Author(s)

Masoud Asgharian Rostami, Mohammad Vahidinia, Ebrahim Ghasemi-Nejad, Abbas Sadeghi

Faculty of Science, Department of Geology, Ferdowsi University of Mashhad, Mashhad, Iran.
Faculty of Science, Department of Geology, Shahid Beheshti University, Tehran, Iran.
Faculty of Science, Department of Geology, University of Tehran, Tehran, Iran.

High resolution sampling across the Cretaceous/Paleogene boundary (K/Pg) at the Galanderud section in northern Iran provides the most expanded and continuous section for us to consider biostratigraphy and the mass extinction pattern of Cretaceous planktic foraminifera. Based on planktic foraminifera, four biozones and five sub-biozones have been identified across the K/Pg boundary. These biozones include the Abathomphalus mayaroensis Biozone (Plummerita hantkeninoides subbiozone), the Guembelitria cretacea Biozone (including two sub-biozones: the Hedbergella holmdelensis and the Parvularugoglobigerina longiapertura), the Parvularugoglobigerina eugubina Biozone (including two subbiozones: the Parvularugoglobigerina Sabina and the Eoglobigerina simplicissima) and finely the Parasubbotina pseudobulloides Biozone. Planktic foraminiferal extinction occurred over a brief period, with 3% of the species disappearing in the late Maastrichtian, and 72% of the species becaming extinct at the K/Pg boundary. About 25% of the species survived into the early Danian. Extinction of 73% of the species at the K/Pg boundary is very compatible with the effect of a large asteroid impact.

Biostratigraphy; Mass Extinction Pattern; Cretaceous/Paleogene Boundary; Northern Alborz; Iran

Asgharian Rostami, M. , Vahidinia, M. , Ghasemi-Nejad, E. and Sadeghi, A. (2013) Biostratigraphy and Mass Extinction Pattern across the Cretaceous/Paleogene Boundary, Northern Alborz, Iran. Open Journal of Geology, 3, 33-38. doi: 10.4236/ojg.2013.31005.