Budowa geologiczna jednostki śląskiej między Bilskiem a Toboszową

Abstract

GEOLOGICAL STRUCTURE OF THE SILESIAN UNIT BETWEEN BILSKO AND TABASZOWA

The investigated portion of the flank of the Rożnów anticline reveals a complicated structure. Two parts may be distinguished there, the northeastern and the southwestern, which differ in their structures and tectonic directions. Furthermore, the southwestern part is loosened and overthrusted on the northeastern part. Dislocations running along the Dunajec and the Łososina valleys separate this element from the neighboring area.

The lower and the upper Istebna beds are the oldest member exposed here. They contain exotics of effusive rocks (porphyries, dacite-andesites, felsites and greenstones), metamorphic rooks (granitogneisses, alaskites, psephitic and psammitic gneisses, garnetiferous shales, porphyroisdal gneisses and marbles) and sedimentary: rocks (planctonic, bryozoan-foraminiferal, lithotamnian and radiolarian limestones, as well as limestones with ammonites and flits). In these beds radial imprints of medusa-like forms resembling genus Kirklandia C a s t e r  have been discovered. In some parts of these beds, numerous are bioglyphs of Paleobulia, Ceratophycus and Spirophyton types, and star-like feeding traces of annelids.

Due to the tectonic disturbances the Ciężkowice sands tones had suffered a partial reduction, hence, only their lower part survived. Only higher up, the Globigerina marls occur, interstratified in their upper part by thick bedded sandstones resembling those from the Krosno beds. Subsequently, the menilite shales are present, covered by the Krosno sandstones.