盐城凹陷阜三段原油地球化学特征及油源对比  

Geochemical characteristics of crude oil and oil source correlation of the third member of Funing Formation in Yancheng Sag

作　　者：宋言 刘世丽[3] 高先志[1,2] 李鹤永[3] 唐远涛 薛锴 王红梅 王永辉 SONG Yan;LIU Shili;GAO Xianzhi;LI Heyong;TANG Yuantao;XUE Kai;WANG Hongmei;WANG Yonghui(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;Exploration and Development Research Institute of Jiangsu Oilfield Company,SINOPEC,Yangzhou 225009,China)

机构地区：[1]油气资源与探测国家重点实验室中国石油大学(北京),北京102249 [2]中国石油大学(北京)地球科学学院,北京102249 [3]中国石化江苏油田分公司勘探开发研究院,江苏扬州225009

出　　处：《复杂油气藏》2023年第1期26-34,共9页Complex Hydrocarbon Reservoirs

基　　金：中国石化江苏油田分公司科技项目“盐城凹陷阜宁组油藏成藏主控因素与勘探潜力研究”(JS21002);中国石化科技部项目“苏北盆地陆相页岩油富集条件与勘探评价研究”(P21113)。

摘　　要：盐城凹陷阜三段常规油藏的发现证实了盐城凹陷仍具有较大的勘探潜力,但受勘探程度的影响,缺乏系统研究,存在阜三段原油成因与阜二段烃源岩主要供烃亚段尚不明确的问题。通过分子地球化学分析,结合实际地质条件,对阜三段原油地球化学特征及来源开展研究。研究结果表明:阜三段原油为低熟稠油,母质来源为混合来源,形成于半咸化—咸化、还原—强还原环境,是生油早期阶段的产物;依据生标物特征可将阜二段烃源岩分为3类,E_(1)f_(2)^(2)亚段烃源岩成熟度低,形成于低咸度—还原环境,具有低孕(升)甾烷/规则甾烷、低三环萜/五环萜的特征。E_(1)f_(2)^(3)、E_(1)f_(2)^(4)、E_(1)f_(2)^(5)亚段烃源岩成熟度低,形成于高咸度—强还原环境,具有低孕(升)甾烷/规则甾烷、高三环萜/五环萜比值的特征。E_(1)f_(2)^(6)亚段烃源岩成熟度偏高,形成于较高咸度—还原环境,具有高孕(升)甾烷/规则甾烷,低三环萜/五环萜比值的特征;阜三段原油可分为2类原油,以Ⅱ类原油为主。综合油源对比结果与实际地质条件认为,Ⅰ类原油主要来自E_(1)f_(2)^(2)亚段烃源岩。Ⅱ类原油主要来自E_(1)f_(2)^(3)、E_(1)f_(2)^(4)亚段烃源岩,E_(1)f_(2)^(3)、E_(1)f_(2)^(4)亚段烃源岩为阜三段原油的主要供烃亚段。The discovery of conventional oil reservoirs in the third member of the Funing Formation in Yancheng Sag confirms that the Yancheng Sag still has a large exploration potential.However,due to the extent of exploration,there is a lack of systematic research,and there is a problem that the genesis of crude oil in the third member of Funing Formation,and the main hydrocarbon supply submember of hydrocarbon source rock in the second member of Funing Formation are still unclear.Through molecular geochemical analysis,combined with the actual geological conditions,it was studied the geochemical characteristics and sources of crude oil in the third member of the Funing Formation.The results show that the crude oil in the third member of the Funing Formation is low maturity heavy oil with mixed parental source,which formed in the environment of semi-salty and salinization,reduction-strong reduction,and is a product of the early oil generation stage.According to the characteristics of biomarkers,the hydrocarbon source rocks of the second member of Funing Formation can be divided into three categories.The hydrocarbon source rocks of the E_(1)f_(2)^(2) sub-member are low maturity,and formed in a low-salt-reducing environment,with a low sterane/regular sterane ratio and low tricyclic terpene/pentacyclic terpene ratio.The hydrocarbon source rocks of E_(1)f_(2)^(3),E_(1)f_(2)^(4),and E_(1)f_(2)^(5) sub-member have low maturity and formed in a high salinity-strong reduction environment,with a low sterane/regular sterane ratio and high tricyclic terpene/pentacyclic terpene ratio.The hydrocarbon source rocks of the E_(1)f_(2)^(6) sub-member have a high maturity,and formed in a high salinity-reducing environment,and are characterized by a high sterane/regular sterane ratio and low tricyclic terpene/pentacyclic terpene ratio.The crude oil in the third member of the Funing Formation can be divided into two types,mainlyⅡtype crude oil.Based on the oil source correlation results and actual geological conditions,it is concluded that th

关 键 词：低熟油 地球化学 油源对比 阜三段 盐城凹陷 

分 类 号：TE122.1[石油与天然气工程—油气勘探]