渤海湾盆地南堡凹陷油源断裂特征与油气差异富集模式  

Characteristics of oil-source faults and differential enrichment patterns of oil and gas in Nanpu Sag in Bohai Bay Basin

作　　者：刘华[1] 欧阳冠宇 刘晓[2] 刘景东[1] 陈蕾[2] 张芷晴 刘海青[2] LIU Hua;OUYANG Guanyu;LIU Xiao;LIU Jingdong;CHEN Lei;ZHANG Zhiqing;LIU Haiqing(School of Geosciences,China University of Petroleum(East China),Qingdao 266580,China;Explora-tion and Development Research Institute of PetroChina Jidong Oilfield Company,Tangshan 063004,China)

机构地区：[1]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [2]中国石油冀东油田公司勘探开发研究院,河北唐山063004

出　　处：《大庆石油地质与开发》2024年第5期1-12,共12页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家自然科学基金项目“富油凹陷压力梯度与油气运移方式量化表征”(41972141)。

摘　　要：渤海湾盆地南堡凹陷具有油气富集层系不均的特征,为了揭示断层对油气差异富集的控制作用,通过分析油源断层类型、活动性及输导能力,得到了研究区断-源、断-盖等配置关系,建立了深、浅层油气富集模式。结果表明:南堡凹陷发育Ⅰ、Ⅱ、Ⅲ共3类油源断层,它们分别断穿沙三段、沙一段和东三段烃源岩,各类油源断层的垂向输导能力与其活动速率密切相关,由于3类油源断层的供烃能力依次减小,油气沿Ⅰ类、Ⅱ类、Ⅲ类油源断层向东二段以上层系运移的最小活动速率依次增加;研究区油气在东二段上下层系的差异分布受油源断层活动速率和断层与东二段盖层的配置关系共同控制,断层对盖层的破坏程度控制了油气能否穿过盖层,而是否有油气沿断裂垂向运移至盖层之上则受控于被油源断层断穿的烃源岩的供烃能力及油源断层的活动强度。综合建立了“断-盖封堵”深层油气富集模式和“断-盖开启”浅层油气富集模式,合理解释了南堡凹陷各构造带油气纵向富集差异的内在原因。研究成果可为同类油藏的勘探工作提供理论依据及指导。Nanpu Sag in Bohai Bay Basin is characterized by uneven oil and gas enrichment strata series.In order to reveal controlling effect of faults on differential enrichment of oil and gas,the types,activity and transport capacity of oil-source faults are analyzed to obtain fault-source and fault-caprock configuration relationships in studied area and to establish deep and shallow oil and gas enrichment patterns.The results show that ClassⅠ,ⅡandⅢoil-source faults developed in Nanpu Sag,cutting through source rocks of Sha-3 Member,Sha-1 Member and Dong-3 Member respectively.Vertical transport capacity of oil-source faults is closely related to their activity rate.As hydro-carbon supplying capacity of 3 classes of oil-source faults decreases successively,the minimum activity rate of oil and gas migration along ClassⅠ,ⅡandⅢoil-source faults to strata series above Dong-2 Member(Ed2)increases successively.Differential distribution of oil and gas in the strata above and below Ed2 in studied area is controlled by both the activity rate of oil-source faults and the configuration relationship between the faults and caprocks of Ed2.Faults damage to caprock controls whether oil and gas can pass through caprock,while whether oil and gas can mi-grate vertically to strata above caprock along faults is controlled by hydrocarbon supplying capacity of source rocks and activity intensity of oil-source faults.Deep oil and gas enrichment pattern of“fault-caprock sealing”and shal-low hydrocarbon enrichment pattern of“fault-caprock opening”are established comprehensively,rationally giving the internal cause for vertical hydrocarbon enrichment difference of different structural belts in Nanpu Sag.The research provides theoretical reference and guidance for exploration of similar reservoirs.

关 键 词：南堡凹陷 油源断裂 断层活动性 断-盖配置 油气富集模式 

分 类 号：TE122.3[石油与天然气工程—油气勘探]