Maastrichtian-Thanetian planktonic foraminiferal biostratigraphy and remarks on the K-Pg boundary in the southern Kocaeli Peninsula (NW Turkey)

Authors : Volkan SARIGÜL, Aynur HAKYEMEZ, Okan TÜYSÜZ, Şengül Can GENÇ, İsmail Ömer YILMAZ, Ercan ÖZCAN

Pages : 1-29

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Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The Kocaeli Peninsula insert ignore into journalissuearticles values(NW Turkey); provides one of the best exposed deep marine Upper Cretaceous-Palaeocene sections in north-western Anatolia. The biostratigraphic framework from three sections, namely Belen, Bulduk, and Toylar, in the southern part of the Kocaeli Peninsula is established by means of planktonic foraminifera. A very rich planktonic foraminiferal assemblage analysed both in thin sections and washed residues records a biozonation ranging from the Contusotruncana contusa insert ignore into journalissuearticles values(CF6); Zone insert ignore into journalissuearticles values(Maastrichtian); to the Globanomalina pseudomenardii insert ignore into journalissuearticles values(P4); Zone insert ignore into journalissuearticles values(Thanetian);. Although a major part of the biozones in the studied interval is clearly defined, the upper three zones insert ignore into journalissuearticles values(CF1-3); of the latest Maastrichtian and the P0 and P1a zones of the earliest Palaeocene cannot be recognised. These unrecorded biozones are either completely missing or occurred within a very condensed interval in the studied sections. A hardground layer characterised by oxidation and extensive bioturbation might indicate a possible biostratigraphic gap spanning the CF1-3 zones of the uppermost Maastrichtian in the Belen and Bulduk sections. In the Toylar section, on the other hand, the CF1-3 zones still cannot be detected although a hardground layer is not observed. The biostratigraphic resolution across the Cretaceous-Palaeogene insert ignore into journalissuearticles values(K-Pg); boundary in the studied sections cannot be improved due to the condensed and well-cemented pelagic carbonates of the boundary interval.
Keywords : Kocaeli Peninsula, NW Turkey, Upper Cretaceous, Palaeocene, planktonic foraminifera, biostratigraphy