HYDROCARBON GENERATION EVALUATION AND FAVORABLE AREA PREDICTION OF CARBONIFEROUS-PERMIAN SOURCE ROCKS IN HUANGHUA DEPRESSION BOHAI BAY BASIN

In this study, the comprehensive evaluation of Shanxi and Taiyuan formation source rocks is carried out from three aspects of organic matter abundance, organic matter type and organic matter maturity. In terms of organic matter, the dark mudstone and carbonaceous mudstone of the two formations are evaluated as medium-good source rock and poor-medium source rock respectively with TOC content as the division index. The organic matter abundance of coal seam is poor according to S1+S2 index of pyrolysis hydrocarbon generation potential. It is defined by the quartering of kerogen types. combined with the triangles and composition characteristics of soluble organic matter and IH-Tmax diagram of rock pyrolysis, it can be seen that the organic matter types of Shanxi formation and Taiyuan formation are mainly II2-III type. The vitrinite reflectance is used to evaluate the maturity of organic matter in the source rocks of the two formations. The results show that the thermal evolution degree of the source rocks is high and they are in the mature stage. Based on the above conclusions of source rock evaluation, combined with the tectonic setting of hydrocarbon generation area development, thickness of high-quality source rock, reservoir physical properties and other factors, the contour map of hydrocarbon generation intensity is drawn, and the distribution of favorable hydrocarbon generation areas is precisely depicted.