白云凹陷西南断阶带油气资源潜力与勘探方向  

Oil and gas resource potential and exploration direction of the southwest fault zone of Baiyun Sag

作　　者：杨东升 王龙 郭帅[1,2] 白志钊 焦保程 杨永才 梁媛媛 刘丽芳 赵钊 YANG Dongsheng;WANG Long;GUO Shuai;BAI Zhizhao;JIAO Baocheng;YANG Yongcai;LIANG Yuanyuan;LIU Lifang;ZHAO Zhao(CNOOC Research Institute Ltd.,Beijing 100028,China;National Engineering Research Center of Offshore Oil and Gas Exploration,Beijing 100028,China;Exploration and Development Department of CNOOC China Limited,Beijing 100010,China)

机构地区：[1]中海油研究总院有限责任公司,北京100028 [2]海洋油气勘探国家工程研究中心,北京100028 [3]中海石油(中国)有限公司勘探开发部,北京100010

出　　处：《中国海上油气》2025年第2期91-103,共13页China Offshore Oil and Gas

基　　金：国家自然科学基金企业创新发展联合基金重点支持项目“南海北部深水区深层温压场差异性演化对优质储层的控制机理(编号:U24B2016)”;“十三五”国家科技重大专项“大型油气田及煤层气开发(编号:2016ZX05026)”;中国海油重大科技项目“南海北部深水区已证实富烃洼陷和潜在富烃洼陷评价(编号:KJGG2022-0101)”部分研究成果。

摘　　要：白云凹陷西南断阶带一直未获勘探突破,存在区带构造演化认识不清、资源潜力不明确等问题,进而影响整个区带勘探方向的优选。基于地震、测井、地化等资料,对白云凹陷西南断阶带结构与构造演化、始新统沉积、地化特征进行了研究,进而探讨勘探潜力,优选有利勘探方向。结果表明:(1)西南断阶带受新生代裂陷伸展和走滑改造形成“横向三阶、纵向三脊”的构造格局,经历了始新世断阶带形成期、渐新世—早中新世相对隆升期以及中中新世至今热沉降期3大演化阶段;(2)西南断阶带周缘恩平组发育富氢煤型烃源岩,有机质丰度中等—很好,母质类型为Ⅱ_(2)—Ⅲ型,达到成熟—高成熟阶段;文昌组发育浅湖—半深湖相烃源岩,有机质丰度中等—好,母质类型以Ⅱ_(2)—Ⅲ型,达到高成熟—过成熟阶段,预测天然气资源量约5.2千亿m^(3)、石油资源量约1.4亿m^(3),其中北脊汇聚区资源潜力最大;(3)运移是白云凹陷西南断阶带成藏主控因素,北部构造脊近洼带是最有利勘探区,北脊倾末端白云10A是有利勘探目标。研究成果对该区下一步油气勘探部署决策提供了重要的参考依据。The southwest fault zone of Baiyun Sag has never been explored,and there are still problems such as unclear understanding of the tectonic evolution and resource potential of the zone,thus affecting the exploration direction selection for the whole zone.Based on the seismic,logging,and geochemical data,this paper studies the structural and tectonic evolution,Eocene deposition,and geochemical characteristics of the southwest fault zone of Baiyun Sag to investigate the exploration potential and select favorable exploration directions.The results are as follows.The southwest fault zone has been modified by the Cenozoic rift extension and strike slip to form a tectonic pattern of“three horizontal orders and three vertical ridges”.The fault zone experiences three major evolutionary stages,including the Eocene fault zone formation,Oligocene-early Miocene relative uplift,and middle Miocene-present thermal sedimentation.Additionally,the Enping Formation at the periphery of the southwest fault zone develops hydrogen-rich coal-type hydrocarbon source rocks,with medium to good organic matter abundance.The parent material type isⅡ_(2)-Ⅲtypes,reaching the mature-highly mature stage.The Wenchang Formation develops shallow to half-deep lake facies hydrocarbon source rocks,with medium to good organic matter abundance.The parent material type isⅡ_(2)-Ⅲtypes,reaching the highly mature-over mature stage.Meanwhile,the predicted natural gas resources and petroleum resources are estimated to be approximately 5.2 trillion cubic meters and 140 million cubic meters respectively,with the North Ridge Convergence Area having the largest resource potential.Migration is the primary controlling factor for the accumulation of the southwest fault zone in Baiyun Sag.The northern tectonic ridge near the sag is the most favorable exploration area,and Baiyun 10A at the end of the northern ridge dip is a favorable exploration target.The study provides important references for the further decision-making of oil and gas exploration and deplo

关 键 词：白云凹陷 西南断阶带 结构特征 构造演化 烃源岩 资源潜力 

分 类 号：TE122.1[石油与天然气工程—油气勘探] P744.4[天文地球—海洋科学]