Foraminifera assemblages in the Valaginian of the Polish Lowlands

R O C Z N I K P O L S K I E G O T O W A R Z Y S T W A G E O L O G I C Z N E G O A N N A L E S D E L A S O C l E T E G f i O L O G I Q U E D E P O L O G N E

T o m ( V o l u m e ) X X X I X — 1969 Z e s z y t ( F a s c i c u l e ) 1—3 K r a k ó w 1969

J A N IN A S Z T E J N *

FORAMINIFERA ASSEMBLAGES IN THE VALANGINIAN OF THE POLISH LOWLANDS

(7 Figs.)

Zespoły otwornic walanżynu na Niżu Polski

(7 fig.)

A b s t r a c t . S tu d ies of F o ra m in ifera a ssem b la g es w e r e carried out in the V a la n g in ia n of th e P o lish L o w la n d s in th e S zczecin —M ogiln o — Łódź trough, th e K u ja w y —P om orze S w e ll and th e m a rg in a l trou gh. On th e b asis of the lith o lo g ic a l an d m a cro p a la eo n to lo g ica l data of oth er authors, the V a la n g in ia n is d iv id ed into t h r e e subs'tages: th e L o w er, M id d le and U p per V a la n g in ia n . T h ree F o ra m in ifera a sse m b la g e s are d istin g u ish e d . P red o m in a n t gen era are Haplophragmoid.es, T r o c h a m - m i n a , and L e n t i c u l i n a in th e fir st a ssem b la g e, L e n t i c ul i n a and C i t h a ri n a in the se c o n d a ssem b la g e and L e n t i c u l i n a and E p i s t o m i n a in th e third assem b la g e. The p r e s e n c e o f p a rticu la r F o ra m in ifera a ssem b la g e s in th e se d im e n ts of th e P o lish L o w la n d s d epends a b ove a ll on the p roportion of sand.

IN T R O D U C T IO N

The purpose of the present account is to dem onstrate Foraminifera assem blages in the Valanginian.

These studies include the Szczecin—M ogilno—Łódź trough, the Ku­

jaw y— Pomorze S w ell and the m arginal trough 1 (tabl. I).

The results of these studies are based on m icrofauna from the follow ­ ing regions: Wiaderno, Łaziska, Dębniak, Sladków, Skotniki, M ierego- niew ice, Szpetal, Dąbrówka, Kukawy, Opoczki, Zakrzewo, Tuchołka, Ż ychlin, Strzelno, Oświno, Szam otuły, Mogilno, Niem ieczkowo, Dama­

sław ek, Kłecko, Pagórki, D ęby Janiszewskie, Kcynia, Koraczewko, Gro­

nowo, Chojnice, Stobno, M yśligoszcz, M odliszewko, Bolkowo, Bodzanów, M agnuszew, Żuromin, Gostynin, Lipno, Płońsk, Bielsk, Bieżuń, Iwiczna, Ciepielów, Sierpc, W arszawa, Przytyk, Dęba, Krzyżanowice, Dzierżanowo.

BSC. A. R a c z y ń s k a , Dr S. M a r e k and Dr J. W i t k o w s k i supplied the author w ith sam ples for m icropalaeontological analysis.

T hey also made available lithological profiles from the bore-holes studied and provided a considerable amount of inform ation, as to the strati­

* A d dress: D r J a n in a Szltejn, In sty tu t G eologiczn y , W arszaw a, ul. R a k o w ieck a 4, P o la n d .

1 T h e author em p lo y s th e d iv isio n in to tecto n ic u n its of th e area stu d ied after S . M a r e k and A. R a c z y ń s k a .

graphy, palaeogeography and macrofauna of the tectonic units studied by them. To these people, the author offers her gratitude. The author also thanks Prof. Dr O. P a z d r o w a , Prof. Dr F. B i e d a and Doc. Dr St. G e r o c h for constructive criticism during the w riting of the present account.

Foraminifera assem blages from sampled lithological profiles in par­

ticular tectonic units are show n in Figs. 2— 4. In the instance, where the w hole profile of the Valanginian is seen in one bore-hole, only this single bore-hole is figured. On the other hand, w here the entire Valan­

ginian profile is not seen in a single bore-hole, two or three bore-holes are shown together to give the com plete profile. In these figures, the quantitative composition of Foram inifera assem blages in particular sub­

p a g e s of the Valanginian is given, as w ell as occurrences of lam elli- branchs and am m onites in the sediments. The C aC 03 content of the sedim ents is also noted.

Because not all bore-holes in the regions m entioned are given in Figs. 2— 4, the list of Foram inifera from particular assem blages, contain­

ing only Foram inifera from the profiles included, w ould not be complete.

Therefore the author w ill also cite in the text Foram inifera found in other bore-holes, not given in the figures; thus the Foram inifera assem ­ blages given in the text w ill be complete. In Figs. 5— 7, the occurrence of Foraminifera assem blages in the Valanginian is given.

S T R A T IG R A P H Y

S . M a r e k (1961, 1967, 1968) and A . R a c z y ń s k a (1960, 1961, 1967) are carrying out studies of the Valanginian sedim ents of the Polish Lowlands. A. W i t k o w s k i studied the Lower Cretaceous of the Toma­

szów M azowiecki region. On the basis of lithology and amm onites, these authors distinguished the Lower, Middle, and Upper Valanginian in the area studied by them. The Lower Valanginian, or the zone w ith Pla t y- lenticeras sp., and the Upper Valanginian, or zone w ith Dichotomites sp., are characterized by marine sedim ents. On th e other hand, the Middle Valanginian (zone with Polyp ty ch ites sp.) was a period of shallow ing of the basin, with low ered salinity. The Lower Valanginian sedim ents form a continuation o f the Riazanian (Berriasian). It is possible to separate this stage from sedim ents of the Lower Valanginian in the P olish L ow ­ lands, m ainly on the basis of the ostracod Protocythere pseudopropria emslandensis B a r t . , B u r r i w hich occurs ch iefly in the Riazanian. The Upper Valanginian sedim ents gradually merge w ith those of Lower Hauterivian age. The separation of these two stages is very difficult in m any cases, because of lithological hom ogeneity and particularly w here identical Foraminifera assem blages are found in both sub-stages.

