The First Record of Microcodium from Maastrichtian Kalat Formation, Kopet-Dagh Sedimentary Basin, NE Iran: Biostratigraphy and Microfacies

Abstract

This paper is to present the biostratigraphy of the Maastrichtian Kalat Formation in Karnaveh area of the northeastern Iranian Kopet-Dagh sedimentary basin. Micropaleontological studies have led to the determination of micro-calcite structures, having Microcodium deposited in the stratigraphic section due to transgression and regression of the sea. On the basis of determined benthic foraminiferal taxa Laffitteina mengaudi (Astre), Lepidorbitoides socialis (Leymerie), Omphalocyclus macroporus (Lamarck), Orbitoides apiculata Schlumberger, Orbitoides media (d’Archiac), Rotalia skourensis Pfender, Siderolites calcitrapoides Lamarck, Sirtina orbitoidiformis Brönnimann & Wirz, Sulcoperculina cosdeni Applin & Jordan, Sulcoperculina globosa Cizancourt and Sulcoperculina vermunti (Thiadens), Kalat Formation in the studied stratigraphic section is assigned to the Maastrichtian. The current study represents the first record of Microcodium occurrence in Kopet-Dagh sedimentary basin in northeast Iran, expanding the current knowledge on its palaeogeographical distribution in Tethyan Realm.