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1.
大陆边缘成矿   总被引:26,自引:12,他引:14  
大陆陆壳的形成与发展经历了陆核—地块 (台 )—联合大陆—大陆裂解—陆缘增生—碰撞造山的演化过程。地壳通过不均一性分异而形成大陆型和大洋型地壳,大陆裂解、洋壳向陆缘消减和陆 -陆碰撞拼接则形成具有不同构造特征的大陆边缘。以中国大陆已存在的 3条陆壳对接消减带为界划分了 5个大陆边缘构造带,进一步区分出 13个次一级的边缘构造区及其内的 53个时空配置结构,并据现有矿产地计算了边缘构造区的矿产发现几率。将中国大陆边缘划分为离散型、会聚型、对接型和转换型 4类,总结了其成矿系列类型专属;认为大陆边缘普遍性成矿有利因素的耦合对成矿至关重要,而最佳耦合的机制及其发生在大陆边缘区的时空位置是圈定有利成矿靶区的关键科学问题。  相似文献   

2.
地壳通过不均一性分异形成大陆型地壳和大洋型地壳, 陆核及地块的形成、大陆裂解与增生、洋壳的新生与消减、陆-陆碰撞拼接形成具有不同构造特征的海陆构造区。中国海陆构造演化经历了太古宙陆核形成、元古宙陆块形成、震旦纪至三叠纪联合大陆形成、中新生代联合大陆解体4个阶段, 形成北方(准噶尔—大兴安岭)、北部(塔里木—华北)、南部(扬子—华南)、南方(冈底斯—喜马拉雅), 东部(滨西太平洋)5个大陆及陆缘构造区。太古宙花岗绿岩带、元古宙裂谷(裂陷)带、显生宙大陆边缘是最重要的海陆成矿环境。海陆成矿有利因素的耦合对成矿至关重要, 而最佳耦合的机制及其发生在海陆构造区的时空位置是圈定有利成矿靶区、引导找矿突破的关键科学问题。  相似文献   

3.
地球块体不均一性边界存在地球化学急变带 ,控制大型矿床的分布 ;深部构造或隐性的构造面与地壳浅表形成的矿集区有明显的空间和形成机制耦合关系。地球化学急变带在大陆内部往往沿着一些古大陆边缘展布 ,与地壳下部和上地幔的深部构造或扩展到地幔的不连续面具有相联系的空间组合关系 ,反映壳幔相互作用对深部构造效应和大规模成矿热流体的控制。东秦岭金属矿化集中区的大型或超大型矿床沿古大陆边缘产出 ,并受地球化学急变带与地球物理梯度带交叉效应控制 ,揭示了深部构造对大型矿集区的制约。  相似文献   

4.
本区地壳演化分:太古—早元古代构造基底形成、中晚元古代大陆边缘、早古生代裂谷形成与晚古生代海槽演化四个阶段。重晶石矿床成矿作用有火山喷流作用、大陆边缘沉积作用与裂谷带多种成矿作用的叠加,是形成大型超大型重晶石矿床重要特征。本区寻找重晶石矿前景是乐观的。  相似文献   

5.
华北古大陆南缘的金属成矿作用   总被引:10,自引:2,他引:10       下载免费PDF全文
东秦岭大部分金属矿床集中分布于华北古大陆南部边缘,以陆缘构造发展阶段的赋矿沉积建造和岩石组合划分成矿系统;前长城纪陆核活动性边缘沉积成矿系统;中、新元古代被动大陆边缘成矿系统;早加里东期构造体制转换期成矿系统;中生代陆内碰撞造山成矿系统,按矿床形成作用方式可以划分为:(1)构造-岩浆-流体成矿作用,主要以洛南-栾川钼(钨)多金属斑岩组合成矿系统为主,成岩方式为壳幔同熔的燕山期中酸性岩浆的浅成侵入与定位;(2)构造-建造-流体成矿作用,按不同构造作用层次再细分为中深层次的构造作用(主要形成韧性剪切带型矿床)、浅层次构造作用(主要形成构造蚀变岩型矿床)。主要的成矿作用发生在燕山期。  相似文献   

6.
东秦岭沉积建造演化与成矿   总被引:7,自引:0,他引:7       下载免费PDF全文
在华北古大陆南缘,以控制不同构造单元的断裂为界,构造格局自北而南划分如下:古大陆边缘的基底与盖层单元(华—熊陆缘带),宽坪群构造单元,二郎坪群构造单元,北秦岭(秦岭群)构造单元和南秦岭(刘岭群)构造单元。据陆缘构造发展阶段的沉积建造和岩石组合控矿因素,划分该区沉积建造演化阶段:①前长城纪陆核活动性边缘沉积建造;②中、新元古代被动大陆边缘沉积建造;③早加里东期构造体制转换期演化阶段;④古生代活动大陆边缘沉积建造;⑤中生代陆内碰撞演化阶段。从时间与空间角度,分别研究了不同构造演化阶段的成矿问题。  相似文献   

