中文摘要：

应用有机岩石学和分子地球化学的手段和方法，对鄂尔多斯盆地西南缘三叠系延长组长7段暗色泥岩和长8油层组原油，进行地球化学精细定量分析，研究了长7段暗色泥岩地质地球化学特征，评价了西南缘三叠系延长组长7烃源岩生烃潜力，并对长8油层组原油展开精细油源对比分析．结果表明：鄂尔多斯盆地西南缘三叠系延长组长7段暗色泥岩有机质丰度高、类型好、成熟度高，与盆地本部长7优质烃源岩具相近似的电性、岩性和地球化学特征，为一套优质的烃源岩．长8油层组原油在母源性质、沉积环境、成熟度等方面与长7段烃源岩有相近似的特征，二者具有较好的亲缘关系，长8原油来自长7段烃源岩．

英文摘要：

Based on the methods of organic petrology and GC-MS, Triassic Chang 7 mudstone and Chang 8 crude oil were collected from the southwestern margin of the Ordos basin for a geochemical fine quantitative analysis. The geochemical characteristics of the hydrocarbon source and the hydrocarbon generating potential were discussed. The results showed that Chang 7 mudstone is still a major source rock in the study area with a high organic matter abundance, good types and characteristics of high maturity. At the same time, the geochemical features of the Chang 8 crude oils were investigated. Chang 8 crude oil and Chang 7 source showed similar characteristics in the aspects of resource properties, sedimentary environment and maturity. Therefore, Chang 8 crude oil mainly derived from the source rocks of the seventh members of the Yanchang formation in the southwestern mar~in of the Ordos basin.