Source rocks evaluation and thermal maturity evolution of the dhamar ali field, sab’atayn Basin, Yemen

The Upper Jurassic samples of Dhamar Ali field, NW Sabatayn Basin, western Yemen were used to determine the source rock characteristics and petroleum generative potentials. Organic-rich sediments within the Meem and Lam members (Madbi Formation) were analyzed using organic geochemistry. The obtained data show that the total organic carbon content (TOC) values for the Meem and Lam source rocks are between 0.2 and 1.68 wt% indicating fair to good source rocks. The bulk geochemical results showed Lam and Meem Members displaying generally Type III kerogen, which have the ability to generate mainly gas accumulations under thermal maturation level. The results of thermal maturation by vitrinite reflectance (VR) and Tmax shows that the analyzed Meem source rocks are generally plotted in the mature zone, while the results of Lam source rocks samples show that the source rocks is still immature zone and marginally mature zone. 1D basin modelling was performed to analyse the hydrocarbon generation and expulsion history of the study area. The burial/thermal history models shows regular trend pattern with no significant subsidence or uplift events in the Dhamar Ali field of NW Sab’atayn Basin. Meem source rock has been reached required level of thermal maturity while Lam unit did not enter the main oil generation phase due to shallower depth and insufficient temperature in the study area. Therefore, the Meem Member can be consider as generative potentials of prospective source rock horizons in Dhamar Ali field, NW Sabatayn Basin.