Study On The Oil Source And Accumulation Conditions Of Key Oil And Gas Reservoirs Around Zhaquan

Zahaquan depression with rich oil and gas resources, which has a huge potential of exploration, has sedimentaried Cenozoic layer. The thesis use the theory of petroleum system and bases on the subject of petroleum geology,hydrocarbon geochemical,structural geology and reservoir petrology, and conbined with entire hydrocarbon geochemical methods and the theory of oil-gas "partition capturing", by means of comparing with oil in zahaquan periphery and source rock in Zahaquan depression, and find out the different stratigraphic positions of oil sources for different reservoirs, and confirm the acquisition phases of oil and gas. Apply the method of analysis of reservoir fluid inclusion, microscopic fluorescent light and reservoir extraction.etc to determine the reservoir-forming time and stage of Kunbei,Yuejin and Wunan area. After analysis of the oil's distribution, migratory and conservation condition, on the foundation of tectonic and source rock evolution history, find out the main controlling factors and establish reservoir-forming modes.The research of source rocks show that, the hydrocarbon source rock of E32,with high organic matter abundance and well organic matter type, in the Zahaquan depression is the main oil source for Zahaquan depression periphery, which has aready gotten the stage of maturity. After studying of sedimentary formation concludes that there are high qualities reservoirs and cap rocks in depression periphery. The research of tectoni show that there are many of trap types, includes base uplift anticlinal trap, fault trap, formation unconformity trap and lithologic trap. And there are abundant of oil-gas migration pathway systems, include frature, unconformity and sand body. So the reservoir forming conditions are dominance.Wunan, yuejin and kunbei area had captured the low maturity oil of the hydrocarbon source rocks of E32, the reservoir forming time in the between of middle N1 and middle N21.in yuejin area,the low maturity oil migrate from E32 to N1 or N21 by near depression fault and then migrate to high positions of structures through the sand body, number ? fault made the depth of two sides bury layer different, reservoir in hanging side was suffered of biodegradation and generated thickened oil or bitumen, oil in footwall be saved without damage. The low maturity oil migrate to Wunan N1 and N21 reservoir by the number of south 20 fault and sand body, for its deep bury, the oil was in good keep. Kunbei area has many of trap types, which formation time are early and has rich migration systems between source rock and reservoir, and has captured two stages oil. In middle of N1,the low maturity oil magrate to Kunbei by fault and unconformity, and then the layer upraise making the reservoir damage and forming bitumen after light component disapper. Later N23 maturity oil mainly migrate to shallow layer by Kunbei fault on the influence of dip angle, and then crosswise migrate to secondary fault through unconformity. For two stages oil aggregation, the scale of Kunbei reservoir is larger than Wunan and Yuejin's.