In order to find out the geological characteristics and enrichment law of continental shale oil and gas, the geological characteristics and enrichment law of Lianggaoshan Formation shale oil and gas reservoir in Fuling area were studied by means of whole rock mineral X-ray diffraction, organic geochemistry, argon ion polishing scanning electron microscope, helium porosity, field gas content test and seismic pressure coefficient prediction. It is pointed out that Lianggaoshan Formation shale has the characteristics of high mud to ground ratio, high GR, high TOC and high gas content. It is proposed that the enrichment and high yield of continental shale oil and gas in Fuling area are mainly controlled by four factors: (1) Semi-deep lacustrine shale distributed in large area is the basis of hydrocarbon generation and reservoir control of shale oil and gas; (2) The appropriate degree of evolution controls the enrichment and accumulation of continental shale oil and gas; (3) Good preservation conditions are the key to the enrichment and accumulation of shale oil and gas; (4) The development of micro fractures with different scales is conducive to the high production of continental shale oil and gas. Among the influencing factors, the preservation conditions and the development of microfractures have the greatest impact on enrichment and high yield.
Keywords:Fuling area
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Shale oil and gas
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Continental facies
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Enrichment rule
WANG Wei, SHI Wenbin, FU Xiaoping, XIE Jiatong, NI Kai. Oil and gas enrichment regularity of continental shale of Lianggaoshan Formation of Middle Jurassic in Fuling area, Sichuan Basin. Natural Gas Geoscience[J], 2022, 33(5): 764-774 doi:10.11764/j.issn.1672-1926.2021.10.010
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