O stratygrafii i rozwoju kajpru w Polsce

Abstract

ON STRATIGRAPHY AND DEVELOPMENT OF THE KEUPER IN POLANDThe stratigraphy of the Keuper sediments in Poland has chiefly been based on its lithological variableness and on sedimentological premises. The Keuper in Poland is connected with stratigraphical schemes of the German Keuper. In the succession adopted in this paper the Keuper has been divided into:2. Upper Keuper c) upper gypsum series,b) reed sandstone (Schilfsandstein),a) lower gypsum series.1. Lower Keuper - Lettenkohle beds.The upper Keuper boundary, established on the basis of sedimentological considerations, extends at the top of the Upper gypsum series; overlying· this series are genetically dissimilar argillaceous sediments, frequently of conglomeratic type, which here already - represent the Rhaetic.Within the Keuper we note two great sedimentation cycles extending from a humid moderate climate towards a climate of increasing aridity and desert character. The former comprises the series of Lettenkohle and the lower gypsum beds, the latter the reed sandstone series and the upper gypsum beds.The greatest thicknesses of all Keuper horizons are connected with the western and central part of the Keuper sedimentation basin; on Polish territory the axis of this basin runs in a NW-SE direction. This direction does not conform with the axis of the sedimentation basin of the Muschelkalk, and this probably is connected with the transgressive position of the Keuper upon the Bunter sandstone, ascertained at Pasłęk.The present-day extend of the Keuper fails to tally with its sedimentary range-especially with regard to the Upper Keuper sediments. Certain changes in its primary range must have been caused by Pre-Rhaetic denudation.