Biostratigraphy, microfacies and Sequence stratigraphy of Sachun Formation and Correlation with Paleoecology in the Outcrops around Shiraz (SW of Iran)

Document Type : Original Article

Authors

• Kamal Karimi ¹
• Massih Afghah ²
• Seyed Hossien Ghetmiri ³
• Mohammad Bahrami ⁴

¹ Ph.D. Student in Paleontology & Stratigraphy, Department of Geology, Faculty of Science, Shiraz branch, Islamic Azad University, Shiraz, Iran

² Associate Professor, Paleontology & Stratigraphy, Department of Geology, Faculty of Science, Shiraz branch, Islamic Azad University, Shiraz, Iran

³ Assistant Professor, Department of Geology, Faculty of Science, Shiraz branch, Islamic Azad University, Shiraz, Iran

⁴ Assistant Professor, Payame Noor University Faculty of Science Center of Shiraz, Fars, Iran

10.22067/sed.facies.2022.69043.1000

Abstract

The is studied already of the Sachun Formation around the Shiraz (Interiorl Fars zone) in the southwest of Zagros basin has been studied in terms of biostratigraphy, the paleoenvironment (based on stratigraphic data of feraminifers) and sequence stratigraphy. Two biozones of framinifiers were determined in three sections (Tang-e- khiyare, Dariyan and Kohenjan). The age range of Sachun Formation in the studied sections is from Lower Paleocene to Lower Eocene.The Sachun Formation in the studied area is conformably overlaid on the Pabdeh Formation and underlaid the Jahrum Formation. Qorban member as carbonates sequence in the Sachun Formation, with the accumulation of more fossils and prominent outcrops deposited in a bioclactic barrier, can be distinguished from other units of the Sachun Formation. Based on observations and laboratory study, eight microfacies were identified in four sedimentary environments. The sequence of the Sachun Formation was deposited in a carbonate-clastic platform. Comparison of paleoecologic and paleoenvironment of both three studied sections represent Qorban member of Kuhenjan section was deposited in shallow water and high energy environment proportion of Dariyan section. Actually, fossil diversity is more recognized in oligotrophic and mesotrophic environments of Dariyan section whereas fossil diversity ismore than Qorban member of Kuhenjan section. The Sachun Formation is deposited in a shallow water. The Sachun Formation of the studied sections as Paleocene-Eocene age consists of two third-order sequences.

Keywords

• Sachun Formation
• Interior Fars
• Biostratigraphy
• Paleoenvironment
• Sequence Stratigraphy

Main Subjects

• Systematic Paleontology & Biostratigraphy
• Microfacies and Sedimentary Environments
• Lithostratigraphy, Sequence Stratigraphy and Magnetostratigraphy

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