TY - JOUR ID - 50173 TI - Depositional and post - depositional analysis of the Fahliyan Formation in Lar and Khami Anticlines (Izeh zone) JO - Scientific Quarterly Journal of Geosciences JA - GSJ LA - en SN - 1023-7429 AU - Azad Shahraki, L. AU - Rahimpour Bonab, H. AU - Ranjbaran, M. AU - Kangazian, A. AD - Ph.D. Student, Department of Geology, Islamic Azad University, Science and Research Branch, Tehran, Iran AD - Professor, School of Geology, College of Science, University of Tehran, Tehran, Iran AD - Assistant Professor, School of Geology, College of Science, University of Tehran, Tehran, Iran AD - Assistant Professor, Department of Geology, Islamic Azad University, Khorasgan (Esfahan) Branch, Tehran, Iran Y1 - 2017 PY - 2017 VL - 26 IS - 104 SP - 81 EP - 94 KW - Fahliyan formation KW - Microfacies KW - Depositional environment KW - Diagenesis KW - Carbonate ramp KW - Basement Faults KW - Izeh Zone DO - 10.22071/gsj.2016.50173 N2 - The Lower Cretaceous (Neocomian) carbonates of the Fahliyan Formation are considered as important reservoir rocks in the Zagros Basin. In this study, the sedimentary successions of this formation in Lar (620m thick) and Khami (517m thick) anticlines, located in the Izeh zone, were investigated to analyze microfacies, depositional environment, and diagenetic phenomena. Based on petrographic studies, 16 microfacies related to five facies belts of tidal flat, lagoon, carbonate shoal, mid ramp and outer ramp were recognized. Grainstone microfacies were found more abundant in the Lar stratigraphic section than the Khami section. Lack of turbidite deposits and reefal facies, and transitional changing of the facies show that the Fahliyan Formation was deposited in a homoclinal carbonate ramp. Abundance of mud dominated facies and rarity of high energy facies (like shoal facies) show that the ramp was a leeward one. According to petrographic studies, the main diagenetic features of the carbonates were micritization, cementation, dissolution, neomorphism, compaction, fracturing, and dolomitization. Due to deposition in the photic zone and high sedimentation rate, the thickness of the Fahliyan Formation in both stratigraphic sections is considerable, but based on the drawn isopach map, the thickest succession of the formation is found in the Lar section. Therefore, the Lar area is considered as the depocenter of the Fahliyan Formation. Difference in the thickness of the Fahliyan successions of Lar and Khami, most probably, is caused by the syndepositional activity of the north-south trending basement faults (like Kazeroon fault) in the region. Also, difference in the quantity of the burial compaction of the carbonate successions (caused by facies and diagenetic differences) played a role in secondary (burial) thickness changes.   UR - http://www.gsjournal.ir/article_50173.html L1 - http://www.gsjournal.ir/article_50173_7d745cca243a23327d38db36f27f38bc.pdf ER -