gleser stat et nom. nov. -

Makarova 1992; 51, pl. 41, figs 9-11; pl- 42.

Paralia sulcata (Ehrenberg) Cleve (1884) -

Makarova 1992; 52, pl, 43.

Proboscia cretacea (Hajos & Stradner) Jordan

& Priddle, 1991: 56 1= Rhîzosolenia cretacea

Hajos & Stradner, 1975: 929, pl. 7, fig. 1;

pl. 31, figs 4-6. — Fenner 1991, pl- 1, figs 4-91-

Pseudopodosira westii (W. Smith) She.shukova

& Gleser, 1964, pl. 1. figs 4, 5.

Psettdopodosira sp. 2 sema Homann, 1991:

134, pl. 54, figs 9, 10.

Pseudostictodisciis anpilatns Grunow (1876) —

Fcnncr 1994, pl. 3, figs 12-17 (Fig. 70).

Pterotheca major ]o\ssé-, 1955: 101, pl. 6, fig. 2.

- Harwood 1988, fig.s 16, 18.

PyxîdicHla ferox (Greville) .Strelnikova &

Nikolaev - Makarova 1988: 41, pl. 23, figs 7. 8

(Fig.^GO.

Pyxidiciila moelleri (A. Schmidt) Strelnikova &

Nikolaev, 1986: 952 \=-Coscinodiscus moelleri A.

Schmidt - Homann 1991, pl. 10, figs 4-8

(Fig. 7A).

Pyxiducula sp. Common occurrence of different

Pyxidiciila is observed in the upper part of

Granoe Ukho section. Mosc of these belongs to

Pyxidicula tnrris (Greville & Arnort) Strelnikova

& Nikolaev, 1986 group and Pyxidicula corona

(Ehrenberg) Strelnikova & Nikolaev, 1986

group.

Rattrayella oatnaruensis (Grunow) De Ton!

(1896) — Homann 1991, pl. 33, figs 1-7

(Fig. 7C).

RiiW'ayella rotundata (Shibkova) Gleser, 1995,

pl. 1 , fig. 20. (Fig. 7B).

Rhaphoneis morsiana Grunow in Pantocsek

(1886-89) em, Homann 1991: 129, pl. 34,

figs 9-12.

Rhaphoneis simbirskiana Grunow in Pantocsek

(1886-89) - Proshkina-Lavrcnko 1974, pl. 15,

fig. 15 (Fig. 6A).

Rhîzosolenia hebetata Bailey (1856) — Homann

1991. pL 36, figs5, 11> 12.

Solium exsculptum Heiberg (1863) — Homann

1991. tf. 37, figs 1, 3, 5-7 f- Trinacria exsculpta

(Heiberg) Hust. — Mukhina 1976, pl. 2, fig. 7

(Fig. 4G).

Stellarima microtrias (Ehrenberg) Hasle àc

Sims, 1986: II, figs 18-27.

Thalassiosira sp. 1 sensu Thalassiosira ? sp. 1

sensu Fourtanier, 1991, pl. 1, fig. 12 [= Genus

and spccie indct. — Schrader & Fenner 1976,

pl. 33. fig. 7 (Fig. 6F)]. _

Thalassiosiropsis ivittiana (Pantocsek) Hasle,

Hasle Syversten, 1985, 89 f, Abb. 1-41. -

Homann 1991, pl. 37, figs 8-10 (Fig. 6j).

Tfdcejatiufft flos Ehrenberg (1885) - Homann

1991, pl. 44, figs 1, 2, 6 (Fig. 4J).

Triceratiiun heibergii sensu Gombos, 1977,

pl. 1, fig.s 1-12 (= Triceraiium caudatum Witt,

Proshkina-Lavrcnko, 1974, pl. 15, fig.] [=

Trinacria i7itiricata Gleser, 1995, pl. 1, fig. 4

(Fig.4K)l.

Triceratium kinken A. Schmidt (1874-1959) —

Prosh-kinâ-Lavrenko 1974, pl. 23, fig. 3.

Triceratium mirabile jousé in Proshkina-

Lavrcnko, 1949: 166, pl. 6, fig. 5 - Fenner 1991,

pl. 9, figs 7-10 (Fig. 4D).

Triceratiîim sparsipunctata Jousé, in

Proshkina-Lavtenkü 1949: 169, pl. 64, fig. 6

(Fig. 4F).

Trinacria veuiriculosa (A. Schmidt) Gleser, in

Proshkina-Lavrcnko 1974, pl. 18, fig. 12

(Eig. 41).

Trinacria excavata Heiberg (1863) — Homann

1991, pl. 46, figs 1-8; pl. 47, figs 1-6. (Fig. 4B,

E).^

Trinacria pileolus (Ehrenberg) Grunow (1884)

— Gombos 1977, pl. 37, figs 3, 4.

Trinacria regina Heiberg (1863) em. Homann

1991: 124, pl. 50, figs U7\ pl. 51, figs 1-7. -

Proshkina-Lavrcnko 1974, pl. 23, fig. 6

^Fig. 4H).

Trochosira spinosa Kitton (1871) - Homann

1991, pl. 17, figs 6-13.

GEODIVERSITAS • 1999 • 21 (3)

447

Khokhlova I. E. & Oreshkina T. V.

Fig. 7. — A. Pyxidicula moelleri (A. Schmidt) Strelnikova & Nikolaev. sample 58; B, RatirayeHa rotundata (Shibkova) Glaser

sample 79; C, Rattrayella oamaruensis (Grunow) De Toni, sample 87; D, Pseudostictodiscus angulatus Grunow, sample 74

E, Pyxidicula sp.. sample 58; F, Aulacodiscus schmidtii Witt, sample 74; G, Kentrodiscus fossilis Pantocsek, sample 94

H, Pterotheca sp., sample 100; I, J, Odontotropis carinata Grunow, sample 100; K, Aulacodiscus probabilis A. Schmidt, sample 88.

Scale bar: A, 14.2 pm; B-D, G. K, 20 pm; E, 40 pm; F, 13.3 pm; H-J, 26.6 pm.

GEODIVERSITAS • 1999

Fig. 8. — A'D. Naviculopsis constricta (Schuiz) Frengueüi; A. sample 74; B, sample 58; C, sample 67; D, sample 58; E, Naviculopsis

punctilia Perch-Nielsen. sample 67; F. Naviculopsis danica Perch-Nieisen, sample 67; G, Dictyocha precarentis Bukry, sample 88;

H, Corbisema hastata hastata (Lemmermann) Bukry. sample 108; l, Corbisema hastata globulata Bukry, sample 58; J, Corbisema

disymmetrica var. commuais Bukry, sample 109; K, L, Dictyocha elongata Gleser; K, sample 88; L, sample 95; M, N. Naviculopsis

robusta Deflandre; M, sample 74; N, sample 109. Scale bar: A-C, E-N, 20 pm; D, 26,6 pm.

GEODIVERSITAS • 1999 • 21 (3)

449

Khokhlova I. E. & Oreshkina T. V.

Xanthiopyxis s^. l-form 7 sensu Homann 1991,

pl. 57, figs 14, 15.

SILICOFLAGELLATES

Corbiseinn disymmetrica var. coinmunis Bukry,

1976: 891, pl. 1, figs 5-9. - Perch-Nielsen 1985,

fig. 11(8) [= Dictyocha navicula Ehrenberg,

Gleser 1966: 251, pl 9, figs 4, 5; texr-fig. 6(6)]

[= Corbisema naviculoidea (Frenguelli) Pcrch-

Nielsen, 1976: 33, fig. 7, 19, 22 (Fig. 8J)J.

Corbisema hastata hastata (Lcmmermann)

Bukry, 1976: 892, pl, 4, figs 9-16. — Perch-

Nielsen 1985, fig. 11 l22, 23) (Fig. 8H).

Corbisevia hastata globtdata Bukry, 1976: 892,

pl. 4, figs 7, 8 (Fig. 81),

Corbisema inerviis inermis (Lemmermann)

Bukry, 1976: 892, pJ. 5, figs 1-3.

Dictyocha elongata Gleser, 1960: 131, 132,

tabl. 1, pl. 2, figs 16-20. — Perch-Nielsen 1976.

fig. 2 (Fig. 8K. L).

Dictyocha fibula Ehrenberg (1839) — Perch-

Nielsen 1985. fig. 15 (17).

Dictyocha precarentis Bukry, 1976^894, pl. 6,

figs 6-13v pl. 7, figs 1-3 (Fig. 8G).

Naviculopsîs constricta (Schulz) Frenguelli,

(1940) — Perch-Nielsen 1985, figs 26 (6, 7)

(Fig. 8A-D).

Naviculopsis datiica Perch-Nielsen, 1976: 35,

figs 5, 6, 21. — Gleser 1995, pl. 1, fig. 27

(Fig. 8F).

Naviculopsis punctilia Perch-Nielsen, 1976: 36,

figs 26, 27; 1985, fig. 26 (33) (Fig. 8E).

Naviculopsis robusta Deflandrc (1950) - Gleser

1995, pl. l,fig. 29 (Fig. 8M, N).

RADIOLARIA

Anthocyrtoma (l) Jrizzeli Nishimura, 1992:

332, pl. 9, fig. 13, 14; pl. 13, fig. 8.

Botryometra (f) osha Kozlova, 1978: 95, 96,

pl. VI, fig. 9, 10; pl. XIX, fig. 3.

Buryella tetradica Foreman, 1973: 443, 8,

figs 4, 5; pl. 9, figs 13, 14. - Kozlova 1984,

pl. XII, fig, 16 1= Lithocampium sp. A - Riedcl &

Sanfilippo 1971, pl. 7, fig. 12],

Clathrocyclas elegam (Lipman, 1958) - Kozlova

1978. pl. 17, figs 1, 4, 5. — Kozlova 1990; 78,

pl. XII, fig. I4. - Petrushevskaya & Kozlova

1979, fig. 500 [= Theocorys sporta Kozlova in

Kozlova, Gorbqvetz 1966: 11, pl. 17, fig. 8.

Clathrocyclas exteusa Clark & Campbell, 1942:

85, pl 8, fig. 11. - Bjorklund 1977, pl. 21,

fig, 4, - Kozlova & Corboverz 1966, pk 21,

fig. 8. — Petrushevskaya &: Kozlova 1979: 131,

fig. 38b, 504.

Clathrocyclas lipmanae Kozlova, 1978: 121,

pl. 6, fig. 3, 6, pl. 17, fig. 12, pl. 19, fig. 8. -

Kozlova 1990: 78, pl. XII, fig. 21.

Clatln^ocyclas longispina C'Iark & Campbell,

1942- Kozlova 1978, pl. XVII.

Diplocyclas cornuta runjevae Kozlova, 1978:

124, pk VI, fig. 1 ,4, pk XJX, fig. 6.

DiplocycLts pseudobicorona pseudobicorona

Nishimura, 1992: 340, pk 4, figs 4-6, pk 13,

%• > 4 .

Larnacalpis (f) smili Middour-Kozlova 1978,

pk IX, figs 3, 5.

Lophophaemi curta Kozlova, 1978, pk V, figs 7,

8; pk XIX, fig. 4.

Peritiviator (?) dumitricae Nishimura, 1992:

328, pl. U %. 13-16, pk 11, fig.s 11,12.

Petalospyris fîscella (Kozlova) - Temtspyns fiscella

Kozlova in Kozlova & Gorbovetz 1966: 92,

tabl. XV, fig. 1 |- Hextispyyis sp. — Petrushe\^kaya

& Kozlova 1972, pl. 40, fig. 6| [= Hexaspyris fis-

celLi (feizlova) — Kozlova 1978; 89, pk VIII, fig. 6].

Petalospyris foveolata Ehrenberg 8c Kozlova,

1978: 89-90, pl. 6, fig. 8: pk 8, fig. 10; pk 19,

figs 9-13.

Petalospyris tmnidnla Kcïzlova in Kozlova &

Gorbovetz, 1966:97, pk Xy. figs 10, 11,

Phormocyrtis reticula (Kozlova) [= Theocorys

rcticiih Kozlova in Kozlova Gorbovetz, 1966:

110, pl. XVII, fig. 7]

Plectodiscus totchilinae Kozlova, 1984: 206-

207, pkX, fig. 13.

450

GEODIVERSITAS • 1999 • 21 (3)

Palaeogene siliceous microfossils of Volga Région

Spongasteriscus cruciferus Clark & Campbell,

1942 — Kozlova 1984, pl. X, fig. 16.

Spongodiscm americaniis Kozlova in Kozlova &

Gorbovetz, 1966, tabl. XIV, figs 1, 2. —

Sanfilippo & Riedel 1973: 524, pl. 27, fig. 11;

pl. 28, fig. 9 [= Spongodiscus americanus america-

nus Kozlova, 1978: 77, tabl. XIV, fig. 3].

Spongomelissa mima callosa Kozlova, 1978:

101, pl. XII, fig. 2; pl. XIX, fig. 2.

Spongomelissa numa numa Kozlova, 1978:

100, 101, pl. XII, figs 4, 5.

Spongomelissa (?) temaria Kozlova, 1978: 101,

102, pl. VIII, fig. 1; pl. XIX, fig. 1.

Spongotrochas alveatus Riedel & Sanfilippo in

Sanfilippo ôc Riedel, 1973: 525, pl. 13, figs 4, 5;

pl. 30, figs 3, 4. — Kozlova 1984, pl. XI, fig. 6.

Spongotrochas helioides (Cleve) - [= Spongo-

trochus sp. ajf. Trochodiscus helioides Cleve —

Kozlova 1978: 82, 83, pl. 16, fig. 6].

Spongotrochas nativus praecox Kozlova, 1978:

78, pl. 14, fig. 1.

Spongotrochas paciferas antiquas Kozlova,

1978, tabl. XVI, figs 4,5.

Spongotrochas puter Kozlova, 1978: 82, pl. 5,

fig. 10.

Thecosphaerella rotanda Borissenko, 1960:

222, pl. 1, fig. 3, pl. 3, figs 2, 3. - Sanfilippo &

Riedel 1973: 522, pl. 26, fig. 3 [= Thecosphaera

melitomma Kozlova in Kozlova & Gorbovetz

1966: 52. pl. VII, figs 7. 8].

Tripodiscinas sengilensis Kozlova, 1978: 104,

105, pl. V, figs 1-5; 1984; 207, 208, pl. XII, 20.

Tripodiscinas sibiricas Kozlova, 1978: 103,

104, pl. XII, fig. 3; 1984: 208, pl. XII, fig. 4 [=

Tripodiscinas tumulosa (Kozlova) - Petru-

shevskaya 1971, figs 33-V-VI] [= Tripodiscinum

sp. A - Petrushevskaya 1971, figs XI-XII].

Tripodiscinas trilobatus Kozlova, 1978, pl. X,

figs 4, 5.

GEODIVERSITAS • 1999 • 21 (3)

451

Eocene stratigraphy of key sections

of the Dnieper-Donets Dépréssion based

on calcareous and siliceous microplankton

Irina E. KHOKHLOVA, Eleonora P. RADIONOVA.

Vladimir N. BENIAMOVSKII & Ekaterina K. SHCHERBININA

Geological Institute, Russian Academy of Sciences,

Pyzhevsky per. 7, Moscow, 109017 (Russie)

khokhlova@ginran.msk.su

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K. 1999. —

Eocene stratigraphy of key sections of the Dnieper-Donets Dépréssion based on calca¬

reous and siliceous nnicroplankton, in Crasquin-Soleau S. & De Wever P. (eds), Peri-

Tethys: stratigraphie corrélations 3, Geodiversitas 21 (3) : 453-476

KEVWORDS

Dnieper-Donets Dépréssion,

radioiaria,

diatorns.

silicoflagellates,

foraminifera,

Eocene,

stratigraphy.

ABSTRACT

Radiolarian, diatom, nannoplankton, and foraminifer assemblages were stu-

died in detail in four key sections (Kantemirovka, Sergeevka, and 9540

Rudaevka, 5-93 Boguchar boreholes) of the souüi and central parts of the

Voronezh anticline area. The widespread middle Eocene sédiments lie uncor-

formably on maris and limestones of Upper Cretaceous âge. Thcy are mainly

composed by a transgressive-regressive succession of phosphoritic sands,

maris, and siliceous clays ot the Kiev Formation in the Ukraine (or Sergeevka

and Tishki formatioas in Russia) and by sandy clays and siliceous clays of the

lower part of the Khar'kov Formation in the Ukraine (or Kas’anovka

Formation in Russia). Lithologically, the cocval formations range from terri-

gcnous-carbonate to siliceous-carbonate. The âge of the formations has long

remained a point of discussion. Recent studies based on calcareous and, espe-

cially, siliceous microplankton allowed a direct corrélation of these .sections

with standard zonal scales.

GEODIVERSITAS • 1999 • 21 (3)

453

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

MOTS CLÉS

Dépression du Dniepr-Donets,

radiolaires,

diatomées,

silicofla^ellés.

loraminiftres,

Éocène,

stratigraphie.

RÉSUMÉ

Stratigraphie des coupes clvs de l’Eochte dans la dépression du Dniepr-Donets

fondée sur le microplancton calcaire et situeux.

Les assemblages de radiolaires, diatomées, nannoplancton et foraminifères

ont été étudiés en détail dans quatre séries clés (les coupes de Kaiitcmirovka

et Sergcevka et les forages 9540 Rudaevka et 5-93 Bogueliar) des parties

méridionale et centrale de la région de Tanticlinal de Voronezh. Les sédi¬

ments, largement rép.uidus, de TÉocène- moyen reposent en discontinuité sur

des marnes et calcaires du Crétacé supérieur. Ils sont principalement compo¬

sés d’une succes.sion transgression-régression de sables phosphatés, de marnes

et d’argiles siliceuses de la formation de Kiev en Ukiaine (ou les formations

de Sergee\'ka et T'ishki en Russie) et par des argiles sableuses et des argiles sili¬

ceuses dam la partie inforieure de la lormation de Kl^ar'kov en Ukraine (ou

de Kas'anovka en Russie). Lirhologiqucmcnr, les formations équivalentes

vont des carbonates terrigcncs auü carbonates siliceux Lagc des formations

est resté longtemps très di.scuté. Les études récentes* fondées .sur le micro-

plancton calcaire et surtout siliceux permettent des corrélations directes avec

les zones des échelles standart.

