Cykliczność sedymentacji utworów ewaporatowych badenu zapadliska przedkarpackiego

Abstract

CYCLICITY OF SEDIMENTATION OF THE BADENIAN EVAPORATE DEPOSITS IN THE CARPATHIAN FOREDEEP (SOUTHERN POLAND) Summary Cyclic sedimentation is characteristic of many ancient evaporite formations (Tab. I). Correlation of selected evaporit sections of the northern and southern parts of the Carpathian Foredeep (Fig. I) allows for a distinction of five cycles (Figs. 2 - 4). The successive stages of cyclic sedimentation, expressed by the repetitive lithofacies sequence, record intensity and relation between the processes of chemical precipitation, physical accretion and biogenic productivity. The regressive nature of sedimentary cycles is marked in an alternation of relatively deep- and shallow- water complexes. Sequential analysis of evaporate sections shows a similar trend in the water depth changes and facies evolution (Fig. 5). The main internal factors controlling paleoenvironmental conditions of the cyclic evaporate sedimentation were: subsidence, tectonic and/or eustatic activity, evaporitic drawdown and sedimentary increment - all influencing the short -term evolution of the basin. During the sedimentation of evaporites, the basin axis was displaced east- and northward based on the correlation of facies sequences and the thickness of successive cyclothems Ill, IV, V (Tab. II).