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 E 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
L . S. P I S H V A N O V A *
STR ATIGR APHICAL AND FACIAL DISTRIBUTION OF FORAMINIFERA IN MIOCENE DEPOSITS OF THE
WESTERN PART OF UKRAINIAN SSR
JI. С. ПИШВАНОВА
Стратиграфическое и фацнальное распределение фораминифер в миоценовых отложениях западных областей УССР
A b s t r a c t . I n t h i s p a p e r , t h e a u t h o r p r e s e n t s t h e d e t a i l e d s t r a t i g r a p h y o f t h e F o r e - C a r p a t h i a n M io c e n e d e p o s it s a n d c o m p a r e s t h e m w i ' t h a n a lo g o u s s e d im e n t s
of t h e T r a n s - C a r p a t h i a n s a n d t h e V o l y n o - P o d o l i a n m a r g i n o f t h e R u s s ia n P l a t f o r m . O n t h e b a s is o f m i c r o p a l a e o n t o l o g i c a l d a t a s e v e r a l k e y z o n e s a r e d i s t i n g u i s h e d , a m o n g w h i c h p l a n k t o n i e F o r a m i n i f e r a z o n e s a r e o f p a r t i c u l a r i m p o r t a n c e . T h e f o l l o w i n g f o r a m i n i f e r a l z o n e s a r e d i s t i n g u i s h e d : 1) C h a t t i a n - A q u i ' t a n i a n — t h e s m a l l G l o b i g e r i n a , C h i l o g i i m b e l i n a a n d B o l i v i n a z o n e a n d t h e s ilic e o u s m i c r o f a u n a z o n e ; 2) B u r d i g a l i a n — t h e G l o b o q u a d r i n a d e h i s c e n s z o n e a n d P o r o s o n o n i o n i n - s i g n i s z o n e ; 3) H e l v e t i a n — t h e G l o b i g e r i n a b o l l i i z o n e a n d t h e Q u i n q u e l o c u l i n a d i s t o r t a z o n e ; 4) L o w e r T o r t o n i a n — t h e C a n d o r b u l i n a u n i v e r s a z o n e a n d t h e U v i g e r i n a a s p e r u l a z o n e ; 5) U p p e r T o r t o n i a n — t h e R a d i o l a r i a z o n e , t h e G l o b i g e r i n a b u l l o i d e s a n d S p i r i a l i s z o n e , t h e B o g d a n o w i c z i a p o c u t i c a z o n e , t h e C a s s i d u l i n a c r i s t a z o n e a n d t h e S t r e b l u s g a l i c i a n u s z o n e ; 6) S a m i a t i a n — t h e C i b i c i d e s b a d e n e n s i s z o n e a n d t h e Q u i n q u e l o c u l i n a r e u s s i z o n e .
P a l e o n t o l o g i c a l a n a l y s is h a s r e v e a le d s o m e v a r i a t i o n s i n t h e s a l i n i t y o f w a t e r s i n t h e M io c e n e b a s in . H y p e r s a l i n e c o n d i t i o n s s e e m t o h a v e e x i s t e d d u r i n g t h e C h a t t i a n - A q u i t a n i a n a n d t h e T o r t o n i a n i n f a c i e s o f t h e T y r a s s a a n d T e r e b l y a s u i t e s .
O n t h e o t h e r h a n d , t h e H e l v e t i a n B e r e z h a n y B e d s , T o r t o n i a n E r v i l i a B e d s a n d S a r m a t i a n D a s h a v a s u i t e w e r e d e p o s it e d i n a n e n v i r o n m e n t o f r e d u c e d s a l i n i t y .
Miocene deposits are w id ely developed w ithin the w estern part of the USSR. Their most com plete sections occur in the Fore-Carpathian depression, w here the Stratigraphie distribution of the Foram inifera per
m its distinction of w ell defined, m icrofauna key zones. These are as follow s: the sm all Globigerina, Chilogiimbelina and Bolivina zone in the Chattian-Aquitanian Beds of the Polanitsa suite and the Lower Voro- tyshcha sub-suite and the siliceous m icrofauna zone in the Upper Voro- tyshcha sub-suite; the Globoquadrina dehiscens and the Porosononion insigne zones in the Burdigalian Stebnik suite; the Globigerina bollii and the Quinqueloculina distorta zones in the H elvetian B alich Beds;
th e Candorbulina universa and the Uvigerina asperula zones in the Lower Tortonian Bogorodchany suite; the Radiolaria, the Globigerina
* A d d r e s s : L . S . P is h v a n o v a , L v o v , p i . M i c k i e w i c z a 8. U k r . N I G R I , U S S R .
bulloides and Spirialis, the Bogdanowiczia pocutic\a, the Cassidulina cri
sta and the Streblus galicianus zones in the Upper Tortonian Kossov suite; the Cibicides badenensis and the Quinqueloculina reussi zones in the Lower Sarmatian Dashava suite (V. S. Burov and oth. il966).
Among the distinguished zones those established on the basis of planktonic Foram inifera are of special im portance as each of them corresponds to a new sedim entary cycle in the Oligocene-M iocene marine basin, connected w ith a new transgression and reflects a sequential changes of m icrofauna w ith time.
The distinction of these zones perm itted presentation of a more d etail
ed correlation of the Miocene sequence in various parts of the Fore- -Csrpathian depression, and also a new approach to some stratigraphic problems of the Trans-Carpathians and V olyno-Podolian margin of the Russian platform . These zones are used for correlation of the sedim ents exam ined w ith the coeval deposits of the Paratethys. (Alexandrowicz S., 1961, Baldi T., 1958; Bieda F., 1851; Buday T., Cicha I., 1965; Cita M. B., 1960; Drooger C. W., 1964; Friedberg W., 1939; Luczkowska E., 1964;
Ney R., 1968; Trashliew S., 1964; Voicu Sh., 1953).