INTRODUCTION

The Palaeogene sédiments of the south-eastern

slope of the Voronezh anticline, which aiso repre-

sents the north-easi Bank of the Dnieper-Donets

Dépression (scc Radionova et al.^ this volume,

fig. 1), hâve been studied stratigraphically silice

the 1960s, when the lithostratigraphic scheme

was proposcd and usctl to subdividc thèse depo-

sits (Semenov 1965). *1 lie PaUcogcnc deposits of

the région represent a graduai tran.sition from

typical faciès of the Dnieper-Donets Ba.sin

(Ukrainian type of succession) to lacics of the

Volga-Don Région. In the western part ol the

area, a Ukrainian Utliostratigraphic schemc

(Makarenko et al, 1987) is used. The Palaeogene

of the marginal ea.st-northern areas of Dnieper-

Donets Basin is subdivided according to

Semenov (1965). In Volga-Don Région, the

scheme of Kurlaev (1968) is used (Fig. 1). This

faciès transition can be observed in sections stu-

died in rhe présent paper. The presence of both

calcareous and siliceous microplankfon in ail stu-

died sections allowed us to correlate rhe Eocene

part of ail llie sections.

The Palaeogene succession of the western

Kantemirovka and Sergeevka sections (Fig. 2) is

very similar to thar of the central part of

Dnieper-Donets Dépréssion and begiiis with

dark green and greyish grcen mica-glauconite

sands of Buchack Formation containing no

macro- or microfossils. Up to chc section lies rhe

Sergeevka Formation represenlcd by maris with

sandy and clayey interlayers it ihe base. The

superpo-s'ing Fishki Formation is coniposed by

sandy noiicarbonate clays. Both Sergeevka and

Tishki formations represent distinct transgressive-

regressive cycle and arc believed lo correspond to

the Kiev Formation of the LIkrainc, The overlap-

ping KasVan Formation, as a rule, begins with

sandy layer grading up to the section into sili-

ceous clays. The uppermost Kantemirovka

Formation is exposed in the Kantemirovka

Section only and is compo.scd of sandy deposits.

The Kas’yan and Kantemirovka formations

rcpre^ciu the second transgressive-rcgressivc cycle

and arc cocval co rhe Khar’kov Formation of the

LTtraine.

In rhe Boguchar Section, ihe Eocene formations

are composed t)f facie.s different from that of the

three western sections (Sei^eevka, Kantemirovka

and Rudaevka). The lowermost sedimemary

cycle includes lowermost Osinovo and Tchir

beds, represented by more terrigenous sédiments

454

GEODIVERSITAS • 1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donecs Dépréssion

M

Onieper-Donets

Dépréssion

(Makarenko étal.

1987)

Soulh«eastern

borderof

Voronezh

aniecline

(Semionov 1965)

Lower reaches

of Volga and

Don rivers

(^Kurlaev &

Akhlestina

1988)

T his pa pe r

H

1

c

O

Mezhigorka

E Fm.

O

LL

Kantemirovka

Fm,

Upper

Priabonian

>

O

«J Obukhovka

ë Fm.

Kasyan

F m.

Kante¬

mirovka

Fm.

K h a rko V

F m,

Eocene

c

ea

ET

O

Kiev Fm.

Tishki Fm.

Kuma Fm.

Kasyan Fm.

O

m

Tishki Fm.

Kiev F m.

•O

■O

C

cd

Sergeevska Fm,

Tchir beds

Sergeevka

Fm.

■U

_1

Osinovo Fm.

Fig. 1, — The Eocene lithostratigraphic scheme of the studied région.

than chose of Sergeevka Formation, and browni-

sh clays named Kuma Formation. The last for-

marion corresponds in its sedimentary

composition and stratigraphie position to the

Kuma Formation ofche Northern Cis-Caucasia.

Lithostratigraphical unies of souih-wcstern

Russia (Voronezh anricline) can be considered as

a reflection of the cransgressive-regressive succes¬

sion in the North Peri-Techys Région. A number

of problems arise when the issues concerning the

Palaeogene palaeogeography and detailed âge

corrélation are to be approached.

The first problem is the age span of the Kiev

“mari" and ifs corrélation with eastern sections.

The second problem lies in dctcrminlng the âge

of the siliceou.s units, i.e., the upper part of the

Kiev Formation and the lowcr part of Khar kov

Formadon, and in coirclating them with cocval

stratigraphie unies further east.

SAMPLES

Two sections — Kaniemirovka and Sergeevka —

and two boreholes — 5-93 Boguchar and 9540

Rudaevka - were sampled carefully during the

field trip to the Voronezh anricline area in July

1994. More than 100 samples were processed,

and in 79 of them microfossils were foiind

(Fig. 2A).

Methods

To stLidy siliceous niicro-organisms, each sampic

was placed into a 400 ml glass^ desegregated

mechanically» and chen hoiled for 15 minutes

with addicion of about 50 ml of 30% hydrogen

peroxide Each sample was soaked for

one hour with distillcd water, rinscd, and the

procedure was repeated undl the sctiling dme

becaine about 5 minutes for radiolarians. Slides

for radiolarian scudy were prepared on 24 X

24 ram cover glasses and mounted in Canada

halm on 24 X 80 mm glas.s slides. Samples for

diatom study were mounted on 18 X 18 glass

slides. Radiolarians were examined at X 400, and

diatoms, at X 1000.

For nannoplankton study, smcar slides from

liquid alcohol suspension were made with

Canada balm and examined at X 1000 with the

use of immersion oil.

GEODIVERSITAS • 1999 • 21 (3)

455

Eocene stratigraphy of the Dnieper-Donecs Dépréssion

B

C

cç

'c

O u:

Sergeevka

Section

Kantemirovka

Section

ô

Rudaevka

Borehole 9540

Boguchar

Borehole 5/93

Fig. 2. — A, corrélation of studied sections of the eastern slope of the Dnieper-Donets Dépréssion. N,, 2 « nannofossil assemblage;

F, foraminifera assemblage; radiolaria assemblage: D^.g, diatoms assemblage. B. samples number from the sections.

Foraminifers were washed with the use of sieves

and examined at X 25-30.

MICROPALEONTOLÜGICAL ANALYSIS

The corrélation of the foraminifera, nannofossil,

silicoflagellate, radiolaria, and diatom zonal

scales Liscd in chis papcr are shown in Figure 3.

Results of micropalaeontological study of sec¬

tions are shown in Figures 2, 3 and Tables 1 ro

13. Species were recorded as abundant (A) if

more than 15 specimens were présent in the

slide, as frequent (F) if 10-15 species were pré¬

sent, as common (C) if 3-9 specimens occurred

in the slide, and as rare (R) if 1-2 specimens were

found.

Sergeevka Seciion

Sergeevka Section, occupying the north-western-

GEODIVERSITAS • 1999 • 21 (3)

457

Khokhlova 1. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

most position among the studied sections, is very

similar ia litliologicd composition to the succes¬

sion ol the Dnicper-Donets Dépréssion. )t bcgins

with dark grecn and greyish grcen mica-glauconi-

tc sands oï the BuchaeJe Formation, which arc

barren ot macro- and microtossils. Up to the sec¬

tion, the Kiev Formation represented by maris

with sandy and clayey beds 7 m in thickness lies.

These are ovetlain by the Kiev Formation: maris

with sandy and clay beds 7 m thick. The upper

part of ihc Kiev formation is composcd of sândy

non-carbonatc clays, 5 m in thickness. The lowcr

part of the formation is the samc as the

Sergeevkâ Formation of .Semenov (1965) sche-

me, and the uppex part of the KJe^^ Formation is

équivalent to Semenov (1965) Tishki Formation.

The lower part of the Khar'kov Formation

(Kasyan Formation of Semenov (1965) scheme)

begins with sandy layer passing upsection into

siliceous clays, l'he exposed thickness of these

sédiments, is about 5 m, Thcy arc unconformably

overlapped by sands of Neogene (?) âge.

NannofossUs

At the base of the Sergeevkâ Formation in a

sandy unit, a poor nannofossil assemblage (N:

range of nannofossil assemblage in Figs 2, 3) of

the middlc Eocene âge is présent.

A rather abundant nannofossil association (Ni)

including Cycliiargf^ltthus florieiarnis (Roth &C

Hay in May et ni 1967) Biikry, Discoaster hnrba-

diensis Tan, D. rjffdifcr (Bramlcie & Riedel)

Bukry, D. strictus Stradner, D. wctnmelensts

Achuthan 6c Stradner, Retiaihfene^trn dictyodn

(Deflandre in DcBandre & Fcri), Stradner in

Strander 6c Edwards, etc, was found in maris of

the Sergeevkâ Formation (Table l). Nevcrthcless,

the absence of any boundary 2 onal markets docs

not allow us to judge whether it belongs to rhe

uppermost C'PI3 Nannotetrinn quadrnta or

lowermost CP 14 Retiadojhmtrn lonhilica zones.

Foraminifern

In the maris ol the Sergeevkâ Formation, an

abundant and well-prcservcd benthic foraniinile-

ra association (F: range ot foraminifera assembla¬

ge in Figs 2, 3) contains Spiroplectammina

pishvanovae A. V. Furssenko 6>L K. B. Furssenko,

Clavulinoides sezaboi (Hantkcn), Vagimdinopsis

deeorntn (Reuss), Cibicidoides biumbonatus (A. V.

Furssenko 6c K. B. Furssenko). Uvigerina spino-

coitata Cushman & Jarvis (= Uopkimia hykovae

ukrainien Kraeva), U. cosullnta Morozova,

Bîdimina madlentn Cushman àC Parker. B, cooki

Cushman (Table 2). This assemblage can be rela-

ted to the middic-upper [.utetian Pseudo-

cldvulinâ subhotinae-Uvigerirui spinocostata-

Bolivinn caukd régional zone (Naidin et al. 1994;

Radionova er j/. 1994).

Radiolxtrin

The most ancient radiolarian assemblage (R:

range of radiolarian assemblage in Figs 2, 3) was

found in the middle part of the maris ot the

Sergeevkâ Formation (Table 3) and is represented

by Clnthrocyclas niininta Clark & Campbell,

Pleliüdisius helinsterisius Clark 6c Campbell,

H. dupla Kozlova, Üpongomclissa sp. A,

Lithornelissa sp. A, CalaycLu semipolita Clark &

Campbell, ibteosphaern minor Campbell &

Clark, Siyhnrochm radinms Lipman, Theocyrtis

lidm Clark 6c Campbell. Taxonomical composi¬

tion of fhe .is.sociarion c.innot coivstrain the âge

of sédiments more prccisely rhan middlc Eocene.

Upsection, nKliolaria are found only in siliceous

clays of Kas’ydnovka Formation assemblage (R5)

is taxonomically diversified and abundant,

containing Stylodictyn irregulnris Vinassa,

llcliodiscas heliasteriscus Clark 6c Campbell,

lleterosc^tiwv formosuni Tochilina, II. tschuenkoi

Lipman, Liihomtlif.^a sp B> Meliitosphaera

magnopnriihsn Nakaseko, Hetiodheus fragilis

Tochilina, bf. testntus Ko'àowx, ''Loplmyrtis *sinit-

zinr Lipman, Clathrocytlas extensa viultipUcata

(Clark 6c Campbell), Tripodisànus kaptarenkoi

Gorbunav. T. aff. tribrarhintus Gorbunov,

Theocyrtis lithos Clark & Campbell, and

Theocyrtis andriashein Petrushevskaya. It belongs

to the Theocyrtis andriashevi régional zone.

Diaiorns

In the lower part ot the Sctgccvka Formation

(Table 4), a typical Kiev diatoni assemblage with

Peponia harhadensh Grcvillc (Dl) (D: range of

diatom .isscmhlagc in Figs 2. 3) was tound.

Commun tava include Paralia oamaniensis

(Grove 6c Stuart) Gicler — index-specic^ of lhe

zone of the same name of the local scheme of

458

GEODIVERSITAS * 1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donets Dépréssion

.c

O

Q.

LU

Stage

Planklonic

foramindera

zonation

(Boii&Saiiideis

1985)

Crimea-CaucasLis

plaiklonic^ifafninrfBra

zcoalacale

(Anonymou5l909)

Nanoofûssl zorel

scale

(Okada&BuKiy

19001

zonal

xale

(BuftiyiOBI)

R(

radiolarians

(Koziova 1990)

sgional zonal scales

I diatoms

I Glezer 1989 thispaper

pper

P15

Globigerapsis

rropfcalis

CP15

ChiasmolUhüS

oamaruensis

Corbisema

apiculata

Theocyrtis

andriasheva

R5

Paralia

LU

Z

LU

oamaruensis

Z

Globtgenna

CPl4b

Discoaster

saipanensts

Ü

Q

Z

P14

turkmenica

Dictyocha

Ethniosphara

polysi^honia

layers with

LU

middle

O

1 —

Hantkenina

atabamensis

CP148

hexacantha

Brightwellia

imperfecta

D2-D2A

cc

<

CD

P13

Discoastet

bifax

Cytophormis

alta

P3

LUTETIAN

P12

Acarinina

rotundimarginatê,

CP13

Nannotetrina

quadrata

Navicutopsis

foliaceae

Heliodiscus

quadmtus

R2

Pyxilla

oligocenica

var. tenue

layers with

Peponia

barbadensis

DI

Fig. 3. — The corrélation of the foraminKera. nannofossil, silicoflagellate, radlolaria and diatom zonal scales.

Glezer (1979) — and Cristodiscus (Coscinodiscm)

succinctus (Shcshukova & Gleser) Gleser

Olshtinskaya» date index-species of the boréal

zonal scheme of Strelnikova (1992). Peponia bar-

badenüs Greville, index-spedes of rhe proposed

régional schemc (Radionova 1996) occurs rarely.

According lo Glezers (1979) local diarom sche-

me, ihe Paralin oaniaruensis zone is relared to ihe

Upper Eocene. and according ro Strelnikova

( 1992) boréal scheme, the Coscinodiscus succinc-

tiis zone bclongs to uppcrmoüt Lutetian-lower

Barconian. Layers wlrh Peponia harhadense

Greville are considered as upper Lutetian. The

association includes pelagic specics Pyxidivula

joynsonii (A. Schmidt) Strelnikovn & Nikolaev,

P charkoviana (Jouse) Strelnikova & Nikolaev,

Crnspcdodiscus moclleri A. Sclintidt, and a num-

ber of ncritic species. In Khar’kov (Kas'yanovka)

Formation, a diarom assemblage with

Eripphwellia imperfecta ]oms£. (D2) bccomcs more

abundanr. Besides, Mehsini arehittcLuralis Brun

(Schmidt et ai) and Pyxilla prolongata Brun are

comnion. l’he Coscinodiscus group becomes

more diversificd (C decmeenoides ]ousér C. bul-

liens Schmidt, C oculusiridis Ehrenberg), as well

as the Hetiiiaulus group (//. polymorphtis var.

charkovinnus Jousé, H. tschestnovji Pantoaek). In

the upper p.ïrt of the BrighwcJliâ imperfècca (?)

unit, Cosmiodiscus breviradiatus Gleser &

Olshtinskaya and Pseudotriceratiuni chenevieri

(Meistner) Gleser, appear. Index-species Brighi-

wellia imperfecta Jousé, covering a part of the

Bartonian stratigraphie interval of distribution,

allows determining the stratigraphie range of the

Kas’yanovka Formation.

ICantemirovka Section

The lower part of Scrgeevka Formation (Fig. 2), a

sandstonc layer 1.5 m thick with phosphorite

nodules, lies on chc Upper Cretaceous limestones.

Up CO the section is a unit of gtev maris and car¬

bonate clays 3-4 m thick. The upper part of the

Scrgeevka Formation is represented by non-carbo¬

nate clays of undetennined thickness. The Tishki

Formation lies una^nformably on the Sergeevka

Formation and is composcd of non-carbonate

clays 4-5 m thick, with glauconite at the base and

siliceous in the upper part. Fhe Kas’yanovka

Formation is represented by intercalations of red-

dish-yellowish gaize. breccia-like argiljtcs, and

glauconite sandstoties 4 m thick. Sands and sand-

stones of the Kantemirovka Formation overlap

rhese sédiments unconformably.

Namio/hssils

An abundant and diversified nannofossil assem¬

blage was obrained from ihc maris of rhe

Sergeevka Formation (NI) (Fig. 2). This assem¬

blage includes, among otliers, the t)^picaJ specics

of the CP 13 Nannotetrina qnadrata zone:

Nannotetrhut cristata (Martini) Perch-Niclscn,

Discoasier stnevus Stradner, Dictyococcites onusius

Perch-Nielsen (Table 5).

GEODIVERSITAS • 1999 • 21 (3)

459

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

In the uppermost part of che section, i.e. in car¬

bonate beds within the sandy Kantemirovka

Formation, a very poor and possibly reworked

nannofossil assemblage of Bartonian âge was

found.

Foraminifera

In the lower part of the Sergeevka Formation

maris, the abundant and diversified planktonic

foraminifera assemblage (F) was found (Table 6).

The mosr abundant are: Subbotina mrcmcnka

(Khalilov), 5. bowerl (Bolli), Globtgerinatheka

index (Finlay), Aenrinina afF rugosoaculeata

Subbotina. The assemblage can be related to the

upper part of the Acariniful rotnvdimarginata

(s.l.) zone of rhe Crimca-Caucasus schemc (beds

wirh Globigerinntheka index^ Beniamovskii 1995).

Benthic foraminifera are represenred by

Pseiidoclaviilina mbhotinne Nikitina, Vagwu-

linopsis decorata (Rcuss), Gyroidina soldant

(d’Orbigny), sculptilis Cushman,

B. cookî Cushman, Vvigvrina spinocostdla

Cushman & Jarvis, U. pygtneii d'Orbigny, V. cos-

iellata Morozova. Thcy arc related to the middle-

late Luretian Pseudoclitvulina subbotlniîe'

üvigerina spinocostdtU'Bolivina coukei régional

zone. Most of che spccies of the assemblages can

be traced in the European palaeobiogeographical

area from Belgium to the west parc of

Kazakhstan.

