After JY1 well achieved a breakthrough in marine shale gas exploration in South China, the understanding of the law of “binary enrichment” of marine shale gas in complex structural areas is proposed through anatomy and exploration. Through continuous and in- depth research on the key scientific and technological problems in the “13th five year plan” period, it is further clarified that the high- quality shale of deep- water continental shelf facies is the basis of “hydrocarbon generation and storage control” of shale gas, and the preservation condition is the key profound connotation of shale gas enrichment and high yield. The set of shale planktonic algae and planktonic siliceous organisms coexisted and flourished. The diagenetic porosity of siliceous biological bone debris is conducive to the in- situ retention of hydrocarbons generated by algae and the development and preservation of a large number of organic pores formed by late pyrolysis. The sealing conditions of roof and floor and the strength of later tectonic movement are the key factors for shale gas enrichment and preservation. It reveals the enrichment and preservation mechanism of marine shale gas “integration of source and reservoir, early retention, in- situ enrichment and late transformation”, and defines the target and direction of marine shale gas exploration in complex structural areas. Deep, atmospheric and continental shale gas will be an important replacement field for shale gas exploration and development in and around Sichuan Basin. During the “14th five year plan” period, shale gas exploration in Sichuan Basin is expected to develop more rapidly.