沉积物中NSO杂环芳烃的分布特征及其地球化学意义

Characteristics of NSO's compounds in sediment and their geochemical significance

对金湖凹陷原油和烃源岩中分子骨架结构相似、分别含N、S、O的三类杂环芳烃——吡咯类、硫芴和氧芴系列的分布特征及其应用进行了初步探讨。烃源岩中这三类杂原子化合物的丰度一般高于原油,其在油、岩中的丰度差异按含N、O和S化合物的顺序依次降低,指示三类化合物吸附性依次降低;原油和烃源岩中三类杂原子化合物丰度具有较好的正相关性,并与芴系列具有良好的多项式关系,暗示三类杂原子化合物在原生和或后生作用与干酪根降解方式上可能有某些相似性与相关性;在未熟—低熟阶段,随着成熟度的增加,三类化合物的丰度逐渐增加,指示成熟度对其有一定的控制作用。NSO化合物在油气运移、成熟度评价和指相等方面具有重要意义。

Characteristics of three kinds of NSOs compounds with similar molecula r structure in oils and rocks of Jinhu sag,Subei basin are analyzed,which are pyrrolic nitrogen compounds,dibenzofurans and dibenzothiop henes.It is found that the source rocks are r elatively rich in the three kinds of h eteroatomic compounds than the oils,especially the pyrrolic nitrogen co mpounds,with the dibenzothiophenes least enriched among the three of th em.It is inferred that polarity of the three c ompounds decrease according to the o rder of pyrrolic nitrogen compounds,dibenzofurans and dibenzothiophen es.The abundance of the three kinds o f the compounds displays good positive correlation each other,suggesting possibly similar genetic mechanism.There are also good correlation between fluorene and the three compounds respectively,suggesting probably gen etic correlation between them.The f actors having control on the heteroatomic c ompounds are probably similar to hyd rocarbon fraction.It is observed th at the abundance of the three compounds in t he oils and rocks all increases with t he increasing maturity,and it seems that maturity also have an effect on the re lative distribution of dibenzothio phenes.There are apparently migration effect of the pyrrolic nitrogen compounds i n the oils and the migration effect of dibenzofurans and dibenzothiophen es could also be observed from their absolute abundance variety.NSOs compounds may have significance in several asp ects such as oil migration effect,oil and source rock correlation,maturity e valuation,paleoenvironment etc.