Determination and applications of chemical analysis to evaluate Jurassic hydrocarbon potentiality in Northern Iraq

Chemical analysis was carried out to evaluate the potentiality of rock samples having hydrocarbon characteristics, identified by chemical methods as one of the approaches to evaluate the source rocks encountered from Sehkanian, Sargelu, Naokelekan, Sarmord and Ghia Gara of (Middle to Upper Jurassic–Lower Cretaceous) stratigraphic sequence of Iraq, representing source rocks, which are recovered from oil exploratory wells Butmah-15, Ajeel-8, Makhul-2, Qarachuq (1 and 2) and TaqTaq-1 (Bm-15, Aj-8, Mk-2, Qc-1,Qc-2 and Taq-1) alternatively, located in the northern part of Iraq and also the outcrop samples extracted from the type locality at Surdash Anticline. Additional samples were taken from another exposure section of the Jurassic rocks from Banik village, those various samples represent Varity of palynofacies. The bulk of chemical analysis enables to enhance the potentiality of the source rocks, leading to believe generating tremendous amount of oil and subordinate gas promising more than earlier predictions for forming super giant oil and thermogenic gas fields in this area. The value of the production indices determines that the system of the oil in Iraq is not widely different from the depocenters of the surrounding countries. Accordingly Iraq is considered as an ideal and systematic basin that all the total petroleum system elements are available, giving indications of good source rocks, extensive reservoirs and excellent seals. Typical oil fields, which as determined by the remarkable total organic carbon exceeds 20 %, and maturation evidences accompanied with maximum temperature up to 450°C indicate obviously various values of the hydrogen and oxygen indices, kerogen type II and type III, of marine to mixed to terrestrial origin that lead to determine that the oil and gas prone Sargelu, Naokelekan and Ghia Gara were good source rocks. Meanwhile Barsarin and Sarmord were reservoir rocks. The area of study is widely promising to produce oil with condensed gas.