7.
东亚地区区域构造演化与构造域划分   总被引:1,自引:1,他引:0  
东亚大陆不是简单地以一个巨型前寒武纪克拉通为主体而形成的单一大陆, 而是由一些小板块和众多微陆块及其间的褶皱带或造山带组合、经长期演化而形成的复合大陆。在前人分区研究成果的基础上, 把东亚地区作为一个整体, 经系统分析和有机整合, 形成对整个东亚地区构造背景和构造演化的系统认识。研究表明, 东亚地区构造演化过程可划分为3个阶段, 即前寒武纪稳定陆壳形成阶段、古生代陆洋分化对立阶段和中新生代盆山对峙发展阶段, 尤其以中新生代以来的构造演化对东亚大陆具有重要意义。以燕山期以来东亚地区所受地球动力学背景及其在不同地区作用的差异为主要参考指标, 可将东亚地区划分为7个构造域:西部挤压构造域、西部相对稳定构造域、青藏—羌塘构造域、中部克拉通构造域、俯冲边缘构造域、东部环太平洋构造域和兴安—蒙古构造域, 构造域的划分对于研究区内沉积盆地的成盆演化历史、进行盆地类型划分和盆地油气资源潜力类比分析具有重要的指导意义。   相似文献   

8.
新疆晚古生代大陆边缘成矿系统与成矿区带初步探讨   总被引:15,自引:4,他引:15  
新疆地处中亚成矿域的中段,古生代大陆边缘增生明显、构造和岩浆活动强烈、矿产资源丰富。古生代大陆边缘成矿作用主要集中在两个时期,即以阿尔泰南缘为主的早中泥盆世和以天山为主的早石炭世。本文在综合研究及与境外对比的基础上,按照北疆地区晚古生代大陆边缘的构造动力学和成矿特征,将研究区大陆边缘成矿系统划分为:活动大陆边缘海相火山岩-盆地流体成矿系统,活动大陆边缘火山岛弧-岩浆活动成矿系统和被动大陆边缘沉积盆地-热水活动成矿系统三类。同时对形成于大陆边缘的成矿区带进行划分,主要包括:阿勒泰南缘晚古生代活动大陆边缘块状硫化物成矿带;阿尔泰南缘-东准噶尔活动大陆边缘卡拉先格尔岛弧斑岩铜金成矿带;东天山晚古生代活动大陆边缘铜钼锌成矿区带;西准噶尔洋内弧斑岩-浅成低温热液铜金成矿区带;西天山(伊犁地块)活动大陆边缘金铜成矿区带;塔里木板块被动大陆边缘沉积型铅锌成矿带。本文认为大陆增生与成矿作用的关系是矿床学和成矿系统研究的重要内容,成矿区带是成矿系统发生成矿作用的响应,而成矿系统是成矿区带形成的本质。  相似文献   

9.
云贵高原-造山带-沉积盆地的构造演化与金属矿产形成有密切关系。近南北向乌蒙山造山带和扬子地块西缘元古宙造山带(元古宙基底构造层)为元古宙铁铜和铁氧化物铜金型(IOCG)矿床集中区。在东缘滇黔桂晚古生代陆缘拉分盆地中,形成了铅锌银-金汞锑等低温热液金属矿床集中区。在个旧-文山一带形成了锡铜钨-多金属成矿集中区,并伴生铷铯铟等稀散元素。在西侧云南楚雄中新生代沉积盆地中,形成了砂岩型铜矿床集中区等。北侧四川-重庆一带形成了天青石矿床成矿集中区。这些金属矿床集中区形成与云贵高原-造山带-沉积盆地经历了多期次构造演化过程中,形成了特殊的矿田(床)构造有密切关系。这些特殊的大陆构造样式、构造组合、构造-流体-成岩成矿作用和碱性铁质基性岩类侵位的多重耦合作用,值得今后开展深入研究,为今后矿山深部找矿预测和大陆深部构造研究提供科学依据。  相似文献   

