Facies analysis and depositional environments of the OligoceneeMiocene Asmari Formation, Zagros Basin, Iran  

作　　者：Mohammad Sahraeyan Mohammad Bahrami Solmaz Arzaghi 

机构地区：[1]Department of Geology, Khorasgan (Esfahan) Branch, Islamic Azad University,Esfahan, Iran [2]Department of Geology, Fars Science and Research Branch, Islamic Azad University,Shiraz, Iran

出　　处：《Geoscience Frontiers》2014年第1期103-112,共10页地学前缘（英文版）

摘　　要：The Asmari Formation （a giant hydrocarbon reservoir） is a thick carbonate sequence of the Oligocene Miocene in the Zagros Basin, southwest of h＇an. This formation is exposed at Tang-e-Lendeh in the Fars interior zone with a thickness of 190 m comprising medium and thick to massive bedded carbonates. The age of the Asmari Formation in the study area is the late Oligocene （Chattian）-early Miocene （Burdigalian）. Ten microfacies are defined, characterizing a gradual shallowing upward trend; the related environments are as follows： open marine （MF 8-10）, restricted lagoon （MF 6-7）, shoal （MF 3 5）, lagoon （MF 2）, and tidal fiat （MF 1 ）. Based on the environmental interpretations, a homoclinal ramp consisting of inner and middle parts prevails. MF 3-7 are characterized by the occmrence of large and small porcelaneous benthic foraminifera representing a shallow-water setting of an inner ramp, influenced by wave and tidal pro- cesses. MF 8-10, with large particles of coral and algae, represent a deeper fair weather wave base of a middle ramp setting.The Asmari Formation （a giant hydrocarbon reservoir） is a thick carbonate sequence of the Oligocene Miocene in the Zagros Basin, southwest of h＇an. This formation is exposed at Tang-e-Lendeh in the Fars interior zone with a thickness of 190 m comprising medium and thick to massive bedded carbonates. The age of the Asmari Formation in the study area is the late Oligocene （Chattian）-early Miocene （Burdigalian）. Ten microfacies are defined, characterizing a gradual shallowing upward trend; the related environments are as follows： open marine （MF 8-10）, restricted lagoon （MF 6-7）, shoal （MF 3 5）, lagoon （MF 2）, and tidal fiat （MF 1 ）. Based on the environmental interpretations, a homoclinal ramp consisting of inner and middle parts prevails. MF 3-7 are characterized by the occmrence of large and small porcelaneous benthic foraminifera representing a shallow-water setting of an inner ramp, influenced by wave and tidal pro- cesses. MF 8-10, with large particles of coral and algae, represent a deeper fair weather wave base of a middle ramp setting.

关 键 词：Asmari Formation Tang-e-Lendeh Benthic foraminifera Carbonate ramp 

分 类 号：P618.13[天文地球—矿床学]