Oil-generation characteristics of Mesozoic syn-rift Madbi source rock in the Masila Basin, Eastern Yemen: New insights from kerogen pyrolysis and bulk kinetic modelling

Organic-rich shale layer is present within the syn-rift Madbi Formation of the Masila Basin, representing excellent oil source rock. Twenty-five representative immature to very early-mature source rock samples from the Upper Jurassic Madbi shale sequences were investigated using bulk and quantitative pyrolysis techniques. The analytical program included TOC, pyrolysis (SRA), pyrolysis GC, bulk kinetics, and kerogen microscopy. The results were used to characterize the kerogen composition and type of petroleum generated during thermal maturation from Madbi source rock and to clarify the variability of the organic matter and their effect on the timing of petroleum generation. Pyrolysis data identified two major organic facies with different petroleum generation characteristics; Type II kerogen with HI values of >400 mg HC/g TOC; Type II/III facies with HI values