10.
中国构造-地层大区划分新方案   总被引:10,自引:0,他引:10       下载免费PDF全文
中国大陆是由泛华夏陆块群、劳亚和冈瓦纳2个大陆边缘、3个大洋(古亚洲洋、特提斯洋和太平洋)洋陆转换逐渐集合 长大而成的.在中国大陆增生过程中,经历了多个大洋岩石圈板块构造向大陆岩石圈构造转换、增生、碰撞聚集,形成了以华 北、塔里木、扬子为核心的3个陆块(地台)区、8个造山系(阿尔泰-兴蒙、天山-准噶尔-北山、秦-祁-昆、羌塘-三江、冈 底斯、喜马拉雅、华夏、台东)镶嵌组成的复式大陆.在造山系中,还包含了大洋消亡、陆陆碰撞形成的6个对接带(额尔齐斯- 西拉木伦、南天山、宽坪-佛子岭、班公湖-双湖-怒江-昌宁-孟连、雅鲁藏布、江绍-郴州-钦防).根据中国大陆的上述地 史演化特点,提出按陆块区(地台区)、造山带区和对接带区不同的大地构造环境和大地构造演化阶段、造山带区洋-陆转化 时间、生物古地理区系、地层类型与地层序列等9条原则进行全国构造-地层大区综合区划新方案.上述3大陆块区、6大对接 带和8大造山系构成了中国大陆的17个构造-地层大区.   相似文献   

11.
中国的岩金矿床与板块构造   总被引:1,自引:0,他引:1  
本文指出,中国岩金矿床的形成和分布严格地受板块构造控制。(1)裂谷带和俯冲、碰撞带等不同构造环境金的成矿特征明显不同。俯冲带金矿床还具有水平分带性,它受富金变质基底和深断裂的影响而复杂化;(2)不同构造环境金的成矿作用,既有区别,又有联系,在威尔逊构造旋回中为一连续过程,在成矿作用、矿床类型、矿质来源、矿石金属元素组合等方面均具有旋回性;(3)吕梁期和燕山期是我国最重要的金成矿期,是分别伴随太古代绿岩-裂谷带封闭和大规模俯冲、碰撞作用而发生的。在太古代绿岩带之上叠加有燕山期俯冲构造的地区,是我国最重要的金成矿集中区。  相似文献   

12.
中国陆区大规模成矿的地球动力学:以夕卡岩型金矿为例   总被引:27,自引:0,他引:27  
系统总结了中国不同构造单元 70个夕卡岩型金矿床的基本地质特征 ,其中 1个为超大型、1 9个大型和 2 4个中型矿床 ,总储量超过 1 0 0 0t,占全国探明储量的约 2 0 % ,表明夕卡岩型金矿是我国最重要金矿类型之一 ,值得今后地质研究和勘探工作重视。通过编制中国夕卡岩型金矿分布图 ,发现它们产于碰撞造山带、断裂岩浆带和活化克拉通边缘等 3类地区 ,所有夕卡岩型金矿集中区均受到显生宙陆陆碰撞的影响。通过对各成矿省夕卡岩型金矿和相关热液矿床及花岗岩类的同位素年龄统计 ,结合地质分析 ,发现中国夕卡岩型金矿的形成时间总晚于各成矿省最晚一次的洋盆闭合或陆陆碰撞的开始时间 ,约滞后 5 0Ma ,因此排除了它们形成于大洋板块俯冲所致的岩浆弧背景的可能性 ;通过联系各成矿省地质构造演化与碰撞造山带 p T t轨迹 ,确定各成矿省成矿作用和花岗岩浆作用均爆发于陆陆碰撞过程挤压伸展转变期的减压升温体制 ,而不是碰撞后。基于碰撞造山带构造几何和造山机制 ,认为中国夕卡岩型金矿及相关矿床的时空分布和成因适合于CMF模式解释  相似文献   

13.
王国灿  张攀 《地球科学》2019,44(5):1688-1704
蛇绿岩代表了古洋壳的残余,通常被作为识别古汇聚板块边界的重要标志之一.但是,通过对西准噶尔造山带和松潘-甘孜造山带内出露的蛇绿混杂岩的大比例尺填图和构造解析,揭示出并非所有的蛇绿混杂岩带都具有缝合带的大地构造意义.综合前人研究结果,将蛇绿混杂岩划分为缝合带型和非缝合带型2种类型.非缝合带型蛇绿混杂岩带的分布与残余洋盆在闭合过程中的构造过程密切相关.在残余洋盆被巨厚层的碎屑岩填充之后,作为残余盆地基底的大洋岩石圈物质在区域挤压应力作用下,可通过多种形式构造就位于上覆碎屑沉积地层之中,形成具有弥散性分布特点的残余洋盆型蛇绿混杂岩系统.而缝合带型蛇绿混杂岩的就位过程可划分为3种方式,分别是俯冲就位、仰冲就位和碰撞就位.这些不同类型的蛇绿混杂岩带在板块汇聚后的再造山过程中,早期的构造变形会被叠加改造甚至导致蛇绿混杂岩的重新就位,使其分布形式复杂化.因此,正确识别和厘定不同构造过程形成的蛇绿混杂岩带及其对应的大地构造背景,对研究洋陆转换过程和造山带的演化至关重要.  相似文献   

