塔里木盆地北部寒武—奥陶系海相烃源岩重新认识

根据对塔北地区591块泥质源岩613块碳酸盐岩热解资料的统计分析表明，本区中上奥陶统泥质岩除柯坪地区相对较好外，其余地区普遍属一非生油岩，不可能对已发现的海相油气有实质性的贡献。而寒武系无论是碳酸盐岩还是泥岩，其有机质丰度均高于奥陶系，尤其是碳酸盐岩烃源岩厚度也较大，因而是塔里木盆地一套十分重要的海相油气源岩，现今为一套优质气源岩。其次是中上奥陶统台缘斜坡灰泥丘有机相泥灰岩，具有有机质丰度较高、成熟度适中及具有一定厚度分布的特点，是本区海相油气另一大套重要源岩。另外，平面上，本区寒武一奥陶系泥岩的有机质丰度表现为东西两端相对较高，可达到中等一很好生油岩标准，而草湖、轮南、英买力以及孔雀河斜坡与满加尔凹陷奥陶系泥岩基本上均属差一非生油岩。碳酸盐岩烃源岩则以库尔勒鼻隆及塔东（含库鲁克塔格）地区为最后，其次是哈拉哈塘凹陷。

Evoluation on the Cambrian-Ordovician Marine Source Rocks from the North Tarim Basin

Based on the statistical analyses of the Cambrian-Ordovician source rocks from the North Tarim Uplift and its neighboring areas,it can be concluded that the Cambrian and lower Ordovician carbonate rocks should be the main source rocks of this areas comparatively,the Cambrian sourece rocks are totally better than the Ordovician because their contents of organic matters are higher than the Ordovician on average.Therefore the Cambrian mudstones and carbonate rocks are the most important source rocks.On the contrary,most of the mid upper Ordovician mudstones are bad or non source rocks in the study area except some outcrops.Overall,the abundance of organic matters of the Cambrian Ordvician mudstones is higher in the east and west ends than in the other areas,where the mudstones can be regarded as intermediate to excellent source rocks.Nevertheless,the Ordovivian mudstones in the Caohu,Lunnan,Yingmaili and Manjiaer regions are generally bad or non source rocks.Carbonate source rocks are also good in the east regions including Kuerle and Kuluketage,and those in Halahatang depression are the secondary.