摘要
褶皱冲断带-前陆盆地系统普遍受控于浅表构造剥蚀-沉积作用过程及其相关耦合机制,从而具有复杂的三维空间构造变形特征与演化过程。上扬子地块雪峰陆内褶皱冲断带,受板块碰撞的远源效应影响下,形成了无序的冲断构造。本文基于研究区内边界主断裂带构造解析、断层方解石U-Pb年代学以及对地震剖面的构造解释,对雪峰陆内褶皱冲断带的变形过程进行了梳理:(1)晚三叠世—早侏罗世(200 Ma),初步发生陆内褶皱冲断变形,慈利-保靖断裂开始活动;(2)晚侏罗世—早白垩世(160~120 Ma),多层系滑脱致使冲断变形扩展至鄂渝湘黔地区,此时建始-彭水断裂开始活动;(3)晚白垩世—早古近纪(71~52 Ma),恩施-酉阳、鹤峰-来凤断裂开始活动,进一步发生挤压褶皱冲断变形作用。断层年代学与研究区内变形应力场特征共同揭示雪峰陆内冲断系统印支期前展式冲断扩展变形过程、燕山期背驼式构造变形过程,共同形成了扬子陆块内部低楔顶角角度、宽变形域前陆冲断带结构特征,控制着上扬子地块古扬子陆相湖盆形成演化过程。
The fold-thrust belt foreland basin system is generally controlled by the process of shallow tectonic denudation-sedimentation and its related coupling mechanism,so it has complex three-dimensional tectonic deformation characteristics and evolution process.Under the remote effect of plate collision,out-ofsequence structures were formed in Xuefeng intracontinental fold and thrust belt in Upper Yangtze block.Based on the structural analysis of deep and large fault zones in the study area,fault calcite U-Pb chronology and deep structural interpretation of seismic profiles,the deformation process of Xuefeng intracontinental fold and thrust belt is reviewed.①In the Late Triassic to Early Jurassic(200Ma),the intracontinental fold thrust deformation occurred initially,and the Cili-Baojing fault began to move.②In the Late Jurassic and Early Cretaceous(160~120 Ma),the multi-layer system slip caused the thrust deformation to extend to the Hubei,Chongqing,Hunan and Guizhou regions,and Jianshi-Pengshui fault began to move.③In the Late Cretaceous-Early Palaeo-Modern period(71~52 Ma),the Enshi-Youyang and Hefeng-Laifeng faults began to move,and further extrusion folding and thrust-deformation occurred.The fault chronology and the deformation stress field in the study area jointly reveal the process of the Xuefeng intracontinental thrust system showing overthrust deformation before the Indochinese period and the back-camel structure deformation during the Yanshan period,which together form the structural characteristics of the foreland thrust belt with low wedge top angle and wide deformation area in the Yangtze landmass,and control the formation and evolution of the ancient Yangtze continental lake basin in the Upper Yangtze block.
作者
邓宾
徐宏远
李英强
涂国煜
姜磊
李智
刘重江
何泽亮
雍自权
刘树根
DENG Bin;XU Hongyuan;LI Yingqiang;TU Guoyu;JIANG Lei;LI Zhi;LIU Chongjiang;HE Zeliang;YONG Ziquan;LIU Shugen(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu,Sichuan 610059,China;Sinopec Petroleum Exploration and Production Research Institute,Beijing 100083,China)
出处
《地质学报》
北大核心
2025年第8期2565-2580,共16页
Acta Geologica Sinica
基金
省科技厅创新团队项目(编号2022JDRC0001)
国家自然科学基金项目(编号42230310)联合资助的成果。
作者简介
邓宾,男,1980年生。博士,教授,矿产普查与勘探专业,主要从事含油气盆地分析与油气成藏规律研究工作。E-mail:dengbin13@mail.cdut.edu.cn。
