南海北部深水区时深转换方法及应用——以P构造为例  

Analysis and application of time-depth conversion methods in deep-water area of the northern South China Sea:a case study of P-structure

作　　者：曾婷 刘道理 徐乐意 李杰 史运华 ZENG Ting;LIU Daoli;XU Leyi;LI Jie;SHI Yunhua(Shenzhen Company of CNOOC(China)Co.,Ltd.,Shenzhen 518054,Guangdong,China)

机构地区：[1]中海石油(中国)有限公司深圳分公司,广东深圳518054

出　　处：《石油地质与工程》2025年第2期46-51,58,共7页Petroleum Geology and Engineering

摘　　要：南海北部深水区复杂的海底地貌和沉积特点造成时间构造图上构造形态严重畸变,制约了深水区的油气勘探。以P区块为靶区进行深水区时深转换技术研究,该区位于现今陆架与陆坡过渡带,海水深度变化大,在时间构造图上,构造面积较小,但是通过海水校正后,沿海水加深方向下倾的地层具有抬升趋势,有可能形成“隐形构造”。根据实际地质及基础资料情况,利用VSP拟合法、目的层时深厚度关系拟合法、常速法、速度谱法共四种方法进行时深转换综合分析,并通过反验证法优选适合该区时深转换最佳方法,最终确定了VSP时深拟合-井点误差校正是适用于该区的最优方案,落实了P构造,提高了南海北部深水区深度预测的精度,为圈闭落实提供了更加可靠的技术支持。The complex seabed topography and sediment characteristics in the deep-water area of the northern South China Sea have resulted in serious distortions in the structural morphology on the time-depth map,posing great challenges to deep-water oil and gas exploration.This study focuses on the P block and investigates the time-depth conversion technology in deep-water area.Located in the transition zone between the continental shelf and slope,the P block exhibits large variations in water depth.Although it occupies a relatively small area on the time-depth map,the geological formations dipping in the direction of deepening water show an uplifting trend after water depth correction,potentially forming"hidden structures".According to the actual geological and basic data,the comprehensive analysis of time-depth conversion was carried out by using four methods:VSP fitting,target layer time-depth thickness relationship fitting,constant velocity and velocity spectrum.Through cross-validation,the VSP fitting with well tie error correction is determined as the optimal approach for this area.This study not only confirms the existence of the P structure but also improves the accuracy of depth prediction,providing more reliable technical support for prospect evaluation.

关 键 词：南海北部深水区 深度预测 海水校正 圈闭 时深转换 

分 类 号：P631.46[天文地球—地质矿产勘探]