Radiolaria

In rhe lower pari of the Tishki Formation, rhe

radiolarian assemblage (R3) is taxonomically

poor, represented by Cyrtophormis alta Mok-

syakova. Cdathrocyclus utiwanii Bjorkiund bc

Kellogg, and Uthoinelîssa sp. A, fiable 7) and

most likely bclongs co the Cynophormis alta

régional zone (Kozlova 1990).

Upsection in upperrnost part of che Tishki

Formation and lowermost part ol che Kas'yanov-

ka Formation (the boundary between them is

not determined prcciscly in the section), radiola-

ria become more diversified (R4); Lithonielissa

sp. A., Heliodiscus heliasteriscus Clark &

Campbell, H. zonatnm (Lipman), H. fragilis

To c h i 1 i n a, Me lit tosp hue ra m agn o par ut o sa

Nakaseko, Calocyclas semipolita Clark bc

Campbell, Tripodiscinus kaptarenkoe Gorbunov,

Clathrocyclas extensa nmltiplicata (Clark &

Campbell), "Lophovynis^ sinïtzini Lipman,

Rathropyramis aneotos (Clark & Cambell),

Calocyclas asperum Ehrenberg, Hexacontnim aff

pacbydtrmum Jorgensen, Stylodyctya hastata

Ehrenberg. 5. tnegulans (Vinassa), Tnpilidium

ctavipes Bjorkiund, Theocyrîts lithos Clark &

Campbell, etc. Lasdy, in siliceous cUyey maris of

the Kasyanovka Fenmation, the assemblage of

Theocyrüs andriashevr régional zone (R5) is scen

and includes besides a number of species known

from R4 assemblage, l.ithelius foremanae

Sanfilippo ÔC Riedcl, Stylosphaern balbis

(Sanlllippo & Ricdel), Lithomelissa sp. B,

Heterosestenm forrnosum Tochilina, H. tschimxkoi

Lipman, and Theocyrüs andriashevi Petrushev-

skaya.

Diatotns and Silicoflagellates

l’he diatom assemblage obtained from the upper

part of the Tishki and Kas'yanovka formations is

similar to che D2 association from dic Sergeevka

Section, althougli it is not so diversified (Table 8).

Important is the présence of Cosmiodisensm hrevF

radiatas Gleser & Ol.shiiuskaya, and Bti^ttvcllia

coronata (Brightwcll) Ralfs in Fritchard, in the

lower Kas'yanovka Formation and the appearance

of Trkeratiuni ungukul/ttîan Greville, in the upper

part of chc saine formation.

9540 Rudaevka borehole

Whire chalk unit 3 m in thickness is correlated

to the Sergeevka Formation (Fig. 2), h is superse-

ded by aliernating maris and carbonate clays 6 m

ihick. 4‘he upper part of the Sergeevka

Formation is coinposcd of aliernating carbonate

and non-ciubonate clays The total thickness of

the Sergeevka Formation is 13 m Ar rhe base of

the Tishki Formation, a layer of glauconite sand

up to 0.5 m thick can be iraccd. The overlying

unit is represented by intercalations of clayey

mudscones, opoka sandstones and clays, some-

times with thin beds of carbonate clays-, The

thickness of this formation is 14 m. At the base

of the Kas’yanovka Formation, a 0.5 m*thick

glauconite sandy layer is présent, ovcrlapped by

clayey diatomites 4 m in thickness, The upper-

most 8 m of the section are represented by sands

of the Poltava Formation.

460

GEODiVERSITAS • 1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donets Dépréssion

NannofôssHs

A nannofossii assemblage related ro CP13-CP14

nannoplankton zones boundary interval (N) was

found at the base of the marly section of the

Scrgccvka formation. The assemblage is not so

rich as in Kan terni rovka Section, but scems to be

of the samc age bccause of the presence of

Rhabdosphaera glndius Locker, which is zonal

marker of the CPI3 Nunnotetrina quadntta zone

top boundar)'^ (Tiiblc 9).

Foraminifera

Foraminifera in borehole 9540 occur rarely. For

this reason, siliceous microfossils are the primary

basis for stratigraphie subdivision of the section.

Ritdiolitna

A radiolarian assemblage ('Fable 10) represented

by Stylodyctya hastaUi Ehrenberg, Thecosphaera

minor (Clark ôc Campbell), Heliodiscus heliaste-

rlsctis Clark & CampbeIK C.lathrocyclm pr'mcipi

principi Clark &: Campbell, Stylotrochns sp., and

Lithomelissa sp. A was found in ihc lowcr part of

the Scrgccvka Formation maris. The assemblage

is not taxonomically diversified. AH the specics

arc known from the Keresea and Kuma forma¬

tions of Southern Cis-Caucasia and Central Asia

(Moks}^akova 1972). ’Fhe age cannot bc constrai-

ned more precisely than iipper Luthetian-

Bartonian. The upper part of the sa me formation

contains a more diversified assemblage {R2),

represented by Heltodiscui hexasierhcus CHark &

Campbell, Hexacomittntpachydermurn jorgensen,

Petalospyris aff. duhia Clark & Campbell,

Clathrocyclas extensa Clark &: Campbell,

l'heocorys reticuln Ko'/Jova, Hetewsesti'nrn fornm-

sum Tochilina, H. ticbuenkoi Lipman, Stylo-

sphaera coronatn tnevis Ehrenberg, Tripodiscinns

turnulosus (Kozlova), Xtphospira occllata (Ehren¬

berg), Thecosphaera californien Clark ôr (Camp¬

bell and Lithomelissa affi haeckeli Butschli. Fhc

composition ol ilic association is close to tlic

Kuma Formation, the assemblage not including

only species of the généra Tripodiscinus and

Heterosestmm.

Up to the section in claycy maris of ihe Tishki

Formation, an assemblage coniainiag abundant

Cenospbaern rnitgarzi Lipman and rare

Heterosestrum TschueJikoi Lipman, Peripyramis cir-

cumtexta Haeckcl, and Cyrtophorrnis alta

Moksyakova was found. The présence of the lut¬

ter specics together with Heterosestrum ischuaikoi

Lipman, in spire of the poor taxonomical com¬

position allows cortclating this association to the

Cyrtophorrnis alta (R3) rcgional radiolarian zone.

Highei up to the .section in clays ol the samc fox-

marion, the following radiolarian assemblage

(R4) is présent: Cenosphnern mitgarzi Lipman,

Stylodyctya irregularis (Vinassa), S. hastatn

Ehrenberg. Heterosestrum formosurn Tochilina

and Theocorys reticula Kozlova. Thèse taxa arc

not indicative but the stratigraphical position of

the assemblage in the section suggests that ir can

be related approximarely to the Fahniusphaem

polysiphonia régional zone.

Up to the .section in siliceous clay.s of the

Kas’yanovka Formation, the radiolarian assem¬

blage (R5) bccomes more diversified and abon¬

da n t : Cenosphaera mIcroporn^ Stylodyctya

irregulfirii (Vinassa), S. hastatn (Ehrenberg),

Heliodiscus zoaatus Tochilina, Heterosestrum for-

mosum Tochilina, LUhelius Theocynis andria-

shevi Petrushevskaya, Calocyclas senùpolita Clark

Campbell and Lithomelissa sp. B. This as.sem-

blagc most probably belongs to the Theocynis

andriashevf régional zone.

Diatoms and Silicoflagellates

Diatoms werc found at the base of the mari unit

of the Sergeevka Formation and in noncarbonate

clays in ihc upper pan of ihc same Formation.

’Fhe a-ssemblage is rather poor (Dl) (Table 11),

Besides, species known from the Karnemirovka

and Sergeevka sections: CristodUcus duplex Gleser

& CMshrinskaya and Cnscinodiscus aff. tenerrimus

Jou.sé, and silicoflagellate.s Dietyoïha pentagona

(Schulz) Bukry & Foster, and Nnviculopsis folht-

ceae Detlandrc can be noted. In the lowcr part of

Tishki Formation, a poor diatom assemblage

conraining neritic Paralin sulcata (Ehrenberg)

CIcvc. Pseudopodosira hynltnu Jousc and

Aulneodisius excniuitus A. Schmidt was found.

Among pciagic species, Costinodisms obscurus var.

cancaous Cileser in Diatomovye vodorosly SSSR,

dominâtes. In the upper pan of ihe Tishki

Forniarion, ibe diatom flora bccomes more

diversified. More reprcseiuarives of the

Pyxidicula genus [P. moelleri (A. Schmidt)

GEODIVERSITAS • 1999 • 21 (3}

461

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

Strelnikova &C Nikolacv, R grunowii (Grovc &C

Stuart) SrtcJnikova Sc Nikolacv, ./? Joynsonii (A.

Schmidt) Srrelnikova Ôc Nikolacv, P. charkoviana

(Jousé), Strelnikova & Nikolacv), Craspedodistus

oblongus (Gfcvillc) Hanna and Coscinodisctts aff.

marginatus Ehrenberg] appear. Large diatom cells

dominatc along with unusually looking spéci¬

mens ol Meloiira arvhitecturalis Brun (Schmidt et

al.) which are up to 60-7B mm. in diameter. The

disappearance of Craspedûd/snys oblongus

(Greville) Hanna takes place in the upper part of

the Barronian. The présence of tins typical spe-

cies déterminés the âge of the upper part of the

Tishki Formation as the Barionian.

The assemblage of die Kas’yanovka Formation

includes common species of D2 assemblage. In

the uppermosr part of rhe formation (deprh

32 m), the abundance and diversity of silico-

flagellates increases. Common are typical

Bartonian taxa such as Nnviculopsis foliaceae

Dedandre, N. Piordtea Bukry, Distephanus crus

(Ehrenberg) Haeckel, Dictyocha spbwsa (Deflan-

dre) Glezer D. deflandrei Franguelli, Corbisema

hastata globulata Bukry, C htermis Lemm.

5'93 Boguchar. iu.irkhi^m-

The lithostratigraphic subdivision of this section is

made accordlng to the sclicmc ol Kurlacv &

Akhlestina (1988) fut the Khoper monocline. The

Veshenka Formation (Fig. 2), composed by sandy

opokas 5 m thick, lies on the Llppcr Cretaceous

sédiments. The Osinovo beds overlie them uncon-

formably. They are represeneed by ligJit grey opo¬

kas with phosphorite nodules al the base,

intercalatcd with sandstoncs. l'heir rhickness is

6 m. The Fehirsk)' beds consist of strong quarr-

zites 5,2 m thick, and upsection ot Hiie-graincd

glauconitc sands -with rare beds ot calcarcous clays.

Their thickness is 18 m. The Kuma Formation

lies on sands and is represenied by greenish lovv-

carbonate opokas 2 m thick, lurning up to the

section inio brownish non-calcareous clays. The

upper part of the formation is composed by light

opokas passing înto opoka sandsrones. The total

thickness of rhe formation is 20 m.

Nannofimib

The rarher poor nannofossil assemblage with rare

Chiasmolithus grandis (Bramietee & Riedel)

Radomski, C rnodestus Perch-Nielsen, C solitm

(Bramlctrc Sullivan) Locker, Discoaster barba-

diensis Tan, D. nodifvr (Bramleiter & Riedel)

Hukrv', Neococcolithm duhius (Deflandre) Black,

Reticîdofenestra diayodyî (Deflandre in Deflandre

& Fert) Siradner in Siradner & Edwards,

R. umbilicHs (Levin) Martini & Rir/kovski.

Coccolithus forrnosus (Kainprner) Wise found in

siliceous maris withiii a sandy unit fonncriy

considered as a part of Buchack (?) Formauon,

but this association can be considered as the

uppermost part of the Lutetian CP 13 Nanno-

tetrina quadraui zone or the lowermost Bartonian

CPI4a Discoasier bifâx subzone.

Radiolaria

A radiolarian assemblage (Table 12) obtained

from che base of Osinovo beds contains

Claîhrocyclai mintma Lipman, Hehodiscus hclia-

stenscus Clark & Campbell, H- dupla Kozlova,

Spongomelissn sp. A, Uthomelissa sp. A,

Thecosphaera minor Campbell ^ Clark,

Spongotrocfms radiatits l.ipmati, Stylndyctya irre-

gularis (Vin.issa), and Themyrtrs lithos Campbell

Ôc Clark. The âge of the assemblage i.s lentarively

thought to be the middle Eocene, and not youn-

ger rhaii upper Lutetian.

Dp to the section in siliceous clays and maris of

Kuma Formation, the abuiidant radiolarian

assemblages of the Cyrtopborrnis alta-

Ethrnosplutent polysiphonia (R3-R4j régional

zones werc found. The association contains

Hexavontitim paebyderrnum jorgensen, Stylo-

sphaera coronaîa coronata Ehrenberg, Lithelius

spiralis Lipman, Bathropymrnis nnoetus (Clark &

Campbell). Clathrocyclns xahvanii Bjorklund Ôc

Kellogg. Cenospbaera mstgurzi Lipman, Theocyrtis

lithos Clark ôi Campbell. Cyrtophormh alta

Moksyakova, Artubotrys norvegieusis Bjt7rklund 6c

Kellogg. Theocûtys mienta Kozlova, Lithomelissa

sti^ Bueschli, Tripodisçintis tribrachiatm Kozlova,

77 kapfitrenkoi Gorbunov, and several other taxa.

The youngest radiolarian assemblage of the

Tbeotyrtis undriushevi régional zone (R5) was

obtained from siliceous clays of Kuma

Formation. It is abundani, well-preserved, and

contains I(exaconthttn pachydernium Kozlova,

Heterosestrum shabalkini Lipman, Thecosphaera

minor Campbell & Clark, Tripodiscinus tribra-

462

GEOOIVERSITAS • 1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donets Dépréssion

chiatus Koziova, Theatyrtis andriasbevi l^etrushev-

skaya, llaliomma immensa Kozlova, Calocyclas

asperum Ehrenberg and Rhodospyris donensis

Zagorodnuk.

Diatoms and silkoflagellates,

At the base of the Osinovo beds the following

diarom association was fnund; Paralia oamaruen-

sis (Grove & Stuart) GIcser, Cristodiscus

{Coscinidiscus) succinctiu (Sheshukova Glcscr)

Gleser ôd OLshtlnskaya, Hemiaulus potymorphus

var. charkovianiis (Sheshukova & Gleser) Gleser

& Olshtinskaya, plus Coschiodiscus obsurcin var.

concûvus Gleser in Diatomovye s^odorosly SSSR,

C. astéroïdes Truan hi Witt, C. bullïens A.

Sdimidt, C decrescenoides Jousé, C oculusiridis

Elircnbcrg, Brightweilut sp., Hemiaulus polycysii-

noTnm Ehrenberg, Afelosira Brun (Schmidt et

al.)^ PyxidicuLt alf. moelleri A. Schmidt and

P. charkoviana (^Jouse), Silicoflagcllares are. tepre-

sented by Naviculopsis nordica hyatina Bukry,

Mesoi'ena concava Pcrch*Nielsen, M. apiculata

Schuiz and Dktyocha venzoi Morlotci & Rio. Kcy

specics of this assemblage arc the samc as those of

the DI association of ihc three oihcr sections.

The association bclong.s to the upper Lurerian.

In the lower part of Kuma Formation the diatom

association (Table 13) issiniilar to the D2 assem¬

blage from 9540 Rudaevka borehole, and in the

niiddle part of ilie Kuma Formation the same

silicoflagellaie assemblage was tound. The rrend

of changes in diatom and silicoflagellate compo¬

sition is similar bodi in the 9540 Rudaevka bore-

hole and m the 5-93 Boguchar borehole. Ai the

17.8 m level silicodagellates dominacev but

upsection rhey are replaced by siliceous sponges.

Discussion

In the eastern part of Dnieper-Donets Dépréssion

(the area of Transition to Vc>lga-Don Région) the

fàcics change of Eocene sédiments is so dramaric

that one needs ro use three different lirhosrratigra-

phic schemes (Fig. 1) from nonh-we.st to south-

easi to .subdivide the Eocene deposits. These

schemes (for Ukraine, Vorone/h antecline, and the

Volga-Don Région) arc not sufficicntly corrclatcd

yet. In rhe eastern part of study région, some

lithostratigtaphic subdivisions of the northern

Caucasus scheme are used. That gives us a reason

to suggest a lithostratigtaphic and microplankto-

nic corrélation for the Crimea-Caucasus area and

the Dnieper-Donets Dépréssion, because ail the

studied sections showed similar sedimentary cycli-

ciries, and rheir formations can he dared and cor-

relared on the basîs of calcareous microlossils in

the lower part of sections and on siliceous micro-

fossils in rhe upper pan.

In the Crimea-Caucasus area, the lower middle

Eocene (Lutetian) sédiments arc represented by

maris and limestones of Keresta Formation. Up

to the section, Kuma Formation composed by

carbonatic clays rich in organic matter lies with

érosion in a number of localities. The following

changes in calcareous microplankton assemblages

occLir through tbc Keresta-Kuma boundary. Fhc

naiinofbssil assemblages of Keresta Formation are

very rich ail over chc area, and chc CPI 3

Namiotetrina epuidrata zone (Fig. 3) and ail three

subzoncs (CP 13a, CP 13b, and CP 13c) of nan-

notüssil standard zonal scale (OLada & Bukr}^

!98()) can be established. The top of Keresta

Formation is marked by disappearance of

Nannoteirina cfuadrata (Branileiic & Sullivan)

Bukry, N. cmiatu (Martini) Perch-Nielcn (1971),

Discoaster gemmifer Stradner. D. rnartinii

Srradner. No new .species appear at rhe base of

Kuma Formation. The CPl4 Reticulofenestra

umbilicn zone stands ont among the deep océan

sédiments owing to rhe Discottster bifax Bukry

appearance. lu ail studied sections of the South

of tlie Foimer USSR, ihi.s species appears wiihiit

CP 13b Chiasmolithus gigas sub/one* i.e., much

carlicr than in DSDP slcesi wherc the zonal scalc

of Okada ik Bukry (1980) was established.

Recenrly, its appearance was recorded within

Lutetian deposits of Parisian Basin and

Hampshire (Aubri 1983). Hence> this species

cannot be used as a zonal market in epicontinen-

tal basins. A few meters ahove rhe Kuma Forma¬

tion s bortom, characterisric species of CPH

zone gradually appear. These changes in nanno-

fossil assemblages led us to place the CP 13/CP 14

zone boundary along the Keresra-Kuma bounda-

ry because in spite of the .ib.sence of the rraditio-

nal zonal market, thèse zonc.s arc distinguished

by the full spcctriim of the assemblage.

