Calcareous nannofossils and foraminifera from the youngest deposits of the Siary Subunit (Oligocene, Magura Nappe, Polish Outer Carpathians)

Abstract

The calcareous nannoplankton and foraminifera from the Gładyszów Beds, regarded as the youngest deposits in the northern marginal Siary Subunit of the Magura Nappe in Poland, are characterized. The material investigated comes from outcrops in the vicinity of Gładyszów and from the Gładyszów PIG-1 borehole. The analysis allowed the establishment of the age of these deposits as not older than late Rupelian–early Chattian (the calcareous nannoplankton NP24 Zone). The taxonomic affiliations, environmental associations and preservation of the microfossils were analyzed to document the sedimentary processes and environmental conditions during the geotectonic transformation of the Magura Basin in the Oligocene. These microfossils also were compared with those reported from the terminal deposits of the Outer Carpathians and the Podhale Basin.