Biostratigraphy of Campanian – Maastrichtian & Danian on the based of plankton foraminifera in Galanderud area, northern flanks of Alborz mountains
Subject Areas :Roza Khajehtash 1 , Behrouz Darvishzad 2
1 - کارشناس ارشد دانشگاه آزاد اسلامی واحد علوم و تحقیقات تهران
2 - استادیار گروه زمین شناسی دانشگاه شهید بهشتی
Keywords: Biostratigraphy, Cretaceous-Tertiary boundary (K/T), planktonic foraminiferal,
Abstract :
In central Alborz Mountains in north of Iran, a new Cretaceous-Tertiary boundary (K/T) section near GalanderudMine in Mazandaran province reveals diversity of planktonic foraminiferal the fauna similar to those found inElKef & Elles in Thunisia.The Cretaceous-Tertiary boundary is located by planktionic foraminifera with in a narrow interval bounded bylast appearance of tropical and subtropical Cretaceous species and first appearance of small Tertiary species. InGalanderud section only 5 species survived after the Cretaceous-Tertiary boundary event and 31 species ofCretaceous became extinct in or before Cretaceous-Tertiary boundary. The Maastrichtian species that seem todied out gradually are generally large and cosmopolitan.