The changes in planktunic toraminifera assem¬

blages proceed in a similar way. At the top of

GEODIVERSITAS • 1999 • 21 (3)

463

Khokhlova 1. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

Keresta Formation, such peculiar species as

Subbotina frontosa Subbotina. S. subtrilnadi-

noides (Khalilov), Acnriniiuz hullhranki Bolli,

Globigcrinathekn subconglohata (Khalilov iti

Shutzkaya). ^7. /Wt’v (Finlay) (Actirinhm rolundi-

marginata zone ot the Crimea-Cnucasus zonal

scale are presenr - beds wirh G. siibconglubitut-

G, indey^. The foraminiteral assemblage ol Kurria

Formation is composed by T^antkcnina nlabit-

mensis Cushman, Subhotina aserbaidjanica

(Khalilov) and other spccics. Thcn, rhe

Acarininn rotundimdrgiruita-Hantkenina alaba-

mensis zone boundary is cstablished mostJy by

the disappcarancc ol the characteristic species of

the First zone and corresponds with Keresta-

Kuma lomiadons boundary.

Far co the north, the Kuma Formation sédiments

onlap the sédiments corresponding to the

Keresta Formation with pronounced érosion.

The siliccous plankcon cornes into play along

with the calcarcous microfossils. The corrélation

of radiolarian and diatom zonal scales with chat

of foraminifera and nannofossils were made in

the sections of the norihcrn Feri-Caspian

(KhokJilova 19%; Radionova 1996). The corres-

pondence of ihc radiolarian Heliodiscus quadmtus

zone (R2) to the foratninifcral Acnrlnina rotundi-

marginatd zone, and Cytophorynh alta (R3),

Ethrnosph/iem polysiphonin (R4) to the fbramini-

ferai Hantketnna alabamer/sh and Glohorotalia

turcmenua zones is sliown.

In ail sTudied sections ol Dniepcr-Doncts

Dépréssion the same zonal succession was traccd.

The Heliodisais quadmtus (R2) zone assemblage

is recorded within the lowermost part of ail four

sections, i.e., wirhin Sergeevka Formation and

Tchir beds. The lollowing rhree zonçs (R3-R5)

are escablishcd wirhin rhe upperrnost part ol

Tishki and Kas'yan formations. This suggests a

corrélation of rhese lormations with Kuma

Formation of rhe .South of the Former USSR.

It is commun knowledge chat diatom assemblage

ol the Kiev and Kharkov lormations ol Ukraine

was proposcd as Pamlia ihimantmsis zone (Gle/er

et ai 1965). but boundary markets were noi

represented, so that even now'adav's under doser

examinaiion it is hard co cstablish the boundaries

of this zone. In ail studied sections two intcivals

with abundant diatoms separated by sédiment

intcrval of variable thickness withour diatoms

were found. Ficncc, we record not zones, but

layets with Peponia /w/w/e/wir Greville (Dl) and

layers with Bn^stxvellia imperfecut^y^sssé (or Coimo-

discus brevimdifUus Q\iyi^x ^ OLsIuinskaya) (D2),

Beds with Peponia barbadense Greville, corres¬

ponding lo the “Kiev" Formation or irs corre-

laies, correlatc with the upper Lutherian, and

beds with BrightioelUa iwperfecta Jousév corres¬

ponding to the lower parc of the “Khar’kov”

Fotmarion, with the Barconian. Of the diatoms,

Peponia barbademis Greville is rcscncced to rhe

Lurhetian, Craspedndheus oblongtts (Greville)

Haima disappeats in the tipper part of the

Bartoiiian (Fcnncr 1985). and Brighîwellia

imperfecta is restricted co the second half of the

middie Eocenc (Fenner 1985). Silicollagellates

manifest the disappearance of Dktyocba spinosa

(Deflandre) Gleser (in the Sergeevka Formation)

and appearance ol DieCyocha bexacarnha Schuiz

(in iKe Kas'yanpvka Formation), or clse,

Naviadopsis foliaceaeiDictyocha hexacantha zone

boundary correlaies with the CP13/CP14

(Bukry 1981) nannoplankton zone boundary.

FA LAFOGFX)GlT\FH Y

The benthic lorams Pseudoclavidina siibbotinae

Nikitina, Uvigerina spinocostata Cushman &

Jaivis, Vaginiilopsis decorata (Rcuss), Clavu-

linoldes szahoi (Hantkcn), Bulimifm madlenta

Gushman & Parker, Bolfvina cooki Cushman,

Spiroplectamina pishvanotute A. V. Furssenko &

K. B. Furssenko in the Sergeevka Section are

widespread in Lutedan deposits of \^arious Peri-

l'cthys localiries Irom Belgium to West

rurkmenia (Kaasschnirer 1961; Furssenko &

Furssenko 1961; Shuly.kaya 1970; Bugrova 1988;

Grigaylis et aL 1988; Naidin étal. 1994). The

fact ihar the Same foraminilera assemblage is

.spcead over au erionnous area in the northern

Peri-Tethy.s .suggests the existence ol a conti-

nuous bâsin with ubiquirous paUeobiologic

links. Moving along the line of sections studied

in the présent paper from norih-west to south-

easi, i.e., from Sergeevka Section to the

Boguchat boreliole, il can he seen thaï radiola-

rian assemblage.s are more taxonomically divers!-

464

GEODIVERSITAS • 1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donets Dépréssion

Pied and well-prescrved in Boguchar borehole

located in the souch-eastcrn parc of the région.

By the way, raxonomical composition of the ear-

liest complex at the base of section is close co

coeval associations of Knma Formation of South¬

ern régions, and thaï of youngcr R3-R5 assem¬

blages is similar to coeval complexes of Norway

Basin and Peri-Caspian Basin (Kozlova &

Petrushevska)^î 1979; Khokhlova 1996). Never-

thcless, radiolarians in this section represent an

association of an open marine basin with normal

salinit}^ Conversely, radiolarian composition in

borehole 9540 seems to reflect alicrnating open

marine and of shallow-water basin conditions,

possibly with a restricred connection with chc

main basin. Sedimenis ai the base of section

(Sergeevka maris) and Ln the upper part of the

section (Kas*yanovka siliccous clays, R5) contain

diversiPicd opcn-marinc radiolarian assodarions,

but in the middle part ot the section in clays of

the Tishki Formation, the radiolarian assemblage

(R3'R4) is represented by abundant spccimens

of Cenosphaera mitgarzi Lipman and sparse spéci¬

mens of Cyrtophormh alla Moksyakova and

Bûthropyramis sjx A strong prédominance of one

species is known to testify to the absence of

open-oceanic conditions, probably to low salinity

conditions.

The oldesc radiolarian assemblage is mosr abun¬

dant and diversiPied in rhe maris of vSergccvka

Formation in rhe section of the same namc, and

the youngest (R5) assemblage is mosi diversified

in KasVanovka Formation of Kantemirovka

Section.

CONCLUSION

The study of four sections of the eastern slope of

the Dnieper-Donets Dépréssion allowed us to

correct âge détermination of the Eocene

Formation.

The maris of Sergeevka Formation inost likely

bclong to uppermost Liitetian. Tlie benthic fora-

minifcral zone Psendoclaviilina sttbbotinae-

Uvigerinu spinocosicita-BoUxnna cookei distin-

guished liere can bc traced in the Keresta

Formation through much of the south of

European Russia, and in Vemmel and Ash for¬

mations of Belgium (Kaasschiter 1961;

Radionova et ai 1994). The upper part ol the

planktonic foraminiferal Acarininu rotiindimargi-

nata zone (bed with Globigerinatheka index)

found in the lower Sergeevka maris confirms this

âge détermination. Data based on nannofossils

(CP 13 Nanmtetritui'ioné) idcnrify the boundary

between theîr Lutet ian âge, roo.

The âge of the Tishki Formation is clearly

Bartonian. This interpretarioii is confirmed by

planktonic foraminifera of rhe Glohigtrina tnre-

rnenica zone. The diatom assemblages frorn the

base of the Sergeevka Formation and the lower

part of the Osinovo beds (Dl), in ihc upper pan

of the Tishki, Kas’yanovka and Kuma Forjna-

cions (D2) arc relaced to Pamlin oamaruensis dia-

rom zone of (Glczcr 1979) and to Cosdrwdiscus

suednehii zone of Strelnlkova (1992) scheme. In

Sergeevka Section, in assemblage Dl the index

.specics Pepotiia barbadensis Grevüle (Radionova

1996), and in D2, chc index spedes Brightwellia

imperfecta Jousé, which undoubtedly testify to

middle Eocene âge, were found.

Sédiments of the Kas yanovka Formation in ail

.studied sections contain almost the same diatom

assemblage. A notable featurc of the assemblage

is rhe presence ot Paralia onmaruensis (Grov^e 6c

Stuart) Gleser and Coscinodtscus sucehictus

(Sheshukova & Gleser) Gleser & Olshrinskaya,

tlie index-species of zones in local diatom

schemes of Glezer (1979) and Strelnlkova

(1992). This diatom assemblage rs very close to

the association obtained from the base of the

KhaEkov Formation in the northern part of

Dnieper-Donets Dépréssion (see Radionova et

al.y this volume, Fig. ]> borcholevS 3 and 4;

Radionova ci al. 1994). No évidence of the

upper Eocene âge for the Kas’yan Formation has

been found from radiolaria or diatoms, and we

confidenrly suggest the upper Bartonian âge for

KasVan Formation,

Acknowledgemen is

We vvould like to thank Prot. J. Meulenkamp

(Urreclu University, the Netherlands) and Prof.

D. La/arus (Berlin, Germany) which improved

the manuscript, Proi. P. De Wever and Dr S.

Crasquin-Soleau for general coordination and

GEODIVERSITAS • 1999 • 21 (3)

465

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

advice on this work, which is part of the Peri-

Tethys Program (Grants 95-11 and 95-96/11).

The other sponsor was the Russian Science

Foundation (Grant 05-95-15002).

REFERENCES

Anonymous 1989. — Decisions of the

Interdepartmental Stratigraphie Committee and it

permanent commissions. Volume 24. VSEGEi

Publications, Leningrad: 5T53.

Aubry M.-P. 198*3. — CorrèLuions biosnati^aphiques

entre les formations paléogènes épiconlinentales de

l’Europe du Nord-ouest, basées sur la rjarmoplancton

calcaire. Thèse» Université Pierre et Marie Curie,

Paris 6, 83-08, 208 p.

Beniamovskii V. N. 1995. — Refinement of the

Palaeogene Stratigraphical Schemc ou che South of

Russia vvith Sediinentological Cyclicity and Zonal

Detalisatiôn U$e fsvestia VIJZOV^ Geologia i

Razvedka (High School Report. Cieology and

Explorationj 45; 3-11 [in RussianJ.

Bugrova E. M. 1988. — The Foeme Foramintfersfrnm

the Southern IJSSR. Doctoiatc (Cjcol'Min.)

Dissertation, VSEGEI publication. Leningrad, 3 p.

Glezer Z. J. 1979. — Zonal Subdivision ol the

Palaeogenc Marine Siliceous Deposiis of ihe USSR

by Diatoms. Soinel Gcolo^ 11; 19-30 (in Russian].

Glezer Z. 1., ZocimavJcFi V. Yu., & Klyusbnikov

M. N. 1965. — The Diaioms from the Palacogcnc

Deposits of ihc Severnyi Doncts Basin and Theii

Stratigraphie Implications. Pahontologischeskii

Sbomik 2; 73-86.

Furssenko A. V. & Furssenko K. I. 1961. — The

Upper Eocene Foraminifers in Bélarus and l’heir

Stratigraphie Implications. Paicontology and

Stratigrapny of rhe BSSR. Aeademy oj Sciences BSSR

Puhiicatmn 3: 246-3f'>l [in Russian].

Kaaschierer J. P. 1961. — Foraminifera of the Eocene

of Belgium. Mémoire de l’institur Royal des Sciences

Naturelles de Beigique^VoSume 147.27 p.

Khokhlova 1. E. 1996. - Palaeogene-Eocene

Radiolariaas of rhe Russian PJatform South and

rheir application for direct corrélation with the Kast

Atlantic scdiment.s (.sire 400A DSDP). Fossil

Microorgunism as the hase of the PiMnerasoie stran-

graphes Corrélation and Paleobiogeop'aphy. Question

of micFopaleon(olog}'i Publishing office GEOSj»

Moscow 31; 70-82 tin Russian].

Kozlova G. E. 1990. — Phylogenetic Study of

Radiolarians as a basis for che development of a

Zonal scale of the Boréal Palacogene: 70-106 [in

Russian], //; Rudiolans tn Biostratigraphy. Ural

Branch USSR Academy of Sciences, Sverdiovsk.

Kozlova G. E. & Petrushevskaya M. G. 1979. —

Stages in Evolution of Radioiarians in Norway-

Grcenland Basin: 71-190 [in Russian], in Histury of

mïcropinnkum ùfNorway Sea. Nauka, Leningrad.

Kurlaev V. J. & Akhlestina E. F. 1988. — The

Paleogene ofthe Middle and Loiver Volga Région.

Saratov Universit)*, Saratov, 203 p.

Makarenko D. L.. Gorbunov V. S., Ivannik M. M.,

Maslun N. V.. Stotland A. B. & Blan M. Ya.

1987. — Stratigraphie Schetne for Palaeogene

Dcpo.dîs oj IJkHiine. Naukova Dumka, Kiev, 215 p.

|in Ru.ssian).

Martini E. 1970. — Standart Tertiary and

Quaternary calcareoiis naniiopiankton zonation.

Poe. U IHanktonic Conférence., Rome: 739-785.

Moksyakova A. M. 1972. — Bodrack Stage of the

Tuianian Plate. Sîratigraphy of Radtolarians and

Paieozoogeography. Ncdra, Moscow, 230 p. [in

Russian].

Harknd W. B., Amstrong R. A., Graig L. E.. Smoth

A- S. fie Smith D. (j. 1990. — A Geologcnl Urne

Scale. Cambridge IJniversitv Press. Cambridge,

263 p.

Naidin D. P.. Beniamovsivü V. N. Sc Kopaevich L. F.

1994. — Paléographie base of Stratigraphy

Reconstruction. Moscow State Univcisiry, Moscow,

136 p. [in Russian].

Okada U. & Biickry D. 1980. — Sunplemeiuary

modification and introduction of code number of

ihc low-lacitude coccotirh biostratigraphic zonation

Bukx}’, 1973, 1975. Mieropaleontology 5 (3): 321-

-325.

Radionova E- P. 1996. — Comparable Study of

Eocene l^iatoms from C)ccaniç and Platform

Sections (Notth Atlantic und Russian Plate). Fossil

Mfcroorganism as fhe base of the Phanerthoic stratT

gruphy^ Corrélation and Paleobiogeographyr Question

of micropaleontolugy, Puhiisbiug office GFOS,

Mostriw 31: 83-10! jtn Russiânj.

Radionova E P., Oreshkina T. V,, Khokhlova L E* &

Beniamovskii V. N 1994. — Eocene Deposits on

the Northeastern Slopc of the Dmeper-Donets

Dépréssion: Zonal Stratigraphy and Cyclic

Analysis. Stratigraphy and (jeolûguul Corrélation 1

(6): 563-580.

Semenov V, P. 1965. — Palacogene oj the Voronezh

Antcrlisc. Voronezh Univeisiry Publication,

Voronezh, 289 p. [in Russian].

Strelniltova N. 1. 1992. — Fhe Palaeogene Diaioms.

Sr.-Pcccrburg University, Si.-Pctcrsburg, 311 p. [in

Russiaitj.

Shtizkaya E. K. 1970. — Stratigraphy, Forarninifers

and Paieogeography uf the Lower Palacogcnc in

Crimea, Ciscaucasus, and we.srern part of Middle

Asia. Tmdy I A7G7?/, Trudy 70, 256 p.

Suhmitled for publication nuAlApnl J997;

accepted on 30 June 1998.

466

GEODIVERSITAS ■ 1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donets Dépréssion

APPENDIX

Table 1. — Stratigraphie range chart of nannofosslls in Sergeevka Section. A, abondant (more than 15 specimens); F, frequent (10-

15 specimens): C, common (3-9 specimens): R. rare (1-2 specimens).

Species/sample number

8

11

12

14

Blackites spinosus

F

R

Chiasmolithus solitus

R

A

C

Coccolithus formosus

A

C

R

Cycticargolithus floridanus

A

R

Discoaster barbadiensis

F

Discoaster binodosus

F

Discoaster distinctus

F

Discoasier nodifer

F

Discoasfer saipanensis

F

Discoaster strictus

R

F

Discoasier wemmetensis

F

Helicosphaera bramiettei

F

Helicosphaera fophata

F

Holodiscolithus macroporus

F

Neococcolithes dubius

F

Pontosphaera muftipora

F

Reticulofenestra dictyoda

C

F

Reticulofenestra haqü

A

C

F

Reticulofenestra umbilicus

A

C

Sphenolithus furcatoHtoides

F

Sphenolithus moriformis

F

Sphenolithus spiniger

F

Transversopontis pulcher

F

Table 2. — Stratigraphie range chart of foraminifera of Sergeevka Section, b, benthos: p, plankton. Legend: see Table 1.

Species/sample number

1 2

3

9

4

5

10

11

12

13

Acarinina bullbrooki

P

F

Acarinina pentacamerata

P

A

R

Acarinina cf. rotundimarginata

P

R

Clavulina cylindrica

b

R

F

R

F

C

F

Clavulinoides szaboi

b

C

A

R

C

F

Pseudoclavulina subboîinae

b

R

F

Spiroplectammina pishvanovae

b

F

Vaginulinopsis decorata

b

C

F

A

F

Uvigerina costulata

b

C

U\/lg9rina macilenta

b

C

A

F

Uvigerina spinocostata

b

c

C

GEODIVERSITAS • 1999 • 21 (3)

467

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

Table 3. — Stratigraphie range chart of radiolaria in Sergeevka Section. Legend: see Table 1.

