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通过柴达木盆地周缘地区上古生界暗色泥岩、碳酸盐岩、煤及碳质泥岩的有机地球化学的测试分析,研究结果表明,石炭系烃源岩主要以暗色泥岩为主,炭质泥岩和煤可能具有生烃能力。下石炭统暗色泥岩有机碳含量一般达到了差到中等,而上石炭统暗色泥岩有机碳含量达到好或者很好;上、下石炭统的暗色灰岩有机碳含量均比较低,一般仅为非到差等烃源岩。有机碳评价较好的泥岩主要发育在潮坪、泻湖、沼泽相沉积相类型中;剖面上评价较好的层位为怀头他拉组的中部和克鲁克组及其扎布萨尕秀组的下段,评价结果已经达到好到很好等级。样品中的有机质类型均以Ⅲ型和Ⅱ2型为主。除都兰、格尔木地区有机质成熟度过高、处于过成熟的生干气阶段外,其他地区有机质成熟度中等,正处于生烃、排烃高峰期,具有良好的油气勘探前景。
Through the organic geochemical analysis of the Upper Paleozoic dark mudstone, carbonate rock, coal and carbonaceous mudstone in the peripheral area of the Qaidam basin, the results show that the Carboniferous source rock is dominated by dark mudstone, while the carbonaceous mudstone Coal may have hydrocarbon generation capacity. The organic carbon content of the Lower Carboniferous dark mudstone generally reaches poor to moderate, but the organic carbon content of the Upper Carboniferous dark mudstone is good or very good. The organic carbon content of the dark limestone in the Upper Carboniferous and the Lower Carboniferous is relatively low, To poor source rocks. Mudstone with good organic carbon evaluation is mainly developed in the sedimentary facies of tidal flat, lagoon and swamp facies. The favorable layers in the profile are the middle part of the Huntou Tala Formation and the Crooks Formation and its Zhabsa Gallega The lower part of the group, the evaluation results have reached good to very good level. The types of organic matter in the samples are mainly Type III and Type II2. In addition to the mature organic matter in the Dulan and Golmud regions, which is in the stage of over-mature raw dry gas, the maturity of organic matter in other regions is moderate and is at the peak of hydrocarbon generation and hydrocarbon expulsion with good prospects for oil and gas exploration.