The Upper Oligocene-M iocene microfauna assem blages o f the w estern districts of the Ukr. SSR have much more in common w ith those of the western Europe than with those of the Euxino-Caspian province.
For this reason the western European schem e of stratigraphic subdivision is applied here. N evertheless, the range of the stages is considered differently, new data from regions adjacent to the typical Miocene areas in the Paratethys being taken into account.
Palaeontological analysis provided evidence of hypersaline, marine conditions for the Polanitsa and Vorotyshcha suites of C hattian-Aquita
nian age. In Burdigalian, H elvetian and Tortonian tim es, a normal sali
nity and normal tem perature and gas regim e seems to have existed in the basin on the other hand, some periods were marked by reduced salinity (the fresh water Helvetian Berezhany Beds and Tortonian Ervi- lia Beds on the V olyno-Podolian margin of the Russian Platform ) or by increased salinity (the Tyrassa suite in the Fore-Carpathians and the Tereblya suite in the Trans-Carpathians, both of which are saliferous).
In the Sarmatian sedim ents, numerous indices of brackish character of the basin are observed.
CHATTIAN — AQUITANIAN
T h e P o l a n i t s a s u i t e , up to 400 m thick, consists of grey carbonaceous sandstones, argillites and clays, w ith conglom erates at the base. The Polanitsa sedim ents overly the Oligocene M enilite suite. They are developed m ainly in the Fore-Carpathian depression and in the Skole unit of the Eastern Carpathians. In the Trans-Carpathians and on the V olyno-Podolian, the equivalents of the Polanitsa Beds are lacking.
The Polanitsa suite contains the follow ing considerably diversified Foraminifera:
Siphonodosaria aff. exilis (N e u g e b.), S. inexculta S u b b., S . stric- ticollum S u b b . , Valvulineria ignorabilis S u b b . , Gyroidina marina P i s h v., Eponides binominatus S u b b . , E. octoaameratus S u b b . , Ala- bamina typica S u b b . , Cibicides borislavensis A i s., C. sigmoidalis S u b b., Nonion postgraniferum S u b b., Florilus vitriumbonatus S u b b., Melonis praevius S u b b., Globigerina pseudoedita S u b b . , Subbotina
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22 R o c z n i k G e o l o g i c z n y t o m X X X I X
trilocularis ( d ’ O r b.), Globigerinella evoluta S u b b . , G. praemicra S u b b . , Cassigerinella globolocula L. I v a n o v a , Cata psy dr ax venzoi B o r s e t t i , Globorotalia tetracamerata S u b b., G. brevispira ( S u b b.), G. denseconnexa S u b b., Globoquadrina aff. rohri ( B o l i i), Acarinina inaequiconica S u b b., Streblus alius S u b b., Buliminella rara P i s h v., Baggatella divulgata S u b b . , B. altiuscula S u b b., Caucasina tenebri
cosa P i s h v., Uvigerinella hybridica S u b b . , Cassidulina convexilo- cula S u b b . , Bolivina dentelata S u b b . , B. spathulata W i l l i a m s o n , B. subdilatata P i s h v., B. hebis M a c f a d y e n , B. angusta P i s h v., B. cognata S u b b . , B. aenariensiformis M i a t l u k , Bolivinita cuneo
lus S u b b . , Chilogiimbelina gracillima ( A n d r e a e ) , Ch. plana L. I v a n o v a , Ch. pseudostriata L. I v a n o v a .
In addition to Foram inifera, siliceous sponges of the Lithistida group occur. Molluscs are not found, except for the rare Spirialis in the low er
most part of the suite.
The foram iniferal assem blage of the Polanitsa suite is characterized by an abundance of species and by numerous specim ens of very sm all dimensions. Planktonie species are m ost characteristic and frequent.
Both the m icrofaunal assem blage and the lithological features of the Polanitsa suite are very sim ilar to those of the overlying Lower Voro-
tyshcha sub-suite.
T h e V o r o t y s h c h a s u i t e is also developed in the Fore-Car
pathians and in the Skole unit in the eastern Carpathians. In the Trans- -Carpathians, the saliferous Negrov su ite seem s to correspond to it. The Vorotyshcha suite is subdivided into the Lower and Upper Vorotyshcha sub-suites.
The Lower Vorotyshcha sub-suite, which is locally replaced by the Polanitsa suite, consists of grey, gypsum -bearing clays and of sand
stones. The thickness of the sub-suite amounts to 300 m. M olluscs have not been found in it. The foram iniferal assem blage consists of the follow ing forms:
Ammodiscus tenuiculus S u b b., Spiroplectammina angustilocula S u b b . , Nodosaria sp., Frondicularia sp., Gyroidina marina P i s h v . , Eponides binominatus S u b b . , E. alabaminaeformis S u b b . , Alaba- mina typica S u b b . , Asterigerina planorbis ( d ’ O r b.), A. falcilocularis S u b b . , Cibicides borislavensis A i s., C. sigmoidalis S u b b . , Nonion post graniferum S u m m., Florilus aff. boueanus (d’O r b.), Melonis pr ae
vius S u b b., Globigerina pseudoedita S u b b., Subbotina trilocularis ( d ’ O r b.), Globigerinella evoluta S u b b . , G. praemicra S u b b . , Cas
sigerinella globolocula L. I v a n o v a , Globorotalia tetracamerata S u b b., G. brevispira ( S u b b .), G. hexacamerata S u b b., ’ G. denseconnexa S u b b . , Globoquadrina aff. rohri ( B o l l i), Acarinina irtiaequiconica S u b b . , Streblus alius S u b b., Buliminella rara P i s h v . , B. elegan- tissima ( d ’ O r b.), Baggatella divulgata S u b b., B. altiuscula S u b b . , Reussella regularis S u b b., Caucasina tenebricosa P i s h v . , Uvigerinella hybridica S u b b., Cassidulina globosa H a n t k e n, Cassidulina subglo- bosa B r a d y , Bolivina subdilatata P i s h v . , B. aff. arta M a c f a d y e n , B. aenariensi for mis M i a 1 1 u k, B. angusta P i s h v . , B. scalprata ( S c h w a g e r ) , Bolivina cuneolus S u b b., Chilogiimbelina gracillima ( A n d r e a e), Ch. plana L. I v a n o v a , Gumbelitria sp. M oreover spong
es of the Lithistida group are present.
