Microfacies and depositional environment of theAsmari Formation of the Bandar-pol anticline, Zagros Basin, South of Iran


A. Hashmie, A. Najafie, P. Rezaei, M. Ghorbanie
Department of Geology, Faculty of Science, Hormozgan University,



Abstract:
The Asmari Formation (Oligocene-Miocene), a thick carbonate succession of shallow-
water carbonates of the intrashelf basin deposits of Zagros Mountains, has been studied to
determine its microfacies and paleoenvironments. In the study area (Bandar-pol anticline), the
Asmari Formation is subdivided into nine microfacies that are distinguished by petrographic
analysis on the basis of their depositional textures and fauna. Consequently, five major
depositional environments were identified in the formation. Based on the paleoecology and
lithology, five distinct depositional settings can be recognized: tidal flat (MF1), lagoon (MF2-3-
4), shoal (MF5), restricted (MF6) and open marine (MF7-8-9). Based on the environmental
interpretations, a ramp consisting of inner and middle parts prevails.

Keywords: Asmari Formation; Bndar-pol anticline; Microfacies; Carbonate ramp.



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