In Figs. 2— 4 are shown the lithological profiles sam pled in particular tectonic units. The low er boundary in these profiles, where it was possi­

ble to distinguish this, is the boundary betw een the Berriasian and Lower Valanginian.

L o w e r V a l a n g i n i a n — Wx — zone w ith Platylenticeras sp.

In the Lower Valanginian of the Szczecin—M ogilno— Łódź basin and in marginal basin, m ainly clays and som etim es sandy m arls are seen.

On the K ujaw y Sw ell, olays predom inate in >t'he sub-stage m entioned.

— 5.9 —

Fig. 1. M ap sh o w in g d istrib u tion of som e of th e m o re im p ortan t p ro files of the V a la n g in ian , in rela tio n to stru ctu ra l u n its of th e P o lish L o w la n d s, a fter S. M a r e k and A. R a c z y ń s k a . 1 — K iełp in o ; 2 — O św ino; 3 — M y śligoszcz; 4 — Stobno;

5 — C h ojnice; 6 — G ronow o; 7 — S za m otu ły ; 8 — N iem eczk o w o ; 9 — K cy n ia ; 10 — K oraczew ko; 11 — D a m a sła w ek ; 12 — K iecko; 13 — M od liszew k o; 14 — M o­

giln o ; 15 — T u ch ołk a; 16 — S trzelin ; 17 — P agórki; 18 — O poczki; 19 — M iereg o - n iew ie; 20 — O strow o; 21 — Z akrzew o; 22 — D ęby J a n isze w sk ie ; 23 — S zp etal;

24 — L ipno; 25 — Sierpc; 26 — K u k aw y; 27 — B ielsk ; 28 — P łoń sk ; 29 — D zierża- now o; 30 — B u lkow o; 31 — B od zan ów ; 32 — D ąb rów ka; 33 — G ostyn in ; 34 — Ż y ch ­ lin; 35 — S lad k ów ; 36 — S la zew o ; 37 — D ęb n iak ; 38 — W iaderno; 39 — Ł azisko;

40 — Iw iczn a; 41 — M agn u szew ; 42 — D ęba; 43 — P rzyty k ; 44 — K rzyżan o w ice;

45 — C iep ielów ; 46 — B ąk ow a; I — S zczecin — M ogilno— Łódź trough; II — K u ja ­ w y — P om orze S w ell; III — m a rg in a l trough

Szczecin— M ogilno— Łódź trough (Fig. 2)

In the Szczecin— M ogilno— Łódź trough x, A. R a c z y ń s k a described numerous lam ellibranchs and fairly scarce am m onites in the Lower Valanginian.

1 T h e p resen t account in clu d es on ly th e resu lts of stu d ies of F o ram in ifera fou n d in th e S zczecin and M ogilno 'troughs. In the Ł ódź trough, stu d ie s are as y e t in ad eq u ate.

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Foraminifera are very scarce in the Szczecin trough. Here w ere found Glomospirella gaultina ( B e r t h.), Trochammina inflata ( M o n t a g u), Haplophragmoides cushmani L o e b . , T a p., Lenticulina subalata ( R e u s s).

There is an abundant m icrofauna in the Mogilno trough and, as seen from the species given below, in the Szczecin and Mogilno troughs, an assem blage of agglutinating Foram inifera predominates. In these, the species chiefly represented are: Haplophragmoides cushmani L o e b . , T a p.*, Haplophragmoides C *, Haplophragmoides D *, Haplophragmoi­

des B. Besides the forms m entioned above, in this assemblage, specim ens belonging to the follow ing species are found: Trochammina inflata ( M o n t a g u ) and Trochammina kcyniensis S z t e j n ***.

Fairly scarce specim ens of calcareous Foram inifera belong to the species:

Lenticulina subalata ( R e u s s), Vaginulinopsis humilis ( R e u s s), Eogut- tulina witoldi S z t e j n ** and Epistomina caracolla anterior B a r t . , B r a n d . *

K ujaw y Sw ell (Fig. 3)

In the Lower Valanginian of the K ujaw y Sw ell. S. M a r e k confirmed the presence of Platylenticeras sp., as w ell as of numerous lam ellibranchs.

Abundant Foraminifera were also found in sedim ents of this age.

In the N.W. part of this ridge (Kiełpino region), single specim ens of Glomospirella gaultina ( B e r t h.) occur. Further to the N.E. of the ridge (Kcynia region), Foraminifera are abundant and agglutinating spec­

ies, such as the follow ing predom inate: Haplophragmoides cushmani L o e b . , T a p.,** Haplophragmoides concavus (C h a p.), Trochammina inflata ( M o n t a g u ) , Trochammina kcyniensis S z t e j n,*** Lagenammi- na difflugiformis ( B r a d y), Glomospirella gaultina ( B e r t h.). R elatively few calcareous Foraminifera w ere found and among these are Lent icu­

lina subalata (R e u s s) and *Eoguttulina witoldi S z t e j n.

In the northern part of the K ujaw y Sw ell, the same assem blage as on the Pomorze S w ell (Tuchołka and Zakrzewo regions) is found. The agglutinating Foram inifera m entioned above occur in the central part of the K ujaw y S w ell (Żychlin and Śladków) and, in addition to these, there are fairly numerous calcareous Foraminifera: Lenticulina subalata ( R e u s s), Astacolus diversicostatus (L i s z k a), Vaginulinopsis humilis ( R e u s s), Eoguttulina witoldi S z t e j n,** Globulina prisca ( R e u s s).

On the S.W. flank of the K ujaw y Sw ell, in the Tomaszów region (Ła­

zisko, Tomaszów Maz.), calcareous Foram inifera predom inate (Fig. 3) in the Lower Valanginian sedim ents: Citharina pseudostriatula B a r t . , B r a n d ***, Citharina intumescens (R e u s s) ***, Citharina duestensis ( B a r t . , B r a n d ) ***, Citharina orthonata ( R e u s s), Lenticulina nodosa ( R e u s s), Lenticulina subalata ( R e u s s), Lenticulina muensteri ( R o e m.), Vaginulinopsis humilis ( R e u s s), Astacolus diversicostatus (L i s z k a), Epistomina cf. o m a t a T e n D a m , Epistomina cf. cretosa T e n D a m , Epistomina tenuicostata B a r t . , B r a n d . On the other hand, among

* In d e x sp e c ie s o f F o ra m in ifera for t h e L o w er V a la n gin ian .

