东海盆地丽水凹陷T85构造变革界面的厘定及其成因模式探讨  

Deciphering Tectonic Mechanism and Origin of T85 Horizon in Lishui Depression, East China Sea Basin

作　　者：蒋一鸣 吴路路 覃军 唐贤君 张彦振 李泽宇 沈传波[2] Jiang Yiming;Wu Lulu;Qin Jun;Tang Xianjun;Zhang Yanzhen;Li Zheyu;Shen Chuanbo(Shanghai Branch of CNOOC Ltd.,Shanghai 200335,China;Key Laboratory of Tectonics and Petroleum Resources,Ministry of Education,China University of Geosciences,Wuhan 430074,China;School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo 454003,China)

机构地区：[1]中海石油(中国)有限公司上海分公司,上海200335 [2]中国地质大学构造与油气资源教育部重点实验室,湖北武汉430074 [3]河南理工大学能源科学与工程学院,河南焦作454003

出　　处：《地球科学》2024年第12期4450-4464,共15页Earth Science

基　　金：国家自然科学基金项目(Nos.42372181,42302171);湖北省自然科学创新群体项目(No.2021CFA031);中国“十四·五”重大科技项目“近海重点潜在富烃洼陷评价技术”(No.KJGG2022-0301)。

摘　　要：为了揭示东海盆地丽水凹陷T85界面上、下裂陷演化的差异,阐明构造变革的成因,研究基于钻井标定的高精度三维地震数据,精细刻画了丽水凹陷的盆地构型、断层活动性和沉降作用时空变化特征.结果表明:丽水凹陷T85界面是一个角度不整合界面,界面之下发育断控的楔形地层构型,而界面之上变为拗陷作用控制的碟形地层构型;断陷期,凹陷沉降作用向西迁移,而进入断拗期,凹陷沉降作用开始逐步向东迁移.结合区域动力学背景,研究建立了T85界面构造变革的成因模型,即构造迁移引起的热沉降模型和下地壳韧性变形的浅层响应模型.这一成果对裂陷盆地裂陷演化和成盆机制研究具有重要借鉴意义.To unravel the difference of rift evolution between the sub-and supra-T85 horizon,and illustrate the formation mechanism of the tectonic transition,the rift architecture,fault activity and spatio-temporal variations of subsidence were investigated by using high-quality seismic data and borehole data.Dividing by the T85 angular unconformity,the Lishui depression exhibits two distinct rift architecture:the underlying fault-controlled,wedge-shaped packages and the overlying saucer-shaped packages.Subsidence within the Lishui depression migrated westward during the faulting stage,while it progressively migrated eastward during the subsequent faulting and sagging stage.Together with the regional geodynamic context and advances in rift research,the study proposes that either the thermal subsidence caused by tectonic migration or the shallow response to the ductile deformation of lower crust resulted in the tectonic transition within the Lishui depression.The study significantly improves the understanding of rift evolution and its controlling factors.

关 键 词：构造变革 裂陷演化 不整合界面 丽水凹陷 东海盆地 石油地质 

分 类 号：P618[天文地球—矿床学]