吐哈盆地煤成烃研究

RESEARCH ON COAL-DERIVED HYDROCARBON IN TURPAN-HAMI BASIN

根据原油生物标记化合物有关参数的聚类分析 ,将吐哈盆地原油分成源于侏罗纪煤系沼泽相 (包括煤为源岩 )的第一类原油 ,源于中、下侏罗统过渡相富藻碳质泥岩和富藻煤的第二类原油和源于上二叠统塔尔郎组湖相泥岩的第三类原油。根据原油中生物标记物的年代学特征 ,提出利用二萜烷指数将侏罗系的原油 (二萜烷指数 >0 8)与上二叠统的原油 (二萜烷指数 <0 5 )加以区别的方法。根据不同沉积相带原油和相应源岩饱和烃组分中17 降扁枝烷和 5a 雄甾烷以及芳烃中的三芳甾系列化合物进行了精细的油源对比 ,确定了本区三类原油的 17 降扁枝烷、5a 雄甾烷和三芳甾系列化合物的分布特征及沉积相序关系 ,进一步从油源对比的角度证明了本区存在源于中、下侏罗统的具有商业价值的煤成油。

The cluster analysis of biomarker paramaters of crude oil is carried out,and the crude oil from Turpan_Hami Basin is classified into three types,including first type of oil derived from swamp facies of Jurassic coal_series,second type of that derived from carbonaceous mudstone and coal with high content of algae in Middle and Lower Jurassic transitional facies,and third type of that derived from lacustrine mudstone of Upper Permian Taerlang formation (P 2t).In accordance with the chronological characteristics of biomarkers of crude oil,the authors propose that the Jurassic crude oil and Upper Permian crude oil can be identified by Diterpene index.According to biomarkers,such as 17_norphyllocladane and 5 α_androstane of saturates and triaromatic steroids of aromatic hydrocarbon in crude oil and source rocks of different sedimentary facies,the correlation elaborate oil_source rocks as well as the correlation between depositional system and distribution of above biomarkers in the three kinds of crude oils are established.Moreover,the correlation of oil_source rocks indicates that industrially exploitable coal_derived oil is reserved in Turpan_Hami Basin.