Spectes/sample number

9

19

20

21

22

23

Calocydas semipolita

A

R

Clathrocyclas minima

C

Clathrocyclas extensa

A

Heliodiscus dupla

R

Heterosesrum formosum

R

F

Heliodiscus heliasteriscus

C

A

Heliodiscus zonatus

C

Heliodiscus fragilis

R

Heterosestrum îschuenkoi

R

C

Hexacontium pachydermum

R

Larcospira minor

R

Liîhomelissa sp. B

A

Lithomelissa sp. A

C

R

Lophocyrtis sinitzini

C

R

Meliîîosphaera magnoporulosa

C

Phacodiscus testatus

C

Porodiscus parvus

R

Spongomelissa sp. A

C

Sîylodyctya irregularis

R

C

Stylotrochus radiatus

R

Theocyrtis liîhos

C

F

R

Thecosphaera californica

R

Tripodiscinus aff. clavipes

F

Tripodiscinus kaptarenkoe

C

R

Tripodiscinus aff. tribrachiatus

F

468

GEODIVERSITAS

1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donets Dépréssion

Table 4. — Stratigraphie range chart of diatoms and silicoflagellates in Sergeevka Section. Legend: see Table 1.

Species/sample number

9

19

20

22

Diatoms

Arachnoidiscus ehrenbergii

F

Arachnoidiscus asieromphalus

R

Aulacodiscus excavatus

C

F

Azpeitia aff. oligocenica

R

Brightwellia imperfecta (?)

R

Corona retinervis

F

Coscinodiscus bulliens

F

Coscinodiseus obscurus

C

Coscinodiscus obscurus var. cancavus

C

F

Cosmiodiscus breviradiatus

F

Coscinodiscus paiera (?)

R

Craspedodiscus moelleri

F

R

F

R

Cristodiscus (Coscinodiscus) succinctus

R

F

A

Cristodiscus crux

F

Cristodiscus decrescenoides

F

A

Hemiaufus polymorphus var. charkovianus

F

Hyalodiscus radiatus

F

R

Hyalodiscus inflatus

C

Hyalodiscus johnsonii

R

F

Hyalodiscus kelleri var. fasdculatus

C

F

Melosira architecturalis

F

C

Metosira fausta

F

Paralia oamaruensis

C

Paralia sulcata var. sibirica

C

Peponia barbadensis

R

Pseudopodosira hyalina

F

C

Pseudopodosira bella

F

Pseudopodosira westii

F

C

Pseudotriceratium chenevieri

R

Pseudotneeratium pyleyformis

F

Pyxidicula charkoviana

F

A

C

F

PyxHIa gracilis

F

Pyxilla schenkii

R

Pyxilla tchernovii

R

Trinacria excavata

F

Triceratium aff. kanaya var. trilobata

R

F

Triceratium ventricosa

C

Silicoflagellates

Dictyocha spinosa

F

Distephanus pentadonus

F

Distephanus grunowii

R

F

Navieufopsis constricta

F

Naviculopsis oamaruensis

F

GEODIVERSITAS

1999 • 21 (3)

469

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

Table 5. — Stratigraphie range chart of nannofossils in Kantemirovka Section. Legend: see Table 1.

Species/sample number

27

28

29

30

33

Blackites spinosus

F

Chiasmolithus solitue

F

Chiasmolithus tituf

F

Coccolithus formosus

A

C

R

F

Cyclicargolithus ffohdanus

C

A

C

R

F

Discoaster barbadmnsis

C

F

Discoaster bifax

R

F

Discoaster binodosus

R

F

Discoaster defJandreis

R

F

Discoaster saipanensis

F

Discoaster strictus

F

Discoaster onustus

R

F

Helicosphaera bramlettei

F

Helicosphaera serninulum

F

Nannotetrina cristaîa

F

Neococcolithes dubius

C

R

F

Pontosphaera muftipore

F

Pontosphaera duocavus

F

Reticulofenestra coenura

A

R

F

Hetieufofenestra bagii

A

C

F

Reticuloferiestra umbilicus

C

R

F

Sphenolithus rnoriforrpis

F

Sphenolithus obtusus

F

Sphenolithus radians

F

Transversoponîis pulcher

F

ZygrhabUthus bijugatus

R

F

Table 6. — Stratigraphie range chart of foraminifera in Kantemirovka Section, b, benthos; p, plankton. Legend: see Table 1.

Species/sample number

27

28

29

Acarinina rugosoaculeata

P

F

Bolivina cookei

b

F

C

Bulimina scufptilis

b

C

Clavulina colomi

b

C

c

C

Clavulina cylindrica

b

C

c

Clavulinoides szaboi

b

A

c

Globigerinatheka index

P

R

Pseudoctavulina subboiinae

b

F

c

Pseudohastigerina micra

P

F

C

Spiroplectammtna ptshvanovae

b

F

C

Subbotina turcmenica

P

C

A

Vaginulinopsis decorata

b

F

c

C

Uvigerina costellata

b

C

c

Uvigerina macitenta

b

C

c

Uvigerina spinocostata

b

C

c

470

GEODIVERSiTAS • 1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donets Dépréssion

Table 7. — Stratigraphie range charl of radiolaria in Kantemirovka Section. Legend: see Table 1.

Species/sample number

39

40

41

42

43

44A

Baîhropyramis aneotos

F

Calocyclas asperum

R

Calocyclas semipolita

R

Ceratospyris sp. aff. T. crassipes

R

Clatrocydas extensa muftiplicata

R

Clathrocyclas talwanü

R

Clathrocydas sinitzini

F

Clathrocydassp. 1

R

Conocaryomma sp.

C

Cyrîophormis alta

C

Heliodiscus heliasteriscus

A

Hefiodiscus zonaîum

C

Heliodiscus fragilis

C

F

Heterosestrum formosum

A

Heterosestrum tschuenkoi

A

Hexacontium aff. pachydermum

A

C

Lithelius foremanae

C

Lithomelissa sp. A

C

A

C

Lithomelissa sp. B

C

Lithelius foremanae

C

Mefittosphaera magnoporulosa

C

R

Pseudodyctyophimus sp.

C

Stylodyctya irregulare

C

Stylosphaera coronata

F

Theocyrtis lithos

Theocyrtis andriashevi

Tripodisdnus kaptarenkoe

R

A

Velicucculus aff. oddgurneri

R

Tripilidium clavipes

Stylosphaera balbis

F

Tripodisdnus sp.

A

GEODIVERSITAS

1999 • 21 (3)

471

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

Table 8. — Stratigraphie ranges chart of diatoms and silicoflagellates in Kantemirovka Section. Legend: see Table 1.

Species/sample number

39

40

42

43

44A

Diatoms

Aulacodiscus excavaîus

F

Aulacodiscus kelleri y/ar. fasciculatus

F

Arachnoidiscus ehrenbergii

F

Brightwellia coronata

R

Cerataulus deflandrei

F

Corona retinervis

F

CoscincKiiscus obscums

F

C

Coscinodiscus obscums var. cancavus

F

C

Coscinodiscus asteromphalus

F

Coscinodiscus decrescenoides

C

F

C

Cristodiscus {Coscinodiscus) succinctus

F

c

C

Hemiaulus polymorphüs var. charkovianus

C

F

Hemiaufus tchemovii

F

Hemiaulus polycysHnorum

F

Melosira architecturalis

c

C

F

Paralia sulcata var. sibirica

C

c

C

Paralia oamaruensis

C

c

C

F

Pseudopodosira hyalina

C

c

C

Pseudopodosira pyleiformis

c

F

Pyxilla gracilis

F

Pyxidicula charkoviana

F

c

F

Pyxidicuia johnsonii

A

F

Pyxidicula aff. moellerî

F

Thalassiosiropsis wittiana

F

Triceratium ventricosa

F

Triceratium aff. kanaya var. îriloata

R

Triceratium unguiculaîum

R

Tricacria excavata var. tetragona

F

Silicoflagellates

Dictyocha deflandrei

F

Mesocena oamaruensis

F

Naviculopsis constricta

F

Naviculopsis foliaceae

F

472

GEODIVERSITAS • 1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donets Dépréssion

Table 9. — Stratigraphie range chart of nannofossils in Rudaevka (borehole 9540). Legend: see Table 1.

Species/sample number

61-5

60-5

56

Blackites spinosus

C

Chiasmolithus grandis

F

Chiasmolithus solitus

C

F

Chiasmolithus tituf

F

Clathrolithus spinosus

F

Coccolithus formosus

R

F

Coccolithus pelagicus

R

Cyclicargolithus floridanus

A

C

Discoaster barbadiensis

F

Discoaster bifax

F

Discoaster distinctus

R

F

Discoaster nodifer

R

F

Discoaster saipanensis

F

Discoaster strictus

R

Hslicosphaera bramlettei

F

Helicosphaera lophota

F

Neococcoliihes dubius

C

F

Pontosphaera duocavus

F

Pontosphaera multipora

F

Reticuiofenestra umbilicus

C

F

Rhabdosphaera gladius

F

Table 10. — Stratigraphie range ehart of radiolaria In Rudaevka (borehole 9540). Legend: see Table 1.

Species/sample number 60-5 59 53-5 51 50 49-5 47 45 43-5 39 35 33

Stylodyctya hastata F

Cenosphaera mitgarzi

Thecosphaera minor R

Heliodiscus heliasteriscus F

Cfathrocyclas prindpi principi R

Lithomelissa sp. A F

Stylotrochus sp, F

Hexacontium pachydermum

Stylodyctya irregularis

Petalospyris aff. dubia

Clathrocyclas exiensa

Theocorys reticula

Heterosestrum formosum

Heterosestrum tschuenkoi

Stylospbaera coronata laevis

Tripodiscinus îumulosus

Hiphospira ocellata

Thecosphaera californica

Lithomelissa aff. haeckeii

Cenosphaera micropora

Cyrtophormis altus

Perypyramis circumtexta

Calocyclas semipolita

Lophophaena sp. B

Heliodiscus zonatus

Theocyrtis andhashevi

F

C C

F

C C

F

F F

F C

F C R

F

R

F R

A A C

F R

R

A CA

F

C F

F

A

C

GEODIVERSITAS • 1999 • 21 (3)

473

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

Table 11. — Stratigraphie range chart of diatoms and silicoflagellates in Rudaevka (borehole 5420). Legend: see Table 1.

Species/sample number

60-5

53-5

50

47

38

37

35

34

33

32

Diatoms

Aulacodiscus excavatus

Aulacodiscus ketlen var fasciculatus

Cerataulus deftandrei

F

Corona retJnefvis

F

Coscinodfscus buHiens

F

Coscinodiscus obscurus

F

C

R

Coscinodiscos obscurus var. cancavus

C

A

F

C

Coscinodiscus asteromphalus

F

Coscinodiscus decrascens

F

Coscinodiscus decrescenoides

Cosmiodiscus breviradiatus

Cristodiscus suedndus

F

Cristodiscus duplex

Craspedodiscus moelieri

F

Craspedodiscus oblongus

Hemiaufus polymorphus var. charkovianus

Hemiaulus tchernovii

Hyalodiscus radiatus

F

C

F

C

Mefosira architecturafis

C

F

Paralia oamaruensis

C

F

C

Pseudopodosira hyalina

F

C

Pseudopodosira westii

Pseudopodosira pyleyfortnis

Pseudopodosira bella

F

C

F

Pyxilfa gracHis

F

Pyxidicula charkoviana

Pyxidicula grunowii

F

C

F

C

Pyxidicula aff. moelieri

Pyxidicula johnsonii

F

C

F

Pyxidicula marginata

Pyxidicula megapora

R

F

Triceratium kanaya var. trilobata

Triceratium venîricosa

Tricacria exca\rata

F

Silicoflagellates

Corbisema hastata globulosa

F

Corbisema iriacantha

F

Dictyocha deflandrei

Dictyocha spinosa

Distephanus pentadonus

F

Naviculopsis foliaceae

C

Naviculopsis constricta

C

Naviculopsis nordica

c

Corbisema triacantha

F

474

GEODIVERSITAS • 1999 • 21 (3)

Eocene stratigraphy of the Dnieper-Donets Dépréssion

Table 12. — Stratigraphie range chart of radiolaria in Boguchar {borehole 5-93). Legend: see Table 1.

Species/sample number

63-4

62-1

60-1

31-5 31

30

23-4

17-4

16

12 11

Thecosphaera cafifornica

F

Calocyclas semipolita

C

Hefiodiscus heliasteriscus

C

Lychnocanium bellum

F

Artostrobus aff. annulatus

F

Stylodyctya irregularis

A

Petalospyris dubia

C

F

Lithomelissa haeckeli

F

Hexacontium pachydermum

Hexacontium sp.

R

F

F F

F

Spongomelissa sp. 1

Lithomelissa sp. A

C

Stylosphaera coronaîa coronata

C

F

Heliodiscus dupla

F

Tripodiscinus aff. vanus

Heterosestrum formosum

F

C

Stylotrochus radiatus

C

Heterosestrum thcuer)koi

Heterosestrum shabalkini

R

Clathrocyclas taiwanii

Cenosphaera mitgarzi

Theocyrtis iiîhos

C

F

R

Theocorys reticula

A

Artobotrys non/egiensis

F

Lithomelissa stigi

Peripyramis anoetum

R

C

Lithelius spiraiis

Thecosphaera minor

R

C

R

Cyriophormis alta

C

R

F

Tripodiscinus tribrachiatus

F

R

Tripodisciunus kaptarenkoi

F

C

Theocyrtis andriashevi

R

F

Haliomma immensa

Calocyclas asperum

R

A

C

Rhodosphaera donensis

R

C

GEODIVERSITAS • 1999 • 21 (3)

475

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Shcherbinina E. K.

Table 13. — Stratigraphie range chart of diatoms and silicoflagellates in Boguchar (borehole 5-93). Legend: see Table 1.

Species/sample number

63-4

62-1

60-1

29-5

28-2

24-2

17-1

15-1

Diatoms

Actinoptychus intermedius

Aulacodiscus excavaius

F

Aufacodiscus keHeri var. fasciculatus

Aulacodiscus inflatus

Azpeitia atf. ofigocenica

F

R

F

Brightwelfia sp.

Cerataulus deflandrei

F

R

F

Corona retinervis

F

Coscinodiscus bulfiens

F

Coscinodiscus obscurus

C

F

Coscinodiscus obscurus yar. cancavus

F

C

Coscinodiscus asteromphalus

Coscinodiscus decrescens

F

R

Coscinodiscus marginatus

Coscinodiscus decrescenoides

F

Cosmiodiscus breviradiaius

Cristodiscus succinctus

F

Cristodiscus duplex

F

Craspedodiscus moollen

F

Craspedodiscus oblongus

F

C

Hemialus polycystinorum

F

H. polymorphus var. charkovianus

F

C

Hyalodiscus radiatus

R

F

Melosira architecturalis

F

C

Paralia sulcata var. sibirica

C

Paralia oamaruensis

F

C

R

Pseudopodosira hyalina

C

F

C

F

Pseudopodosiia pyieytormis

F

C

F

Pseudopodosira bella

C

Pyxilla gracilis

F

P. oligocenica var. oligocenica

F

Pyxidicula charkoviana

F

C

Pyxidicula gmnowii

F

Pyxidicula aff. moelleri

F

Pyxidicula johnsonii

Pyxidicula crenata

Pyxidicula megapora

F

Pyxidicula spinodissima

Stellarima mucrotrias

F

R

Triceratium ventricosa

F

C

Triceratiumatf. kanayayar. triloata

F

Tricacria excavata

Tricacria exsculpta

F

Silicoflagellates

Corbisema hastata globulosa

F

Corbisema enermis

F

Dictyocha deflandrei

Dicîyocha spinosa

Dictyocha hexacantha

F

Disîephanus pentagonus

Naviculopsis foliaceae

F

C

Naviculopsis constricta

F

Naviculopsis nordica

C

476

GEODIVERSITAS • 1999 • 21 (3)

Some peculiarities concerning the Pliocène

évolution of the Black Sea and Caspian basins

Edward A. MOLOSTOVSKY & Andrew Yu. GUZHIKOV

Institute of Geology, Saratov State University,

Moskovskaya Street, 161, Saratov 410750 (Russia)

guzhikovay@info.sgu.ru

Molostovsky E. A. & Guzhikov A, Yu, 1999. — Some peculiarities concerning the Pliocène

évolution of the Black Sea and Caspian basins, in Crasquin-Soleau S. & De Wever P.

(eds), Peri-Tethys: stratigraphie corrélations 3, Geodiversitas 21 (3) : 477-489.

KEYWORDS

Petromagnetism,

scalar magnctic characteristics,

magnetic susceptibility,

Para-Terhys,

Pliocène.

ABSTRACT

This paper présents the results of petromagnetic studies on Pliocène key sec¬

tions of Crimea, Georgia, rhe Apscheron Peninsula and the North Cis-

Caspian Région. Scalar magnetic characteristics of sedimentary rocks reflects

the conditions they hâve been formed in the eastern Para-Tethys. The

Pliocène activation is recorded by increased rock magnetism in the middle

Pliocène. The dependence of petromagnetic variation.s upon cectonic factors

allows to correlate the marine Pliocène succession from the Ponto-Caspian

District.

MOTS CLÉS

Petromagnéti-sme,

caractéristiques magnétiques

scalaires,

susccptibilUc magnétique,

Para-Tétnys,

Pliocène.

RÉSUMÉ

QueUfues particularités de l'évolution pliocène des bassins de la Mer noire et de la

Caspienne.

Cet anicle présente les résultats d'études pétromagnétiques des dépôts plio¬

cènes de Crimée, de Géorgie, de la péninsule d’Apscheron et de la région

nord de la Cis-Caspienne. Les caractéristiques magnétiques scalaires des

roches sédimentaires reflètent les conditions dans lesquelles elles ont été for¬

mées dans la Para-Térhys orientale. L'activation pliocène est enregistrée par

une augmentation du niagnéri.smc au Pliocène moyen. La dépendance des

variarions pétromagnétiques vis à vis de.s facteurs tectoniques permet la corré¬

lation des dépôts marins de la région Ponto-Caspienne.

GEODIVERSITAS • 1999 • 21 (3)

477

Molostovsky E. A. &C Guzhikov A. Yu.

