摘要
依奇克里克油田位于库车坳陷东部阳霞凹陷的北部。通过对依南5井不同深度储层所产原油地球化学特征的系统分析发现,浅层原油的轻烃几乎不含苯系芳烃,其三环萜烷系列以C23为主峰,C24四环萜烷含量低,伽马蜡烷含量较高,甾烷系列中C27和C28甾烷含量高,重排甾烷含量较低,显示咸水环境海相原油的特征。鉴于该原油中同时检测出了25-降藿烷系列,表明该原油是生物降解油与正常原油的混合油。而深部储层所产原油的轻烃中苯系芳烃丰富,三环萜烷以C19为主峰,C24四环萜烷含量极为丰富,伽马蜡烷含量极低,甾烷系列中C29甾烷占绝对优势,显示淡水湖沼相原油的特征。结合塔里木盆地不同成因类型原油的地球化学特征,推测依南5井不同深度所产原油存在这一差异的原因是浅层原油属于早期生物降解海相原油与晚期侏罗系湖沼相原油的混源油,而深部原油属于侏罗系烃源岩单一来源的原油。
The geochemical characteristics of crude oils from YN5 well in Yiqikelike Oilfield located at the northern Yangxia Sag of East Kuqa Depression,was analyzed and studied.The results show that in the light hydrocarbon of the crude oils from shallow reservoir,benzene series aromatics is almost absent,C23 is a maximum peak in tricyclic terpane series and C24 tetracyclic terpane is very low,the relative abundance of gammacerae is higher.In sterane series,their relative abundance is C27R<C28R<C29R,and diasterane is very lower,indicating that it has the characteristics of marine oils in Tarim Basin.In addition,25-norhopane series,an indicator of severe biodegradation of crude oil,are identified in the crude oil.As for the crude oils from deeper reservoir,in its light hydrocarbon,benzene aromatic compounds are very abundant,C19 is a maximum peak in tricyclic terpane series and C24 tetracyclic terpane is very abundant,gammacerae isalmost absent.In its sterane series,C29 sterane is most abundant,and diasterane is relatively higher,indicating that it is characteristic of coal measure source rocks in Kuqa Depression.Therefore,based on their geochemical characteristics,the crude oil form shallow reservoirs is a mixed oil between the biodegraded marine oil and the oil derived from Jurassic coal measures,and the crude oils from deeper reservoir is derived from Jurassic coal measures.
出处
《石油天然气学报》
CAS
CSCD
北大核心
2009年第6期25-31,共7页
Journal of Oil and Gas Technology
基金
国家"十五"重点科技攻关项目(2004BA616A02-04-01-01)
关键词
原油
生物标志物
轻烃
库车坳陷
依奇克里克油田
crude oils
biomarker
light hydrocarbon
Kuqa Depression
Yiqikelike Oilfield
