Dinoflagellate cyst biostratigraphy of the Late Jurassic of Poland : [Biostratigraphie des kystes de dinoflagellés du Jurassique supérieur de Pologne] = Biostratigraphie des kystes de dinoflagellés du Jurassique supérieur de Pologne

OF T H E LATE J U R A S S I C OF P O L A N D

NIEL E. P O U L S E N

POULSEN N.E. 1994. Dinoflagellate cyst biostratigraphy of the Late Jurassic of Poland. [Biostratigraphie des kystes de Dinoflagell~s du Jurassique sup~rieur de Pologne]. GEOBIOS, M.S. 17 : 401-407.

ABSTRACT

Polish Upper Jurassic dinoflagellate cyst assemblages have been examined from outcrop and borehole samples and related to the Standard ammonite zonation for the area. These dinoflagellate cyst association have been correlated to corresponding associations in D e n m a r k and the British Isles. In general this correlation suggests a stratigra- phic range for the dinoflagellate cyst biozonation similar to those established for the British Isles and Denmark. The Oxfordian sections yielded dinoflagellate cyst associations that are different in composition from those of the Danish Subbasin, the North Sea area, and the British Isles. The Kimmeridgian and Volgian dinoflagellate cyst associations of Poland are very rich, and comprise m a n y species described from the North Sea area together with many other species. In the Kimmeridgian, however, the boundary between the Stephanelytron scarburghense

Subzone and the Perisseiasphaeridium pannosum Subzone occurs in the middle Divisum Zone. In the British Isles, this boundary corresponds to the middle Mutabilis Zone. The boundary in Poland is marked by first or last occurrences of four of the index species, allowing possible correlation of the middle Divisum Zone with the middle Mutabilis Zone. The uppermost Volgian beds of the Holy Cross Mountains-Krakow-Wielun area are dated as Scythicus Zone and are marked by dinoflagellate cyst species, which indicate the Dichadogonyaulax culmula Zone, Subzone a and a possible correlation to the Albani Zone.

KEY-WORDS : POLAND, LATE JURASSIC DINOFLAGELLATE CYST, CORRELATIONS.

RI~SUMI~

Les assemblages de kystes de Dinoflagell6s du Jurassique sup6rieur de Pologne : nt 6td examines en 6chantillons de coupes et sondages datds par ammonites. Les associations de kystes de Dinoflagell6s ont 6td correl6es avec des associations correspondantes au D a n e m a r k et en Grande-Bretagne. G6n6ralement, la corr61ation indique que les r6partitions ressemblent beaucoup ~ celtes du D a n e m a r k et de Grande-Bretagne. Les associations oxfordiennes sont diff6rentes de celles du Sous-bassin Danois, de la Mer du Nord et de Grande-Bretagne. Les associations kimm6ridgiennes et du Volgien de Pologne sont tr~s riches et comprennent, entre autres, beaucoup d'esp~ces d6crites en Europe du Nord-Ouest. Mais dans le Kimm6ridgien la limite entre les sous-zones ~ Stephanelytron scarburghense et ~ Perisseiasphaeridium pannosum est plac6e dans la partie moyenne de la zone ~ Divisum. En Grande-Bretagne, cette limite est placde au milieu de la zone h Mutabilis. En Pologne, la limite est marqude par l'apparition ou la disparition de quatre-esp~ces index, ce qui rend possible une corrdlation entre la partie moyenne de la zone ~ Divisum et celle de la zone ~ Mutabilis. Le Volgien le plus sup~rieur de Pologne central, dat6 de la zone h Scythicus est marqu~ par des espbces de kystes de Dinoflagell6s qui indiquent la zone h Dichadogonyau~ax culmula, sous-zone a, et une correlation avec la zone h Albani est possible.

MOTS-CLI~S : POLOGNE, KYSTES DE DINOFLAGELLI~S DU JURASSIQUE SUPI~RIEUR, CORRI~LATIONS.

