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The Inoceramus Beds from the quarry in Szymbark, near Gorlice. 'Y Maria Dylqianka Printed in: Roanik Polskiego Towarzystwa Ceologicznego, vol. 1 (for the years 1921 and 1922), pp. 36-81. Krak6w, 1923. The age of the Inoceramus beds (formally logical investigations could better resolve this known as Ropianka beds) is one of the most problem. convoluted problems in Carpathian stratigra- Based on observations of the Cenomanian phy. Beginning in the seventies, depending on Inoceramus beds in Muntigl, where large Znoce- ongoing exploration, the age definition of ramus with thin tests occur in soft marly these beds had undergone many revisions shales, Prof Szajnocha (1898) concluded: mainly because of the controversial relation of "there are indeed among the flysch deposits the Inoceramus beds to the Paleogene. They real Znoceramus layers and these layers must were assigned consecutively to the Eocene, to belong to the Cretaceous if we want to exclu- the Neocomian, and to the Late Cretaceous. sively restrict the presence of these rather This problem has not been resolved to this different Znoceramus in this period". There- day. The Late Cretaceous age used by Walter fore, Szajnocha as well as Grzybowski be- and Dunikowski in eighties is commonly lieved that the presence of the Znoceramus in accepted. Uhlig, following the work of Paul, the Carpathian flysch can be either Thietze, and Vacek, first assumed an Early autochthonous or redeposited. It would only be Cretaceous age, but finally accepted a Late necessary to distinguish the horizons with Cretaceous age as determined by Polish Geol- autochthonous Znoceramus from those with ogists, with the assumption that the relation- redeposited ones. The fauna from Leszczyny of ship of the Inoceramus beds to Eocene is not yet WiSniowski (19071, comprised mainly of resolved. Aside from difficulties resulting Senonian ammonites such as Pachydiscus neu- from assigning these beds to the Tertiary bergicus and Scaphites constrictus, helped (according to most Polish Geologists they form resolve many of the uncertainties connected an inseparable complex of beds [with the with the age of the Inoceramus beds in the Cretaceous]), there is the problem of the pres- Carpathians. However, WiSniowski also rec- ence of smaller and larger Znoceramus frag- ognized the Lower Paleogene in these beds. He ments in the Inoceramus beds. This gives sup- disproved the theory of redeposited Inocera- port to the theory of secondary redeposition. mus in his study area by pointing out that Prof. Grzybowski, conditionally accepting complete shells of Inoceramus salisburgensis this theory, was inclined to date the Inocera- occur in the deposits in the vicinity of mus beds from the Gorlice region as Eocene Dobromil and PrzemySl. However, the age of based on microfauna that shows similarity the Inoceramus beds in the middle and western with the Eocene oil-bearing beds in the vicin- Carpathian remains an open question. ity of Krosno, so long as future micropaleonto- Maria Dylqianka During holiday trips initiated by Dr W. mica. In the lower layers, the sandstones are Kutniar, I was able to find numerous larger thickly-bedded and in the upper part thinly and smaller fragments of Inoceramus shells in bedded. In addition, layers four, five and six the quarry in Szymbark. This inspired me to of the shales contain thin sandstone interbeds. also collect a few samples of the shales that Some of these interbeds contain plant detritus. occur interbedded between sandstones where The colour of the shales is as follows: the the lnoceramus where found, and study the shales of the first two layers are relatively microfauna of these beds. In this study I pre- thinner than the others and are dark gray; sent the current state of my analysis of this shales of the third layer are brownish-gray, microfauna. Before I begin, I wish to thank transitional, and the shales of layers four, the Director of the Geological Department, five and six are yellowish-brown. The dark Prof. Szajnocha, for his help and encourage- gray shales have a white coating. ment. I will keep in deep memory the genuine Sandstones interbedded with the dark interest and much advice given by the late gray shales are also dark gray with a white Prof. Grzybowski throughout the course of this coating. Sandstones interbedded with the yel- study. Dr. Premik is acknowledged for making lowish-brown shales have the same colour the drawings of the foraminifera. and no coating. The lower sandstones are more marly, rather hard, and resistant to weather- Geologic setting and lithology of the quany in ing. The upper sandstones belonging to the Szymbark. shaly type are weakly lithified. In some of these parts, the sandstones break into a thin The quarry in Szymbark is situated a half a sheets parallel to bcdding. Among shales as kilometre from the Gryb6w-Gorlice road on well as sandstones, there are parts covered the left side of the Bielanski stream, next to with