** In d e x sp ecies of F o ra m in ifera fo r th e R ia zan ia n , L o w er and M id d le V a lan g in ian .

*** A n in d e x sp e c ie s o f F o ra m in ifera for th e R iazan ian and L ow er V a la n gin ian .

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agglutinating Foraminifera, only scarce specim ens of the follow ing spec­

ies were found: Verneuilinoides neocomiensis (M j a 1 1.), Haplophrag- moides convacus (C h a p.), Glomospirella gaultina ( B e r t h.), Ammoba- culites subcretaceus C u s h . , A l e x . , Trochammina depressa L o z o.

The presence of two Foram inifera assem blages was confirm ed in the Lower Valanginian sedim ents on the K ujaw y—Pomorze Sw ell. In one of these, representatives of the follow ing species of Foram inifera predo­

minate: Haplophragmoides convacus ( Ch a p . ) , Haplophragmoides cush- mani L o e b., T a p., Trochammina inflata ( M o n t a g u ) , Trochammina kcyniensis S z t e j n. In this assembladge, there are also found calcare­

ous Foraminifera, such as: Lenticulina subalata (R e u s s), Astacolus diversicostatus ( L i s z k a), Eoguttulina witoldi S z t e j n, V aginulinopsis humilis ( R e u s s). In the second assemblage, species of calcareous Fora­

minifera predominate: Citharina pseudo str iatula B a r t . , B r a n d , Ci- tharina orthonata ( R e u s s), Lenticulina nodosa ( R e u s s), Lenticulina subalata ( R e u s s), Vaginulinopsis humilis ( R e u s s), Astacolus d i v e r ­ sicostatus (L i s z k a), Conorboides valandisensis ( B a r t . , B r a n d).

Agglutinating Foraminifera occur sporadically in th is assem blage and are represented by: Haplophragmoides concavus (C h a p.), Verneuili- noides neocomiensis (M j a 1 1.), Ammobaculites subcretaceus C u s h . , A l e x . , Trochammina depressa L o z o.

Marginal trough

This includes the Pomorze, Warszawa and Lublin troughs. In the marginal trough (Fig. 4), the presence of the Lower Valanginian is noted in the Pomorze and Warszawa troughs only. Sedim ents of this age are absent from the Lublin trough.

S. M a r e k found scarce remains of Platylenticeras sp. and lam elli- branchs in the Lower Valanginian of the marginal trough. Foraminifera

are scarce in sedim ents of this age.

In the N.W. part of the Pomorze trough, where sedim ents of this age are distinguished on the lithological and m acropalaeontological prem ises, single specim ens o f Glomospirella gaultina ( B e r th.) were found. Further to the S. in this trough specim ens of the follow ing Foraminifera species were found: Glomospirella gaultina ( B e r th.), L en­

ticulina cf. muensteri ( Ro e m. ) , Trochammina inflata ( M o n t a g u ) , Lenticulina subalata ( R e u s s).

In the Lower Valanginian of the Warszawa trough, scarce specim ens were found: Ammobaculites cf. subcretaceus C u s h . , A l e x . , Trocham­

mina inflata (M o n t a g u), Trochammina kcyniensis S t e j n *, Lagenam- mina difflugiformis ( B r a d y), Lenticulina subalata ( R e u s s), Haplo­

phragmoides convacus (C h a p.), Globulina prisca ( R e u s s), Eoguttulina witoldi S z t e j n **, Verneuilinoides neocomiensis (M j a 1 1.). There is an im poverishm ent of the scarce m icrofauna in an easterly direction.

Thus in the Lower Valanginian sedim ents of the marginal trough, a Foraminifera assemblage occurs, in w hich representatives of agglutin­

ating species predominate: Haplophragmoides concavus ( Ch a p . ) , Tro ­ chammina inflata ( M o n t a g u ) , Trochammina kcyniensis S z t e j n and Lenticulina subalata (R e u s s). Other species of Foram inifera are rarely encountered.

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M i d d l e V a l a n g i n i a n — W2 — zone w ith Polypt ychite s sp.

In the Szczecin—M ogilno—Łódź (Fig. 2) and Pomorze troughs, the Middle Valanginian (Fig. 4) occurs as fine-grained sandstones w ith interbedded shales and marls in places. On the K ujaw y— Pomorze Sw ell (Fig. 4) and adjacent Warszawa trough (Fig. 4), there are also sandy sedim ents w ith larger inclusions of shales and marls at the top the base.

In the remaining part of the marginal trough (Fig. 4), shales and marls with subordinate interbedded sandstones were deposited in the Middle Valanginian.

In the Middle Valanginian of the Szczecin— Mogilno—Łódź trough and on the K ujaw y S w ell, no ammonites, only lam ellibranchs were found. No index fauna has been confirmed in the m arginal trough.

Foraminifera are scarce in the Middle Valanginian of the Polish Lowlands and m ay be found w ith some d ifficulty in sm all am ounts in the marl or shale interlayers. In the Szczecin—Mogilno— Łódź trough, Foraminifera were found only sporadically in marls in the part adjacent to the K ujaw y Sw ell (Ślazewo region). On the K ujaw y Sw ell, Foram i­

nifera w ere found in the lower, silty part of the Middle Valanginian (in the regions of Kcynia, Żychlin, Śladków). In the part of the m arginal trough, adjacent to the K ujaw y Sw ell, Foraminifera occur as on the K ujaw y Sw ell in the low er part of the Middle Valanginian. In the re­

m aining part of the trough, where silty sedim ents predominate in a Middle Valanginian of reduced thickness, Foraminifera are found in the w hole com plex of sedim ents.

