西湖凹陷平北地区平湖组原油地球化学特征  

Geochemical Characteristics of Pinghu Crude Oils in Pingbei Area of Xihu Sag

作　　者：殷世艳[1,2] 叶加仁[2] 雷闯[3] 单超[2] 田杨[2] 刘方圆[2] 

机构地区：[1]河北联合大学矿业工程学院,河北唐山063009 [2]中国地质大学构造与油气资源教育部重点实验室,武汉430074 [3]中国石油冀东油田分公司勘探开发研究院,河北唐山063004

出　　处：《新疆石油地质》2014年第5期542-546,569,共6页Xinjiang Petroleum Geology

基　　金：国家科技重大专项(2011ZX05023-001);河北省自然科学基金(D2013209045)

摘　　要：西湖凹陷平北地区平湖组原油C7轻烃化合物中甲基环己烷含量较高,二甲基环戊烷和正庚烷含量较低,石蜡指数为3～13,正构烷烃碳数分布范围较宽,且不具奇偶优势,多数样品Pr/Ph分布在3.6～8.2;甾烷化合物主要由规则甾烷构成,C29规则甾烷占绝对优势,且异构化程度相对较高;藿烷含量相对较高,藿烷与规则甾烷比值为1.5～6.7,伽马蜡烷含量较低,同时可以检测出丰富的二萜烷;芳烃组分中检测到惹烯,甲基菲指数为0.71～1.42,三芴系列化合物以芴含量最高.综合分析认为,平湖组原油母质来源以陆生有机质为主,多数形成于氧化-强氧化的湖沼相沉积环境,少数形成于弱氧化的半深湖相沉积环境,现今主要处于成熟-高成熟演化阶段.Based on the analysis of the light hydrocarbons,saturated hydrocarbons and aromatic hydrocarbons from crude oil in Pingbei area of Xihu sag,the C7 light hydrocarbon compound of the Pinghu crude oil are characterized by （1） high methylcyclohexane content,low dimethylcyclopentane and pentane content,and paraffin wax index and heptane value ranging from 3 to 13 and 10％～18％,respectively; （2） wide distribution of carbon number of the n-alkanes without odd-even predominance,the Pr/Ph ratios in most samples distributing between 3.6 and 8.2; （3） steranes mainly consisted of regular sterane,with highest C29 sterane,and relatively high degree of isomerization; （4） relatively high hopane content,the hopane/sterane ratio of 1.5～6.7,low gammacerane content and abundant diterpene; and （5） some Reteneis detected from the aromatic components,the methylphenanthrene index being between 0.71 and 1.42,the highest fluorenehas content among the three series of fluorenecompounds.A comprehensive analysis shows that the oil-forming matrix in Pinghu formation is dominated by terrestrial organic matter,most formed in the oxidation-strong oxidation limnetic facies sedimentary environment,with minority parent material formed in weak oxidizing semi-deep lake facies environment,and the kerogen is mainly in stage of mature to high-mature evolution.

关 键 词：东海大陆架盆地 西湖凹陷 平北地区 平湖组 生物标志化合物 轻烃化合物 芳烃化合物 

分 类 号：TE111.113[石油与天然气工程—油气勘探]