Close sim ilarity betw een the Polanitsa and Lower Vorotyshcha Fora
m inifera assem blages perm itted the distinction of a common foram ini-
— 330' —
feral zone of sm all Bolivina, Globigerina and Chilogiimbelina (S u b b o- t i n a 1960). This common foraminiferal assem blage is as follows: Epo- nides octocameratus S u b b . , Alabamina typica S u b b . , Cibicides bo- rislavensis A i s., Globigerina pseudoedita S u b b . , Subbotina trilocu- laris ( d ’ Or b. ) , Globoquadrina aff. rohri ( B o l l i ) , Globigerinella e v o J luta S u b b . , G. praemicra S u b b . , Cassigerinella globolocula I v a n o v a , Globorotalia brevispira ( S u b b.), Bnggatella altiuscula S u b b . , Caucasina tenebricosa P i s h v . , Trifarina sp., Bolivina aenariensiformis M i a 1 1., B. subdilatata P i s h . , Chilogiimbelina cubensis (P a 1 m.),
Ch. gracillima A n d r e a e.
A striking developm ent of this fauna is observed w ithin Polanitsa and the first half of Lower Vorotyshcha time, w hile its gradual disap
pearance begins in the second half of Lower Vorotyshcha time and in Upper Vorotyshcha time. This extinction seem s to be associated with increasing salinity of the basin, preceding a new sedim entation cyci \
The Polanitsa suite and the Lower Vorotyshcha subsuite contain an oligohaline microfauna assemblage, which is characterized by sm all tests and by the abundance of Globigerina, Chilogiimbelina, Bolivina and Cibicides w ith a fine w all. The occurrence of num erous specim ens of Chilogiimbelina cubensis P a l m e r , Ch. gracillima A n d r e a er Cassigerinella globolocula L. I v a n o v a indicates the Oligocene age of these beds ( V i a l o v , P i s h v a n o v a 1959).
The Upper Vorotyshcha sub-suite, like the Lower Vorotyshcha one, is represented by grey brecciated clays, w ith intercalations of light grey sandstones. In contrast w ith the Lower Vorotyshcha sub-suite, it is w ith out carbonate rocks and contains intercalations of conglom erates (Za
gorsk conglom erates) and lenses of potassium and sodium salts. The brecciated, saliferous clays of this sub-suite contain numerous fragm ents of siliceous sponge spicules and Radiolaria, arenaceous Foram inifera and rare small, calcareous Foraminifera of the Polanitsa-V orotyshcha type.
A m icrofaunal assem blage of this type allow s the siliceous microfauna zone ( S u b b o t i n a , 1960) to be distinguished w ithin the Upper Voro
tyshcha sub-suite.
In some sections, it is im possible to distinguish the Upper V orotysh
cha sub-suite from the Lower Vorotyshcha one. Thus, for both those sub- -suites, as w ell as for the Polanitsa su ite the same age (C hattian-A qui- tanian) is accepted. The thickness of the Upper Vorotyshcha sub-suite is more than 1000 m.
The m icrofaunal assem blage of the Upper Vorotyshcha sub-suite consists of the follow ing forms:
Rhabdammina exilis M i a 1 1 u k, Proteonina bucculenta S u b b.r Glomospira charoides ( P a r k e r et J o n e s ) , G. gordialis ( P a r k e r et J o n e s ) , G. pileolus S u b b . , Ammodiscus aequispiralis S u b b . , Spiroplectammina aff. spectabilis ( G r z y b . ) , Arenobulim ina tertiaria S u b b . , Nodosaria sp., Lagena cf. striata d ’ Or b . , Dentalina sp., Cri- stellaria sp., Eponides binominatus S u b b . , E. umbonatus (R e u s s), E. octocameratus S u b b., Asterigerina aff. planorbis d’O r b., Cibici
des borislavensis A i s., C. sigmoidalis S u b b . , C. p y g m e u s (H a n t k e n), Florilus ex gr. boueanus ( d ’ O r b.), Globigerina pseudoedita S u b b.„
Globigerinella praemicra S u b b . , G. evoluta S u b b . , Globorotalia hexa- camerata S u b b . , G. brevispira ( S u b b . ) , G. denseconnexa S u b b . , Globoquadrina sp., Streblus sp., Elphidium sp., Hopkinsina sp., Cassidu- lina margareta K a r r e r., C. punctata R e u s s, Bolivina subdilatata
22*
P i s h . , B. fastigia C u s h . , Chilogiimbelina aff. globifera ( R e u s s), Ch. pseudostriata L. I v a n o v a , Ch. plana L. I v a n o v a . Moreover, numerous Radiolaria occur: Cenosphaera semisphaerica S u b b., Xipho- stylus sp., Spongiomma sp., Cenellipsis aff. elliptica L i p m a n, Cyrto- calpis saccula S u b b . , Dictyocephalus sp., Dicolocapsa pupoides S u b b.,
D. bicamerata S u b b . , D. piriformis S u b b . , D ic tyom itra cellulata S u b b . , D. ex gr. striata L i p m a n, Lithomitra turriformis S u b b .
The presence of the above m icrofaunal assem blage in the saliferous sedim ents of the Upper Vorotyshcha sub-suite may 'be explained by the supposition that the calcareous Foraminifera tests w ere dissolved in the hypersaline w aters w hile the siliceous and arenaceous ones had been w ell preserved. The sponge spicules in the Fore-Carpathian depression may be considered as a characteristic index of saliferous sediments.
