Nannoplankton biostratigraphy of the Selendian-Ipresian Güney Formation (Ulukışla Basin) and sea-water temperature changes in this period [en]

Abstract

In this research, nannoplankton flora of Selandian-Ypresian Güney formation which is comprised of sandstone-shale intercalation and cropping out in Ereğli – Ulukışla basin was studied. 44 species of 16nannoplankton taxons were determined in 50 samples collected from Güney measured stratigraphic section. Flora of five nannoplankton zone [(Fasciculithus tympaniformis Zone (late Selandian), Heliolithus kleinpelliiZone (late Selandian – early Thanetian, Heliolithus ridelii Zone (Thanetian), Discoaster multiradiatus Zone(Thanetian), Tribrachiatus contortus Zone (Ypresian)] were determined. Of the nannoplankton species which are sensitive to temperature changes, Coccolithus eopelagicus indicate mild – cool water and Discoaster andSphenolith indicate mild-warm water environments; based on this information, we suggest that the sea waterduring the Selandian was mild to warm, during the Thanetian, the sea water was mild to cool and during the Ypresian, again the mild to warm seawater conditions prevailed.