Lithostratigraphy, Microfacies and Paleoenvironmental Reconstruction of the Jahrum Formation in the West and Northwest of the Bandar Abbass Area, South Iran

The Jahrum formation is one of the most important reservoirs in the Zagros basin. In this research, the Jahrum formation in west and northwest Bandar Abbas area has been investigated. The thickness of this formation in the studied area in Anguru Section is about 341m, of which, based on paleontological studies, 167m belong to Lower and Middle Eocene and 174m is assigned to Late Eocene. The lower contact of this formation with the Pabdeh formation is gradational and the upper contact with the Asmari formation is paraconformable. The Jahrum formation in the studied section is lithologically consists of fossiliferous limestone and medium to thick layer beige to gray dolomitic limestone. Based on the field and petrographic studies, 6 types of microfacies and 6 subfacies have been identified in the studied interval of the Jahrum formation. These microfacies have been deposited in 3 standard facies belt, including lagoon, Nummulites Bank, and open marine environment. These microfacies have been deposited in a distally steepened ramp.