POZYCJA GEOLOGICZNA INTERGLACJALNYCH OSADÓW ORGANICZNYCH W PRUCHNEJ (KOTLINA OŚWIĘCIMSKA)

Abstract

GEOLOGICAL POSITION OF THE INTERGLACIAL ORGANIC SEDIMENTS FROM PRUCHNA (OŚWIĘCIM BASIN)

Abstract. Biogenic sediments with fragments of an interglacial succession have been found in the southern part of the Oświęcim Basin (Kończyce Plateau). This tripartite section is situated in a village of Pruchna, to the south of the Pruchna-Zebrzydowice road. The upper part of the section is of aeolian origin and contains loess-like loams with traces of palaeosoils. This sedimentary complex, exceeding 4 m in thickness, was deposited during the Middle Polish and North Polish glaciations. The middle part of the section is built of organic sediments, which represent a part of the Mazovian Interglacial succession. They rest on a thin layer of loess-like sediments. The lower portion of the section from Pruchna covers a 7-m thick series of glacigenic sediments. Deposits from the bottom of the section are of Miocene age. The section is situated in the area where two Scandinavian ice-sheet transgressions, i.e. the South Polish and Middle Polish glaciations, are supposed to have occurred. The results of our studies rule out the possibility of the presence of Middle Polish Glaciations ice-sheet in the southern part of the Oświęcim Basin. Taking into consideration the pollen succession from the Kończyce section, it may be expected that organic sediments of various interglacial ages (from the South Polish Complex or the Cromerian Complex up to the Eemian) may occur between the loess-like and glacigenic sediments related to the maximum extent of the Scandinavian ice-sheet.