fucoids. Finally, shales and sandstone the place where the road coming from react in HC1, although not always clearly, Bielanki village crosses the stream from the and the sandy-marly shales from the upper left to the right bank for the first time, a good layers remain inactive? distance below the 340 m elevation marker. In The layers at the base of the section, simi- this 16 m high quarry, the Inoceramus beds are lar to the ones from the quarry, contain a gray exposed as sandstones and shales interbedded sandstones interbedded with gray shales with in six layers'. Their dip is southeast 2S0 - 3S0 a uniform petrographical character. The (20-21 hours). In the stream the layers from shales that dominate in these deposits are the quarry are exposed, as well as older beds more clayey then the ones from the quarry and lying at the base of the section with the same at places they grade into clays. Sandstones dip, and together with the quarry section are hard, and covered with a few small they comprise a single unit. hieroglyphs. Neither shales nor sandstones The shales are interbedded with hiero- contain any fossils except for a few glyphic sandstones (hieroglyphs on the lower foraminiferas. Despite very careful analysis side) of the shelly type, fine-grained, with of this material I did not find not even minute large quantities of mica, repeating six times. fragments of lnoceramus shells, whereas in The alterations of shales and sandstones here the quarry they are common. The Inoceramus are quite distinct. The shales are marly, espe- cially in the lower layers, the upper layers [at this point, Dylazanka devotes two pages to become more sandy. These also contain some describing the composition of aulhogenic mineral graim dispersed within the claystones. Because this I cannot find any reference to this quarry in the description has no bearing on the paleontological literature. Szajnocha, in his explanations to his part to follow, it was ornilled from this tramlation.] geological atlas, mentions the Inoceramus beds in In these sandstones, I found a well-preserved the Bielanski stream, which is above this quarry. specimen of Spirophyton, 15 cm in diameter. Szymbark 199 beds extend a few hundred meters upstream 0.9 mm. In respect to the thickness of the from the quarry, but this is not the case in the shell, this specimen resembles Znoceramus downstream direction. Here, a few paces from cripsi Mant. reported by Friedberg from the the quarry on the left bank of the stream, next Inoceramus beds in the vicinity of Rzesz6w. to the small bridge, red shales are visible The size of a specimen from Kwiaton which lying almost horizontally. Farther down- Prof. Szajnocha calls "huge" agrees more or stream on the right bank, the same red shales less with the specimen from Szymbark. Addi- are exposed intercalated with green, hard, tionally, in the same yellowish brown sand- compacted sandstones with numerous minute stones I found a fragment of the shell of this hieroglyphs on their upper surfaces. The Inoceramus of a significant thickness with sandstones and red shales exposed in the preserved ornamentation in the form of paral- stream lie almost horizontally. lel thicker and thinner costae similar to Znoce- The tectonics in this particular area is not ramus salisburgensis from the Inoceramus beds clear to me. By the stream below the quarry in Muntigl, which are presently dated as (downstream) for a distance of 150 m, as well Upper Senonian (Pachydiscus neuergicus). as on the hillside where the quarry is located, The thickness of the fragment from Szym- the Inoceramus beds are exposed. Next to the bark is 4 mm, therefore one of the largest side road leading to the main road the beds known. The size of the fragment is not impor- (dip unknown) have a different appearance. It tant because the thickness as well as its width looks as if the Inoceramus beds were thrusted is 4 an. Judging from the size of the shell the over the younger red, Eocene shales. The lay- specimens must belong to the large ones. ers from the quarry would belong to the over- Numerous, smaller fragments have shells 0.5 - thrusted part. Only studies of the larger area 3.0 mm thick. The Znoceramus from Muntigl will solve this problem. near Salzburg reach a significant size up to 20 an diameter and have thin shell up to 3 mm. Inoceramus in the Szymbark layers. They occur in the marly shales which excludes the hypothesis of their redeposition "In the deposits rich in fossils the resence of which Prof. Szajnocha (1898) strongly onor more new form. has no siJcant rnean- ing, description and labeling of incom lete spec- emphasizes. imens could even be destructive. lfut in the How can the hypothesis of redeposited rocks so poor in fossils as the Inoceramus beds Znoceramus in the Inoceramus beds from of the Ca athians, each of the recopwed spec- imens caxave double meaning pa eontolo 'cal Gorlice (Grzybowski, 1901) be applied to the and stratigraphical."(Friedberg 1907, p.

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