We analyzed the hydrocarbon enrichment conditions in shale in the West Liaohe Sag of Bohai Bay Ba⁃sin, and discussed the distribution features and pattern of shale oil and gas in continental rift basins, based on the tests of a large number of shale samples. The shale in the third and fourth members of Paleogene Shahejie Formation in the West Liaohe Sag has a large total thickness, wide distribution, good continuity, high TOC con⁃tent (average 2.67%), and medium maturity (0.4%-1.5%). Organic matter is mainly sapropelic, and partially of humic type. The shale developed considerable pores, mostly intergranular and dissolution pores, and tectonic ( with some interlayer) fractures. Favorable physical properties of reservoirs and high hydrocarbon content made the study area a good place for shale oil and gas enrichment. Controlled by sedimentary facies, organic matter type and thermal maturity, the West Liaohe Sag mainly yields shale oil, and regionally shale gas. From the bot⁃tom of the fourth member to the upper part of the third member of the Shehejie Formation, we found shale oil and gas, shale oil, and shale gas in turn. In the basin center, we mainly found shale oil, while on the slope we found interbedded shale oil and gas.%在大量泥页岩样品化验测试的基础上，分析了渤海湾盆地辽河西部凹陷页岩油气富集的条件，探讨了陆相裂谷盆地页岩油气分布特征和分布模式。研究认为，西部凹陷古近系沙四段和沙三段泥页岩累计厚度大、连续性好，有机质以腐泥型为主，发育一定量的腐殖型；有机质丰度高，TOC平均2．67％，热成熟度中等，Ro值0．4％～1．5％；泥页岩孔隙和裂缝较发育，孔隙以粒间孔和溶蚀孔最为发育，裂缝以构造缝和页理缝为主；储集物性好，含油气量高，具备页岩油气富集的基本条件。受沉积相、有机质类型与热成熟度联合控制，西部凹陷以发育页岩油为主，同时局部地区发育页岩气，页岩油气在纵向上和横向上有规律分布。纵向上，沙四段底部到沙三段上部地层依次发育页岩油气—页岩油—页岩气；横向上，断陷沉积中心以页岩油发育为主，盆地斜坡区为页岩油气频繁互层区域。
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