西湖凹陷木广迎地区断陷层地质结构与油气勘探意义  

Geological structure and its significance for petroleum exploration of fault structural layer in the Muguangying area,Xihu Sag

作　　者：周兴海曹倩 单帅强 梁世友[1,2] 王斌 王苗[1,2] 周兴海[3] 曹倩[1,2] 张晨雨 陈拥锋[1,2] Shan Shuaiqiang;Liang Shiyou;Wang Bin;Wang Miao;Zhou Xinghai;Cao Qian;Zhang Chenyu;Chen Yongfeng(Wuxi Research Institute of Petroleum Geology,Research Institute of Petroleum Exploration and Production,SINOPEC,Wuxi,Jiangsu 214126;SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms,Wuxi,Jiangsu 214126;SINOPEC Shanghai Offshore Oil&Gas Company,Shanghai 200120)

机构地区：[1]中国石化石油勘探开发研究院无锡石油地质研究所,江苏无锡214126 [2]中国石化油气成藏重点实验室,江苏无锡214126 [3]中国石化上海海洋油气分公司,上海200120

出　　处：《地质科学》2024年第3期831-840,共10页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：中国石化“十四五”资源评价方法与数据库建设项目(编号:P23229);西湖凹陷斜坡带油气成藏条件及目标评价项目 (编号:P19027-6)资助。

摘　　要：西湖凹陷是东海陆架盆地内规模最大的富油气凹陷,保俶斜坡带是凹陷内油气勘探的主要地区。近期勘探实践表明,斜坡带深层构造—岩性领域具有良好的勘探前景。开展斜坡带北部木广迎地区深部断陷层地质结构与油气勘探潜力分析,对于明确西湖凹陷构造—岩性领域下步有利突破方向具有重要意义。本文综合利用高精度三维地震和钻井资料,开展木广迎地区精细的构造和层位解释。根据解释结果进行埋藏史—热演化史模拟,并系统分析区内油气地质条件。研究表明,木广迎构造带整体表现为东倾斜坡,北部发育古新统厚度中心;区内发育走向为NE、NNE和NW向的3组断裂,多数断裂的主活动时期为古新世—始新世,活动强度逐渐减弱;木广迎地区现今古新统残留厚度为200~1500 m,暗色泥岩厚度为100~700 m,最厚可达700 m以上,其主体于宝石组沉积时期进入成熟阶段;宝石组内发育大套厚层砂岩,且物性较好,可作为有利储层。研究认为,木广迎地区发育良好的生—储—盖组合和有效的源—储配置,是西湖凹陷斜坡带构造—岩性领域勘探的有利方向。The Xihu Sag is the largest hydrocarbon-rich sag in the East China Sea Shelf Basin,and the Baochu Slope located in the western part of the sag is the main area for petroleum exploration.Recent practices have shown that the deep structural-lithological field of slope has good exploration prospects.Conducting an analysis of the geological structure and petroleum exploration potential of the deep fault structural layer in Muguangying area is of great significance for clarifying the favorable breakthrough direction in the structural-lithological field of the Xihu Sag.This study comprehensively utilizes high-resolution 3D seismic and drilling data to carry out detailed structural and stratigraphic interpretation in the Muguangying area.Based on the interpretation results,burial-thermal history of the study area is simulated,and the petroleum geology conditions are analyzed systematically.This study shows that the Muguangying structural belt is featured by an eastward dipping slope,with a Paleocene thickness center locates in its northern part.Three sets of faults with NE,NNE and NW striking directions develop in the study area,most of which were active from the Paleocene to Eocene,and their activity intensity gradually weakened.The residual thickness of the Paleocene in the Muguangying area is 200~1500 m,of which the thickness of dark mudstone is 100~700 m,with a maximum thickness exceeding 700 m.The main body of the dark mudstone entered mature stage during the sedimentary period of the Baoshi Formation.Multiple layers of thick sandstone are developed within the Baoshi Formation,which have good physical properties and can serve as favorable reservoirs.The results demonstrate that the Muguangying area has suitable source-reservoir-cap assemblage and effective source-reservoir configurations,making it a favorable direction for further exploration in the structural-lithological fields of the Baochu Slope.

关 键 词：保俶斜坡 木广迎地区 断陷层 地质结构 勘探意义 东海陆架盆地 

分 类 号：P542[天文地球—构造地质学] P618.130[天文地球—地质学]