渤中13-2双层结构太古宇潜山成藏条件分析与勘探发现  

Analysis of hydrocarbon accumulation conditions of double-layered Archaeozoic buried hill and major discovery of Bozhong 13-2 Oil and Gasfield,Bohai sea area

作　　者：施和生 牛成民 侯明才 高阳东 赖维成 陈安清 徐国盛 许鹏 曹海洋 阎建国 Shi Hesheng;Niu Chengmin;Hou Mingcai;Gao Yangdong;Lai Weicheng;Chen Anqing;Xu Guosheng;Xu Peng;Cao Haiyang;Yan Jianguo(Exploration Department of CNOOC Co.,Ltd.;Bohai Petroleum Research Institute of CNOOC(China)Co.,Ltd.Tianjin Branch;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology;Shenzhen Branch of CNOOC(China)Co.,Ltd.)

机构地区：[1]中海石油(中国)有限公司勘探部,100010 [2]中海石油(中国)有限公司天津分公司渤海石油研究院 [3]成都理工大学油气藏地质及开发工程国家重点实验室 [4]中海石油(中国)有限公司深圳分公司

出　　处：《中国石油勘探》2021年第2期12-20,共9页China Petroleum Exploration

基　　金：国家科技重大专项“渤海海域勘探新领域及关键技术研究”(2016ZX05024-003)。

摘　　要：潜山已成为中国海域油气勘探的一个重要领域,并且向大于3500m的深埋潜山拓展。渤中19-6单层太古宇变质岩潜山大气田发现之后,多层结构的潜山成藏潜力大小成为急需解决的瓶颈。通过钻井、地震资料和地球化学数据,开展区域地质构造演化研究及成藏条件分析,结果表明:基于成山成储受控于区域构造活动及其相关的裂缝作用的认识,获得了渤中13-2油气田勘探发现(探明地质储量亿吨级油气当量),证实多层结构潜山的太古宇变质花岗岩具有极好的成藏条件;通过进一步对渤中13-2油气田的成藏要素分析及其与渤中19-6大气田的对比表明,多期立体网状裂缝及其与供烃窗口的连通性是潜山成储—成藏的关键,与断裂伴生的“短轴状不连续反射”可以作为太古宇潜山优质储层的识别标志;超压宽窗供烃—多元联合输导驱动了双层结构潜山成藏,网状连通的孔—缝体系为油气在潜山内部的运移聚集提供了有效空间。渤中13-2双层结构潜山油气发现,再次证实了裂缝为主导的非沉积岩潜山勘探思路,对中国海域潜山勘探具有重要的指导意义。Buried hill has become an important field for oil and gas exploration in sea areas of China and the exploration depth is extended to greater than 3500 m.After the major discovery of Bozhong 19-6 Gasfield in Archaeozoic single-layer metamorphic buried hill,hydrocarbon accumulation potential of buried hill with multi-layered structures is another geological problem to be clarified urgently.Regional geological and tectonic evolution have been studied and hydrocarbon accumulation conditions analyzed by well,seismic and geochemical data.The result shows that the development of buried hill and reservoir is controlled by regional tectonic activities and their induced fracturing.The discovery of Bozhong 13-2 Oil and Gasfield(proven geological reserves of 100 million tons of oil equivalent)confirms that the Archaeozoic multilayered metamorphic granite buried hill has excellent hydrocarbon accumulation conditions.Further analysis on accumulation elements of Bozhong 13-2 Oil and Gasfield and comparison with those of Bozhong 19-6 Gasfield show that the multi-stage stereoscopic fracture network and effective connection with hydrocarbon supply window are the key to reservoir development and hydrocarbon accumulation in buried hill.The“short-axis discontinuous reflection”associated with fault is marker of Archaeozoic high-quality buried hill reservoir.The combination of overpressure wide hydrocarbon supply window and multivariate migration path promotes accumulation in double-layered buried hill,and the well-connected pore-fracture system provides sufficient space for hydrocarbon migration and accumulation inside the buried hill.In conclusion,oil and gas discovery in Bozhong 13-2 double-layered buried hill confirms the effectiveness of exploration in non-sedimentary buried hill dominated by fractured reservoirs,which has great significance to buried hill exploration in China sea area.

关 键 词：渤中13-2 太古宇 双层结构潜山 成藏要素 

分 类 号：TE122[石油与天然气工程—油气勘探]