Provenance and diagenesis of siliciclastic and organic material in the Albian-Turonian sediments (Silesian Nappe, Lanckorona, Outer Carpathians, Poland): preliminary studies

Abstract

The provenance and diagenesis of the siliciclastic and hemipelagic sediments of three lithostratigraphic units: Lhoty Formation, Barnasiówka Radiolarian Shale Formation (BRSF) and Variegated Shales from Lancko- rona area, Polish Outer Carpathians, was approached by means of petrological and geochemical analysis of the representative samples. Data show that studied succession was mainly derived from two sources: 1. a dominant terrigenous fine-grained components have affinity with average upper continental crust (basing on mineral detritus, K2O/Rb ratio and Y/Ni vs. Cr/V ratios) and 2. biogenic siliceous material and macerals. Composition varies up section and accounts for changes in the detrital supply due to eustatic sea-level changes. Organic petrology shows presence of organic detritus within the Lhoty Fm and dominance of marine-derived macerals in the BRSF. Chemical and petrological features imply a progressive deepening of the basin. The studied succession was diagenetically altered (e.g. coalification of bituminite, illitisation of smectite and pyritisation).