【摘要】 依据剖面露头样品的实验测试资料,通过Rock-Eval岩石评价、显微镜下观察、镜质体反射率、烃源岩可溶有机质特征、单体烃碳同位素等分析方法,对南羌塘盆地侏罗系烃源岩地球化学特征进行综合研究。研究结果表明:南羌塘盆地侏罗系烃源岩有机质丰度较低,总体上夏里组泥质烃源岩要好于布曲组和索瓦组碳酸盐岩烃源岩;烃源岩的有机质类型较好,主要为Ⅱ1型,并且反映出烃源岩形成于具一定盐度的较强还原环境,其有机质以海相低等水生生物为主;烃源岩的热演化程度总体较高,达到高成熟阶段。正构烷烃单体烃碳同位素分析表明,侏罗系各组烃源岩之间在母质输入上可能存在较大差异,该地区白云岩油苗与夏里组泥质烃源岩有很强亲缘关系。更多还原

【Abstract】 According to the surface samples and test data,the authors use analytic methods of Rock-Eval,microscopic observation,vitrinite reflectance,biomarkers comparatively and carbon isotope compositions of individual n-alkanes to analyse the organic geochemical characters of the Jurassic source rocks in South Qiangtang basin.The result reveals that the organic matter abundance of source rocks is lower in Jurassic,the type of organic matter is mainly Ⅱ1,and the overall high degree of thermal evolution to achieve high mature stage.The organic source material is mainly low-grade hydrobios,the hydrocarbon source rocks form in a certain strong salinity reduction environment.Alkane isotope analysis show that it may be quite different in the parent material for the Jurassic source rocks in each formation.Dolomite oil seepage has a strong affinity with the mudstone source rocks of Xiali Formation in the study area.更多还原