Microfacies, sedimentary environment and diagenetic processes of carbonate rocks of the Asmari Formation( Chenareh Anticline, South Lorestan)

In order to understand the sedimentation history of carbonate rocks of Asmari Formation, a 145 m thick stratigraphic section was selected in the south of Lorestan. The lithology of this periodic formation is from thin-layer, middle-layer limestones, thick to very thick-layered. The samples taken from this section are 145 samples that were examined in terms of sedimentary environment and diagenetic processes based on field evidence and studies of thin microscopic sections and due to the absence of evidence such as the construction of bird eyes. , Stromatactis cavities, Typical structures, Intracellular components, Evaporative minerals and the absence of traces and structures resulting from sediment drying as well as the absence of slippery and sedimentary sediments (turbidites, intraclasts and sections) Finally, it led to the identification of 7 micro-defects related to 4 lagoon facies belts, dam, restricted section (middle ramp) and internal ramp. In this section, several diagenetic processes such as micriticization, morphology (increasing and decreasing), cementation (coaxial cement, fibrous thickness, dimensional, block, joint and kilotopic dynamics), compaction (mechanical and chemical), dissolution (dependent To fabric and non-fabric dependent), substitution (pyritization, silicification and dolomitization) and diagenetic modeling. Based on petrographic evidence, the paragenetic sequence of Asmari Formation deposits in this section has been interpreted in four marine environments, freshwater, burial and uplift. Three stages of diagenesis, namely primary diagenesis (eogenesis), middle diagenesis (mesogenesis) and final diagenesis (telogenesis) have been determined for the studied deposits.