Evaluation of hydrocarbon potential and depositional environments of the Laffan Formation in the Binak Oilfield

In this study, the hydrocarbon potential and depositional environments of the Laffan Formation in the Binak Oilfield is investigated. Rock-Eval pyrolysis results indicate that the Laffan Formation contains a mixed type II/III kerogen. Based on the classification of the source rock in terms of total organic carbon (TOC) content, the Laffan Formation can be classified as a good to very good source rock. According to the plots of S1+S2 versus TOC, the Laffan Formation has weak to excellent hydrocarbon potential in the Binak Oilfield. However, organic petrographic inspections showed that the main components of the organic matter are inertinite, bituminite along subordinate amounts of amorphous organic matter. The predominance of Inertinites together with minor Liptinites confirms the type II and IV kerogen mixture in the studied formation. It is noteworthy that the presence of bituminite has a noticeable impact on the results of Rock-Eval pyrolysis. Therefore, in this study, the organic geochemistry of the Laffan Formation was evaluated using organic petrographic results. Accordingly, it is concluded that the organic matter in the Laffan Formation consists mainly of inertinite and bituminite with minor amounts of Liptinites. Therefore, significant hydrocarbon generation potential cannot be expected from this formation in the Binak Oilfield. Considering the public shape of the chromatograms obtained from PY-GC analysis, which show that the initial depositional environment of the Laffan Formation was predominantly oxic marine. The results of this study can be useful for better understanding the Cretaceous hydrocarbon system in the study area.