Biostratigraphy of the late Eocene-Miocene (Jahrum & Asmari Formations) in the west and southeast of the Shahr-e kord (Central Zagros)


1 PhD. student, Department of Geology, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran

2 Department of Geology, Khorramabad Branch, Islamic Azad University, khorramabad, Iran.

3 2Department of Petroleum Engineering, Masjed Soleiman Branch, Islamic Azad University, Masjed Soleiman, Iran

4 Department of Geology, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran

5 1Department of Geology, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran


Jahrum Formation has deposited Paleocene to Eocene in Zagros Basin (mainly Fars area). At the first time, the type section of this formation was introduced in the Tang-e-Ab at the northern limb of Jahrum Mount by James and Wynd (1965). In the type section, Jahrum Formation is located on the Sachun Formation with a conformable contact and has discontinuous contact with the Asmari Formation at the top (Motiei.1372). The carbonate Asmari Formation Oligocene to Miocene age, is the most important reservoirs rock of Basin Zagros. Richardson (1924) measured the type section of this formation in Asmari Mount (Tang-e-Goltorsh). Asmari Formation has different characteristics lithostratigraphy and biostratigraphy at the different parts of Zagros Basin. The studied sections have not been investigated biostratigraphy formations, So far. In this research, an attempt has been made to study biostratigraphy, presentation suitable biozones, and determinate age’s deposits of Asmari and Jahrum formations, in Isa Abad and Imamzadeh Gahroo sections in Central Zagros.


Main Subjects

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