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早、中侏罗世含煤地层遍布中亚,中国西北地区也很发育,在准噶尔盆地南部、塔里木盆地北部及吐鲁番盆地的厚度分别超过2500m,2300m和1500m。沿横穿盆地边缘这些地层露头带,13个断面的分析研究表明,全为非海相曲流河沉积,局部发育有辫状河流相和湖泊三角洲相。中国的地下数据表明,区域性侏罗系湖泊相存在于沉积倾斜的下方,与全球性早、中侏罗世季风降水量的环流模拟预测相一致。取自准噶尔、塔里木、吐鲁番盆地的4个油样地化对比,有力地说明了侏罗系煤质沉积物及其下倾方向的同期湖泊沉积物是油源岩。油样的和被认为是侏罗系源岩抽提物的甾烷、藿烷分布相似,且易区别于其他源岩层的甾烷、藿烷分布。对比参数还包括:高姥/植比;三环萜烷丰度低或缺失,但只要存在则分布相似;缺失表征二叠系和奥陶系源岩及其原油的伽马蜡烷(有一例外)和胡萝卜烷。侏罗系样品的热解—气相色谱分析表明,它们具备了生成液态烃的潜力,C_(15+)烃很可能是从侏罗系源岩排出的,尽管传统观点认为沥青煤不具有排出长链烃的能力。
The Middle and Early Jurassic coal-bearing strata are all over Central Asia and are also well developed in the northwestern China. The thicknesses in the southern Junggar Basin, the northern Tarim Basin and the Turpan Basin exceed 2500m, 2300m and 1500m respectively. The analysis of 13 sections along these stratigraphic outcrops crossing the margin of the basin shows that all are non-marine meandering rivers, with locally developed braided river facies and lacustrine delta facies. Underground data from China indicate that the regional Jurassic lacustrine facies exists below the depositional slope and is consistent with the global circulation and monsoon prediction of monsoon and mid-Jurassic precipitation. The comparison of four oil samples taken from Junggar, Tarim and Turpan basins strongly suggests that the sediments of Jurassic coal deposits and the sediments of the same dip direction are source rocks. Oil samples and is considered to be the strontium of the Jurassic source rock extract, hopane distribution similar to, and easy to distinguish from other source rock sterane, hopane distribution. The comparative parameters also include: high basking / plant ratio; tricyclic terpanes with low or absent abundance but similar distributions as long as they exist; absence of gamma-alkanes characterizing Permian and Ordovician source rocks and their crude oils (with one exception) ) And carrot alkane. Pyrolysis gas chromatography analysis of Jurassic samples showed that they possessed the potential to generate liquid hydrocarbons. It is possible that C 15+ hydrocarbons are expelled from Jurassic source rocks, although it is conventional wisdom that bituminous coal does not have the ability to drain Chain hydrocarbon capacity.