通过对吐哈盆地煤系地层中下侏罗统煤岩、炭质泥岩、原油饱和烃组分的有机组分分析,获得以下认识:具有共同的特征生物标志化合物:γ-羽扇烷、异降松香烷、C24-四环二萜烷、高丰度C29甾烷,表明它们具有相同的高等植物母质来源。较高Pr/Ph比值、以及γ-蜡烷相对丰度很低等指示环境的参数具有一致性,说明它们的早期沉积环境相同,都是水质偏淡的弱氧化-弱还原环境。甾烷异构化参数C29-ββ/(ββ+αα)在研究的低演化煤岩及炭质泥岩(Ro:0.47~0.53)中显示明显的高比值(0.294~0.489),显示岩样在成岩过程中曾遭受过比较强烈的微生物作用,因此,煤岩早期的微生物作用可能是煤系地层早期生烃的动因。
Saturated hydrocarbon of coal, carbonaceous mudstone and oils from the Lower Jurassic coal measures in the Turpan basin have been analyzed by GC/MS in this paper, and biomarker characteristics and coal thermal maturity analyzed to draw the following conclusions:There are many similar biomarker characteristics between oil from middlelower Jurassic of Turpan Basin and coal and carbonaceous mudstone in the same strata. They all contain specific γ-lu- pane, I-norbietane,C24-tetracyclic and high content of C29-steranes. These characteristics suggest that they should have similar matter source of the organic matter are derived from matter with abundant high plants. Meanwhile, biomarkers, often used to indicate depositional environments, is characterized by high Pr/Ph ratio, little or no gammaccrane and high abundance dibenzofurans, such biomarker distributions are indicative of suboxic and freshwater environment. Although coal and carbonaceous mudstone remain in lower thermal maturity (Ro = 0.47 - 0.53 ) , but C29- ββ/αα + ββ)sterane ratio (0. 294-0. 489) and bezohopane are detected in this study. Because these fearture are related to bacterial activity, so bacterial degradation of organic matter may play an important role in coal-derived oil.