INTRODUCTION

Tectonic activity of rhe Caucasus and adjacent

mountain areas ac che Miocene-Pliocene transi¬

tion has speeded up rhe disintegrarion and final

disappearance of the Para-Tethys Basin. The west¬

ern Para-Tethys disappeared and the easrcrn

Para-fcthys was ultimately disintegrated at rhe

end of the early Pliocène, which resulted in the

final isolation of the Pontic and Caspian seas

(Nevesskayxt et al 1986).

Since rheir development proceeded praccically

independently, though occasional réunification

through the System of latitudinal Kuma-Manych

dépréssions was establishcd. The géologie record

of ihe Caspian waeer hicak-chrough into rhe Cis-

Pontic Région at the end of the middle

Actchagylinn (the beginning of Matuyarna

epoch) is mosT clearly demonstrated by che beds

with cominon niollusc fauna; lamanian beds

containing the Actcliagylian Cai'dîmn in the Cis-

Pontic Région and the Pontic Dreissenia within

the Actchagylian of the Caspian Section

(Kitovani 1976; Nevesskaya et al. 1986; Zubakov

1990).

The general évolution .scheme of isolated Peri-

Tethys basins was traditionally bascd on liiho-

facies and palaeontological data. Palaeomagnccic

research, especially aller Harland ci al. (1982)

magneiochronologic scale, provided the franie-

work for more solid and précisé corrélations of

géologie evencs in the Black Sca and Caspian

régions. Recent research hâve demonstrated rhat

most iiucrcsting stratigraphie, palaeogeographic

and geochcmical intormarion is to be found in

scalar magnetic characrerisrics of sedimentary

rocks; the ' magnecic memory" of these rocks

reflects ihc main events of their formation in

varions geodynamie and landscape-climatic set-

tings (Molostovsky 1986; Gu;thikov &

Molostovsky 1995).

The resulcs of palaeo- and pciromagnetic re

search of the marine Plioccne and PIcistoccnc

front the Ketch Penin.sula, western Georgia and

Apsheron Peninsulaarc presented (Fig. D-

In this study beside palaeontological, palvnologi-

cal and lithologic-mineralogical data, a substan-

tial amount of original and previously publishcd

palaeomagnetic data was used for palaeogeogra-

phic reconstructions (Ali-Zade 1954; Khramov

1963; Asadulacv ôc Pcvzner 1973; Trubikbin

1977; Zubakov 1990). The aurhor.s garhered rhe

matcrial on scaJar magnetic characteri.sdcs and

add data from Ismail-Zade (1967) and Khramov

(1963).

Magnetic susceptibilitics were measured by IM V-

2 and KT-5 devices, rémanent magnétisation -

by spinaer-magirccometers ION-1, JR-3, JR-4.

The basic palaeomagneiic maierial used for com¬

parative analyses is summarised in a corrélation

scheme showing with rhe PÜoeene stratigraphie

unies from the Black Sea and Caspian régions in

relation to the general magnetosiraiignaphic scale

(Fig. 2).

MAIN PRINCIPLES OF STR.\TIGRAPHIC

INTERPRETATIONS OF

PETROMAGNETIC DATA

Pctromagnetic variations of sedimentary

scquenccs are controlled by the depositional pro-

cesses and boundary conditions thar déterminé

the formation of these unirs. Therefore, a subdi¬

vision of strarified rocks based on common scalar

magneric characteristics, has sedimento-stratigra-

phic significance.

l he sedimentary rock magnetic properties are

dererniined by bodi natuial (magnetic suscepti-

biiity — k, modulus of naturaJ rémanent magnéti¬

sation — Jn, etc.) and artificial parameters i.e.

measured after exposure to température and/or a

laboratory magnetic ficld (magnetic susceptibili-

ry of a sample after exposure to température -

dk, saturation magnétisation—Js, saturation field

- Hs, etc.).

The values of natural pctromagnetic cliaracteris-

tics - magnetic susccpfibility (k) and natural

rémanent magnétisation (NRM, Jn) — dépend

mostly on fcrromagnetic minerai concentrations

as wcll as on magnetic phase compo.siiions,

secondât}' changes and otliers. The Jn modulus is

mainly controlled by the dcgrec of order of

domain magnetic moments, which results in

higher jn in chemically magnetised rocks than in

ihosc with orientational magnétisation, while

magnetic susccptibiltty values do no vâry. In

weakly magnetised rocks (k = 10-20.10'*^ SI

478

GEODIVERSITAS * 1999 • 21 (3)

Pliocène évolution of Black Sea and Caspian basins

I 1 1

Limits of States

" — f\,

Mountains ranges

Limits of Russian régions

Sections

Fig. 1. — Location map. I, Great Caucasus; 11. Adjar-Trialel mountain System; III, Balkhan; IV. Kopet-Dag; V, Talysh Mountains.

Sections: a, wells 1, 5, 13, 14, 15, 18, 19 (Samara Région); b, well 3 (Saratov, Volga Région); c, well 20 (Saratov, Volga Région);

d. well 13 (Kalmykia); e, well 48 (Kalmykia); f, Kerch Peninsula; g, western Georgia.

GEODIVERSITAS • 1999 • 21 (3)

479

Molostovsky E. A. & Guzhikov A. Yu.

International

paiæomagnetic

scate

(Harland efa/.1982)

Time

(Ma)

1

2

3

4

Apsheron Peninsula

Western Turkmenia

Asov Sea

(Khfamciv1963) (Peuzner1973)

(Trubikhin 1977)

Taman

(Zubakov 1990)

Fig. 2. — Corrélation between palaeomagnetic sections of the Pliocène from eastern Para-Tethys.

units) paraniagnctic componcnts strongly affeci

k-value formation. AU the perromagiietic indices

are funcrionally associared with sédiment com¬

position. ccxiLiral-structuraJ rock features, palaeo-

geographic and gcochemical çediment compo¬

sition epigenetic changes, i.e., with ail parameters

controlling the formation of the large sedimcn-

tary complexes within concrète palaeobasins.

The obvions relationship between petromagne-

tism and sédimentation processes provides

potentially a wide application of scalar magnetic

characteristics in solving diverse géologie pro-

blems; the petromagnetic method can be consi-

dered as a form ol rhythmostratigraphic analysis*

Detailcd kjiowlcdge ot the ferromagnelic-

fraction mineralogy forms the fondamental basis

in the interprétation of such data.

A large amoum of data on magnetic properries of

sedimentary formations of diverse âges and gene-

sis were summarised by the authors; chis made it

possible to forniulate the main principles of

palaeogeographic interprétation of petromagnetic

indices. The essence of these principles accounts

to:

l. Magnetic différentiation of rocks within a

stratigraphie section is controlled by the changes

in sédimentation environments.

In rocks wâth syn- or posc-sedimentary magnéti¬

sation carried by alloihigenic fçriomagnctics,

palaeogeographic and tcctonic factors arc defini¬

tive, i.e., chose conrn.ïlling terrigenous magnetic

material érosion, transport déposition (rectonic

activity, climatic changes affccting the rate of

baring processes). The increased concentration of

480

GEODIVERSITAS • 1999 • 21 (3)

Pliocène évolution of Black Sea and Caspian basins

detritic ferromiignerics \s regisiered by k and Jn

bursts on pccroinagnetic ciirves.

In rocks with chcmically introduced NRM

containcd by authigenic minerais, magnetic pro-

perties are controlled by chc geochemical envi-

ronmenr dnring the fonnarion of rhe authigenic

magnetic phase. Forexaniple^ in reducing condi¬

tions due to some sulphur defteie, authigenic sul-

phidc minéralisation is observed wirhin the

sédiments with strongly magnetised pyrrhotine

and greigire being fbrmed logethcr with pyrite.

Variations in geochemical conditions may resuit

in variation in different distribution of magnetic

sulphides within a stratigraphie sectiom which is

regisrered by changes iu magnetic susceptibility

and natural rémanent magnétisation.

2. The levels of subsrantial changes in sedlmenta-

ry sequence magnetism constitute rhe natural

interfaces beeween real stratiform bodies, and the

pctromagneiic laycr-sets ihcmselves may be clas¬

sifiée! as stratigraphie unit-S of local or régional

importance.

3. Sédiment petromagnctic différentiation in

time is of regular characier and reflects sédimen¬

tation peculiar and reflects changes in sédimenta¬

tion processes and environment. Spasmodic

petromagnctic changes generally coincide with

sharp changes in sedimentarion.

4. Petromagnetic rh^'thms within periods of éro¬

sion or non-déposition parallel sédimentation

rhyrhms.

In case of derrital nature ol Jn, rhe inirial (régres¬

sive) stages of sedimenration cycles are marked by

a drop in magnétisation. When magnetic rhythm

is controlled by changes in palaeogcochcmical

conditions significanr increases in Jn and k are

observed in deep-water sédiments, containing

authigenic phases - pyrrhotine and grcigite,

which formed iinder the reducing conditions.

5. Petromagnetic variations, observed ahcr heat-

ing ol samples in laboratocy, reflect concentra¬

tion variations in originally non-maguetic or

vvcakly magnetic terriferous minerais (pyrite,

marcasitc, siderite, iron hydroxide.s). Ihese

minerais are clcarly recorded magnetometrically

after conversion under elevated température.

Pyrite and marcasife, lor example, when heaied

up to 500 "C in oxidisiiig medium, turn into

magnetite, which results in magnetic susceptibili-

æ magnetic susceptibiiity

(10'^SI units)

0 10 20 30 40 50

I.. .. ..I ■... I.... I

LImestones

Absence

of deposits

Maris

Clays '

“i i .

Iron ores

Fig. 3. — Synthetic petromagnetic curve of Pliocène deposits of

the Kerch Peninsula.

ry increase. The increase in Dk = k^-k reflects the

content of newly-formed magnetite, and thus,

concentrations of inirial FeS 2 .

If non-magnetic iron sulphides are of authigenic

nature, the abnormally high increase of magnetic

susceptibiiity mirrors the reducing environment

in a sedimentary basin, with rhe presence of

hydrogen sulphide; dk - curve variations form

ihe basis for detailcd sequence division and let

yield constrain on the changes in redox poten-

tials of sédimentation environment.

GEODIVERSITAS • 1999 • 21 (3)

481

Molostovsky E. A. & Guzhikov A. Yu.

INVESTIGATION RESULTS

æ magnetic susceptibility

(10 ^Sl units)

0 200 400 600 800 1000

Aleurolltes

Clays

O O

Sandstones

Pebbles

q Limestones

Absence

of deposits

Kerch Peninswjk

Reconstruction of palaeogeographic events on

rhe basis of the palaeo- and petromagneric data

of the Black vSea Région, is possible from the end

of the Miocene ro the beginning of the Pliocène.

The analyses ol several composite sections

through the Meotian and Pontian beds in Kerch

Peninsula detnonstrate rhar similar changes in

magnetic properties can be observed in sédi¬

ments from various parts of ihc bâsin.s.

Claycy-carbonate deposits of Meotian âge in the

north-western Cis-Pontiç Région are ubiquitous-

ly distinguished for extremely low and homoge-

neous magnétisation. Their magnetic smseep-

tibilicy varies bervveen 3 and 8.10 ^ SI units.

1 hc beginning of the Pontian transgres.sioii in

the large Eüxinic Basin was accompanied by

accumulation of dark-grey deep-water clays,

dominating practically in ail the sections from

western Georgia and Kerch-Taman régions. The

beginning of the Pliocène is everywhere marked

bv sub-srantial changes in marine sédiment petro-

magnelism.

Within the Pontian beds of Kerch Peninsula, the

level of magnétisation is at least two rimes higher

than in the Meotian tcrrigenous-carbonate

sequence. Modal k values, hcrc, arc as high as

15.10 '' SI units (Fig. 3).

During the Kiminerian, deep-water clay accumu-

lated. Thèse clays coniain intercalations of che-

mogcnic sidcfitc-lcptochlorite ores in the mîddle

parc of the section which was deposited in the

Kerch and Taman areas. The intcrlayers rcsultcd

from érosion and transport to rhe littoral zone ot

the local latente crusts ol wcathering (Zubakov

1990).

d'he incrcased iron-salt contents in the middle

Kimnicrian .sedimenrs had relatively small

influence upon their magnetic properties due to

the absence of strong magnetic phases. Magnetic

suscepribilities in iron ores are increased (20-

55.10'^ SI unies) relative to those of the host

rocks (k^„^|= 12.10’^ SI units).

Fig. 4. — Synthetic petromagnetic curve of Pliocène and

Pleistocene deposits of western Georgia.

Break of ero.sion of the laterite-crust at the end of

the Kiinmetian is recorded by a marked magnéti¬

sation decrease in the rocks of the upper

482

GEODIVERSITAS • 1999 • 21 (3)

Pliocène évolution of Black Sea and Caspian basins

Kimmerian and Kuyalnikian where the k values

do not exceed 14.10''' SI units (Fig. 3).

Western Georgia

Perromagnetic différentiation in western Georgia

is much more marked than in the norch-western

Cis-Pontic Région, in spite of the homogenous

character of the section composed of grey deep-

water clays, with some sandstones and aleuro-

lites.

The Meorian/Pontian boundary is recorded as a

clear change in perromagnetic respon.se of the

sequence (Fig 4). In western Georgia, the

Meotian claycy-aleuroliric sequence is also distin-

guished for low magnétisation: = 20.10'^ SI

units. Magnedc susceptibility values are signifi-

canrly higher in the lower part of the Pontian

section; they vary between 20-200.10 '' SI units.

Sédiment magnétisation increascs steadily

upwards along the section, and within the upper

horizons ol the Pontian, rhe k values vary bet¬

ween k = 40-300.10'^ SI units.

Magnetic susceptibility values increase up to

200-800.10'^ SI units, in the Kimmerian, rea-

ching the maximum in rhe clays and aleurolite of

the Kuyalnik, Gurian and Chaudian horizons:

k = 300-1300.lO-'^ SI units (k^„^ = 660.10'5 SI

units).

In the Pleistocene, the transport of terrigenous

magnetic matcrial dccrcased significantly, its

input to the ancient Euxinic Basin was more epi-

sodic. This is marked by alcernatiott of strongly

and weakly-magnedsed layers in the petromagne-

tic records. In weakly magnetised sédiments the

k values var)' between 9 and 40.10 SI units, in

strongly magnetic sédiments k = 80-320.10'^ SI

units (Fig. 4).

Thick (up to 3500 m) Pliocène deposirs wirh

unique magnetic propeities, were formed in west¬

ern Georgia at the end of rhe Caino/.oic. Judging

from petromagneric data, the processes of marine

accumulation in ihis région were malnly control-

Icd by intensive ascending movements of rhe west¬

ern part of rhe Grear Caucasus and Adjar-Trîalet

Mountain System. Their acrivity is usually correla-

ted with the middle/lare Pliocène transition

(Kitovani 1976) but the petromagneric record

clearly indicaies that tectonic accivity srarted as

early as the earliest Pliocène.

Fig. 5. — Synthetic petromagnetic curve of Pliocène deposits of

the Apsheron Peninsula {Khramov 1963; Ismail-Zade et al.

1967).

Magnetic material was mainly provided by the

Eocene volcanic envers, widely spread in the

Southern régions of Georgia. The érosion of

highly-magnetic sequences in rhe mountains

continued with increasing intensiry right up to

the end of the Pliocène. Baring rates seemed to

hâve decreased in the Pleistocene, but the présen¬

ce of magnetite-saturated beach sands in the vici-

GEODiVERSITAS • 1999 • 21 (3)

483

Molostovsky E. A. & Guzhikov A. Yu.

nity of che towns of Poti, Ureki and Magnetiti

(Guria) sugge^ir vhar the process continue.

Petromagnetic section corrélation with the

magnetochronologic scalc suggescs that the

Adjar-Trialet Mountain massif is ihe most active

geodynainic centre of the Black Sea région for

the last 5.4 Ma: intensive baring continues since

the beginning of Gilbert epoch (Fig. 4).

The transgres.sive'regressive variations of the

Euxinic Basin, tonirary to the north-western

Cis-Ponric, are not clearly reHecced in rhe

Georgian sections, though chcy are easily reco-

gnised trom numerous unconformities within

the Pliocène secjuence. 1 he mosi expressive trace

was left by the Kimmcrian activation, which

resulted in strong réduction of Gauss zone in

many sections.

Caspïan Région

No petromagnetic data on the lowcr Pliocène

from the Caspian Région is available. In che

middle Pliocène portion of the seule, the produc¬

tive sequence front Apsheron Peninsula is relan-

vely well srudied, as well as its corrélative red-bed

(Cheleken) suite front western Turkmenia

(Khramov 1963). These rock complexes were

deposited in semiTreshwater basins with intensi¬

ve terrigenous sédimentation; ihe basins origina-

ted in the Caspian Région during che Kim-

merian transgression of the Euxinic Basin

(Muratov & Nevesskaja 1986).

The Kimmerian tectonic event did nor leave any

notable traces in the petromagnetic secrion from

the TranS'Gaspian due ro che lack of highly

magnetic source rocks in rite western Kopet-Dag

and Balkhan. The redstones, aleuroliies and clays

of the Cheleken sviite are generally cliaracterised

by moderate magnétisation (k = 15-25-10 '' SI

units) and arc poody dilfcrcntiated along the

stratigraphie section (Khramov 1963).

The petromagnetic section through che produc¬

tive sequence from Azerbaijan is more informative

in rhis respect (Fig. 5). Accord!tig to Khramot^

(1963) and Lsmail-Zade et ni (1967) data, ihe

lower part ol this large terrigenous complcx

("800 m) is composed of low-inagnctiscd clays,

aleurolites and sandstoncs with the average k va

13.10"'' SI units. In the upper part of the

Sabunchi suite, a sharp magnétisation increase is

observed in ail rock varieries, accompanied by a

substanrial dispersion of scalar magnetic charac-

terisiics; k = 13-160.10'^ SI unic.s = '^5.

10*'' SI units). A similar m;tgnetisanon levcl is

characterisiic of the overlying Surakhan suite; the

overall ihickne.ss of rhe highly magnetic complex

constitutes up to 450-500 m (Fig. 5).

