Bajoska tektonika synsedymentacyjna i jej znaczenie w jurajskiej ewolucji pienińskiego basenu skałkowego

Abstract

The Jurassic crinoidal limestones in the Pieniny Klippen Belt in Poland consist of three formations (Smolegowa, Flaki and Krupianka Limestone formations), and constitute an important segment of the Middle Jurassic sequence in the Czorsztyn, Niedzica and Czertezik successions. The onset of the crinoidal sedimentation, as proved by ammonite faunas, took place during the Early Bajocian and it was preceded by a marked stratigraphical hiatus. This hiatus corresponds to the origin and uplift of the Czorsztyn Ridge. The evidences of condensation event at the beginning of crinoidal limestones sedimentation are marked by numerous sedimentological features in the lowermost part (10-20 cm in thickness) of these limestones (e.g. phosphatic concretions concentration, pyrite concretions, large clasts of green micritic limestones). Occurrence of such important correlation horizon indicates primary thickness of investigated crinoidal limestones (from ca 10 m up to 100 m), and suggests origin of synsedimentary tectonic blocks and troughs, which influenced on their original, not recently tectonically reduced, differentiation of their thickness. This Bajocian tectonic activity within Pieniny Klippen Basin corresponds very well with others Middle Jurassic Western Tethyan geodynamic reorganizations.