INTRODUCTION

D i n o f l a g e l l a t e c y s t s f r o m a m m o n i t e - d a t e d s a m p l e s f r o m t h e U p p e r J u r a s s i c o f P o l a n d w e r e s t u d i e d d u r i n g a r e s e a r c h p r o j e c t c a r r i e d o u t du- r i n g 1988-1990. T h e p u r p o s e of t h e project w a s to i n v e s t i g a t e t h e a p p l i c a t i o n of t h e J u r a s s i c dino- f l a g e l l a t e c y s t b i o z o n a t i o n c u r r e n t l y u s e d for Bri- t i s h s e c t i o n s to t h o s e of t h e D a n i s h S u b b a s i n . D i n o f l a g e l l a t e cysts f r o m a m m o n i t e - d a t e d s a m p l e s f r o m t h e U p p e r J u r a s s i c of P o l a n d w e r e s t u d i e d d u r i n g t h e p r o j e c t to p r o v i d e c o r r e l a t i o n a n d f u r t h e r b i o s t r a t i g r a p h i c control of t h e D a n i s h d i n o f l a g e l l a t e c y s t z o n a t i o n to o t h e r

biostratigraphic zonations besides the British Is- les.

The dinoflagellate cyst biozonation established by Davey (1979, 1982), Woollam & Riding (1983), Nchr-Hansen (1986), Riding & Thomas (1988) and Poulsen (1991a) have been applied to the studied Polish material. (See also Poulsen, herein).

AMMONITE BIOZONATION

The Oxfordian ammonite zonation and correla- tion in the Boreal-Subboreal subprovince, the northwestern European subprovince, and the Submediterranean province is given in Sykes & Surlyk (1976) and Sykes & Callomon (1979). The ammonite zonation for the Submediterranean province, given by Sykes & Callomon (1979), is used for the Polish subprovince.

The precise stratigraphical correlation from the Submediterranean province to the Boreal Realm of the Oxfordian-Kimmeridgian boundary is diffi- cult (e.g. Sykes & Callomon 1979). The stratigra- phic position of the Oxfordian-Kimmeridgian boundary is discussed in Birkelund & Callomon (1985, p. 15-19) and by Birkelund (in Aarhus et al. 1989, p. 53). Recently Matyja & Wierzbowski (1988) correlate more conclusively the submedi- terranean Planula Zone with the Baylei Zone, the lowermost zone of the boreal Kimmeridgian. The ammonite scheme used for the Lower Kim- meridgian of the Polish subprovince, is the Sub- mediterranean zonation. The four zones, Planula, Platynota, Hypselocyclum and Divisum Zones correspond to the Baylei and Cymodoce Zones of the Subboreal province.

The zonation for the Upper Kimmeridgian of the Polish subprovince is similar to the Subboreal zo- nation.

The correlation of the Lower Volgian zones be- tween the Volga Basin, including the Polish subprovince, and the Subboreal province has not been established. The boundary between the Lo- wer-Middle Volgian of the Volga Basin and the Polish subprovince is doubtfully placed at the top of the Tenuicostata Zone (Callomon & Birkelund, 1982). Even more tentative is the correlation of the Middle Volgian Zones (Callomon & Birkelund 1982 ; Callomon, personal commun. 1989).

MATERIAL

Material was studied from Polish outcrops and boreholes in the Holy Cross Mountains and their

in A m m o n i t e z o n e s Scythicul Tenuicoatata Pseudoscythicl S o k o l o v l K t l m o v l Autlssiodorensis Eudoxus Mutabllls D l v i s u m Hypsslocyclum Platynota P l s n u l a B l m i m m m l u m , ~ Blfurcatus T r s n s v e t s a r l u m 0 PIIcaIIIIs C o r d a t u m Mariae L a m b e r l I Athletl g ~ • o , = i = ~ =o ~=o=. _. - 0 = m o =: - z ~ f ~ co . q [ m m N 1 g ' - " :=:= m = o t I : ~ .~ _== o o u ) o > , ? ~. , _ I 15 I Outcrops ~ Boreholss A 1oo K r n - L . / " "