BURDIGALIAN
T h e S l o b o d a suite consists of coarse conglom erates. The suite unconform ably overlies the Palaeogene flysch deposits, indicating that the folding phase preceded accum ulation of the conglom erates m entioned above.
The sandy-argillaceous D o b r o t o v s u i t e overlies the Sloboda Beds. It is linked by gradual transition w ith the underlying Sloboda and overlying Stebnik suites. The Dobrotov suite is represented by a fly - schoid alternation of sandstones, argillites, marls and grits. The occur
rence of ripple marks, distinct hieroglyphs, numerous bird traces, artio- dactyl and other animal footprints indicates the proxim ity of a shore line. In the microfauna, rare Eponides umbonatus (d ’ O r b.), Globoro
talia mayeri C u s h m a n et E l l i s . , Porosononion insignis P i s h v . , Streblus pseudobeccarii P u t r j a and Cassidulina margareta K a r r e r were found.
The Sloboda and the Dobrotov suites are easy to distinguish litho- logically from the upper Vorotyshcha sub-suite and Zagorsk conglo
merates; they are ten tatively assigned to the Burdigalian stage.
T h e S t e b n i k s u i t e consists of variegated (pink, brown, grey and greenish) clay marls, alternating w ith grey, occasionally reddish, cross-bedded sandstones. They are up to 2500 m. thick. In the area betw een the Tysm enitsa and Viar rivers (north-western Fore-Carpa
thians), a layer of exotic conglom erate, equivalent to the Dubnik conglo
merate of Poland, occurs at the base of this suite. In the Nadvorna region (south-eastern Fore-Carpathians), sandstones and clays of this suite contain desiccation cracks, ripple marks, and the foot im prints of birds.
In the upper part of the Stebnik suite w ithin the Bogorodchany region, a horizon of Sadzava sandstones occurs. Elsewhere (Kalush, Drohobych, Utoropy) the saliferous series is developed at the top of this suite. It should be noted here, that some geologists place this saliferous series in the middle of the Stebnik suite as the Kalush Beds or assign it to the Upper Vorotyshcha sub-suite ( S u b b o t i n a 1960). In some sections, the upper part of the Stebnik suite contains some grey tu ff intercalations, 10— 30 im. thick.
Num erous, typically Miocene Foraminifera appear in the variegated clay marls and sandstones of the Stebnik Beds. Molluscs are not found in them. The microfauna assem blage consists of the follow ing forms:
— 341 —
Rhabdammina sp., Hyperammina sp., Glomospira charoides ( P a r k e r et J o n e s ) , Spiroplectammina minuscula P i s h v . , Pyrgo affinis ( d ’ O r b.), Lagena vulgaris d ’ Or b . , Cristellaria ex gr. initiata (d ’ O r b.), Siphonodosaria elegantissima M i a 1 1 u k, Glandulina laevigata d ’ O r b., Asterigerina aff. planorbis ( d ’ O r b.), Gyroidina marina P i s h v . , G. sol- danii d ’ Or b . , Eponides umbonatus ( R e u s s), E. nanus ( R e u s s), E. octo
cameratus S u b b . , E. binominatus S u b b . , Cancris brongniarti. d’O r b., Siphonina reticulata (C z j z e k), Cibicides ungerianus (d’O r b .), Cibi
cides boueanus (d’O r b .), C. borislavensis A i s., Nonion tumidulus P i s h v . , Porosononion insigne P i s h v . , Melonis soldanii (d’O r b .), Pul- lenia bulloides ( d ’ O r b.), Florilus boueanus ( d ’ O r b.), Globigerina altispira ( C u s h , et J a r v.), G. bulloides d’O r b., G. pseudoedita S u b b . , Subbotina woodi connecta ( J e n k i n s ) , Globigerinella praemicra S u b b . , G. evoluta S u b b . , Globigerinoides trilobus ( R e u s s), Glo
boquadrina langhiana C i t a et G e l a t i , G. quadraria ( C u s h , et E 11 i s o r), G. dehiscens ( Ch a p . , P a r r et C o l 1.), G. proxima ( P i s h v.), Globorotalia hexacamerata S u b b . , G. brevispira (S u 'b b.), G.
tetracamerata S u b b., G. mayeri C u s h , et E 11 i s., G. denseconnexa S u b b . , G. eximia P i s h v . , Streblus eobeccarii P u t r j a , Elphidium macellum (F i c h. et M o 11), E. stebnicaensis P i s h . , Buliminella rara P i s h v . , Virgulina schreibersiana C z j z e k , Bulimina elongata d’O r b., Virgulina conspicua P i s h v . , Cauaasina tenebricosa P i s h v . , Uvigeri- na bononiensis F o r n . , Cassidulina punctata R e u s s , C. subglobosa B r a d y , Bolivina subdilatata P i s h v . , B. miocaenica (M a c f a d y e n), B. fastigia C u s h . , B. punctata R e u s s , B. floridana C u s h .
In some sections of the suite (at Novitsa village), Lepidocyclina and Miogypsina were found in the upper part .Moreover, in numerous sections of this suite, sponge spicules, spines of echinoderm s and charophytes
occur.
The distribution of m icrofauna w ithin the thick Stebnik series is uneven. In its lower part, some sm all Foraminifera of Vorotyshcha type and sponge spicules are present. The upper part of the Stebnik suite is characterized by a more abundant m icrofaunal assemblage; in approxi
m ately the middle part of the suite accum ulations of ostracods, charo
phytes and disc-shaped forms are observed.
