Prediction of Source-Rock Facies Variations in the Persian Gulf Oils:Using S/N Ratio


1 Associate Professor, Department of Petroleum of Engineering, Amirkabir University

2 PhD Student in Petroleum Exploration Engineering, Amirkabir University


      The use of sulfur and nitrogen abundance is one of the useful parameters in classification of oil samples in a sedimentary basin. It also indicates variations of facies of source rock in a basin. Presence of clay minerals in source rock in the oil generated reduces sulfur and increases nitrogen contents. Most of the Persian Gulf oils can be classified as “high sulfur” oils. Kharg, Dorood and Hendijan oil fields have the highest percentage of sulfur and Resalat, Reshadat, Salman and Balal oil fields have the lowest contents of sulfur. Most of oil samples in the Iranian sector of the Persian Gulf have sulfur/nitrogen ratio higher than 5. This ratio shows that most source rocks in the Persian Gulf have marly facies which deposited in a pelagic environment. Evaporite facies increases in source rocks in the western and northwestern region. Also, Shale facies increases in the eastern and southern regions.


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