Figure 1 - A. Stratigraphic extent of the Polish sections stu- died. Numbers below sections are the locations shown on Fig. lB. B. Map of Poland showing t h e locations of t h e sections studied. N u m b e r s refer to the sections locations on Fig. 1A. No. 16 is the three boreholes Barcin-Pakosc 3, Barcin-Pakosc 16 and Barcin-Pakosc C-42. A. extension stratigraphique des coupes polonaises dtudides. Les numdros sous les coupes indi- quent la position gdographique prgcisde Fig. lB. B. Carte gdo- graphique simplifide du secteur d'dtude. Les numdros indi. quent la position des coupes de la Fig. 1A. No. 16 correspond aux trois sondages Barcin-Pakosc 3, Barcin-Pakosc 16 et Bar. cin-Pakosc C-42.

flanks, the KrakSw-Weilun upland, and the east- ern part of the Pomeranian Trough. Some of the information concerning the deposits and the con- tent of macrofossils in the Polish localities is

found in K u t e k (1968), Kutek & Zeiss (1974), Ma- tyja (1977), M a t y j a & Wierzbowski (1981), and Wierzbowski (1978). The details of the Polish samples are given in Poulsen (1989). The geogra- phical and stratigraphical positions of the locali- ties are shown in Fig. 1. The was prepared follo- wing the preparation method of Poulsen

et al.

1990.

Samples from the two overlying subzones of the B i m a m m a t u m Zone were unfortunately unpro- ductive and the precise top of Subzone e is not identified. However, t h e B i m a m m a t u m Zone is now regarded as the uppermost Oxfordian Zone, and the identification of Subzone c within this level suggests isochrony of this subzone from Po- land to England.

D I N O F L A G E L I A T E C Y S T B I O S T R A T I G R A P H Y

Most of the studied samples from the Upper J u - rassic of Poland were rich in dinofiagellate cysts, except for some of the Oxfordian-Lower Kimme- ridgian samples, which were unproductive, proba- bly due to weathering, (only productive zones are discussed below). All the samples were collected with reference to the S t a n d a r d ammonite zona- tion for the area.

OXFORDIAN

The Oxfordian is characterized by dinoflagellate cyst assemblages different in composition from those in the Danish subbasin, North Sea area and the British Isles, i.e. with other species domi- nating the assemblages (see below). These species may be present in the areas northwest of Poland, but only infrequently.

T r a n s v e r s a r i u m Z o n e

The oldest assemblage identified is from the T r a n s v e r s a r i u m Zone. It contained a b u n d a n t

Epi-

plosphaera

sp. and

Gonyaulacysta eisenackii. The

occurrence of both

Compositosphaeridium poloni-

cure

and

Glossodinium dimorphum

allows a cor- relation to the

Scriniodinium crystallinum

Zone, Subzone a.

The identification of this subzone in the Trans- versarium Zone, which mainly corresponds to the Tenuiserratum Zone (Boreal-Subboreal subpro- vince) (Sykes & Callomon 1979 ; Callomon, perso- nal commun. 1989) indicates an isochronous de- velopment of this subzone.

B i m a m m a t u m Z o n e

The lower subzone, the H y p s e l u m Subzone, also contained a b u n d a n t

Epiplosphaera

sp., but

G. ei-

senackii

occurs only infrequently.

Gonyaulacysta

jurassica jurassica

occurs frequently.

Ctenidodi-

nium ornatum

and

Occisucysta balia

are present, which indicates the

S. crystallinum

Zone, Subzone c (the latter, however, only doubtfully identified).

KIMMERIDGIAN

The Kimmeridgian samples produced v e r y rich assemblages with m a n y species in common with the assemblages from the Danish Subbasin, the North Sea area and the British Isles. Especially the dinoflagellate cyst flora of t h e

Endoscrinium

luridum

Zone in Poland is very rich, containing m a n y of the species described from the North Sea area. Also many species described from other part of Europe e.g.

Amphorula metaeUiptica, At-

lantodinium

jurassicum,

Protobatioladinium

westburiense,

and Australia, e.g.

DoUidinium si-

nuosum

were recognized in this stage.

