库车坳陷中生代海侵事件对有机质的影响

对库车河剖面三叠侏罗系重要生烃组段进行了有机质生物标志化合物及单体烃同位素研究,研究结果表明,海侵层位与非海侵层位在生物组成和生标特征等方面明显不同,海侵带来了不同的生物体,使有机质类型发生了改变。在生物标志化合物参数方面表现为Ｐｒ／Ｐｈ小于１,甾烷含量丰富,甾烷中Ｃ_２７化合物丰度与Ｃ_２９相当,三环萜烷有Ｃ_２１＜Ｃ_２３＞Ｃ_２４的分布特点,单体烃同位素表现出富集轻碳同位素的特点。中生代海侵事件对塔北隆起区及库车拗陷油气资源具有重要的意义。

Influence on Organic Matter Cauced by Mesozoic Transgressive Events in the Kuqa Depression, Tarim Basin

Biomarker of organic matter and isotopic composition of n alkanes in saturated hydrocarbon have been researched,and major samples are selected from Triassic and Jurassic important source rock in Kuqa section.From results we can see that characteristics of biomarker and biological composition in transgressive member are different from non transgressive member.With various organisms input, the types of organic matter have been changed in transgressive processes.Biomarker parameters of transgressive member have specific characteristics:Pr/Ph less than 1,higher abundance of steranes,abundance of C 27 are similar to C 29 stertane,tricyclic terpane with feature of C 21 C 24 and isotopic composition of n alkanes enriched 12 C. Mesozoic transgressive events have important significance on oil and gas resources of Tabie uplift area and Kuqa depression in Tarim basin.