Examination of Sedimentary Facies and Diagenesis of the Eocene Deposits in Saravan, Southeastern Iran
Keywords:
Sedimentary facies, Foraminifera, Diagenesis, Eocene, Saravan, Sedimentary environmentAbstract
The study area is located north of Saravan County, covering the regions from Ghasht toward Sib Soran. Stratigraphic sections of Ghasht and Sib Soran were measured and sampled to describe facies and determine the sedimentary environment. In this area, major clastic and carbonate facies groups were identified. The region includes layers of sandstone, limestone, marl, and shale. The limestones contain benthic foraminifera such as Nummulites and Alveolina, along with other skeletal and non-skeletal components. Based on the presence of key benthic foraminiferal species, an Eocene to middle Eocene age is proposed for the area. Facies include microconglomerates, sandstones, and shales, exhibiting fining-upward trends in grain size, indicative of a marine setting with turbiditic facies. Microscopic studies further reveal that the sediments in this area are composed of carbonate facies. These facies are associated with the facies belts of lagoon, shoal, and shallow open marine environments. Based on facies characteristics and the abundance of allochems, the depositional environment of this region is interpreted as a shallow marine setting with a gentle slope. Analysis of diagenetic processes in the region highlights various processes such as micritization, cementation, compaction (mechanical and chemical), dissolution, and the filling of fractures and pores. This study, based on fieldwork alongside laboratory results, aims to investigate the sedimentary facies, diagenesis, and sedimentary environment of the Saravan region in southeastern Iran.
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