The follow ing Foram inifera species were found in the Middle Valan­

ginian: Glomospirella gaultina ( B e r t h . ) , Haplophragmoides conoavus ( Ch a p . ) , Haplophragmoides cushmani L o e b . , T a p.,*4 Ammobaculites subcretaceus C u s h . , A l e x . , Trochammina inflata ( M o n t a g u), L e n ­ ticulina subalata ( R e u s s), Vaginulinopsis humilis ( R e u s s), Globulina prisca ( R e u s s). These are the forms most com m only occurring in the Lower Valanginian. In the Middle Valanginian over the w hole of the Polish Lowlands, there is a Foraminifera assemblage, in which G lom o­

spirella gaultina ( B e r t h.), Haplophragmoides concavus (C h a p.) and Lenticulina subalata (R e u s s) are found fairly frequently.

U p p e r V a l a n g i n i a n — W3 — zone w ith Dichotomites sp.

In the Upper Valanginian of the Szczecin—M ogilno—Łódź trough, shales and marls w ith subordinate sandy interlayers were deposited. On the K ujawy Sw ell sedim ents of this age are also seen as shales. In the marginal trough sandy marls and shales, w ith interlayers of organo- detrital and oolitic lim estone in the S.E. part, w ere laid down during the Upper Valanginian.

Szczecin— Mogilno—Łódź trough

In the Szczecin—Mogilno— Łódź trough (Fig. 2), A. R a c z y ń s k a did not find am m onites in the Upper Valanginian; here only lam elli­

branchs were found.

In the Upper Valanginian sedim ents, as in the Lower Valanginian, relatively few Foraminifera were found.

Foraminifera are very scarce in the Szczecin trough. In the Upper

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Valanginian of this trough (Oswino region), on ly single specim ens of Lenticulina subalata (R e u s s), Vaginulinopsis humilis (R e u s s) and Glomospirella gaultina ( B e r t h.) w ere found; on the other hand, no representatives of the genus Epistomina w ere encountered. It is difficult to speak of the existence of any kind of Foraminifera assem blage, since they occur sporadically.

In the M ogilno trough, Foram inifera are more abundant; among agglutinating Foraminifera, the follow ing were found: Glomospirella gaultina ( B e r t h.), Ammobaculites subcretaceus C u s h . , A l e x . , Tro­

chammina inflata ( M o n t a g u ) , Haplophragmoides concavus (C h a p.).

Besides these, here there are species of calcareous Foraminifera:

Epistomina caraaolla caracolla ( R o e m.) ****, Epistomina cretosa T e n D am ****, Epistomina tenuicostata B a r t . , B r a n d . , Lenticulina suba­

lata (R e u s s) and Lenticulina muensteri ( R o e m.).

K ujaw y— Pomorze Sw ell (Fig. 3)

In the Upper Valanginian of the K ujaw y— Pomorze Sw ell, S. M a r e k found a rich macrofauna, com prising num erous specim ens of lam elli- branchs and amm onites, w hich latter are index form s for this sub-stage.

In the N.W. part of the Pomorze ridge (Kiełpino region), Foraminifera are represented by single specim ens of Glomospirella gaultina ( B e r t h.) only. Upper Valanginian sedim ents are absent in the S.E. part of this Sw ell.

An abundant microfauna is found in the Upper Valanginian of the K ujaw y Sw ell. On the N.E. flank of the northern part of the K ujaw y S w ell (the Kabat and Toporzysko regions), Foram inifera occur in sm all quantities. The more im portant species among these are: Epistomina caracolla caracolla ( R o e m.) ****, Epistomina ornata T e n D a m ****, Lenticulina subalata (R e u s s), Lenticulina muensteri (R o e m.), Vagi- nulinopsis humilis ( R e u s s).

To the S.E. of the K ujaw y Sw ell (Żychlin, Ślazewo region), Foram i­

nifera occur in greater quantities. There are the follow ing species:

Epistomina caracolla caracolla ( R o e m.) ****, Epistomina cretosa T e n D a m ****, Epistomina ornata T e n D a m ****, Lenticulina subalata ( R e u s s), Lenticulina muensteri ( R o e m.), V aginulinopsis humilis ( R e u s s ) , Marginulina pyramidalis Ko c h, * * * Citharina seitzi B a r t . , B r a n d.,**** Astacolus cephalotes ( R e u s s), and single specim ens of Haplophragmoides concavus (C h a p.), Ammobaculites subcretaceus C u s h . , A l e x .

As shown above, the follow ing species are particularly abundant in the Upper Valanginian sedim ents of the K ujawy Sw ell: Epistomina ca­

racolla caracolla ( R o e m.), Epistomina cretosa T e n D a m , Epistomina ornata T e n D a m , Lenticulina subalata ( R e u s s), Lenticulina m u e n ­ steri ( R o e m.), Citharina seitzi B a r t . , B r a n d .

Marginal trough (Fig. 4)

In the Pomorze trough, Foram inifera are found only sporadically.

U p to now, a few specim ens of Lenticulina subalata ( R e u s s ) have

**** In d ex sp ecies of F o ra m in ifera -for th e U p p er V a la n g in ia n and L ow er H a u te r iv ia n .

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been distinguished w ith difficulty (Chojnice region). In the W arszawa trough, numerous Foram inifera of the follow ing species w ere found:

Glomospirella gaultina ( B e r t h.), Am m o b acuities subcretaceus C u s h . , A l e x . , Lenticulina muensteri ( R o e m.), Vaginulinopsis humilis ( R e u s s), Marginulina pyramidalis K o c h ****, Epistomina caracolla caracolla ( R o e m.) ****, Epistomina cretosa T e n D a m ****, Epistomina tenuicostata B a r t . , B r a n d . , Conorboides hofkeri ( B a r t . , B r a n d.).

In the Lublin trough, few Foraminifera have been found in Upper Valanginian sediments; these include: Lenticulina nodosa ( R e u s s), L e n ­ ticulina subalata ( R e u s s), Lenticulina muensteri ( R o e m.), Vaginuli­

nopsis humilis ( R e u s s), Epistomina caracolla caracolla (R o e m.) ****, Epistomina cretosa T e n D a m ****.