The Porosononion insignis zone is developed in the upper part of the Stebnik suite (the Sadzava sandstones). In this zone, the characteristic Stebni'k Foraminifera are present, associated with the ostracod Loxo- concha dromax L i v e n t a l and rare charophytes. They are reipresent- ed by the follow ing forms: Siphonina reticulata C z j z e k , Cibicides ungerianus (d ’ O r b.), Florilus boueanus ( D ’ Or b. ) , Melonis soldanii ( d ’ Or b. ) , Porosononion insigne P i s h v . , Globigerina bulloides d ’ Or b . , Globoquadrina dehiscens ( C h a p . , P a r r et Co l l . ) , Streblus paeudobeccarii P u t r j a , Elphidium stebnicaense P i s h v . , Caucasina
tenebricosa P i s h v .
The above foram iniferal assemblage as a w hole and Lepidocyclina in particular indicate a Miocene, most probably Lower Miocene (Burdi
galian) age of the suite. The Miocene Foraminifera in the Stebnik sedi
m ents are accompanied by redeposited Cretaceous and Eocene forms.
There are: Rhabdammina lineariformis M i a 1 1 u k, Globigerinoides conglobatus B r a d y , Hantkenina alabamensis C u s h . , Globotruncana sp. and Rotalia lithotamnica U h 1 i g.
The appearance and developm ent of the planktonic form Globoqua-
drina dehiscens in the Stebnik suite perm its correlation of this suite with the Burdigalian Globojuadrina dehiscens zone in Italy ( P i s h v a n o v a
1965).
T h e B u r k a l o s u i t e in the Trans-Carpathians is referred to the Burdigalian. The m icrofaunal assemblage of this suite differs from that of the Stebnik one in the presence of numerous representatives of the Lagenidae and Bulim inidae fam ilies. The follow ing forms were found in the Burkalo deposits: Haplophragmoides aff. rotundidorsatum H a n t k . , Spiroplectammina carinata ( d ’ O r b.), Clavulina communis d ’ Or b . , Robulus cultratus ( d ’ O r b.), R. inom atus ( d ’ O r b.), Marginulina sub- bullata H a n t k . , Nodosaria pyrula d ’ Or b . , N . aff. budensis H a n t k . , N. longiscata d ’ Or b . , Dentalina pauperata d ’ Or b., Quinqueloculina aff. carinata d ’ Or b . , Bulimina inflata S e g., Florilus boueanus ( d ’ O r b.), Globigerina sp. This assemblage is very sim ilar to that of the Lower Tortonian Korytnica clays in Poland. It is supposed that the Burkalo suite, being an equivalent o f the Korytnica clays, should be assigned to Lower Tortonian.
H E L V E T I A N
T h e B a l i c h s u i t e differs from the Stebnik one in grey and green colouration of rocks, m ostly coarse-grained sandstones, conglo
merates and tuffs. It is up to il600 m. thick. The Balich suite is developed in the Fore-Carpathian trough. It is coeval w ith the Tereshul conglo
merates in the Trans-Carpathians and w ith the N agoryany (Oncophorian) and Berezhany fresh-w ater beds of the Volyno-Podolian margin of the Russian platform.
The Balich microfaunal assemblage includes numerous species, com
mon to the Stebnik suite. These are Cibicides ungerianus ( d ’ O r b).
Nonion tumidulus P i s h v . , Melonis soldanii ( d ’ Or b. ) , Globigerinoi- des trilobus ( R e u s s), Subbotina woodi connecta (J e n k i n s), Globo- rotalia brevispira ( S u b b . ) , Globoquadrina dehiscens ( C h a p . , P a r r et Co l l . ) , Streblus pseudobeccarii P u t r j a, Elphidium stebnicaensis P i s h v . , Bolivina miocaenica M a c f . Numerous, redeposited Creta
ceous Foraminifera and Radiolaria are also present. The forms m entioned above, are accompanied by abundant Globigerina bollii C i t a et G e - 1 a t i, occurring in the low er part o f the Balich suite, and Quinque
loculina distorta P i s h v . , Q. mayerina d ’ Or b . , Q. ovula K a r r e r , Gastropoda and Ostracoda in its upper part. These assem blages are dis
tinguished! as the Globigerina bollii and the Quinqueloculina distorta .•zones.
The Globigerina bollii zone, besides numerous specim ens of the zonal .index form »contains such species as Globigerinoides bisphaerica T o d d ,
•Globorotalia scitula B r a d y , G. mayeri C u s h , et E l l i s . , Cibicides .ungerianus ( d ’ O r b.), Cassidulina crassa d ’ O r b . This zone w as first established in beds of the m iddle part of the Langhiano in Italy, w hich resem bles the low er part of the Fore-Carpathian Balich suite.
The salinity of the Fore-Carpathian basin decreased at the end of the H elvetian cycle of sedim ention. This phase is marked by the oligohaline Quinqueloculina distorta zone. E xtensive developm ent of abundant M ili- olidae and the presence of Gastropoda and Charophyta in the upper part of the Balich suite confirm the supposition about a change in the salinity of the sea water at that time.
— 31413 —
T h e N a g o r y a n y B e d s in the Trans-Carpathians consist of grey to brownish sandstones, unconform ably overlying grey lim estones of Turonian age. The N agoryany Beds are only 0,12— 0,15 m. thick. In these 'beds, a poor assem blage of Foraminifera was found corresponding to normal salinity environm ent. It consists of the follow ing forms: Trilo- culina gibba d ’ Or b . , Florilus boueanus ( d ’ O r b.), Elphidium fich- tellianum ( d ’ O r b.), Discorbis obtusus ( d ’ Or b. ) , Rosalina viennen- sis d ’ O r b., Cibicides bogdanovi S e r., Cibicides lobatulus ( W a 1 k et J a c o b ) , Globigerina bulloides d ’ Or b . , Globigerinoides trilobus ( R e u s s), Globorotalia m ayer i C u s h , et E l l i s . , Streblus eobeccarii
P u t r j a .
T h e B e r e z h a n y B e d s are represented by grey, m arly lim e
stones, 6— 8 m thick, containing abundant Charophyta, Ostracoda and Gastropoda. Scarce Florilus boueanus ( d ’ O r b.), Discorbis obtusus ( d ’ O r b.), Cibicides bogdanovi S e r., Rosalina viennensis d ’ O r b . are
found in these beds.
