Organic Geochemical Evaluation of Madbi Source Rock, Al-Jawf Basin, NE Central Yemen

Abstract

Organic geochemical evaluation of the Madbi Formation as the main source rock of the Al-Jawf Basin, NE Central Yemen was the main objective of this study. The organic geochemical methods used in the study include: rock-eval pyrolysis, total organic carbon, and optical measurements as the vitrinite reflectance and thermal alteration index. In this study, 67 well core and side-well core samples of the H-1 and K-1 exploratory wells of the Al-Jawf Basin were analyzed to calculate the several organic geochemical and optical parameters. The obtained results show the presence of strong source rock probabilities within the Madbi Formation in this basin. The results are classified into three categories: poor, fair, and good source rocks, with a mixed marine Kerogen type II/III and continental Kerogen type III. The maturation of source rocks was affected by heating and re-cycling of heat events during the Cretaceous and Tertiary periods. This interpretation is strongly related to the breakup of the southern Gondwanaland and the opening of the Red Sea and Gulf of Aden. Based on the evaluation of the source rocks, the shale, calcareous shale, and claystones of the Madbi Formation are considered the main source rocks in this basin. According to the present study, the hydrocarbon potential ity is good to fair grade in the Al-Jawf Basin.