【摘要】 分析研究了扎鲁特盆地晚二叠世林西组烃源岩芳烃馏分中甲基菲异构体的相对组成及其变化。研究结果表明林西组中上部烃源岩中甲基菲分布模式为9-MP>2-MP>1-MP>3-MP;林西组下部烃源岩其甲基菲分布模式为2-MP≥9-MP>3-MP>1-MP。3-MP、2-MP的相对丰度随着埋深增加而增高;而9-MP、1-MP则相反。MPI1与Ro具有良好的正相关性。Rc分布在1.69%~2.03%,平均值为1.90%;Ro分布在1.35%~1.80%,平均值为1.57%。根据Ro与Rc的相关关系判断林西组烃源岩处于高成熟演化阶段,结合有机质类型判断烃源岩以生气为主。更多还原

【Abstract】 The distribution features of methyl phenanthrene from the hydrocarbon source rocks of Late Permian Linxi Formation in Zhalute Basin were analyzed. The results show that there are three distribution patterns of methyl phenanthrene. The distribution pattern of methyl phenanthrene in Middle-Upper Linxi Formation is the first one that the relation of relative abundance is 9-MP > 2-MP > 1-MP > 3-MP. The distribution pattern of methyl phenanthrene in Lower Linxi Formation is the second one and the third one that the relations of relative abundance are 2-MP ≈ 9-MP > 3-MP > 1-MP,2-MP > 9-MP > 3-MP > 1-MP,respectively. It is found that there is a good positive correlation between the burial depth and the relative abundance of 3-MP and 2-MP. However,there is a good negative correlation between the burial depth and the relative abundance of 9-MP and 1-MP. Similarly,methyl phenanthrene indexes( MPI1,MPI2) have good negative correlation with the vitrinite reflectance. Rcranges from1. 69 to 2. 03 percent with an average value of about 1. 90 percent and Roranges from 1. 35 to 1. 80 percent with an average value of about 1. 57 percent. According to the relationships between the vitrinite reflectance and Rc,the source rocks turn into high mature stage. It is concluded that the hydrocarbon source rocks of Linxi Formation in Zhalute Basin have good gas generation potential.更多还原