Investigation of microfacies, sedimentary model and organic geochemical properties of Garau Formation in Khorram Abad anticline


Department of Geology, Faculty of Basic Sciences, University of Lorestan, Khorram Abad, Iran


In order to study, biostratigraphy, Sedimentary environment and biogeochemistry of Garau Formation studied at one stratigraphical section at the KhorramAbad anticline. This section has a thickness of 137.5 meters. Study of microfacies sections of the Early Cretaceous Formation of the Garau Formation and study of paleontological and histological characteristics of specimens including abundance of skeletal and non-skeletal alocomas, cement, detrital particles and matrix resulted in the identification of 8 microfacies in the deep-sea region in the study area. Also the proposed sedimentary model of the Garau Formation is based on carbonate platform microfacies determined by ramp type. In this research, the geochemical characteristics of the Garau Formation in the Khorramabad anticline were done by Rock-eval method. Based on the analysis of existing data, type III kerogen was studied. The TOC of samples from this rock unit is relatively weak and varies from about 0.24 to 1.28 . Garau Formation samples in Khorramabad anticline have low potential for hydrocarbon production. Since the hydrogen index of the Garau Formation samples is between 50-250 mgHc/gRock, so the potential of the Garau Formation in these samples seems to be more focused on the production of light (gas) hydrocarbons.


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