An im poverishm ent of the m icrofauna in the N.E. direction is seen in the Warszawa and Lublin troughs. Two Foraminifera assem blages may be distinguished in the Upper Valanginian of the m arginal trough.

The assemblage in the Warszawa trough comprises the species: G lom o­

spirella gaultina ( B e r t h.), Ammobaculites subcretaceus C u s h . , A l e x . , Haplophragmoides convacus (C h a p.), Lenticulina muensteri ( R o e m.), Vaginulinopsis humilis ( R e u s s), Marginulina pyramidalis K o c h , Epi­

stomina caracolla caracolla ( R o e m.), Epistomina ornata T e n D a m Conorboides hofkeri ( B a r t . , B r a n d). This is clearly a m ixed assem ­ blage. In this assemblage, representatives of the follow ing species pre­

dominate: Lenticulina muensteri ( R o e m.), Epistomina caracolla cara­

colla ( R o e m.), Epistomina ornata T e n D a m . Here also occur scarce representatives of species of agglutinating Foraminifera.

In the Lublin trough, there is another Foram inifera assem blage. Here agglutinating Foram inifera are rare, and the follow ing species of cal­

careous Foram inifera chiefly occur: Lenticulina muensteri ( R o e m .) , Epistomina caracolla caracolla ( R o e m.) ****, Epistomina cretosa T e n D a m ****, Conorboides hofkeri B a r t . , B r a n d .

C H A R A C T E R IST IC S OF F O R A M IN IF E R A A S SE M B L A G E S OF TH E PO L ISH L O W L A N D S A N D TECTONIC U N IT S

As seen from considerations given in the previous section, sim ilar Foraminifera assem blages do not occur in all regions in the P olish Low ­ lands. On the sketch maps (Fig. 5— 7), the exten ts of particular sub- -stages of the Valanginian, after S. M a r e k and A. R a c z y ń s k a (1967), are shown. On these maps, the extents o f the Foram inifera assemblages are also shown. Areas w ith particular sub-stages of the Valanginian and lyin g beyond the reach of the Foraminifera assem blages, have not been studied up to now in terms of microfauna.

On Fig. 5, the extents of occurrence of Foram inifera assem blages are related to the Lower Valanginian sedim ents. In the sedim ents of this sub-stage, there is a Haplophragmoides-Trochammina-Lenticulina assemblage, called by the author a s s e m b l a g e I. This is characterised by the presence of the follow ing species: Haplophragmoides concavus ( Cha p. ) , Haplophragmoides cushmani L o e b . , T a p . , Haplophragmoi­

des B, Haplophragmoides C, Haplophragmoides D, Trochammina inflata ( M o n t a g u ) , Trochammina kcyniensis S z t e j n, Lenticulina subalata ( R e u s s). In this assem blage, there m ay be certain quantitative and

O ST R O W O (1/1)

F ig. 3. O c c u rre n c e of F o r a m in if e r a in sa m p le d b o re - h o le s of th e K u ja w y -—P o m o rz e rid g e . 1 — s h a le s ; 2 — sa n d s, s a n d s to n e s ; 3 — m a r ly s h a le s ; 4 — g ra v e ls ; 5 — lith o lo g y i n t e r p r e te d on b a sis o f g e o p h y s ic a l m e a s u r e m e n ts in b o re - h o le ; a — 1— 4 s p e c im e n s ; b — 5— 10 s p e c im e n s ; c — 1.1—30 sp e c im e n s ; d — 31— 60 sp e c im e n s ; e — 61— 100 s p e c im e n s ; + — + H C 1 ; — = —H O I; L — L e d a ; A r — Area; A s — A s t a r t e ; E — E x o g y r a ; P — P i n n a ; T — Tr i g o n ia ; C — C orb u la ; P e — P e c te n ; P p — P o l y p t y c h i t e s p e t s c h o r e n s i s ( B o g ) ; A — A s t i e r i a ; L e — L e o p o ld i a sp .; G — G r a m m a t o d o n ; P m — P o l y p t y c h i t e s cf. m i c h a l s k i i ( B o g .) ; D — D i c h o t o m i t e s bi- d i c h o t o m u s ( L e y m . ) ; E n — E n d e m o c e r a s n o r i c u m ( R o e m . ) ; P o — P o l y p t y c h i t e s sp .; P k — P o l y p t y c h i t e s cf. k e y s e r l i n g i ( N e u m . , U h l . ) ; V j — L o w e r V a la g in ia n ( P l a t y le n t ic e r a s zone); V2 — M id d le V a la n g in ia n (P o l y p t i c h i t e s zone); V3 — U p p e r V a la n g in ia n (D ic h o t o m i t e s zone); H — H a u te r i v ia n ; T — T e r ti a r y ; Q — Q u a te rn a r y .

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F ig . 2. O c c u rre n c e of F o r a m in if e r a in s a m p le d b o r e - h o le s of th e S z c z e c in —M o g il­

n o — Ł ó d ź tr o u g h . 1 — shal&s; 2 — sa n d s , s a n d s to n e s ; 3 — m a r ly s h a le s ; 4 — s id e r ite s ; 5 — g ra v e ls , c o a r s e - g r a in e d s a n d s to n e s ; 6 — s a n d y lim e s to n e s ; 7 — s tig m a r ia ; 8 •— s id e r ite ; b .r. —■ a b s e n c e of c o re ; a .— 1— 4 s p e c im e n s ; b — 5— 10 sp e c im e n s , c — 11— 30 s p e c im e n s ; d — 31— SO s p e c im e n s ; e — 61— 108 s p e c im e n s;

+ — + H C 1 ; — = — H C l; P t — P o l y p t y c h i t e s sp. (t a r d is c i s s u s K o e n e n ); A s — A s t a r t e ; T r — T e r e b r a t u l a ; O — O s t r e a ; E — E x o g y r a ; L — L e d a ; G — G r a m m a - to d o n ; V] — L o w e r V a la n g in ia n ( P la t y le n t ic e r a s zone); V ? — M id d le V a la n g in ia n ( P o l y p t y c h i t e s zone); V 3 — U p p e r V a la n g in ia n (D i c h o t o m i t e s zone); H — H a u te -

r iv ia n . L i'th o lo g ical p ro f ile a f t e r A, R a c z y ń s k a

— 65 —

qualitative variations. This depends upon the part of the tectonic unit from w hich the Foraminifera assem blage under consideration comes.