Tfie large volumes ol magnetic material trans-

ported to the regress'ing Balukhan réservoir might

hâve been caused by the increa.sed tectonic aaivi-

ty of the eastetn flank of rhe Créai Caucasus or

the Talysh Mountain massif in the Southern Cis-

Caspian. In atiy case, the intensive baring of

Mesozoic and Palaeogcne volcanite séquences of

intermediate and basic composirion, resulted in

the rfccumularion of magnetic material in the

upper horizons of the productive seqtiences.

The Pliocène activity in the eastern Caucasus is

dated rather precisely by ihc magnetostrati-

graphic scalc (Fig. 5) as the end of Gilbert epoch

plus the eatly Gauss, which approximately cor¬

responds to the intentai of 1 Ma.

Corrélations of régional magncrostracigraphic

schemes and composite petromagnetic columns

show, rhac nonvirhscanding rhe complété isola¬

tion of rhe Caspian and Euxinic basins in the

middle Pliocène, the Kimmerian tectonic activa¬

tion has simil.irlv aflectcd sedimentadon rhrough-

oLic the wholc of the eastern Para-Tethys.

In lhe north-rvestern Cis-Pontîc and Apsheron

régions, this is marked by the clear enough

petromagnetic effects in rhe sections through the

middle Kimmerian (orc) and the .Surakhan suite.

In Kercli Peninsula, western Georgia, Azerhaijan

and Turkmenia, an unconlormity séparâtes the

upper horizons ol the Kuyalnikian and

Actchagylian from the Kimmerian super-ore

sequence, .Surakhan and Cheleken suites; the

upper half of Gauss zone is not présent in the

section (Fig. 2).

Ail the aurhors analyslng lhe Pliocène history of

the Black Sea région, note ihc relative srability of

rhe Euxinic configuration and its cocrespondence

with the modem Black Sea area. It is only at

individual stages of the eastern Para-Tcthys évo¬

lution when large bays came into existence in the

Kuban-Azov Région and Guria (Kitovani 1976;

Nevesskaja É-r t//. 1986).

The limited latéral amplitudes of the Euxinic

484

GEODIVERSITAS • 1999 • 21 (3)

Pliocene évolution of Black Sea and Caspian basms

Saratov

Il I 1-1 F-*/ '

■..-..-.-.■.■^20

//—488

Volgograd

M I I

O* —

-O A ^577

f.MId

1 I I ir—

-^16

-f •---

- 29 CO^ .-

: OA.—•- —

11 . '7

O ostracods

Calcareous clays -

Maris and limestones

marine molluscs

non-manne

molluscs

A glauconite

• Wells

I I highiand plateau

• À o'i^ s g

Î 5 “.*’: 3 V, sands with pebbles

Fig. 6. — Lithological-palaeogeographical scheme of Actchagylian stage of the Caspian Dépréssion (Akhlestina & Karmishina 1973)

GEODIVERSITAS • 1999 • 21 (3)

Molostovsky E. A. & Guzhikov A. Yu.

transgressions with dominating plain savannah-

steppe landscapcs in the Cis-Poaiic Région

(Zubakov 1990) combined with the (hick trans¬

gressive sériés indicatc che tectonic quiescence in

the région and limited érosion ail ovcr the norch-

ern fringe of the Euxinic.

It follows from Figure 3, tbar the Pliocène trans¬

gressions were accumpanied by the changes Ln

the magnetic properties of corresponding sédi¬

ments. The amplitudes of pecromagnctic varia¬

tions thcmselves are insignificant, bccause only

the Lippcf, wcakiy magnctiscd horizons of the

sedimentary' cover hâve undergone érosion in the

sourceland. The large volcanic rnassif of the

Kara-Dag (southern Criniea) evidently did not

serve as a source area for the northern Euxinic

Basin in the Pliocène.

From palaeontological and lirhofacies data»

Kitovani (197 Cî) concliidcd, that ihe Kuyalnikian

âge represented the curning point in modem his-

tory of the Black Sca région, h corresponds to

the beginning of a major transgressive cycle that

should be considered as the start of the late

Pliocène.

This conclusion is supported by ail data, but the

basic importance of ihe Kuyalnikian (Actcha-

gyiian) stage for the évolution of the northern

fringes of the Tethys is not limited to the Black

Sca basins.

Palaeogeographic reconstructions show that the

Neogene history of the Para-Tethys is characteri-

sed by alternaring épisodes of isolation and réu¬

nification of iiidividual basiiu (Nevesskaya et ai

1986). Ail the géologie evenrs of that period,

accompaiiied by transgressions and régressions,

occurred in the sublatitiidinal direction berween

40 and 50 N; the northern margin of the Peri-

Tethys zone hardli ewer crosscd the conventional

line berween the présent Volga Delta and the

Taganrog Bay of the Azov Sea.

A fi-indamentally new geodynamic situation was

formed ai the beginning of the Acichagylian.

A number of large-scalc iransgrcssions bave resul-

ted in cardinal change of water-masses move-

ment direction, from the sublatitudinal to rhe

méridional one, A large brackish-watet basin ari-

sed in chc Ca-spLan Région: it sireiclied from ihe

Southern shores of che modem Caspian Sea for

more than 2000 km, right to the lower reaches of

the Kama River. This basin, nearly equal in its

area to rhe whole of rhe Para-Tethys, lasred

through the Apsheronian and disintegraied only

in the carly Picistocene due to a major Tjurkian

régression.

Faciès of the Upper Pliocène were studied in

derail in a number of papers (Kolesnikov 1940;

Ali-Zade 1954; Asadiilacv & Pevzner 1973;

Trubichin 1977), Coarsc-detrital sédiments from

5-10 to 50-60 mcircs ihick accumulatcd in litto¬

ral zones. Shallow-water sédiments were deposi-

ted ai modetate deprhs (down to 100 m); they

are represented by alternaring aleurolites and

sandstoncs up to 400 ni thick. Carbonates and

deep-water clays with aurhigcnic iron sulphides

(pyrites and greigites) were deposired in the cen¬

tral parts of the réservoir under the conditions of

hydrogen-sulphkle contamination Greigiie is

characteri.scd hy pronouriced fcrromagneiism

and to a large extent déterminés the magnetic

properties ol the Pliocène marine deposiis from

the northern Cis-Caspian.

‘Fhe faciès variations of Actchagyl northern Cis-

Caspian Basin arc analysed hy Akhlestina &

Karmi.shina (1973) (Fig. 6).

The structures ol the majority of the Cis-Caspian

Plioccnc scction-s studied in KaJmykia (well 13),

Saratov Région {w'clls 3, 20), clcarlv revcal sédi¬

mentation fhythms, causcd by alternating trans¬

gressive and régressive cycles. F.ach sédimentation

rhythm comprises arenaceous (régressive) and

argillaceous (iran.sgressivc) niembers with rhe

average rhicknes.s as of 30-50 m. Judgiiig from

the data publishcd, such a structure of the

Pliocène séquence is common for ihc whole of

the Volga and northern Cis-Caspian régions.

MineralogicaJ analyses hâve establislied that the

authigenic minerais pyrire-greigite association

characterise the transgressive sériés, while siderite

and iron hydroxides are characteristic of the

régressive ones. Transgressivc-fegressive sédimen¬

tation phases in petromagneiic columns are

registered by strong variations of scalar magnetic

characterisrics. ln che transgressive portions of

the elemental rhyrhms, Jn and k values vary,

basically* within rhe ranges of 20-150.10 -^ À/m

and 100-500.10 '' SI uniis. ln che régressive (are¬

naceous) faciès, dtey decrease to 0.5-10.10’^ À/m

and 10-30. lO'^-SI units.

486

GEODIVERSITAS • 1999 • 21 (3)

Pliocène évolution of Black Sea and Caspian basins

In some sections, composed of lithologically

homogcneou.s sequences or closely inrerUyered

rocks, magnetic parametrics becomes a more pré¬

cisé indicator of environmenraJ changes in rhe

deeper pans of die basin, ihan die iradicional

lirho-facies methods.

The available data do not allow the establish¬

ment of the total niimber of elemenral sédimen¬

tation rhychms within the Cis-Caspian

Actchagylian-Apsheroman sequence, since this

number may vary wiih the section completeness

and sédimentation conditions.

The comparative analyses oi petromagneiic data

from Wells 13 and 48 hâve revealed a quite clcar

corrélation between the compositions of spore-

pollen complexes and rock magnétisation.

Highiy magnetic transgressive portions of the

rliythms arc generally associated with the com¬

plexes of forest-steppe and forest types with the

content of arboreal pollen as high as 50-65% and

that ofherbaceous pollen notcxcecding 25-30%.

The wcakiy magnerised régressive faciès arc cha-

racterised by steppe palynocomplexcs dominated

by herbaccous pollen (Sedayein et ai 1987).

This indicates îhat the pctromagnetic characte-

risrics of the rocks, may niirrof the climatic

changes: alternations of rclatively hnmid warm

and cool arid periods.

The physical-mineralogic foundation of such

interrelations are quite évident. In the moments

of climatic opdma, favourable conditions are

created for production, drift and accumulation

of substanrial masses of plant organic matrer: the

burial of this matter gives rise to reducing condi¬

tions ncccssary to form auchigenic sulphides in

naiural silts. A.s il (ollows Irom the available data,

ihe transgressive phases in the Actcha^dian and

Apsheronian basins coincided with climatic opti-

ma.

The problem of corrélations between climatic

evcnis and sédimentation settings in the Plio-

Pleiscocene basins of the castern Para-Tcthys form

a long standing discussion. A wide range of ideas

bas been presented; various authors arrive at dia-

mctrically opposite conclusions on the basis ofvir-

tually similar data. Yakhimovich rt al. (1985)

correlate the Palaeo-Caspian transgressive stages

with the Plio-Pleisrocene climatic optima and ihc

régressive stages with the periods of cooling in the

Volga-Ural Région. Zubakov (1990), on the

contrary. asserted diat the Pliocène régressions of

the Caspian Sea are related with the thermo-

chrons, and the high stand srj^es - with cooling

and aridisation in the Cis-Caspian Région.

Fedorov (1978. 1982), in his studies of the

Pontic-Caspian palaeogcography, changed views

more than once.

Petroniagneiic data demonstrate, that the trans¬

gressive faciès of elemental rhythms are associa-

ted with thermochrons, and the régressive oncs

with cryochrons. There Is no support to correlate

large transgressive cycles with climatic optima,

bccause somc information bas been gained on

multiple vcgetation-community changes, and

consequently, on climacc oscillations throughout

each of the Pliocène rransgressions,

In the Ci.s-Cas'pian, Volga and Cis-Ural régions,

the period oftlie maximum middie Actchagylian

transgression coïncides with up to six changes of

climatic conditions rccordçd by corresponding

alternations of plant comnumities. Not less than

cight climatic oscillations are revealed in the

Apsheronian rime from palynological data: four

of rhem in the early and middie Apsheronian

and four at the end of the middie and in the laie

Ap.shertniian (Yakhimovich et al. 1985). On rhe

whole, al least fourteen climatic rearrangements

took place during the four transgressive-regressi-

ve cycles of the late Pliocène.

The origin of the great Caspian transgressions

présents one of the major problems in the

Plioccnc-Pleistocenc history of the P.ara-Terhys

and its northern burders. Tlie majority of the

authors relate them with water-balance changes

in the basin in response lo climatic change

(Fedorov 1978; Zubakov 1990). A number of

publications refer co the combined effects of tec-

tonic and Late Cainozoic climatic evencs

(Vostryakov 1973; Nevesskaya 1986).

One crucial aspect should bc considered whilc

discussing this problem. The Actchag)4ian vStage

in the évolution of the Pontic-Caspian was

accompanied by a major change in ihc outflow

System of between the Para-Tethys basins. A

sharp réduction of sublaiittidinaJ water-transfer

took place, and a stable System of gigantic méri¬

dional movements of water masses set up.

No events of such magnitude are possible

GEODIVERSITAS • 1999 • 21 (3)

487

Molosrovsky E. A. & Guzhikov A. Yu.

without large srructuraJ rearrangements of the

Earth cruîst, and the influence of thc tectonic fac¬

tor was probably décisive. Vostryakov (1973)

paid particular importance ro the régional neo-

tectonic rniwements in territorics of the Volga

and norrhern Cis-Caspian régions, but fails to

account for rhe Acrchagylian transgression to

western Turkmenia and the Aral Sea basin. It

may be possible that the changes of transgressive-

regressive cycles wcre controDed by the combina¬

tions ol oscillatory motions of tlïe Southern

Caspian dccp-watcr part and tlie Rtissian Plate

south-easLcrn periphery, the Peri-Caspian

Dépréssion included.

The dynamics oi the Pliocène transgressions,

cxemplifjcd by the mîddie Acrchag)Tan, may bc

assesscd as a first approximation magnetochrono-

logically through corrélation of régional palaeoma-

gnetic colamns, Trubikhin (1977) assigned the

beginning of rhe middle Actchagylian transgres¬

sion in Turkmenia to rhe middle ol Gauss cpoch

- ^3 Ma (above Kaen épisode). The northcin limit

of thc middle Aachagyl sédiments, corresponding

to the end oi Ciauss epoch ('-2.5 Ma), spreading is

established in well 3 nenr the city of Saratov.

Thus, during rhe Ü.4-Ü.5 Ma — long întcrvaJ, cor¬

responding to rlic second hall ol Gauss epoch, the

Actchagylian sea shore-line has shifted northwards

for more ihan 1500 km, which corresponds to the

average rate of 3 in per year.

CONCLUSION

Scalar magnetit characterisrics of rocks rcflect the

conditions of the sédimentation; ihis allows to

use petromagnetic data for palaeogeographic and

geodynamic rcconsiructions. Sharp changes in

sedimentary rock magneiLsaiioti serve as a direct

indication for increased tecionic activity within

source areas, resuking in new magnetic material.

In thc Lare Neogenc from thc Black Sea région, a

major peuomagnetic houndar>' i.s associated wirh

the Meotian/Pontian boundary.

An active input of magnetic material into the

marine basin proceeded since rhe Lare Pliocène,

culminating at the end of ihe Pliocène The

Paleogene dlusives of the Adjar-Triaict Ridge are

known to be the main source for the south-

eastern part of thc Euxinic Basin: the Ridge is

characrerised by stable uplilt foi at Ica-st 5.4 Ma

(since the start of Gilbert epoch to the présent).

Active uplifr uf rhe Main Ridge and. probably,

rhe Talysh Muunrains at thc castetn end of the

Cûucasus began as late as at thc end ol Gilbert

epoch and rcrminared in the early Gauss. The

Mcsozûic and Palacogene effusives consritticed

the source of the magnetic material rransported

to the Balakhan Basin.

The transgrcssivc-rcgrcssivc cycles in the Euxinic

and Caspian basins werc .signifîcantly difterent in

theu' magnitude. Phe Euxinic Basin did not

change its outline notably during the whole of

thc l*lio-Plci.stocene.

d'he Luxtnic Basin did not change its outline

notably during the whole ol the Pliocène, since

thc area cxieni of the incursions were rarher limi-

ccd. l’he Caspian transgressions, contrary to the

Black Sea ones, resultcd in thc création of vast

basins.

*rhc largesl of them, the middle Actchagylian

onc. extended lor more than 2000 km, from the

Southern margin of the Caspian Basin to the

Kama Rjver basin.

Acknowledgements

The authors arc grateful to Prof Van der Zwan

and Prof. J. Meiilenlcamp (Utrecht Universky,

the Nethedands) for iheir helpful reviews on the

finst draft of the paper.

REFERENCES

Abakshin O. V^, Bogachkin A. B. & Eremin V. N.

1993. — Palaeomagneric Section through the

‘'Bakinian srage” mountain: 119-126 |in Riissian],

problenh of the Pafeûztnc, J^^esoz4)ic and

Caifwzoii', hutr-(.oIIege scientifîc-papers eollecrion,

7'*' i.ssue. Saratov Universuy Publisncrs, Saratov.

Aklilesrinii E. f. iji Karmishina G. 1. 1973. — To the

problems of fades, sédimentation cyclicity and

stages ol Tpaerolauna] development in the Late

Pliocène from tlic Pcri-Caspian Dépréssion: 17-30

[in Russianj, w Vostiyakov A. V. (ed.), Ccfdogic

prohlems of the South Oral and Volga région. SG U

Publishcrs, Saratov.

Ali-Zade K. A. 1954. — The Aachagylian stage in

Azerbaijan. AzSSR AS Publishers, Baku, 334 p. [in

Russian].

488

GEODIVERSITAS • 1999 • 21 (3)

Pliocène évolution of Black Sea and Caspian basins

Ali-Zade A. A., Aleskerov D. A. & Pevzner M. A.

1973. — Palacomagneric study of the Pliocène

deposits from Apshcron Pcninsula; 10-13 [in

Russian], in Pevzner M. A. (ed.), Palaeomagnetic

analysis in studying the Qiiaternary deposits and vol-

canites. Nauka, Moscow.

Asadulayev li. M. & Pevzner M. A. 1973. —

Paleoniagnetism and biostratigraphy of the Late

Cenosoit beds. in rhe Kura Dépréssion: 6-10 [in

Russian], /« Pevzner M. A. (ed.), Palaeomagnetic

analysis in studytng the Qtiaîema}y deposits and voP

canites. Nauka, Moscow.

Fedorov P. V. 1978. — The Pontic-Caspian

Pleistocene, Nauka, Moscow, 165 p. [in Russian].

— 1982. — Soinc debatablc questions of the Black

Sea Pleistocene histor)^ MOÎP Bîdletin^ Geological

department 57 (1): 108-118 (in Russian],

Guzhikov A. Yu. & Molosiovsky E. A. 1995. —

Stratigraphie significance of scalai inagnctic charac-

teristics of sedimentar)' rocks (methodical aspect.s).

MOIP Bulletin^ Geological department 70 (l):

32-41 [in Russian].

Harland W. B., Cox A. V., Llewellyn P. Cî., Pickton

C. A. G-, Smith A. G. & Walters R. 1982. —

Geological tinte scale. Cambridge University Press,

Cambridge. 128 p.

Ismail-Zade T. A., Agamirzocs' R. A. & Geraibekov

E. A. 1967. — Magnctit properties and palaeoma¬

gnetic corrélation surnmary section of production

sériés of the Western Apsheron. Azerbaijanian oil

economy^: 1-4 [in Rus.sian].

