| 张德明,卢定彪,骆珊,吴开彬,彭成龙,龚桂源,陈兴,李月森.右江盆地北缘册亨地区滑脱构造变形及其对金矿的控制作用——来自方解石U-Pb年代学的约束[J].贵州地质,2025,42(3):353-373, 352 |
| 右江盆地北缘册亨地区滑脱构造变形及其对金矿的控制作用——来自方解石U-Pb年代学的约束 |
| Detachment Tectonic Deformation and Its Control on Gold Deposits in Ceheng Area on the Northern Margin of Youjiang Basin ——Constraints from Calcite the U-Pb Geochronology |
| 投稿时间：2025-05-27 |
| DOI： |
| 中文关键词: 卡林型金矿 滑脱构造 方解石U-Pb定年 册亨地区 右江盆地北缘 |
| 英文关键词:Carlin-type gold deposit Detachment structure Calcite U-Pb dating Ceheng area Northern margin of Youjiang Basin |
| 基金项目:贵州省地矿局“右江盆地北缘T/P界面附近滑脱构造变形及其对金矿的控制作用-以贵州册亨地区为例”项目(编号:黔地矿科合〔2020〕27号)，中国地质调查局“贵州1∶5万册亨县幅等四幅地质矿产综合调查”项目 (编号:12120115026401)，贵州省地矿局科技创新人才团队培育计划项目(黔地矿科合〔2024〕TD04)资助 |
|
| 摘要点击次数: 0 |
| 全文下载次数: 0 |
| 中文摘要: |
| 册亨地区位于右江盆地北缘，是我国西南地区卡林型金矿聚集区的重要组成部分，自晚三叠世盆地演化结束后经历了多期构造变形，并形成了以二叠系碳酸盐岩与三叠系碎屑岩接触面为主滑面和中三叠统许满组第四段中泥岩段为次级滑面，上覆三叠系罗楼组、许满组和呢罗组中的灰岩段为强烈滑脱层的多层次滑脱构造体系。在详细的野外调查、构造解析和区域金矿床成矿背景研究基础上，结合主滑面及其次级断层破碎带中方解石原位U-Pb测年结果，将区内滑脱构造变形限定于早燕山期(191〖XC线.TIF,JZ〗179 Ma)和晚燕山期(89〖XC线.TIF,JZ〗83 Ma)两个期次。结果表明研究区早燕山期以自东向西轻微挤压为特征，形成了近南北向宽缓背斜构造；晚燕山期由南往北挤压收缩强烈，向北沿主滑脱面发生多层次滑脱，斜坡-盆地区表现以脆-塑性形变为主，形成轴面南倾的近东西向紧闭线性褶皱、伴生向北逆冲的断层及低角度劈理带，而在台地边缘区发育断面、轴面倾向北为主的构造组合样式。研究区金矿(化)体主要有两种产出状态，一是顺层平缓或呈低角度产出，明显受滑脱构造变形及派生次级断裂控制；再者是陡倾产出，受切层断裂控制明显，为滑动构造递进变形结果。由此，本文认为研究区金矿主要形成于燕山期，与滑脱构造变形关系密切，即主滑面为含金热液较好的导、容矿构造，而地表靠近滑面发育的次级断裂、褶皱等为金矿容矿构造。 |
| 英文摘要: |
| The Ceheng area located on the northern margin of the Youjiang Basin, is an important part of the Carlin-type gold deposit concentration area in southwest China. Since the end of the Late Triassic basin evolution, it has experienced multiple phases of tectonic deformation and forming a multi-level detachment structure system. This system takes the contact surface between Permian carbonate rocks and Triassic clastic rocks as the main sliding surface, the middle mudstone member of the 4 th member in theXuman formation of Middle Triassic as the secondary sliding surface, and the limestone members in the Luolou formation of the overlying Triassic, Xuman formation and Niluo formation as the intense detachment layers. Under the constraints of detailed field investigations, structural analysis, and the metallogenic background of regional gold deposits, combined with the in-situ U-Pb dating results of calcite in the main sliding surface and its secondary fault fracture zones, the detachment structural deformation in the area is confined to two phases: the Early Yanshanian (191〖XC线.TIF,JZ〗179 Ma) and the Late Yanshanian (89〖XC线.TIF,JZ〗83 Ma). The results show that during the Early Yanshanian, the study area was characterized by slight compression from east to west, forming broad and gentle near north-south trending anticlinal structures. During the Late Yanshanian, there was strong compression and contraction from south to north, with multi-level detachment along the main sliding surface towards the north. The slope-basin area was dominated by brittle-plastic deformation, forming near east-west trending tight linear folds with south-dipping axial planes, accompanied by northward thrust faults and low-angle cleavage zones. In the platform margin area, however, a structural assemblage with fault planes and axial planes mainly dipping northward developed.There are mainly two occurrence states of gold ore (mineralized) bodies in the study area. One is gently stratified or low-angle occurrence, obviously controlled by detachment structural deformation and derived secondary fractures; the other is steeply dipping occurrence, clearly controlled by cross-stratal fractures, which is the result of progressive sliding deformation. Therefore, this paper holds that the gold deposits in the study area were mainly formed during the Yanshanian period and are closely related to detachment structural deformation. That is, the main sliding surface served as a good pathway and host structure for gold-bearing hydrothermal fluids, while the secondary fractures, folds, etc., developed near the sliding surface at the surface acted as host structures for gold deposits. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|