In the Baltic zone of the Pom orze Sw ell and Pomorze trough, the presence of several single specimens of Glomcspirella gaultina ( B e r t h.) was detected in Lower Valanginian sedim ents, recognized on the basis of lithology and macrofauna. To the S .E., both in the Pomorze and Szczecin Troughs, in addition to the Glomospirella gaultina ( B e r t h.), scarce specim ens of the follow ing are also found: Haplophragmoides con- cavus ( Ch a p . ) , Haplophragmoides cushmani L o e b . , T a p . , Trocham- mina inflata ( M o n t a g u ) , Lenticulina subalata ( R e u s s). In the S. part of the Pomorze Sw ell, the N. and central part of the K ujaw y S w ell, as w ell as the adjacent part of the Warszawa trough, numerous Foram inifera species m ay be distinguished: Haplophragmoides concavus ( Ch a p . ) , Haplophragmoides cushmani L o e b . , T a p., Haplophragmoides B., Ha­

plophragmoides C, Haplophragmoides D, Trochammina inflata (M o n- t a g u), Lenticulina subalata ( R e u s s), and Glomospirella gaultina ( B e r t h.), Ammdbaculites subcretaceus C u s h . , A l e x., Vaginulinopsis humilis ( R e u s s), Astacolus diversicostatus (L i s z k a), Conorboides va-

F ig. 5. R an ge of occu rren ce fo r F o ra m in ifera assem b la g es of th e L ow er V a la n g in ia n of th e P o lish L ow lan d s (distrib u tio n of th e L o w er V a la n g in ia n a fte r A. R a c z y ń ­ s k a and S. M a r e k ) . 1 — areas w ith o u t L o w er V a la n g in ia n e p ico n tin e n ta l s e ­ d im en ts; 2 — sh a les; 3 — sh a les and m arly sh a les, o c c a sio n a lly san d y; sc a le h orizon tal; 4 — d irectio n in w h ich sa n d -o o n ten t of se d im e n ts d ecreases; 5 — lim it o f ranges fo r F o ra m in ifera a ssem b la g e s; 6 — lim it of e x te n t of L o w er V a la n g in ia n sed im en ts; I — H a p l o p h r a g m o i d e s - T r o c h a m m i n a - L e n t i c u l i n a a ssem b la g e of F o ra­

m in ifera ; II — L e n t i c u l i n a - C i t h a r i n a a ssem b la g e of F o ra m in ifera

5 R o c z n ik G e o lo g ic z n y t o m X X X I X

— 60 —

lendisensis B a r t . , B r a n d . Thus here is a typical Haplophragmoides- -Trochammina-Lenticulina assemblage.

In the E. part of the Warszawa trough, there is a poorer microfauna;

m any species known from the K ujaw y S w ell are not found in the E. part of the W arszawa trough. Among the m ore com m only occurring Fora- m inifera species found here are: Haplophragmoides concavus ( Ch a p . ) , Trochammina inflata ( M o n t a g u ) , Lenticulina subalata (R e u s s).

On the S.W. flank of the K ujaw y Sw ell, the place of the Haplophrag­

moides-Trochammina-Lenticulina assemblage is 'taken by another Fora- m inifera assemblage. This latter is the Lenticulina-Citharina assem blage, called by the author, a s s e m b l a g e II, and characterised by the pre­

dominant species: Lenticulina subalata ( R e u s s ) , Lenticulina nodosa ( R e u s s), Lenticulina muensteri ( R o e m.), Citharina orthon^ata ( R e u s s), Citharina rudicostata B a r t . , B r a n d., Citharina pseudostriatula B a r t . , B r a n d . A gglutinating Foram inifera are represented by Verneuilinoides neocomiensis (M j a 1 1.), as w ell as scarce specim ens of Trochammina depressa L o z o, Haplophragmoides concavus (C h a p.), Glomospirella gaultina ( B e r t h.).

There exists an interdependence betw een the distribution of particular Foraminifera species in the Lower Valanginian sedim ents of the Polish Lowlands and th e,d ecrease in sand-content of these se d im e n ts1. The further to the S.E. and S. the sedim ents, the low er the sand-content and the greater the number of species and specim ens of Foraminifera. Gra­

dually towards the S.E., the number of species of calcareous Foram inifera increases, so that these constitute alm ost the entire thanatocoenosis in the Tomaszow M azowieoki region.

A comparison of distributions of Foraminifera species, in the Lower Valanginian of the Polish Lowlands in a W.-E direction, gives interesting results, A gglutinating Foram inifera predominate in the Mogilno trough.

On the K ujaw y Sw ell and adjacent part of the m arginal trough, the proportions of agglutinating and calcareous Foram inifera are more or less equal. In the E part of the Warszawa trough, agglutinating Fora­

minifera again predominate. This fact m ight perhaps be explained by the presence of a higher sand-content in the sedim ents of the Mogilno trough and especially in the E part of the Warszawa trough. On the K ujaw y Sw ell, where the shaly sedim ents are less sandy, there is a greater number of Foraminifera species and, at the same time, the number of species of calcareous Foraminifera increases to the extent that they make up about half of the w hole assemblage.

On Figs. 2— 4, the C aC 03-content of the sedim ents is given 2. As seen in all cases the Lower Valanginian sedim ents of the Polish Lowlands are not calcareous. Thus, in the Lower Valanginian, there is no possi­

bility of proving a relationship betw een the presence or a b s e n t of certain Foraminifera species and the lim e-content of the sediments.

1 T h e sam p les receiv ed by th s author for m icro p a la eo n to lo g ic a l a n a ly sis had alrea d y been siev ed . T hus it w a s n et p o ssib le for the author to stu d y the sa n d - -co n te n t of th e sed im en ts. T h e author b ases the con sid era tion relatin g to the d ecrease in p ercen ta g e quartz in th e sed im en t on the data of S. M a r e k and A. R a c z y n s k a .

