渤海湾盆地渤中凹陷西次洼中生界古潜山油气成藏过程  

Hydrocarbon accumulation of composite-buried hill reservoirs in the western subsag of Bozhong Sag, Bohai Bay Basin

作　　者：谢玉洪 罗小平[2,3] 王德英 徐春强 徐云龙[2,3] 侯明才[2,4] 陈安清[2,4] Xie Yuhong;Luo Xiaoping;Wang Deying;Xu Chunqiang;Xu Yunlong;Hou Mingcai;Chen Anqing(China National Offshore Oil Corp.,Beijing 100010,China;State Key Laboratory of Oil & Gas Reservoir Geologyand Exploitation//Chengdu University of Technology,Chengdu,Sichuan 610059,China;College of Energy Resources,Chengdu University of Technology,Chengdu,Sichuan 610059,China;Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu,Sichuan 610059,China)

机构地区：[1]中国海洋石油集团有限公司 [2]"油气藏地质及开发工程"国家重点实验室.成都理工大学 [3]成都理工大学能源学院 [4]成都理工大学沉积地质研究院

出　　处：《天然气工业》2019年第5期15-24,共10页Natural Gas Industry

基　　金：国家科技重大专项"渤海潜山成藏综合研究与有利勘探方向"(编号:2016ZX05024-003-010);中海石油(中国)有限公司科研项目"渤海海域潜山石油地质特征;典型油气藏成藏机理与有利勘探区带预测"(编号:CCL2014TJXZSS0870)

摘　　要：渤海湾盆地渤海海域渤中凹陷西次洼油气资源丰富,在浅层新近系、古近系以及深层中生界均有油气被发现,但目前对其油气聚集成藏过程以及与浅层油气藏的配置关系等尚不清楚。为了给渤中凹陷周缘的油气勘探奠定基础,运用烃源岩有机地球化学分析及生烃演化盆地模拟、流体包裹体分布特征及均一温度测定等方法和手段,结合油—源生物标志化合物特征分析,基于区域构造背景,恢复了渤中凹陷西次洼复式油气聚集成藏的过程。研究结果表明:①该区存着在古近系沙河街组三段、沙河街组一段、东营组二段下共计3套烃源岩,周缘凸起带油气储层为中生界火山岩及太古界变质岩、古近系—新近系三角洲—河流相孔隙性砂岩,该洼陷生成的油气沿断层—不整合面向斜坡带运移至周缘构造带内聚集成藏,形成了3套油气成藏组合,具有复式油气聚集带成藏的特点;②沙三段烃源岩为该洼陷内的主力烃源岩层;③上述3套组合分别经历了4个阶段的油气成藏过程——距今11～1 Ma,纵向上呈现油气优先充注深层中生界及太古界古潜山储层,后依次向上运移充注浅层古近系及新近系储层,该区油气的成藏模式为高温流体多次短期快速充注。There are abundant hydrocarbon resources in the western subsag of Bozhong sag in the Bohai Bay Basin,where oil-gas discoveries have been made in those shallow Neogene and Paleogene reservoirs and deep Mesozoic buried hill reservoirs,but no better understandings have yet been achieved in terms of the process of hydrocarbon accumulation and the relationship between deep buried hill reservoirs and the allocation of shallow reservoirs.Based on the organic geochemical analysis of source rocks and basin modeling of hydrocarbon generation evolution,distribution characteristics of fluid inclusion and homogeneous temperature measurement,combined with the characteristics of oil-source biomarkers,the process of hydrocarbon accumulation in this study area was resumed based upon the regional tectonic background.The following findings were obtained.(1)There are 3 sets of source rocks in the third and first members of Paleogene Shahejie Fm,and the second lower member of Paleogene Dongying Fm;the reservoirs in the peripheral uplift zones include Mesozoic volcanic rocks,Archean metamorphic rocks,and Paleogene-Neogene delta-fluvial porous sandstones.Hydrocarbon generated in this sag migrated along the fault unconformity surface to the slope before accumulated in the peripheral tectonic zones,resulting in 3 sets of source-reservoir-caprock assemblages formed with the characteristics of reservoir formation in compound oil and gas accumulation zones.(2)The stratum in the third member of Shahejie Fm is the main source rock.(3)The above three assemblages went through four periods of generating process during the geological time of 11-1Ma.Vertically hydrocarbon sources first filled in the deep Mesozoic and Archean reservoirs,then migrated and accumulated in the shallow Neogene and Paleogene reservoirs,where multiple shore-term rapid filling of high-temperature fluids led to this typical oil and gas pooling mode.

关 键 词：渤海湾盆地 渤中凹陷西次洼 中生代 古潜山 油气复式成藏 油源对比 浅层油气藏 配置关系 

分 类 号：P618.13[天文地球—矿床学]