Construction of Comprehensive Evaluation Criteria for Shale Oil Sweet Spot of Liushagang Formation in Weixi'nan Sag

China's continental shale oil resources have huge potential and are an important strategic replacement resource for conventional oil and gas in China. This study focuses on the construction of the shale oil reservoir evaluation system of the Liushagang formation in the Weixi'nan sag. In view of the characteristics of the shale oil reservoir space types of the Liushagang formation in the Weixi'nan sag being diversified (matrix type, laminar type and interlayer type) and the significant heterogeneity of the reservoir, starting from the characteristics and comprehensive evaluation investigation of typical domestic shale oil. The similarities and differences between the shale oil in the Weixi'nan sag and typical domestic shale oil are compared. By exploring the tripartiality characteristics among the main evaluation parameters, the threshold boundaries of the evaluation parameters were reasonably determined, and a sweet spot comprehensive evaluation standard for different types of shale oil was constructed. Based on the constructed standards, the connection evaluation and comparison of five wells in the study area are conducted. The results showed that the type I comprehensive sweet spot section is mainly concentrated in the matrix type shale oil reservoir, and the validity of the comprehensive evaluation is verified based on the gas measurement and logging data. The research results will provide quantitative decision-making reference basis for the selection of shale oil development strata in Weixi'nan sag, and offer theoretical references for the improvement of the classification and grading evaluation standards of continental shale oil in China.