2 T he author uses data on C aC O --con tent o f 'the se d im e n t; after S. M a r e k and A. R a c z y n s k a .

— 67 —

On Fig. 6 is shown the occurrence of Foraminifera in relation to the sedim ents of Middle Valanginian age. In the sedim ents of this sub-stage, Foraminifera are scarce and belong to the Haplophragmoides-Trocham- mina-Lenticulina assemblage. The follow ing species occur: Haplophrag- moides concavus (C h a p.), Haplophragmoides cushmani L o e b . , T a p., Trochammina inflata ( M o n t a g u ) , Lenticulina subalata ( R e u s s), Glo- mospirella humilis gaultina ( B e r t h.), Vaginulinopsis ( R e u s s), Eogut- , tulina voitoldi S z t e j n.

The occurrence of Upper Valanginian Foram inifera in relation to sedim ents is given in Fig. 7. In the sedim ents of this sub-stage, a L e n ti ­

culina-Epistomina assem blage is found. This assem blage is termed by the author a s s e m b l a g e III. The Lenticulina-Epistomina assem blage is characterized b y t'he presence of: Lenticulina subalata ( R e u s s), L e n ­

ticulina muensteri ( R o e m.), Epistomina caracolla caracolla ( R o e m.), Epistomina cretosa T e n D a m , Epistomina tenuicostata B a r t . , B r a n d . The list of species making up the Lenticulina-Epistomina assemblage m ay require alterations. This assem blage m ay display certain variations. These are slight qualitative and quantitative variations, de-

Fig. 6. R an g e of occu rren ce fo r F ora m in ifera a ssem b la g es of the M id d le V ala n g in ia n of th e P o lish L o w la n d s (d istrib u tion of 'the M id dle V a lan g in ia n based on data of A. R a c z y ń s k a and S. M a r e k ) . 1 — fin e -g r a in e d san d ston es, w ith su b o rd in a te co a rse-g ra in ed san d ston es; 2 —■ san d sto n es w ith p ock ets of rh izoidal, m arly sh a les;

3 — sh ales and m a rly sh ales; 4 — sa n d sto n es at top and base w ith silty and m a rly sh a le pock ets; 5 — areas w ith o u t V a la n g in ia n e p ico n tin e n ta l sedim en'ts; 6 — lim it of range for F ora m in ifera a ssem b la g e; 7 — lim it of e x te n t of V a la n g in ia n sed im en ts;

8 — direction in w h ich sa n d -c o n te n t of sed im en ts decreases; I — H a p l o p h r a g m o i d e s - - T r o c h a m m i n a - L e n t i c u l i n a a ssem b la g e of F oram in ifera ; sca le h orizon tal

5 ‘

— 68 —

pending on the part of the tectonic unit, from which the Foraminifera assem blage under consideration comes.

In the N.W. part of the Pomorze Sw ell (Trzebiatów synclinorium , for exam ple, in the Kiełpino region) only a few specim ens of Glomospirella gaultina ( B e r t h.) were found. In the Szczecin and Pomorze troughs, scarce specim ents of the species Lenticulina subalata (R e u s s) and V aginulinopsis hum ilis (R e u s s) w ere found. Only in the M ogilno trough do agglutinating Foraminifera occur in fairly large quantities. These are Ammobaculites subcretaceus C u s h . , A l e x . , Haplophragmoides con- cavus (C h a p.), Trochammina inflata ( M o n t a g u ) . Agglutinating Fora­

m inifera are rare in the rem aining part of the Polish Lowlands, occupied by Upper Valanginian sedim ents. In the Mogilno trough, besides those species mentioned above, the follow ing species, scarce but characteristic for the Lenticulina-Epistomina assemblage, were found: Lenticulina s u ­ balata ( R e u s s), Lenticulina muensteri ( R o e m.), Epistomina cretosa T e n D a m , Epistomina tenuicostata B a r t . , B r a n d , Epistomina ca- racolla caracolla (R o e m.).

On the other hand, in the central part of the K ujaw y Sw ell and the adjacent part of the W arszawa trough, numerous specim ens of the

•Lrl-Li

.- - - - I 1 2 ₆

Fig. 7. R an ge of occurrence for F o ra m in ifera assem b la g es of th e Uipper V a la n g in ia n of th e P o lish L o w la n d s (d istrib u tion of th e U p per V a la n g in ia n b ased on data of A. R a c z y ń s k a and S. M a r e k ) . 1 — sh a les and m arly sh a les, in p la c es sandy;

2 — sh ales and m arly sh a les w ith pookets of m a rly , organodetri'tal and oolitic lim esto n es; 3 — areas w ith o u t U p per V ala n g in ia n e p ico n tin e n ta l sed im en ts; 4 — 'd ir e c tio n in w h ic h s a n d -c o n te n t of se d im e n t decreases; 5 —• d irectio n in w h ic h lim e -c o n te n t of sed im en ts in crea ses; 6 — lim it of ran ge of F o ra m in ifera a ssem b la g e;

7 — lim it of e x te n t of U p per V a la n g in ia n sedim en'ts; III — L e n t i c u l i n a - E p i s t o m i n a a ssem b la g e of F oram in ifera

— 69 ^—

follow ing species were found: Lenticulina subalata ( R e u s s), Lenticulina muensteri ( R o e m.), Epistomina caracolla caracolla ( R o e m.), Epistomina cretosa T e n D a m , V aginulinopsis humilis ( R e u s s), as w ell as very scarce specim ens of Haplaphragmoides concavus (C h a p.), Am m obacu- lites subcretaceus C u s h . , A l e x .

In the N. part of the K ujaw y Sw ell and adjacent part of the W arsza­

wa basin, hardly any agglutinating Foram inifera w ere found and cal­

careous forms occur alm ost exclusively: Lenticulina subalata ( R e u s s)r Lenticulina muensteri ( R o e m.), Epistomina caracolla caracolla ( R o e m.)r Epistomina cretosa T e n D a m . Likewise, there is an absence of agglu­

tinating Foraminifera in the Lublin trough, where only Lenticulina su­

balata ( R e u s s), Lenticulina muensteri ( R o e m.), Lenticulina nodosa ( R e u s s), V aginulinopsis humilis ( R o e m), Epistomina caracolla cara­

colla ( R o e m.), and Epistomina cretosa T e n D a m are found.

