Microfacies and sedimentary environment of the Asmari Formation in Rag-e-safid oil field, south west Khouzestan

Asmari Formation (oligo-Miocene) is the most important reservoir unit in south west of Iran oil Fields. The Rag-e-Safid oil field is one of them. This field is located in Dezful Embayment. In several studies, there are still some uncertainty about microfacieses and depositional environment of the Asmari formation in Rag-e-safid oil field. There for according to petrographical study of thin sections supplied of cores and cutting samples (2138 thin sections with 7 wells) and comparison of associated constituent facieses with standard microfacies types of carbonate ramps of Flugel (Flugel, 2004) and facies belts of Buxton and Pedley (Buxton and Pedley, 1989), 13 carbonate microfacieses and 2 non carbonate microfacieses is investigated. The microfacieses are in five group facieses (depositional sub environment) that consist of open marine (group O), shoal or bar (group B), lagoon (group L), intertidal (group I) and supratidal (group S). The sub environment ascribed to a carbonate platform ramp.