不同沉积环境原油的芳烃组成特征及其地质地球化学意义

Features of Aromatic Composition in Crude under Different Sedimentary Environments and Its Geochemical Meanings

不同沉积环境下形成的原油其芳烃组成是有差异的。对塔中地区、柴达木盆地、吐哈盆地以及冀中坳陷4个不同沉积盆地的10个原油样品进行全油GC/MS分析。研究结果表明,海相原油未检测出卡达烯和惹烯,其硫芴含量在"三芴系列"中占优势;咸水湖相原油也是以硫芴占优势,并且含有丰富的三芳甾烷系列化合物;沼泽相原油"三芴系列"中氧芴占优势,一系列稠环芳烃化合物的检出揭示了较强的陆源高等植物输入,同时检出了苯并藿烷系列化合物;淡水湖相原油则以芴占优势。

Aromatic compositions of crude oil formed under different sedimentary environments were different.All oil GC/MS analysis was conducted on 10 oil samples from 4 different sedimentary basins of Tazhong Region, Qaidam Basin, Tuha Basin and Jidong Depression.Study results show that cadalene and retene were found out in marine oil, dibenzothiophene is obvious in 'three-fluorene system' , the dibenzothiophene is also prevailing in oil from salt-water lake facies, and it contains the compound of triaromatic steroid series, oxygen-fluorene is prevailing in 'three-fluorene system' of swamp facies oil, a series of condensed aromatic compounds are checked out, it displays a strong imput of higher terrigenous plants, and also the compounds of beneohopane series are checked out, while fluorine is prevailing in the oil from fresh water facies.