姬塬地区延长组原油地球化学特征及油源分析  

Geochemistry and origin of crude oils of the Yanchang formation in Jiyuan area

作　　者：罗丽荣[1,2] 昝川莉[1,2] 吴凯[1,2] 李善鹏[1,2] 刘飞[1,2] 马军[1,2] 

机构地区：[1]中国石油长庆油田分公司勘探开发研究院,陕西西安710018 [2]低渗透油气田勘探开发国家工程实验室,陕西西安710018

出　　处：《石油化工应用》2013年第7期76-82,共7页Petrochemical Industry Application

基　　金：国家科技重大专项;项目编号:2011ZX05001-004

摘　　要：利用族组成、碳同位素、饱和烃气相色谱-质谱等方法,系统地分析了姬塬地区延长组原油与烃源岩的地球化学特征,并进行油源对比及成因分析。研究表明,原油的δ13CPDB值介于-32.79‰～-30.69‰,碳同位素组成偏轻,与盆地中生界各产层湖相油型油一致。甾烷中含一定的孕甾烷、升孕甾烷和重排甾烷,αβ和βα构型甾烷丰富,原生甾烷的"V"字型分布反映了湖相油型油的特征,原油多呈五环萜烷含量高,17α(H)-C30重排藿烷(C30*)相对丰度存在显著差异,伽马蜡烷含量低的特征。油油,油源对比显示,姬塬地区延长组的原油形成于弱还原和淡水,微咸水环境,主要来自于长7油层组烃源岩。The geochemical features, origin and genesis are studied systematically by using group composition, stable carbon isotope and saturated hydrocarbon analysis. The results show that oil is typical lacustrine-derived oil, with δ13CPDB value generally from -32.79 ‰～-30.69 ‰ . Sterane and terpane biomar kers of compounds in oil from the region and source rock from Ordos basin were systematically analyzed. The oil contains a certain amount of pregnane, homo-pregnane, rearranged sterane and enriches αβ and βα isomers,while ααα-20R sterane isomers display an asymmetric ＂V＂type distribution pattern. Its terpane distribution is characterized by high content of pentacyclic terpane, low content of gammacerane and there are significant differences in relative abundance of 17α （H）-diahopanes. The biomarker distributions of the oils show that they were formed under a weak reducing and fresh water environment. The results of oil-source rock correlation showed that the oil was mainly derived from Chang-7 source rock.

关 键 词：地球化学 油源 

分 类 号：TE122.2[石油与天然气工程—油气勘探]