The flora is rich in

Subtilisphaera? inaffecta

and

Subtilisphaera? paeminosa,

which in the Danish Subbasin and the Skagerrak - K a t t e g a t platform area are only common near the Baltic Shield (Skagen-2 and S o u n d - l a boreholes). In England

Subtilisphaera?

sp. are also infrequent (Riding, personal commun. 1990) as they are in the Cen- tral Trough.

Some of the stratigraphic index species differ in abundance compared with the Danish subbasin and the Skagerrak-Kattegat platform area cr the British Isles.

Nannoceratopsis pellucida

and

Scri-

niodinium crystallinum

are not recorded in this s t u d y in the Kimmeridgian of Poland.

G. jurassi-

ca jurassica

which is a common species in the la- test Oxfordian, is a b u n d a n t in the Planula-ear- liest Hypselum Zones, and it is common to the end of the Kimmeridgian of Poland, where it disappears. It should be noted t h a t it is only a local last occurrence d a t u m for this species. In the Danish and British areas it occurs in the Lo- wer Volgian, whereas in more northerly localities, it occurs in the later parts of the Volgian (Poul- sen 1991b).

Dichadogonyaulax chondra

is present from the base of the Kimmeridgian and almost to the top of the Jurassic in Poland.

P l a n u l a Zone

The first occurrence of

D. chondra

is found wi- thin this zone. Zotto

et al.

(1987) described the first appearance of this species to be in the Baylei Zone. The first occurrence of this species

E N G L A N D STAGES A M M O N I T E Z O N E S Kerberus Okusensls Glaucolithus Albani Fittoni Rotunda Pallasioides Pectinatus Hudlestoni Wheatleyensis Scitulus Elegans P O L A N D STAGES Autissiodorensis Eudoxus Mutabilis Cymodoce Baylei Rosenkrantzi Regulare Serratum G l o s e n s e Tenuiserratum Densiplicalum Cordatum ? Zarasjkensis S c y t h i c u s Scythicu ? e- ra O . . . w Tenuicostata O > P s e u d o s c y t h i c ~ Sokolovi - - Klimovi ~ - ? C ° ~ Divisum "E H y p s e l o c y c l u m E . . . E Platynota Planula B i m a m m a t u m Bifurcatus e,. Transversarium o Plicatilis x O Mariae D I N O F L A G E L L A T E ZONES FAD C Y S T b Dc a ?e ?d c Gd b a Pp El Ss ? ?d c ? Sc b a ? I D. culmula D. pannea __J O. patulurn

~____~

P. pannosum S.? paemlnOSa (common S.? inaffecta (common) . ~ C.? Iongicorne _ _ ~ D. chrondra [ O. balia _ _ } G. dimorphum LOD - - - 7 S. inritibile "-~i G. dimorphum O. balia O. palulum - ~ ] S.? inaffecla ----~ E. luridum G. iurassica S.? paeminosa - - ] E. galeritum - - I S. scarburghense ] G. eisenackii C. ornatum I C. polonicum

F i g u r e 2 - C o r r e l a t i o n c h a r t for t h e L a t e J u r a s s i c s u c c e s s i o n s in P o l a n d a n d in boreal a r e a s . C o r r e l a t i o n of t h e S c y t h i c u s Zone in accordance w i t h c o n c l u s i o n s from t h i s s t u d y . F A D : F i r s t a p p e a r a n c e d a t u m s . L O D : L a s t o c c u r r e n c e d a t u m s . Corrdlations dans le Jurassique supdrieur entre le sectcur polonais et /e domaine bordal. Corrdlation de la zone dz Scythicus selon les conclusions de l'gtude. F A D : Premibre apparition. L O D : Derni~re prdsence.

in the Polish subprovince supports the correlation of the Planula Zone to the Baylei Zone. The last appearance of

G. eisenackii

is found in the Planu- la Zone. According to Sarjeant (1979) its last ap- pearance is in Baylei Zone. Together with the ab- sence of

C. ornatum

this indicates the

S. crystal-

linum

Zone, Subzone d.