L O W E R T O R T O N I A N
Lower Tortonian sedim ents are represented by the Bogorodchany su ite in the Fore-Carpathians, the N ovoselitsa suite in the Trans-Carpa
thians and the Baranov, N ikolaev and Ervilia Beds, w ith in the V olyno- -Podolian margin of the Russian Platform.
W ithin the entire folded Carpathian area, the Lower Tortonian sedim ents rest unconform ably on the Burdigalian and H elvetian deposits, b u t m ainly on the Palaeogene, Cretaceous, Jurassic and Palaeozoic for
mations. They begin a new, Middle Miocene sedim entary cycle, which was accompanied by volcanism and the formation of thick key horizons of tuffs (N ovoselits — D anilov tuffs in the Fore-Carpathians, Dej tu ff in
Rumania).
The w ell known Candorbulina universa zone is associated w ith the beginning of this cycle. It w as established in the Fore-Carpathians and later Observed in the Lower Tortonian Beds of the Trans-Carpathians and Volyno-Podolian, as w ell as in Roumania, Poland, Hungary, Bulgaria, S yria, Italy, Albania, N ew Zealand and Australia.
In the w estern territory of the USSR, the Candorbulina universa zone is best developed in the Bogorodchany suite, w here it corresponds to the low er m arl-tuff member of the suite. The Uvigerina asperula zone is distinguished in the upper sandy-argillaceous m em ber of the suite.
The low er part of the suite, i.e. the Candorbulina universa zone, consists of grey-w hitish tuffs, alternating w ith grey-greenish marls and occasionally w ith argillites and sandstones. These sedim ents contain Foraminifera of the Globigerinidae fam ily in such abundance that to nam e them Globigerina marls would be appropriate. The m ost char
acteristic forms in this zone are: Candorbulina universa J e d 1., Biorbulina bilobata ( d ’ Or b. ) , Beella opinata ( P i s h v . ) , Globigerino
ides transitoria B l o w , G. bisphaerica T o o d, G. trilobus ( R e u s s), Globoquadrina altispira ( C u s h , et J a r v.), Globorotalia mayer i C u s h , et E l l i s . , G. scitula B r a d y , Spiroloculina tenuissima R e u s s , Cibicides ungerianus ( d ’ O r b.), C. ungerianus ukrainica P i s h v . , Bu- limina buchiana d ’ O r b., Pleurostomella alternans S c h w a g . , Boli
vina soalprata retiformis C u s h m . , Pseudoparella nova P i s h v .
N early all the species m entioned above are typical Lower Tortonian forms, w hich are not found in the overlying Upper Tortonian deposits, or occur there only as very rare specimens.
The Candorbulina zone is distinguished 'by the m arl-tuff com plex, characteristic planktonic Foraminifera assem blage and relatively sm all thickness (60— 100 m).
Since this zone is observed, not only in the Soviet Carpathians, but also in the Middle Miocene deposits of m any regions throughout the world, it may be called a global zone. It can be used for correlation w ith even very distant Middle Miocene deposits, containing tuffogenic rocks.
In the overlying Uvigerina asperula zone, the petrographic com
position of rooks changes considerably. Clays becom e more sandy, num er
ous intercalations o f sandstones appear. The upper part is marked by Lithothamnium lim estones. The composition and distribution of Fora
m inifera in this part of the section differs som ewhat from those in the Candorbulina universa zone. Such globigerinids as Candorbulina universa J e d l . , Globoquadrina altispira ( C u s h , et J a r v.), Biorbulina bilo- bata (d ’ O r b.), Globigerinoides transitoria B l o w , G. bisphaerica T o d d still occur, but here they are rather rare. Moreover, num erous tests of Nodosaria sp. Robulus sp., Spiroplectammina carinata ( d ’ O r b.), Clavulina communis ( d ’ Or b. ) , Bulimina inflata S e q . , Uvigerina asperula C z j z e k, Sphaeroidina bulloides d ’ O r b . and Cibicides un
gerianus ( d ’ O r b.) appear.
In t h e N o v o s e l i t s a s u i t e of the Trans-Carpathians, as in the Bogorodchany suite, two m icrofaunal zones are distinguished: the' Candorbulina universa and the Uvigerina asperula zones w ith micro
faunal assemblages analogous to those of the Fore-Carpathians (P e- t r a s h k e v i c h , P i s h v a n o v a , 1968).
On the V olyno-Podolian margin, the B a r a n o v B e d s , which consist of sands, sandstones, marls and lim estones, approxim ately 25 m.
thick, contain Pseudamussium corneum denudatum R e u s s , Cardium baranovense H i 1 b., Amu ssium comitatum F. As to the microfauna, Triloculina gibba d ’ Or b . , Lagena striata d ’ Or b . , Dentalina elegans d ’ Or b . , Cibicides lobatulus (W a 1 k et J a c o b.), C. ungerianus ( d ’ Or b. ) , Florilus boueanus ( d ’ Or b. ) , Gyroidina soldanii ( d ’ Orb. ), . Nonion umbostelligerum S e r., Globigerinoides trilobus ( R e u s s), Candorbulina universa J e d l . , Biorbulina bilobata ( d ’ Or b. ) , Globo
rotalia mayeri C u s h , et E l l i s , and Ehrenbergina podolica W o- l ö s c h , occur there.
In the N i k o l a e v B e d s , represented b y friable sandstones and marls, with abundant Bryozoa, Serpula and H eterostegina, the follow ing microfaunal assem blage was found: Globulina gibba d ’ Or b . , Discorbis squamula ( R e u s s), Globigerinoides transitoria B l o w , Amphistegina hauerina d ’ O r b., Heterostegina costata d ’ O r b., Heterostegina pnae- costata P a i p p et K ü p p e r , Uvigerina as,peruZa C z j z e k , Gypsina vesicularis ( P a r k , et J o n e s), Elphidium fichtellianum ( d ’ O r b.).
