沉积盆地构造变形序列Ⅰ：秦岭晚古生代拉分盆地的构造组合与金-铜铅锌多金属矿集区构造  

Tectonic deformation sequences of sedimentary basins:Ⅰ．Associations of tectonic deformation in late Paleozoic pull-apart basin and Au-Cu-Pb-Zn-polymetallic ore-concentrated areas in the Qinling Orogenic Belt

作　　者：方维萱[1] 黄转盈 FANG Weixuan;HUANG Zhuanying(Innovation Laboratory of Mine Ecology,Enviroment and Mineral,China Non-ferrous Metals Resource Geological Survey,Beijing 100012,China;Kunming University of Science and Technology/Southwest Institute of China Non-ferrous Metals Resource Geological Survey,Kunming 650093,China)

机构地区：[1]有色金属矿产地质调查中心矿山生态环境资源创新实验室,北京100012 [2]昆明理工大学/有色金属矿产地质调查中心西南地质调查所,云南昆明650093

出　　处：《地学前缘》2019年第5期53-83,共31页Earth Science Frontiers

基　　金：国家自然科学基金项目（41730426,41030423）;云南省矿产资源预测评价工程实验室（2010）;云南省地质过程与矿产资源创新团队项目（2012）;国土资源部公益性行业基金项目（201511016-1）

摘　　要：研究秦岭晚古生代拉分盆地构造变形序列、构造样式、构造组合与卡林型-类卡林型金矿床、SEDEX型银铜铅锌-重晶石-菱铁矿矿床富集成矿之间关系,对提升秦岭金属矿集区构造与金属大规模富集成矿规律的认识,具有重要意义。陕西柞山和凤太晚古生代拉分盆地是卡林型-类卡林型金矿矿集区和SEDEX型银铜铅锌矿集区,采用构造岩相学研究新方法,对晚古生代拉分盆地的构造变形序列、构造样式和构造组合、构造变形型相及与金-铜铅锌矿床改造-叠加成矿作用进行研究。认为秦岭晚古生代陆缘拉分盆地的构造变形序列和构造组合为:(1)在石炭纪-中三叠世陆-陆斜向俯冲消减体制下盆地反转期,构造-热事件和构造岩相学组合类型包括石炭纪-二叠纪构造-热事件、顺层走滑伸展变形与深源碱性热流体叠加事件,形成了泥盆系中顺层剪切变形[DS1(D-S0//S1)]、Na-K-Cl-F型热流体渗滤交代岩相[DS1a-h-S1//S0+S1#S0]、碱性热流体叠加构造岩相[DS1(FB-D3j+D3x)]和热液叠加角砾岩构造系统[DS1c(Ab-D3)],为中深构造层次(20.4~25.97km)韧性变形域下形成的变形构造型相。形成了柞山地区穆家庄铜矿床和桐木沟铅锌矿床,热液角砾岩构造系统以柞山万丈沟-二台子金铜矿床和凤太双王-青岩沟金矿床为代表。(2)在印支期陆-陆全面碰撞挤压体制下,在晚古生代陆缘拉分盆地内部,盆内变形构造组合和构造-岩浆热事件为冲断褶皱带+W-M型复式褶皱-压扭性断裂带+切层脆韧性剪切变形(DS2)+隐伏岩浆侵入构造系统,它们为中构造层次(11~17km)脆韧性变形域下形成的变形构造型相。在柞山晚古生代陆缘拉分断陷盆地南北两侧边界同生断裂带,转变为南向厚皮型逆冲推覆构造系统,夏家店造山型金矿床受山阳-凤镇断裂带的镇安-板岩镇次级断裂和厚皮型冲断褶皱带控制,金矿体定位于切层和顺层脆韧性剪切带中Researches on tectonic deformation sequences,tectonic styles and tectonic associations for late Paleozoic pull-apart basins,and their relationships with the Carlin-type or Carlin-like gold deposits and SEDEX-type Ag-Cu-Pb-Zn-barite-siderite deposits in the Qinling Orogenic Belt,are very useful in obtaining a better understanding of the metal ore-concentrated areas and factors controlling large-scale mineralization.The Zhashan and Fengtai late Paleozoic pull-apart basins are two ore-concentrated areas for Carlin-type or Carlin-like gold deposits and SEDEX-type Ag-Cu-Pb-Zn-barite-siderite deposits.In this report,using a new method of tectonic lithofacies,we studied the tectonic deformation sequences,tectonic styles,tectonic associations and pattern-phase of deformation tectonics for the Zhashan and Fengtai late Paleozoic pull-apart basins in the Qinling Orogenic Belt,and relationships among reworking and superimposing mineralization of Au-Ag-Cu-Pb-Zn deposits.Tectonic deformation sequences and deformation tectonic associations for late Paleozoic pull-apart basins on the northern margin of the Qinling micro-block may be classified into four stages as follows:(1)tectonic-thermal event and tectonic associations,including C-P tectonic-heating event,events of layering shear rheology tectonics and zone of alkaline hydrothermal brecciation at depth,during the basin-inversion stage from the Carboniferous period to the Middle Triassic epoch(DS1),formed by the oblique-directed subduction of continent to continent.These tectonic associations consisted of the tectonic lithofacies patterns of layering shear rheology tectonics of the Devonian strata[DS1(D-S0//S1)],Na-K-Cl-F-type percolating-replacement lithofacies of thermal-fluids[DS1 a-h-S1//S0+S1#S0],superimposed lithofacies of alkaline hot-fluid’s brecciation [DS1(FB-D3 j+D3 x)],and tectonic systems of hypothermal fluid’s brecciation [DS1c(Ab-D3)].All of these tectonic lithofacies and tectonic associations may be attached to the pattern-phase at the middle-deep level(20.

关 键 词：拉分盆地 构造变形序列 构造变形样式 变形构造型相 矿集区 卡林型-类卡林型金矿 SEDEX型银铜铅锌-重晶石-菱铁矿矿床 秦岭造山带 

分 类 号：P54[天文地球—构造地质学] P611[天文地球—地质学]