H y p s e l o c y c l u m Zone

The first occurrence of

Cribroperidinium? longi-

corne

allows a correlation to the

E. luridum

Zone (there is in this s t u d y no record of dinoflageltate cysts from the underlying P l a t y n o t a Zone). In En- gland this is equivalent to the base of the Cymo- doce Zone.

Stephanelytron scarburghense,

the

index species of the

S. scarburghense

Subzone, is present.

G. jurassica jurassica

is common, but less common t h a n in t h e zones below.

D i v i s u m Z o n e

The b o u n d a r y b e t w e e n t h e

S. scarburghense

Subzone and the

Perisseiasphaeridium pannosum

Subzone is m a r k e d b y t h e last occurrence of S.

scarburghense

and the first a p p e a r a n c e of

P. pan-

nosurn, S. paeminosa

and c o m m o n

Subtilisphae-

ra? inaffecta

; this b o u n d a r y is recorded in the middle Divisum Zone. In t h e B r i t i s h Isles, this stratigraphic level corresponds to t h e middle Mu- tabilis Zone ( N 0 h r - H a n s e n 1986 ; Poulsen 1991a).

This event is recorded in Wierzbica, Malogoszcz Quarry and Szadkowice boreholes. The middle Divisum Zone is believed to correlate with the middle Mutabilis Zone.

Mutabilis Zone

This zone is not Characterized by the appearance or disappearance of dinoflagellate cyst species, except for the last occurrence of

Epiplosphaera

gochtii

at t h e top of the zone.

Subtilisphaera?

sp. is less common t h a n in the underlying Divisum Zone or in the overlying Eudoxus Zone.

valent to the

Glossodinium dimorphum

Zone, Subzone a.

Within the Klimovi Zone the first appearance of

Oligosphaeridium patulum

and

Dichadogonyau-

lax pannea

is found. In E n g l a n d both species oc- cur in the Upper Kimmeridgian.

S o k o l o v i Z o n e

Endoscrinium anceps, Endoscrinium pharo and

Gochteodinia mutabilis

make their first appea- rance in this zone.

E u d o x u s Zone P s e u d o s c y t h i c a - T e n u i c o s t a t a Z o n e s

Endoscrinium galeritum

disappears at the base of the zone.

S.? inaffecta

is common from the base to the middle of t h e zone, whereas S. ? pae-

minosa

is common for the first time in the middle of the zone.

P. pannosum

is also very common in the middle of the zone.

A u t i s s i o d o r e n s i s Zone

The base of t h e zone is m a r k e d by the first occur- rence of

Oligosphaeridium pulcherrimum

and the common occurrence of

G. jurassica jurassica. The

l a t t e r species is not recorded above this level in Poland.

S.? paeminosa

disappears at the top of the zone, whereas

S. ? inaffecta

is very common.

Endoscrinium luridum

disappears at the top of the Autissiodorensis Zone, indicating t h a t the top of the

E. luridum

Zone is isochronous from En- gland to Poland.

Volgian

Most of the Volgian samples also produced rich assemblages with high diversity (about 40 - 60 species per sample). Most species recorded, how- ever, occur in low numbers of specimens, except for

Dingodinium minutum,

which is a common species t h r o u g h o u t the Volgian. The assemblages are comparable to those recorded in the Danish subbasin a n d the S k a g e r r a k - K a t t e g a t platform area, the Central Trough, and England. The as- semblages are similar to those described from the Subboreal province of e.g. Ioannides

et al.

(1976), R a y n a u d (1978), Barron (1989), except for the ab- sence of some of t h e index species.

Klimovi Zone

The last occurrence of

S. ? inaffecta

is in the lower p a r t of this zone. In t h e southern part of the North Sea this species is recorded in the lower part of the Elegans Zone (Cox

et al.

1987), equi-

The boundary between these two zones is not clearly differentiated in the samples studied. The index species of the

G. dirnorphum

Subzone

b, Cribroperidinium? longicorne

is not recorded above the Kimmeridgian in Poland.

