Comparison of ΔlogR and mineralogy-based methods in estimating organic carbon content of Pabdeh formation in Ahwaz and Rag-e Sefid oilfields
Subject Areas : PetrophysicsMahdi Shafie 1 , Seyed Hassan Tabatabaei 2 , Morteza Tabaei 3 , Nader Fathianpour 4 , Ali Opera 5
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Keywords: Organic carbon content, Source rock, Ahwaz field, Rag-e sefid field, ΔlogR method, Mineralogy based method,
Abstract :
One of the most common and relatively accurate methods for determining the amount of organic carbon in rocks in the oil and gas exploration potential is the Pyrolysis family, a standard example of which is the first rock pyrolysis method. Based on the study of the core, this method explores the potential of oil and gas resources in rocks. One of the important and valuable parameters in determining the potential of oil and gas resources is the determination of TOC. The purpose and motivation of this research is to compare the ΔlogR method and the mineralogy-based method for calculating the total amount of organic carbon in the source rock. It has the desired accuracy and relatively low cost. The fields studied in this study are two fields of Ahwaz and Rag-e sefid. These fields are among the potential fields of southwestern Iran for more detailed investigation and estimation of organic carbon content. In this research, software studies have been performed through IP software, using which the petrophysical data of each field have been calculated and compared, and finally, its results have been compared with actual TOC values. Input data in the mineralogical data method include density log, neutron porosity log and gamma log, and input data in the ΔlogR method include acoustic and resistivity logs. According to the fields, the most appropriate methods (in terms of R2) in Ahwaz and rag-e sefid fields are the mineralogical data method and the ΔlogR method, respectively. Also, in terms of cost, precision and accuracy parameters, the best method discussed in this research is R2 mineralogical data in Ahwaz and Rag-e sefid, 0.94 and 0.61, respectively. After this, the ΔlogR method comes second.
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