Himalayan Geology, Vol. 42 (1), 2021, pp. 155-162, Printed in India

Biostratigraphy of Santonian-Maastrichtian pelagic sediments (Gurpi Formation) by using Globotruncanids in Nowdan Anticline, Zagros mountains, Iran

MOHAMMAD REZA ESMAEILBEIG

Department of Geology, Shiraz Branch, Islamic Azad University, Shiraz, Iran

Email: r.esmaeilbeig@gmail.com

Abstract: The Gurpi Formation is a sequence of pelagic sediments belonging to Late Cretaceous Epoch and holds a significant status in the petroleum geology of the Zagros basin. In order to study the biostratigraphy, a shale dominated section was selected in the West of Shiraz in Nowdan anticline. The study of Globotruncanids of this section, led to find eight biozones from Santonian to late Maastrichtian: biozone I (Dicarinella asymmetrica zone) belongs to Santonian. Biozones II (Giobotruncanita elevata zone), and III (Globotruncana ventricosa zone) represent the Early and Middle to Late Campanian. Biozones IV (Globotruncana falsostuarti zone), V (Globotruncanella havanensis) and VI (Globotruncana aegyptiaca) represent the Late Campanian. Biozones VII (Gansserina gansseri zone) suggests the Late Campanian to Early Maastrichtian and biozone VIII (Contusotruncana contusa zone) represents the Early to Late Maastrichtian.

Keywords: Gurpi Formation, Upper Cretaceous, Biozonation, Globotruncanids, Zagros, Iran.