The last occurrence of

Oligosphaeridium patulum

in England is at the top of the Pectinatus Zone, indicating the

G. dimorphum

Zone, Subzone c. In Poland, it is found sporadically in the Lower Volgian up to and including the

Isterites

horizon, which t e r m i n a t e s the Tenuicostata Zone. Using

O. patulum

for correlation, this m a y indicates t h a t the suggested boundary between the Lower and Middle Volgian in the Polish subprovince correlates to t h a t of the Subboreal province. Subzone d and/or e are questionably recorded in the small interval of the studied section, which is only dated as s t r a t a intermediate between t h e

Is-

terites

horizon and the Scythicus Zone.

Glossodi-

nium dimorphum

constitutes about 15% of the dinoflagellate cyst assemblage. R a y n a u d (1978) recorded

G. dimorphum

as most common in the Rotunda and Albani Zones.

Occisucysta balia

is recorded up to the base of the Scythicus Zone, which m a y indicate, t h a t it is questionable if ei- t h e r one or both subzones are present.

S c y t h i c u s Zone

Scythicus Subzone

: the base of this subzone is m a r k e d by the first appearance of

Dichado-

gonyaulax culmula

a n d the last occurrence of

Oc-

cisucysta balia,

which indicates t h e b o u n d a r y be- tween the

G. dimorphum

Zone and t h e overlying

Dichadogonyaulax culmula

Zone.

Scriniodinium

inritibilum

occurs to near the top, but, not at the actual top of the Scythicus Subzone, which allows a correlation of the major part of the Scythicus Subzone to the

D. culmula

Zone, Subzone a (see also below).

Dichadogonyaulax pannea

occurs to

t h e t o p o f t h e S c y t h i c u s S u b z o n e d a t i n g t h e top as no y o u n g e r t h a n t h e Dingodinium spinosum

Zone.

Zarajskensis Subzone : t h e u p p e r m o s t J u r a s s i c beds of t h e H o l y C r o s s M o u n t a i n s a r e a w e r e de- posited u n d e r h i g h e n e r g y , low s a l i n i t y or brack- i s h l a g o o n a l c o n d i t i o n s w i t h Pinnae bivalves. T h e s e b e d s y i e l d e d a n a s s e m b l a g e o f a n e w Fro- mea sp. (56%), Pterospermella sp. (39%), L e i o s p h e r e s , Pareodinia halosa, Sentusidinium

spp. a n d Tasmanites. The b i o s t r a t i g r a p h i c posi- tion of t h e Z a r a j s k e n s i s S u b z o n e c a n n o t be estab- lished f r o m this a s s e m b l a g e a n d t h e u p p e r b o u n d a r y of t h e S c y t h i c u s Zone c a n n o t be correla- t e d to t h e S u b b o r e a l province u s i n g d i n o f l a g e l l a t e cysts.

C O N C L U S I O N S

T h e i n v e s t i g a t i o n of L a t e J u r a s s i c d i n o i l a g e l l a t e cysts f r o m a m m o n i t e - d a t e d s a m p l e s f r o m P o l a n d h a s p r o v e d it possible to u s e m a n y of t h e dinofla- gellate c y s t z o n e s a n d s u b z o n e s of t h e D a n i s h - E n g l i s h a r e a in P o l a n d , a n d t h a t t h e z o n a t i o n ap- p e a r s to be i s o c h r o n o u s . K i m m e r i d g i a n d i n o f l a g e l l a t e cysts f r o m t h e mid- dle D i v i s u m Zone i n d i c a t e s a c o r r e l a t i o n to t h e m i d d l e M u t a b i l i s Zone of E n g l a n d . I t is s u g g e s t e d t h a t t h e m i d d l e D i v i s u m Zone of P o l a n d correla- t e s to t h e m i d d l e M u t a b i l i s Zone of E n g l a n d , in- d i c a t i n g a d i a c h r o n o u s b a s e of t h e M u t a b i l i s Zone f r o m t h e B o r e a l s u b p r o v i n c e to t h e S u b m e d i t e r r a - n e a n province. V o l g i a n d i n o f l a g e l l a t e c y s t s in t h e S c y t h i c u s Zone of P o l a n d allows a reliable c o r r e l a t i o n of this zone w i t h t h e A l b a n i Zone of D e n m a r k a n d E n - gland.

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