Late Cretaceous foraminiferids from sections in the Zabratówka area (Skole Nappe, Outer Carpathians, Poland)

Abstract

Well preserved Late Cretaceous–Palaeogene planktonic and benthic foraminiferal assemblages were studied in the Zabratowka section of the Ropianka Formation in the Skole Nappe. The Racemiguembelina fructicosa and Abathomphalus mayaroensis standard foraminiferal biozones were distinguished. The K-T boundary was recognized within the interval between samples ZB10B–ZB9A, mainly composed of marly mudstones, interlayered with thin-bedded sandstones, and is characterized by the disappearance of planktonic taxa and an abundance of agglutinated species. Foraminiferal assemblages, collected from the turbiditic flysch-type sediments, indicate a primary depositional environment on the outer shelf to the upper part of the continental slope, with shallowing during the Maastrichtian in the part of the Skole Basin studied. The foraminiferids correspond to the assemblages of a palaeobiogeographical “transition” zone, located between the Boreal and Tethyan domains.