Charakterystyka mikropaleontologiczna warstw buhłowskich w ZSRR i ich odpowiedników w Polsce

Abstract

MICROP ALAEONTOLOGICAL DESCRIPTION OF BUHLOV BEDS (SOVIET UNION) AND OF THEIR EQUIVALENTS IN POLANDSummaryIn 1965 a revision was made of the molluscan fauna from a stratotype of the Buhlov Beds found to occur in the Volhynian area. Primarily, these beds were referred to Upper Tortonian, or to the so-called Pre-Sarmatian, mainly due to the presence of Sarmatian types of fauna. Later on, these were thought to belong to Sarmatian. Soviet geologists have determined the stratotype of the Buhlov Beds from Ogryzkowice, Volhynia, distinguishing 3 horizons, and restricting the notion of the Buhlov Beds only to the middle horizon G, which contains the form Venus konkensis media. Bearing the name Buhlov Beds sensu stricto, this horizon was referred by them to Tortonian, whereas the upper horizon D, lacking the form Venus konkensis media, was left on the Sarmatian. In 1967 L. Pishvanova characterized the microfaunistic content of the Buhlov Beds, coming to the conclusion that the upper part of the horizon G reveals Sarmatian microfauna representatives. In this article, the problem is presented in the light of microfauna (foraminifera) examinations. The microfauna from the individual horizons of the stratotype of the Buhlov Beds has been analysed on the basis of the works made by the Soviet authors and on the present author's elaborations. The microfauna representatives have been compared with those of the analogous beds of Poland. In Poland, the calcareous-detrital and arenaceous formations of the Roztocze region and of the area of the Świętkorzyskie Mts., as well as the so-called Syndosmya clays, which represent the horizon with Anomalinoides dividens, may be thought to be of the same age as the Buhlov Beds. The formations mentioned above reveal some microfauna assemblages that correspond to both horizons G and D, the intercalations in sands and detrital limestones disclosing mainly Sarmatian assemblages with Anomalinoides dividens. Since the succession at the microfauna may be of various nature and the age in this case is determined by the Sarmatian assemblages with Anomalinoides dividens, the horizons G and D should be thought to represent facial equivalents, and both should be referred to the Sarmatian.