Effect of salt tectonics on theKourdeh Anticline on the thickness varriations, facies, depositional environment and diagenesis of the Sarvak Formation (Fars, Zagros)

In order to understand the impact of salt plug on facies, depositional environment and diagenesis of the Sarvak Formation in the Kourdeh Anticline, three sections close to the salt plug measured and studied. The thickness of Sarvak Formation in three sections are 25 (close the salt plug), 90 and 185m (away from the salt plug) and is composed of limestone. Based on facies analysis and petrography, 11 microfacies identified. Microfacies analysis, high dip of sediments, differences in thickness, reducing of interbedded shale and shallowing environment toward the salt plug show that the Sarvak Formation deposited in three facies belts including outer, middle and inter shelf. Approaching to the salt plug, facies are shallower so that tidal flat facies have been in the margin of salt plug and deeper facies formed away from the salt plug. Digenetic processes affected this formation include micritization, neomorphism, dissolution, compaction, fracture, replacement (silicification, dolomitization, hematitization and pyritization) and cementation (equant, darusy, blocky, overgrowth and isopachous). The salt plug caused changes such as fracture and dolomitization of the bioclasts, reduction of dissolution, increases compaction and silicification that are operated in three Eogenetic, mesogenesis and telogenetic stages