西湖凹陷中央背斜带N气田花港组河道型构造岩性圈闭识别与评价  

Identification and Evaluation of Channel Type Structural and Lithological Traps in the Huagang Formation of the N Gas Field in the Central Belt Zone of the Xihu Depression

作　　者：廖恒杰 娄敏 何贤科 段冬平 李炳颖 李元生 陈晨 Liao Hengjie;Lou Min;He Xianke;Duan Dongping;Li Bingying;Li Yuansheng;Chen Chen(Shanghai Branch of CNOOC Ltd,Shanghai 200335,China)

机构地区：[1]中海石油(中国)有限公司上海分公司,上海200335

出　　处：《工程地球物理学报》2024年第6期1028-1037,共10页Chinese Journal of Engineering Geophysics

基　　金：国家自然科学基金项目(编号:U19B2006);国家科技重大专项(编号:2016ZX05027-004);中海油上海有限综合科研项目(编号:E-Y423RY02.05)。

摘　　要：随着勘探开发的不断深入,目标逐渐由构造油气藏转变为岩性油气藏。西湖凹陷中央背斜带花港组河流相储层横向变化快,具备形成岩性圈闭的条件,存在较大的勘探开发潜力。通过地震沉积学、储层构型分析落实储层平面展布及砂体连通性;采用井震结合的变速成图落实砂体顶面构造;结合构造和储层刻画成果,落实构造岩性圈闭。在此基础上,结合关键成藏时期的古构造和油源断裂分布开展成藏分析,明确了岩性油气藏的油气富集主控因素。研究区发育两期河道,河道1较河道2气水界面低37.2 m。油源断裂位于西部,与河道砂体耦合关系较好,形成河道型构造岩性圈闭,具有“古隆汇聚-近断富集-一砂一藏”的特征。河道2西南侧翼部河道更靠近油源断裂,成藏潜力大,是下一步勘探评价的重要目标之一。岩性圈闭的刻画是基础,成藏主控因素分析是关键。相关方法可为其他相似地区圈闭刻画提供参考。With the development of oil and gas exploration,the target gradually changes from structural reservoirs to lithological reservoirs.The fluvial reservoir of the Huagang Formation in the central structural inversion zone of the Xihu Sag changes rapidly laterally to form lithological traps,which has a large potential for oil and gas exploration.Seismic sedimentology and reservoir architecture are used to analyse the planar distribution of reservoirs and connectivity of sand bodies.Variable-speed mapping is used to predict the top surface structure of sand bodies.Based on the results of structural and reservoir characterization the lithological traps are analysed.Integrated with the distribution of ancient structures and oil source faults during key reservoir formation periods,reservoir formation analysis is carried out to clarify the main controlling factors for oil and gas enrichment.The study area involves two stages of river channels,and the gas-water interface of channel 1 is lower than that of channel 2 by 37.2 m.The oil source fracture is located in the west,which has a better coupling relationship with the river sands and forms a river channel-type tectonic and lithological enclosure with the characteristic of“paleotectonic convergence-enrichment by near-faults-one sand,one reservoir”.The southwestern flank of channel 2 is closer to the oil source fracture,with a high potential for reservoir formation,which is one of the important targets for the next exploration and evaluation.The characterization of lithological traps constructs the foundation,and the analysis of the main controlling factors testtifiesthe key.The concerned methods offer reference for the study of similarareas.

关 键 词：西湖凹陷 河流相储层 构造岩性圈闭 储层连通性 成藏分析 

分 类 号：P631.4[天文地球—地质矿产勘探]