High Resolution Sequence Stratigraphy and Depositional Environment of Pabdeh Formation in Dashte – Arjan Area (Shiraz, Fars, Zagros, Iran)

Pabdeh shaly formation (Paleocene-Oligomiocene) has been expanded in Fars, Khozestan and Lorestan. The lower lithostratigraphic limit of this formation in Shiraz area is distinguished from Gurpi formation by purple shale. Its upper limit is gradational and conformable with Asmari formation. In order to study sequence stratigraphy and microfacies of Pabdeh formation in Shiraz area, one stratigraphic section have been chosen (Zanjiran section). Petrographic studies resulted in the identification of 9 pelagic and calciturbidite microfacies. The calciturbidite microfacies have been formed when the sea level was high, the rate of carbonate deposition was high and it slumped into the deep marine. Sequence stratigraphy studies show that Pabdeh formation in the studied zone consists of two depositional sequences (DS) that the lower contact is erosional (purple shale - type one, SBI or type two, SB2) and the upper contact is correlative conformity (type two, SB2).

Authors:

• Mirzaee Mahmoodabadi Reza
• Afghah Massih
• Saeedi Somaye

Keywords:

• Pabdeh formation
• Shiraz
• Microfacies
• Purple Shale
• Zanjiran Section
• Sequence Stratigraphy

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