Candorbulina universa occurs only occasionally here.
Among Foraminifera of the Baranov and the N ikolaev Beds Lagenidae and Heterostegina play an im portant role in addition to Globigerina ( P i s h v a n o v a , 1963).
— 3i45|
U P P E R T O R T O N I A N
The earliest phase of Upper Tortonian sedim entation is the Tyrassa su ite in the Fore-Carpathians and the Tereblya suite in the Trans-Carpa
thians.
T h e T y r a s s a s u i t e consists of anhydrite, gypsum and halite w ith clay intercalations: it overlies either Cretaceous beds or various M iocene deposits and the thickness reaches 200— 250 m.
In the clays intercalated w ith evaporites, abundant Upper Tortonian Foram inifera w ere found: Quinqueloculina akneriana d ’ O r b., Bilo- culina clypeata d ’ O r b., Spiroloculina canaliculata d ’ O r b., Cibicides lobatulus (W a 1 k e r et J a c o b ) , Melonis soldanii (d ’ O r b.), Globi- gerina bulloides d ’ O r b., Globorotalia mayeri C u s h m. et E l l i s . , Bulimina elongata d ’ O r b., B. longa (V e n g 1.), Uvigerina semiornata d ’ O r b., Sphaeroidina austriaca d ’ O r b . This microfauna is character
istic for the younger sedim ents of the overlying Kossov suite and indi
cates a gradual passage from the saliferous, lagoonal, Tyrassa sedim ents into the polyhaline Kossov Beds.
T h e T e r e b l y a s u i t e is represented by saliferous sedim ents w ith the clayey intercalations, containing rare, badly preserved Quin
queloculina sp., Globorotalia mayeri ( C u s h , et E 11 i s.), Bulimina elongata d ’ Or b . , B. subulata ( C u s h , et J a r v.), Bolivina dilatata R e u s s.
T h e overlying K o s s o v s u i t e in the Fore-Carpathians is sub
divided into the Verbovets, Prut, Kolomya and K ovalev Beds (from bottom to top). The foram iniferal assem blage of this suite as a whole differs considerably from that of the Lower Tortonian Bogorodchany suite in having M editerranean characteristics. It is distinguished by diversification of various calcareous and arenaceous species and by the abundance of w ell preserved specimens. The arenaceous Foraminifera group w ith predominance of Bogdanowiczia pocutica P i s h v., Hyper- ammina granulosa V e n g 1., Haplophragmoid.es pinguis P i s h v . , Tex- tularia subangulata d ’ O r b . and Cyclammina pleshakovi P i s h v . , occurs abundantly only in the middle part of the Kossov suite. In the higher part of the section the arenaceous forms are represented by rare specim ens and have no stratigraphical significance. Calcareous Forami
nifera are characteristic for the w hole Kossov suite. The representatives of Buliminidae, Rotaliidae and Cassidulinidae are w ell developed. The planktonic forms are w ell represented here, but they are com pletely different from those of the Lower Tortonian sedim ents. These are: Glo- bigerina bulloides d ’ Or b . , G. globosa P i s h v . , G. paula P i s h v . , Subbotina cognata P i s h v . , Globigerinoides indigena L u c z k . The most characteristic and frequent species of the calcareous Foraminifer'a are: Valvulineria complanata ( d ’ Or b. ) , V. marmaroschensis P i s h v . , Bulimina elongata d ’ Or b . , B. ovata d ’ Or b . , B. intonsa (L i v.), B. longa (V e n g 1.), Caucasina gutsulica L i v., Uvigerina semiornata d ’ Or b . , U. perornata P i s h v . , Angulogerina angulosa (W i 11.), Cas- sidulina crista P i s h v . , Bolivina dilatata R e u s s, Sphaeroidina au
striaca d ’ Or b . , Gyroidina soldanii ( d ’ Or b. ) , Cibicides dutemplei (d ’ O r b.), C. incelebratus P i s h v . , Quinqueloculina akneriana d ’ Or b . , Biloculina clypeata d ’ O r b., Melonis soldanii (d ’ O r b.), Florilus boue- anus ( d ’ O r b.), Reussella tortonica P i s h v . , Cibicides lobatulus (W a 1 k.
et J a c o b.), Reussella spinulosa (W i 11.), Globorotalia aff. nepenthes
( T o d d ) . They are accompanied by Radiolaria, Ostracoda and spines and test fragm ents of Echinodermata. The distribution of the Foraminifera in the Kossov suite is fairly regular, perm itting the distinction of a series o f m icrofaunistic zones. These are as follow s (from bottom to top):
the Radiolaria zone, the Globigerina bulloides and Spirialis zone, the Bogdanowiczia pocutica zone, the Cassidulina crista zone and the Streblus
galicianus zone.
In the Verbovets Beds, two m icrofaunal zones, the Radiolaria zone and the Globigerina bulloides and Spirialis zone, are distinguished. These beds consist of grey clays, w ith thin intercalations of sandstones and tuffs. Tuff intercalations are developed, especially in the low er part of the beds. The presence of abundant pyrite and glauconite granules is also a characteristic feature of the Verbovets Beds. The m icrofaunal tests are often com pletely pyritised.
The first Radiolaria zone occurs at the base of the V erbovets Bsds im m ediately above the Tyrassa suite. Numerous Radiolaria such as Rho- palastrum sp., Euchitonia sp., Panartus sp., Cenosphaera sp., are confined to the ash tuffs, w hich form the key horizon in the Upper Tortonian deposits of the Fore-Carpathians.
