Nannostratigraphy of Gurpi Formation in Dare- Shahr Section (SE Ilam)

Nannofossils are good for biostratigraphy, since they are abundant, planktonic, rapidly evolving and largely cosmopolitan, especially in the Late Cretaceous. For these reasons and due to the lack of any precise paleontological study, the nannofossils of the Gurpi Formation were investigated in Dare-Shahr. This formation consists of marl and shale and two members (Lopha and Emam Hassan limestones). In this study, for the first time, ۲۴ genera and ۴۸ species of nannofossils were identified. According to the stratigraphic distribution of calcareous nannoplanktons, the study section is of Late Santonian to Early Danian age, corresponding to CC۱۶-CC۲۶ (Sissingh ۱۹۷۷) and NP۱-NP۲ (Martini ۱۹۷۱). The presence of Biantolithus sparsus, Cruciplacolithus primus, Micula prinsii, indicates that the K/T boundary continues and within the Gurpi Formation in the Dare-Shahr section.

کلیدواژه ها:

nannofossils ، Nannoplanktons ، Lopha ، Gurpi Formation ، Dare-shahr ، Ilam