Khramov A. N. 1963. — l^alaeomagnetic section of

the Pliocène and Pleistocene from Apsheron-Trans-

Caspian région and cheir corrélation: 145-174 [in

Russian], in Palaeomagnetic stratigraphie studies.

Gostoptcklii/dai, l^eningrad.

Kitovani T. G. 1976. — Gcochronologic importance

of the Late Plioccne and Early Pleistocene Cordidae

from Western Georgia. Sabehota Sakartvelo

Publication iTbilîsi, 154 p. [in Russian].

Kolesnikov V. P, 1940. — The Middle and LTppcr

Pliocène in the Caspian région. Stratigraphy of the

USSR, LISSR AS Publication, Moscow, Leningrad

12:407-476 [in Russian].

Molostovsky E. A. 1986. — Rock scalar niagnetic

characterustics as indicators of sédimentation condi¬

tions: 180-196 [in Russian], in Kumpan A. S.

(ed.), Rûch magnetism use in géologie survey. Nedra,

Leningrad.

Murarov M. V. & Nevesskaya L. A. 1986. —

Stratigraphy of the USSR, in Muratov M. V.

[çà.), The Neogene System. Volume 1. Nedra,

Moscow, 412 p. [in Russian].

Nevesskaya L. A., Goncharova L A., Ilyina L. B. et al.

1986. — The history of Neogene moHusks from the

Paratethys. Nauka, Moscow, 208 p. [in Russian].

Sedaykin V. M., Gonnov V. V., Kovalcnko N. D. et

al. 1987. — Référencé section of modem deposits

from the Noith-Wcsccrn Cis-Caspian. VINITL

N6095-V88, 38 p. [in Russian].

Trublkhin V. M. 1977. — Puleornagnetism and strati¬

graphy of the Actchagylian deposits in Western

Turkmenia. Nauka, Moscow, 79 p. [in Russian],

Vostryakov A. V. 1973. — Tectonic and climaric

conditions of forming of relief of South-East of the

Russian plain: 78-101 [in Russian], in Vostryakov

A. V. (ed.), Géologie prohlems ofthe South lirai and

Volga région. SG U Publishers, Saratov.

Yakhimovich V. L.. Bludorova E. A., Zhidovinov

N. Ya. et al. 1985. — Gcochronologic corrélation

of the Pliocène and Plei.sfocene géologie events in

the Volga-Ural région: 3-16 [In Russian], in

Yakhimovich V L. (ed.). Géologie events in the

Pliocène and Pleistocene history of Southern and

Northern seas. BF USSR AS, Ufa.

Zubalcov V. A. 1990. — Global climaric events m the

Neogene. Gidrometeoizdat, Leningrad, 220 p. [in

Russian].

Submitted for publication on 22 April 1997;

accepted on 30 June 1998.

GEODIVERSITAS • 1999 • 21 (3)

489

Instructions aux auteurs

La ligne éditoriale

Elle prendra en compte divers aspects de la

recherche en Sciences de la Terre, en paruculier

Thistoirc et le cornporicmcnt des bassins sédimen-

raires, la paléobiodiveisiré er les paléoenvironne-

mencs. Un numéro de Geodiversitas par an pourra

être consacré, excepTionnelIcmenr, au débat contra¬

dictoire sur un sujet d’actuaJiié, ou sur un thème

donné et sous In rcsponsabillcé d'cditcur(s) mvitc(s).

Les manuscrits, dont Je nombre de pages n'est pas

limite a priori, devront suivre rigoureusement les

recommandations aux auteurs (voir ci-dessous) et

seront adresses à la revue :

Service des Publications Scientifiques du Muséum,

GeodiversitaSj

57 rue Cuvier,

F-75231 Paris cedex 05

Tel : (33) 01 40 79 34 38

fax: (33) 01 40 79 38 58

e. mai! : bulletin@mnhn.fr

Les chapitres de systématique devront se conformer

aux règle.s du Code înternational de Nomenclature

Zoologique et du Code International de Nomen¬

clature Botanique.

Tout manuscrit non conforme à ces instructions

sera retourné pour mise au point. Chatjuc manus¬

crit est évalué par deux rapporteurs, ou plus.

Informations générales

Soumettre un article pour publication dans

Geodiversiun suppose que celui-ci ou tout article

proche dans la même langue ou une autre langue,

n'ait pas été soumis dans une autre revue, meme

dans Pattente de son acceptation. Les droits de

reproduction de l'article, y compris des illustra¬

tions, sont réservés k la revue. La reproduction de

tout ou partie de l’article doit faire l'objet d’une

demande écrite préalable adressée à la rédaction.

Chaque manuscrit soumis (y compris les illustra¬

tions) doit Etre présenté en trois exemplaires (un

original et deux copies) au formar A4, avec un

double inteiligne et des marges d'au moins 3 cm ;

chaque page seia numérotée. Les illustrations origi¬

nales seront jointes au manuscrit définitif, ainsi

qu’une disquette 3.5 " de format Apple Macintosh

ou compatible IBM (traitement de texte Word de

préférence), qui devra contenir également les

tableaux (Word, Excel, Dcncba Canvas, Adobe

Illustrator) et évcntucllenieni les illustrations

(Adobe Illustrator, Photoshop, format .EPS,

300 ppp maximum, à la dimension de la revue et

en police Helvetica, corps 8 ou 10).

Le format

Les manuscrits, écrits en français ou en anglais, doi¬

vent ctre structurés comme suit :

— titre si possible bref ; un titre courant doit être

proposé :

— traduction exacte du titre en anglais ;

— nom (s) et prénom(s) dc(s) nutcur(s) suivis de

leur(s) adrcssc(s) professioniitllc(s), en indiquant si

possible le numéro de télécopie cl l’adresse électro¬

nique ;

— résumés écrits en français et en anglais (800

signes au maximum chacun), suivis des mots clés et

« key words ;

— dans le texte courant, utiliser les italiques pour

tous les noms en latin : taxons de rangs générique

et spécifique (ex : CelLiria Ellis & Solander, 1786)

et al. ;

— dans le texte courant, les références aux auteurs

seront en minuscules, ex. Duponr (2001), Dupont

(2001, 2002), (Dupont 2001 ; Durand 2002),

(Dupont Durand 2003, 2005) Dupont (2001 r

1), Dupont (2001, fig. 2).

— dans le texte courant, les références aiLv illustra¬

tions et aux tableaux de l’article seront présentées

ainsi : (fig. 1), (Fig. 2A, D), (Fig. iA-C), (Figs 3,

6), (Figs 3-5), (Tableau 1) ;

— les remerciements seront placés à la fin du texte,

avant les références bibliographiques ; ils mention-

neronr les rapporteurs ;

— les références bibliographiques doivent suivre les

excmple.s donnés ci-dessous ;

— indiquer dans la marge l'emplacement des illus¬

trations dans le texte définitif ;

— donner les légendes des figures sur une feuille

séparée.

Les illtistrafions

Une atrenrion particulière sera portée à la qualité et

la pertinence de Fillustration.

Les illustrations au trait doivent être réalisées à

l’encte de Chine ou être fournies en impression

laser. Les photographies, bien contrastées, seront

GEODIVERSITAS • 1999 • 21 (3)

491

Instructions aux auteurs

sur fond noir ou blanc. Elles pourront être regrou¬

pées, et dans ce cas, identifiées pai une lettre en

capitales (A^ B, l es planches photogra¬

phiques. placées dans le corps de l’article et non

regroupées à la fui de celui-ci, doivent être traitées et

numérotées comme des figures. Le.s illustrations

pourront être assemblées sur une largeur de colonne

(70 X 190 mm) ou sur toute la largeur de la jusrifi-

cation (l44 x 190 mm). La réd-^etion encourage la

présentation de plioiugraphies avec tout ou partie

de leur interprétation par un ou des dessins au trait.

Aucune légende, ni lettrage ne sera placé sur les ori¬

ginaux. lU figureront .sur un calque joint avec

chaque figure, la rédaction se chargeant de les pla¬

cer. Chaque figure doit comporter une échelle

métrique, sans aucun coefficient multiplicaieur. Les

tableaux et graphiques^ à inclure dans le manuscrit,

doivent nécessairement pouvoir être imprimés sur

une page et rester lusibles après réduction éventuel¬

le. Des planches en couleur pourront être publiées

moyennant une parücipation financière de ou des

auteurs.

Références bibliographiques

Denison R. 11. 1978. — Placoderml. tn Schulize

H. P. (ed.), HfUidhook of Palcoichthyology,

Volume 2. Gustav Fischer, Stuttgart, 128 p.

Marshall C. R. 1987. — Lungfish: phylogeny and

parsimony, /w BeiiiLs W. E.. Burggren W. W.

& Kern P N, E. (edsj, The Biology and

Evolution of Lungfishes, lournal of Morphobgy

1: 151-162,

Schultze Fl. P. &C Arsenault M. 1985. — l'he pan-

derichthyid fish Elpistoste^e: a close relative to

tetrapods? }\tlet)riiolog}f 28: 293-309.

Schultze H. P. 1977a. — ’l he origin of the terra-

pod limb within ihc rhipidistian fishes;

541-544, in Flecht M. K., Goody P. C. &

Hecht B. C. (eds), Major Paiterra in Vertebrate

Evolution. Plen um Press, New York and

London.

Epreuves et tirés a part

Les épreuves seront adressées à l'auteur ou au pre¬

mier auteur (sauf indication contraire) et devront

être retournées corrigées sous huitaine. Les correc¬

tions, autres que celles imputables à la rédaction ou

à l'imprimeur, seront à la charge des auteurs. Le(s)

auteur(s) recevront gracieusement vingt-cinq tirés à

part, les lires à part supplémentaires .seront à com¬

mander sur un formulaire joint aux épreuves.

Scope of rhe Journal

publishcs papers which concern varied

aspects of R.irrh Sciences and parricularly hi.story of

sedimenrary bastns, pvtlaeobiodiversity and paleoen-

v^ironnienr. A complété issue of Geodiversitas may

bc de\^oted to scveral papers on a single topLc under

the tc.sponsabilliy ol gucsi cditor(s). Papers vy4th a

sysrematic content should fnllow rhe International

Code of y.otdogial Nomcntlatitre and the îuterna-

tiona! Code o/Botanical Notnenelawfc. Maiiusaipis.

without limitation of the iiun^ber of pages, niust

conform strictiy with the instructions to aurhors,

and wÜl be sent to the Lditor:

Service des Publications Scientifiques du Muséum,

Geoditfe7'sita.^y

57 rue Cuvier,

F-75231 Pari.s Cedex 05

Te! : (33) 01 40 79 34 38

Fax: (33) 01 40 79 38 58

e. mail : balletin@mnhn.fr

General information

The siihmis.sion of a nivinuscripi to Geodiversitas

implie.s ihat the paper, or a similar one, is not heing

offered for pubfic’ation clsewliere. C<îpyright of

published paper, incliiding rhe illustrations,

hccomes the property of ihc journal. Requests ro

reproduce matcrial from Geodiversitas should bc

addressed to ilic ediror.

Manuscriprs, with illu.strations, musr be submirted in

triplicate (une original and two copies) in A4 format,

double .spaccd, with margias of at least 3 cm and ail

pages numbered- The original figures should bc sent

with rhe revised manuscripi, as well as a 3.5" di.skette

Apple Macintosh or fBM-com[)atibie (Word) for¬

mat, which will aiso contain i.ible.s (Word, Excel,

Deneba Canva.s, Adobe llkistracor) and possibly

figuies (Adobe lllustraror, Phorctshop, -FJ'S format,

300 dpi maximum, in rhe page size of rhe ]onrnal

and with Helvetica font in 8- or lO-point body).

Format

Papers arc ro be written in simple and concise

Frencb or English. They should bc organized as fol-

lows:

-a brieftitle in English;

— a tille in French (exact translation);

-a suggested running head;

— name(s) of author(.s), followed by their full pro-

fessional addressfes) and. if possible, Fax number

and e.maih

— abstracts (in English and French) not exceeding

800 signs each, with key words and “mots clés";

492

GEODIVERSITAS • 1999 • 21 (3)

Instructions aux auteurs

— text with italicized words for Latin: taxa of gene-

ric and spécifie ranks (e.g. Cellaria Ellis &

Solander, 1786) et aL\

— référencés to authors In main text should be pre-

sented, in lower case, as follows: Smith (2001),

Smith (2001, 2002), (Smith 2001), (Smith 2001;

Cary 2002), (Smith & Cary 2003, 2005), Smith

(2001: 1), Smith (2001,%. 2);

— référencés to illustrations and tables should be

indicated as follows: (Fig. 1), (Fig. 2A, D), (Fig.

2A-C), (Figs 3, 6), (Figs 3-5), (Table 1);

— keep acknowledgements short and place them at

the end of che text before référencés; please do not

forget the revisers;

— give captions to illustrations on a separate sheet

and indicate their place in che margin.

Illustrations

The éditorial board will pay spécial attention to the

quality and relevance of illustration.

Line drawings musf be in Indlan ink or high quali¬

ty laser printouts; high contrast photographs, pla-

ced on white or black backgrounds, are required.

These can be grouped into figures and identified

by letters A, B, C ... Plates are not placed at the

end of the article: they will be considered as figures

and numbered as such. Arrange figures to fit onc or

mo columns (70 x 100 mm or 144 x 190 mm).

Associate interprétation of photograph with line

drawing. No diagram or table is to exceed one

page. Letters, numbers, etc., for each figure, are to

be indicated on an accompanying overlay, not on

the original figure (line eut or half-tone). A scale

bar is nceded for each figure (without magnifica-

tion factor).

Referetices

Denison R. H. 1978. — Placodermi, in Schultze

H. P. (ed.), Handbook of Paleoichthyologyy

Volume 2. Gustav Fischer, Stuttgart, 128 p.

Marshall C. R. 1987. — Lungfish: phylogeny and

parsimony, in Bemis W. E., Burggren W. W.

& Kemp N. E. (eds), The Biology and

Evolution of Lungfishes, Journal of Morphology

1: 151-162.

Schultze H. P. & Arsenault M. 1985- — The pan-

derichthyid fish Elpistostege: a close relative to

tetrapods? Paleontology 28: 293-309.

Schultze H. P. 1977a. — The origin of the tetra-

pod limb within che rhipidistian fishes:

541-544, /// Hecht M. K., Goody P. C. &

Hecht B. C. (eds). Major Patterns in Vertebrate

Evolution. Plénum Press, New York and London.

Proofs and reprints

Proofs will be sent to the First author for correction

and must be returned within eight days by express

mail. Authors will receive twenty-five offprints free

of charge; further offprints can be ordered on a

form supplied with the proofs.

GEODIVERSITAS • 1999 • 21 (3)

493

Mise en page

Noémie de la Selle

Packaging Éditorial

Achevé d’imprimer

sur les presses de l’Imprimerie F. Paillait

80100 Abbeville

Septembre 1999

N° d’impression : 10873

Printed on acid-free paper

Imprimé sur papier non acide

Date de distribution du fasicule 2, 1999 : 24 juin 1999

Couverture ; Alternances marnes-calcaires du Lias du Bassin Lombard (Alpes Méridionales)

Coupe des gorges de la Breggia (Suisse)

Photographie J. F. Deconinck (Université de Lille I)

geodiversitas

Peri-Tethys: stratigraphie corrélations 3

edited by Sylvie Crasquin-Soieau & Patrick De Wever

Crasquin-Soieau S. & De Wever P.

289 • Introduction

Gomankov A. V. & Burov B. V.

291 • Corrélations between Tatarian (Permian) type section (Russia) and the Sait Range (Pakistan)

palynology and palaeomagnetism

Kotiyar G. V., Baud A., Pronina G. P.^ Zakharov Y. D.,

Vuks V. Ja., Nestell M. K., Belyaeva G. V. & Marcoux J.

299 • Permian and Triassic exotic limestone blocks of the Crimea

Kukhtinov D. A. & Crasquin-Soieau S.

325 • Upper Permian and Triassic of the Precaspian Dépréssion: stratigraphy and palaeogeography

Vishnevskaya V. S., De Wever P., Baraboshkin E. Yu. et al. '

347 • New stratigraphie and palaeogeographic data on Upper jurassic to Cretaceous deposits from

the eastern periphery of the Russian Platform (Russia)

Guzhikov A. Yu. & Molostovsky E. A.

365 • Some features of the Early Cretaceous sédimentation in the Cis-Caucasia reflected in magnetic

properties of the sedimentary cover

Guzhikov A. Yu. & Eremin V. N.

387 • Régional magnetic zonality scheme for the Berriasian-lower Aptian from the North Caucasus

Kopaevich L. F., Alekseev A. S., Baraboshkin E. Yu. & Beniamovskii V. N.

407 • Cretaceous sedimentary units of Mangyshiak Peninsula (western Kazakhstan)

Radionova E. P., Khokhlova I. E. & Oreshkina T. V.

421 • Configuration of the Palaeogene deposits of Southern Russia

Khokhlova I. E. & Oreshkina T. V.

429 • Early Palaeogene siliceous microfossils of the Middie Volga Région: stratigraphy a

Khokhlova I. E., Radionova E. P., Beniamovskii V. N. & Sheherbinina E. K.

453 • Eocene stratigraphy of key sections of the Dnieper-Donets Dépréssion based on calcareous and

siliceous microplankton ^ ^

Molostovsky E. A. & Guzhikov A. Yu.

477 • Some peculiarities conceming the Pliocène évolution of the Black Sea and Caspian basins

Conception Graphique : Isabel Gautray

Publication trimestrielle, septembre 1999. ISSN : 1280-9659

Vente en France

Sales Office (France excluded)

Muséum national d'Histoire naturelle

Universal Book Services

Diffusion Delphine Henry

Dr. W. Backhuys

57, rue Cuvier, 75005 Paris,

PO. Box 321 2300 AH Leiden

France

The Netherlands

Tel. : 33 - 01 40 79 37 00

Tel. ; 31 71 - 517 02 08

Fax : 33 - 01 40 79 38 40

Fax : 31 71 -517 18 56

e-mail : dhenry@mnhn.fr

e-mail : backhuys@backhuys.com