Rozwój transgresji aalenu i bajosu na Niżu polskim

Abstract

Since long, Bajocian deposits are known in the Polish Lowland; Aalenian deposits, on the other hand, were identified in the Lowland in 1966 (J. Kopik, 1956; J. Znosko, 1957a). Drilling activity in the southwestern part of the Polish Lowland (J. Znosko, 1958) has made possible the first analysis of the development of the Aalenian and Bajocian transgression.

On documentary maps the author has indicated outcrops and bore holes where the deposits of both the Aalenian and the Bajocian have been passed through, as well as those bore holes where the contact of deposits older than the. Aalenian with deposits younger then the Aalenian has been identified (and for the Bajocian deposits older then the Bajocian and those younger than the Bajocian).

These localities indicate, or might indicate, the margin of the spread of the Aalenian and Bajocian sea. Continuous and dashed lines indicate, in general, surface and subcenozoic outcrops of the Dogger on the author's palaeogeographical maps of the Aalenian and Bajocian of the Polish Lowland there have been entered lines of probable equal thicknesses of deposits, and in this manner has indirectly been indicated the depths of the respective basins. On these maps there also have been shown deep-seated tectonic disruptions ("tektonische Erdnahten") marked in the crystalline substratum, and the outlines of the Carpathian overthrust. Moreover, in separate maps the author has illustrated the position of identified facies of the Aalenian and Bajocian basins.