In the Upper Valanginian of the Polish Lowlands, as in the Lower Valanginian, there is an interdependence betw een the distribution of particular Foraminifera species and the direction of decrease in sand- -content of the sedim ents. The sedim ents become less sandy in a S.E.

and S direction. With decrease in sand-content of the sedim ents, th e number of species and specim ens of Foraminifera increases. The number of species of calcareous Foram inifera increases gradually in a N.W.— .

—S.E. direction. In the Lublin trough, these species constitute practically the entire thanatocoenosis.

A comparison of the distribution of Foram inifera species in the Upper Valanginian of the P olish Lowlands, from W. to E., gives interesting results. A gglutinating Foram inifera are relatively abundant in the Mo- gilno trough, w hile in the central part of the K ujaw y Sw ell, th ey are partly replaced b y calcareous forms and are practically absent from the Warszawa trough. This phenom enon m ay be explained as resulting from a slight increase in the carbon content of the sedim ents from W. to E.

C O N C LU SIO N S

The data given above show that several conclusions m ay be drawn on the basis of the vertical and horizontal distribution of Foram inifera in the Valanginian.

In the P olish Lowlands, the presence of a large number of Foram i­

nifera species, of wide stratigraphic range, has been dem onstrated. B e­

sides these, there is a certain number of index species. In the Lower Valanginian, the follow ing are index species: Haplophragmoides B, Ha- plophragmoides C, Haplophragmoides D, Epistomina caracolla anterior B a r t . , B r a n d . Eoguttulina witoldi S z t e j n and Haplophragmoides cushmani L o e b . , T a p. are index species for the Riazanian and Lower and Middle Valanginian. For the Riazanian and Lower V alanginian Tro- chammina kcyniensis S z t e j n is an index form. Index species for the Upper Valanginian and Lower H auterivian are: Epistomina caracolla caracolla ( R o e m.), Epistomina cretosa T e n D a m , Epistomina ornata T e n D a m , Citharina seitzi B a r t . , B r a n d . , Marginulina pyramidalis

K o c h .

In the Valanginian sediments, three Foraminifera assem blages m ay be recognized: I — a Haplophragmoides-Trochammina-Lenticulina

— 70 —

assem blage in the Lower and Middle Valanginian, II — a Lenticulina- -Citharina assem blage in the Lower Valanginian and III — a Lenticulina-

-Epistomina assem blage in the Upper Valanginian.

In the Valanginian of the Polish lowlands, the presence of particular Foraminifera species in the sedim ents depends prim arily on the sand- -content. In sandy sedim ents, Foram inifera are absent. As the sand- -content of the shales and marls decreases, progressively more species of calcareous Foraminifera appears; in sedim ents w ith a low sand- -content, calcareous Foraminifera predominate.

Ge ol ogic al I n s t i t u t e T r a n s l a t e d

W a r s z a w a B a r ba r a M a r sz a l — F r a nk S i m p s o n

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— 71 ^—

STR ESZC ZEN IE

W opracowaniu niniejszym przedstawiono zespoły otwornic w alan- żynu na Niżu Polski. Badania objęły sw ym zasięgiem nieckę szczecińsko- -m ogileńsko-łódzką, w ał kujawsko-pom orski, nieckę brzeżną. Przedsta­

wiono zespoły otwornic na tle w ybranych profilów litologicznych. Stra­

tygrafia walanżynu została opracowana na podstawie danych litologicz­

nych, makro- i m ikrofaunistycznych. Dane m akrofaunistyczne i lito lo ­ giczne czerpano od A. R a c z y ń s k i e j i S. M a r k a . Wśród badanych otwornic wyróżniono trzy zespoły: I — haplófragm oidesowo-trocham ino- w o-lentikulinow y, II — lentikulinow o-citarinow y i III — lentikulinow o- -epistom inow y. Obecność poszczególnych gatunków otwornic w w ym ie­

nionych zespołach może ulegać pew nym wahaniom, zależy to od tego, z jakiej części jednostki tektonicznej pochodzi rozpatryw any zespół otwornic. Wahaniom może również ulegać ilość okazów otwornic w po­

szczególnych gatunkach. W w alanżynie na Niżu Polski obecność poszcze­

gólnych gatunków otwornic w osadzie jest uzależniona przede w szystkim od stopnia zapiaszczenia. W miarę zwiększania się stopnia zapiaszczenia iłow ców i m ułowców pojawia się coraz mniej gatunków otw ornic w apien­

nych, w osadach o nieznacznym stopniu zapiaszczenia dominują otw or- nice wapienne. W ęglanowość osadów ma również w pływ na w ystępo­

wanie poszczególnych gatunków otwornic. W miarę zwiększania się w ę- glanow ości osadów pojawia się większa ilość otwornic wapiennych.

W całym walanżynie na Niżu Polski w ystępuje stopniowo w kierunku z północnego-zachodu na południow y wschód coraz w ięcej gatunków otwornic, a także wzrasta liczebność okazów. Porównanie rozmieszczenia otwornic w w alanżynie dolnym w kierunku z zachodu na wschód daje ciekawe w yniki. W niecce szczecińsko-m ogileńsko-łódzkiej oraz w e wschodniej części niecki w arszawskiej dominują otwornice zlepieńcow a- te.. Natom iast na w ale kujaw skim i w przylegającej do niego części niecki brzeżnej ilość gatunków otw ornic w apiennych i zlepieńcow atych jest mniej w ięcej równa. W w alanżynie górnym, w kierunku z zachodu na wschód zanikają otwornice zlepieńcowate. W w alanżynie na Niżu Polski obok licznych otwornic o dużym zasięgu stratygraficznym stwierdzono pewną ilość form przewodnich.

I n s t y t u t G eo l o g i c z n y W a r s z a w a