Document Type : Original Research Paper

Authors

1 Ph. D. Student, Department of Geology, Faculty of Basic Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Professor, Department of Geology, Faculty of Basic Sciences, Damavand Branch, Islamic Azad University, Damavand, Iran

3 Assistant Professor, Department of Geology, Faculty of Basic Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran

4 Associate Professor, Department of Geology, North Tehran Branch, Islamic Azad University, Tehran, Iran

5 Ph. D., Departement of Paleontological Studies and Researches, Exploration Directorate of NIOC, Tehran, Iran

Abstract

Lithostratigraphy and biostratigraphy studies on the Sarvak Formation in type section (Tang- e Sarvak, Northwest of Behbahan) show that this Formation has 710 meter thicknesses that divided in to four lithostratigraphic units. The Sarvak Formation in type section rests on the Kazhdumi Formation conformably with gradational contact (black shales and black argillaceous limestone) and under the Gurpi Formation with disconformity boundary. In this study 8 genus and 9 species of planktonic foraminifera and 34 genera and 33 species of benthic foraminifera have been reported. Four biozones based on (wynd, 1965) and two biozone based on) Premoli Silva and Verga 2004) have been reported as follow; Four biozones based on Wynd 1965:  1- Favusella washitensis range Zone # 23,2- '' Oligostegina''  facies  # 26,3- Rudist debris # 24, 4- Nezzazata– Alveolinids Assemblage Zone #  25, Tow biozones based on Premoli Silva and Verga 2004: 1-Muricohedbergella planispira Zone, 2-Ticinella primula Zone. It can propose an Albian- Cenomanian age for Sarvak Formation based on these biozones and also it can recognize Albian-Cenomanian boundary on occurrence of Muricohedbergella planispira and Whiteinella sp. in lower part of this Formation.

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