Abstract:Significant breakthroughs have lately been made in oil and gas exploration in the Shulu buried- hill belt, showing great potential for oil and gas exploration in the southern Jizhong depression. However, the main controlling factors and models of hydrocarbon accumulation in the buried- hill belt have not been systematically studied, which limits the further oil and gas exploration in the area. In this paper, the hydrocarbon accumulation conditions of different types of buried- hill reservoirs, the main controlling factors and models of hydrocarbon accumulation in the Shulu buried- hill belt, Jizhong depression have been systematically analyzed based on numerous drilling, logging, geochemical data, sample testing and analysis, and basin modeling method. The results show that the main controlling factors of hydrocarbon accumulation in the Shulu buried- hill belt are source kitchen, migration system and preservation condition, among which the source kitchen controls the maturity and distribution of hydrocarbons to a certain extent, migration system controls the migration and accumulation, and the size of the reservoir, while the preservation conditions control the property and enrichment of oil and gas. The reservoirs in the paleo- uplifts experienced two stages of hydrocarbon charge events (late Es2 to Ed and Nm to present), characterized by near- source fault transport- faulted anticline accumulation system. The reservoirs in the slope area only experienced a single stage of low maturity- normal oil charge event from Nm to present, typical of far- source unconformable transport- reverse fault block accumulation system. The research results may provide scientific basis for understanding hydrocarbon accumulation mechanism and oil and gas exploration in buried- hill belts of the area.