Mapy paleotektoniczne czerwonego spągowca w Polsce

Abstract

Omówiono rozwój litofacjalny i dokonano analizy miąższościowej dolnego i górnego czerwonego spągowca.

Na tych podstawach wyróżniono regionalne jednostki paleostrukturalne oraz cały szereg jednostek lokalnych. Wydzielono molasy śródgórskie i przedgórskie. Utwory czerwonego spągowca zaliczono do asocjacji subaeralno-wulkanicznej, limniczno-fluwialnej i skał czerwonych.

PALAEOTECTONIC MAPS OF THE ROTLIEGENDES IN POLAND

Based on the lithological analysis of volcanic rocks (Fig. 2) and on the thickness analysis of sedimentary formations and complexes assignet to the Lower Rotliegendes the palaeotectonic map (Fig. 3) has been elaborated. For the estimation of subsidence a magnitude of downwarping of investigated area until the end of large scale denudation processes - i.e. until the beginning of Copper-Bearing Shale sedimentation has been assumed. Regional palaeostructural units were distinguished and their tectonic regionalization was presented (Fig. 4). They are as follows: the Mid-Sudetic Depression and the Laskowice Graben - limnic-fluvial association with volcanites, the Łużyce and Silesian Furrows – andesite - dacite sub-association, and on a Foreland the Variscan orogen - the Pomerania Furrow - rhyolite and tufaceous-ashy sub-association.

Lithofacies and thickness analysis (Fig. 6) were made to elaborate the map of Upper Rotliegendes (Fig. 5). The Upper Rotliegendes rocks belong among Red Beds association. Three sub-associations were distinguished: red, continental, coarse-clastic molasse sub-association, red continental fine-clastic molasse sub-association and sub-association of red continental beds of a stable platform. Molasse of coarse-clastic sub-association (Fig. 7) developed within depressions and intramontane troughs of the Variscan orogen. The Mid-Polish Furrow is the largest and most subsidence unit within the Variscan foreland. The furrow is filled in with molasse of the fine-clastic sub-association.