TY - JOUR ID - 135461 TI - Investigation of Origin, Sedimentary Environment and Preservation of Organic matter: A Case Study in Garau Formation JO - Iranian Journal of Oil and Gas Science and Technology JA - IJOGST LA - en SN - 2345-2412 AU - Hemmati, Meisam AU - Ahmadi, Yaser AD - M.S. Student, School of Geology, College of Science, University of Tehran, Tehran, Iran. AD - Assistant Professor, Chemical and Petroleum Engineering Department, Ilam University, P.O. Box 69315/516, Ilam, Iran. Y1 - 2022 PY - 2022 VL - 11 IS - 1 SP - 1 EP - 15 KW - Elemental Analysis KW - Garau Formation KW - Sedimentary Environment KW - visual kerogen analysis DO - 10.22050/ijogst.2021.291679.1601 N2 - Knowing the characteristics of suitable environments for precipitation of oil prone source rocks facilitates oil explorations and leads to development of oil fields. The current study investigates the organic matter properties and sedimentary environment conditions of the Garau Formation in various outcrop sections in Lurestan province from south-west of Iran (High Zagros) with using elemental analysis, visual kerogen analysis and Rock-Eval pyrolysis data. The geochemistry parameters indicate that the Garau Formation is an excellent oil prone source rock and composed of kerogen type I and II. The oxygen index (OI) is very low which reveals that organic matter deposited in an anoxic sedimentary environment and suitable for the preservation of organic matter and hydrocarbon generation. The visual analysis of isolated kerogens from source rock samples indicates the abundance of dark amorphous organic matter (AOM) with small amounts of phytoclasts and pyrite with no palynomorphs. Sedimentation seems to have occurred in deep and reduced parts of a carbonate basin during a rapid transgression. In addition, due to the effect of thermal maturation, the color of amorphous organic matter has darkened. The elemental analysis and Van-Krevelen diagram was shown that the type of organic matter and reveals the thermal maturity of the oil window. Moreover, amount of pyritic sulfur (Sp) and organic sulfur (So) contents have been calculated, and it was reveals that the high content of organic sulfur is a key element in the structure of organic matter. UR - https://ijogst.put.ac.ir/article_135461.html L1 - https://ijogst.put.ac.ir/article_135461_a207c46ca0c48e8f65ef0411feda1de9.pdf ER -