Biostratigraphy and Paleoecological Study of Pabdeh Formation in Interior Fars, Zagros Basin, Iran


The Zagros basin, which trends NW-SE, is covered by a sea during the Paleogene, resulting in deposition of the Pabdeh Formation in the deeper parts of the basin. The thickness of the Pabdeh Formation in Tang-e-Abolhayat is about 221 m and it consists of purple shale at the base, gray shale, marl and marly limestone with a few horizons of nodular limestone toward the top. Seventy-two samples were collected and processed for nannofossil studies. Based on the identified nannofossil zones the age of the formation in Tang-e-Abolhayat is Late Paleocene-Late Oligocene (NP9-NP24). Changes in the abundance of different genera over the studied interval have resulted in identification of three ecozones: Ecozone 1 is characterized by oligotrophic conditions with an abundance of warm water taxa; Ecozone 2 marks when conditions became more eutrophic and the abundance of temperate taxa increased; Ecozone 3 represents a return to oligotrophic conditions with an increase in warm water taxa.

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Khavari Khorassani, M. , Hadavi, F. , Ghasemi-Nejad, E. and Mousavi-Harami, R. (2014) Biostratigraphy and Paleoecological Study of Pabdeh Formation in Interior Fars, Zagros Basin, Iran. Open Journal of Geology, 4, 571-581. doi: 10.4236/ojg.2014.411042.

Conflicts of Interest

The authors declare no conflicts of interest.


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