Controlling factors of organic matter enrichment in continental shale: A case study of the Jurassic Da’anzhai member in the Sichuan Basin

The continental lake basin is a favorable accumulation area of shale oil and gas; however, the organic matter enrichment regularity in facies still controversial, which hinders exploration gas Sichuan Basin. In this study, relationship between sedimentary environment was analyzed by petrology inorganic geochemistry tests 153 samples. results show that different lithologic associations Da’anzhai member have contents matter. Among them, TOC content unit II (shale-limestone interbed) highest, mainly, type kerogen, followed III (shale clip shell limestone belts), kerogen. Geochemical indicators paleoenvironmental factors play leading roles periods member. Unit ? deposited an arid with less fresh water supply; therefore, cycle hampered. Due to effect salinity stratification, anoxic formed, beneficial preservation algae plankton basin, resulting formation 2 semi-humid semi-arid climate, its oxidizing environment. Precipitation river runoff increase input terrigenous debris higher plants form This study has guiding significance for cause prediction zones.