Biostratygrafia osadów miocenu z otworów wiertniczych Busko (Młyny) PIG-1 i Kazimierza Wielka (Donosy) PIG-1 na podstawie otwornic (północna część zapadliska przedkarpackiego)

Abstract

FORAMINIFERAL BIOSTRATIGRAPHY OF THE MIOCENE DEPOSITS FROM THE BUSKO (MŁYNY) PIG-1 AND KAZIMIERZA WIELKA (DONOSY) PIG-1 BOREHOLES (NORTHERN PART OF THE CARPATHIAN FOREDEEP) Abstract. Micropaleontological study of Miocene deposits from the Busko (Mlyny) PIG-1 and Kazimierza Wielka (Donosy) PIG-1 boreholes, located in the northern part of the Carpathian Foredeep, has allowed taxonomic and biostratigraphic characteristics of foraminiferal assemblages. The samples were taken from clay and clay-marly interbeds in sub-evaporitic, evaporitic and supra-evaporitc complexes. In the Busko (Mlyny) PIG-1 borehole, five foraminiferal assemblages have been defined (Z.b.I–Z.s.V), corresponding with the following foraminiferal zones: Orbulina suturalis / Praeorbulina – Z.b.I (Moravian substage of the Early Badenian), Neobulimina longa – Z.b.II; Velapertina indigena – Z.b.III, Hanzawaia crassiseptata – Z.b.IV (Kosovian substage of the Late Badenian) and Anomalinoides dividens – Z.b.V (Volhynian substage of the Early Sarmatian). In the Kazimierza Wielka (Donosy) PIG-1 borehole, two foraminiferal assemblages have been identified (Z.b.I and Z.s.II), correlated with following foraminiferal zones Velapertina indigena – Z.b.I (Kosovian substage of the Late Badenian) and Varidentella sarmatica – Z.s.II (Volhynian substage of the Early Sarmatian). The third assemblage (Z.s.III), because of poor preservation of foraminifers has been attributed to the Sarmatian stage in general. Lateral replacement of planktonic and benthonic foraminiferal assemblages confirms a significant facies variability of the Late Badenian deposits that accumulated in the northern margin of marine basin in the Carpathian Foredeep.