In the Globigerina bulloides and Spirialis zone, abundant tests of the zonal markers are accompanied by numerous planktonie Foraminifera, such as Globigerina regularis d ’ O r b., G. paula P i s h v . , G. globosa P i s h v . , Subbotina cognata ( P i s h v.), Globigerinoides indigena Ł u c z k. Sim ilar m icrofaunal assem blage is also found in the Trans- -Carpathians in Roumania.
The overlying P r u t B e d s are represented by grey poorly arena
ceous clays. They contain rich assem blages of both planktonie and ben- thonic arenaceous and calcareous Foraminifera. The arenaceous Fora
minifera are: Bogdanowiczia pocutica P i s h v . , Hypera mm ina granulosa V e n g 1., Haplophragmoides undosus P i s h v . , H. pinguis P i s h v . , H. planus P i s h v . , Cyclammina pleshakovi P i s h v . Among the calca
reous Foraminifera, the fam ilies Discorbidae, Globigerinidae, Anom ali- nidae and Bulim inidae are w ell represented. The abundance of tests of arenaceous Foraminifera and of Bulimina elongata d ’ O r b . perm its the easy recognition of the Prut Beds and their separation from the sedim ents of other horizons. These beds are distinguished as Bogdano
wiczia pocutica zone. In the Trans-Carpathians, this zone is recognized in the Teresva suite. On the Volyno-Podolian margin of the Russian p lat
form, the Kleparov Beds correspond to the Bogdanowiczia pocutica zone ( P i s h v a n o v a , 1963).
The overlying K o l o m y a B e d s consist of clays, containing a little coarse-grained material. The elem ents o f typical deep w ater eury- haline fauna begin to disappear in these 'beds. The arenaceous Foram in5- fera, which occurred below, disappear almost entirely, except for Textu- laria subangulata d ’ O r b . and Cyclammina pleshakovi P i s h v . The Bulim inidae are im poverished, w hile Bulimina ovata d ’ Or b . , Cauca- sina gutsulica L i v., C. lucera P i s h v . and various Uvigerina disappear.
The representatives of the fam ilies Discorbidae and Globigerinidae are less diversified. Num erous test of Cassidulina crista in the Kolom ya Beds allow them to be distinguished as the Cassidulina crista zone. This zone may be definitely traced in the lower part of the V ulkhovets suite in the Trans-Carpathians.
The K o v a l e v B e d s are distinguished in the upper part of the
— 347 —
Kossov suite. They consist of sandstones, clays and conglom erate, w ith intercalations of carbonized plants. These beds contain a m ixed foram ini- feral assem blage, including oligohaline and polyhaline forms. These forms are: Streblus galicianus P u t r j a, Porosononion granosum ( d ’ O r b.), Nonion rotund um P i s h v . , Elphidium adven um ( C u s h m.), E. brevi- sculum P u t r j a, Discorbis imperator ( d ’ O r ’b.), Bulimina subulata (C u s h m. et P a r k.), B. intonsa L i v. When compared w ith the fauna of the underlying beds, this assem blage is characterized by an absence of thick-w alled, arenaceous tests, a sharp decrease in the number of Bulim inidae and by alm ost complete disappearance of the planktonic Foraminifera. A t the same time, a considerable enrichm ent of represent
atives of the genera Streblus, Porosononion and Elphidium is observed, indicating a significant reduction in the salinity of the basin. This reduc
tion seem s to have been caused by an increased influx of fresh water, which resulted in a change in the test structure of the fauna, their di
m ensions becoming sm aller and the w alls finer.
The V olyno-Podolian equivalent of the K ovalev Beds is the B u g 1 o v B e d s , w hich contain follow ing m icrofaunal assemblage: Quinquelc- culina akneriana d ’ O r b., Q. consobrina ( d ’ O r b.) var. nitens R e u s s, Q. longirosta d ’ O r b . Q. planicarinata (V e n g 1.), Q. seminulum L i n- n e, Nodobaculariella buglovensis V e n g 1., N. costata V e n g 1., N. po- dolica D i d k., Nummoloculina contraria ( d ’ O r b.), Spiroloculina bi- dentata D i d k., Globulina gibba d ’ O r b., Discorbis imperator ( d ’ O r b.), Conorbina miocaenica K r a s h . , Eponides haidingeri ( d ’ O r b.), Nonion rotundum P i s h v . , Rotalia magnifica K r a s h . , Streblus galicianus P u t r j a, Elphidium aculeatum ( d ’ O r b.), E. ad ven um C u s h m., E. angulatum E g g e r, E. antonium ( d ’ O r b.), E. incertum (W i 11.), Bulimina aculeata d ’ O r b . and Reussella spinulosa (R e u s s); Ostra- coda, Bryozoa and the spines of Echinodermata are also found. In the upper part of the Buglov Beds, such typical Sarmatian species as Quin
queloculina sarmatica K a r r e r, Q. reussi B o g d ., Articulina sarma- tica ( K a r r e r ) are occasionally present.
For both Kovalev and Buglov Beds the presence of abundant tests of Streblus galicianus is particularly im portant, since it forms the basis for their distinction as the Streblus galicianus zone. The sam e zone is recognized in the Beshikur suite of the Trans-Carpathians.
The above analysis of Foram inifera of the Fore-Carpathians Tortonian sedim ents and correlation of the m icrofaunal assem blages distinguished w ith the coeval West European sedim ents indicate, that Tortonian sedi
m entation displays a tw o-stage evolution, marked by tw o marine trans
gressions. The first of these took place in the Lower Tortonian, the second in the Upper Tortonian.
S A R M A T I A N
In the w estern parts of the Ukrainian SSR, Sarm atian deposits are represented by its low er division, w hile the middle part is not yet con
firmed palaeontologically. In the Fore-Carpathians the Lower Sarmatian is distinguished as the Dashava suite. In the Trans-Carpathians, the Sar- matian sedim ents are represented by the Dorobratov, Lukov and Alm ash Beds. On the Volyno-Podolian margin of the Russian platform, the Za- lesk, Listvinsk and Bessarabia Beds are developed.
