Investigation of facies, sedimentary environment and stratigraphy of evaporite-carbonate sequence of Asmari in Bangestan Anticlines, Putu and Parsi oil field, Zagros sedimentary basin, SW Iran

Asmari Formation is the first known carbonate reservoir rock in the world and the largest oil reservoir rock in the Zagros sedimentary basin. This formation has a significant expansion in the Dezful Embayment and Izeh areas. In this study, the main focus has been on the stratigraphic position of Basal Anhydrite of Asmari Formation. In this study, the main focus on the stratigraphic position of the basal anhydrite section has been the rule of Asmari Formation, so in three stratigraphic sections (surface sections of Putu mountain and Bangestan mountain as well as subsurface section of well 19 of Parsi oil field) An attempt has been made to study the status of this sequence. Based on field descriptions and lithographic changes, these sections have been done from old to new.Due to the similarity of these rock units, both in terms of location and time, in the study area, the features of the facies and their environment have been briefly reconsidered from old to new.The transition from the sequence of green marls and dolomite limestone consisting of marine facies related to the relatively deep and low-energy marine environment environment, to the sequence of medium limestone of the packstone - grainstone ooid and Favreina facies it shows the shallowness of the sedimentary basin of the end parts of Pabdeh Formation towards the base of Asmari Formation, which is ultimately associated with the formation of planar stromatolite facies.