Oil-source rock correlation in super-giant Gachsaran oilfield

Geochemical investigation of Kazhdumi and Pabdeh formations suggest a shaly and carbonate lithology as well as a suboxic-anoxic marine depositional environment for both formations. On the other hand, the thermal maturity of the Kazhdumi Formation is equivalent to the mid of oil window while thermal maturity-related parameters show that the Pabdeh Formation has not entered the oil window. Biomarkers are indicative of derivation of the four oil samples from a carbonate-shaly or marly source rock. Also, thermal maturity-related biomarkers reflect a peak mature stage for all of the four samples. Different values of oleanane index in oil samples is implying a more significant role of the Pabdeh Formation in hydrocarbon embedded in 36, 56, 55 wells in compare to well number 22. In general, oil-source correlation introduces both Kazhdumi and Pabdeh formations as source rocks for the crude oils.