14.
三江特提斯复合造山与成矿作用研究进展   总被引:69,自引:57,他引:12  
邓军  杨立强  王长明 《岩石学报》2011,27(9):2501-2509
国家973规划项目"三江特提斯复合造山与成矿作用"实施3年来,在成矿动力学背景、增生造山成矿系统、碰撞造山成矿系统、构造体制转换与复合叠加成矿作用、成矿预测理论和勘查技术集成等方面取得了重要进展。(1)厘定了原特提斯、古特提斯、新特提斯和陆陆碰撞等一系列重要的区域构造-岩浆事件及其动力学背景,提出存在较大规模的燕山期构造-岩浆-成矿事件。(2)划分了被动边缘盆地型、活动边缘多岛弧盆型和大洋盆地型3个VMS型Cu-Pb-Zn成矿子系统,确立了玉龙和格咱-香格里拉斑岩型Cu矿带印支期岩浆作用的贡献及俯冲岛弧构造环境。(3)沉积岩容矿Pb-Zn-Cu-Ag多金属矿床的形成贯穿于印-亚大陆碰撞的三个演化阶段,成矿年代由南向北逐渐变新;它包括2套子系统:脉状Cu成矿系统,与变质流体活动有关,成矿物质来自深部地壳和浅部沉积地层的混合;Pb-Zn(-Cu-Ag)成矿系统,与盆地流体活动有关,成矿物质主要来自沉积地层。(4)金沙江-哀牢山斑岩型Cu(Au)成矿系统形成于35Ma左右,受控于印-亚大陆碰撞导致的地壳增厚。(5)造山型Au成矿系统主要发育在哀牢山金矿带,三期金成矿作用发生于~62Ma、~35Ma和28Ma左右,分别受控于印-亚碰撞早期的强烈汇聚挤压、早-晚期转换构造动力学体制。(6)区域存在3期重要构造体制转换事件:增生造山→碰撞造山、主碰撞→晚碰撞和晚碰撞→后碰撞,前两者控制区域斑岩铜矿带、沉积岩容矿多金属矿带和造山型金矿带,后者控制了沱沱河盆地中的Pb-Zn矿床。(7)最典型的叠加成矿系统为VMS 型Cu-Pb-Zn与斑岩型Cu叠加成矿系统,主要发育于羊拉-红山-普朗-铜厂沟矿集区、云县-景谷、江达-维西和昌宁-孟连成矿带。(8)探索成矿预测理论与方法,并选择羊拉-红山-普朗-铜厂沟矿集区为重点地区,开展隐伏矿体预测工作,取得找矿进展。本专辑论文基本覆盖了上述各个方面的研究进展,论文涉及4个主题:成矿动力学背景、增生造山成矿系统、碰撞造山成矿系统、构造体制转换与复合叠加成矿作用。  相似文献   

15.
The Tethyside orogen, a direct consequence of the separation of the Gondwanaland and the accretion of Eurasia, is a huge composite orogenic system that was generated during Paleozoic–Mesozoic Tethyan accretionary and Cenozoic continent–continent collisional orogenesis within the Tethyan domain. The Tethyside orogenic system consists of a group of diverse Tethyan blocks, including the Istanbul, Sakarya, Anatolide–Taurides, Central Iran, Afghanistan, Songpan–Ganzi, Eastern Qiangtang, Western Qiangtang, Lhasa, Indochina, Sibumasu, and Western Burma blocks, which were separated from Gondwana, drifted northwards, and accreted to the Eurasian continent by opening and closing of two successive Tethyan oceanic basins (Paleo-Tethyan and Neo-Tethyan), and subsequent continental collision.The Tethyan domain represents a metallogenic amalgamation across diverse geodynamic settings, and is the best endowed of all large orogenic systems, such as those associated with the Cordilleran and Variscan orogenies. The ore deposits within the Tethyan domain include porphyry Cu–Mo–Au, granite-related Sn–W, podiform chromite, sediment-hosted Pb–Zn deposits, volcanogenic massive sulfide (VMS) Cu–Pb–Zn deposits, epithermal and orogenic Au polymetallic deposits, as well as skarn Fe polymetallic deposits. At least two metallogenic supergroups have been identified within the eastern Tethyan metallogenic domain (ETMD): (1) metallogenesis related to the accretionary orogen, including the Zhongdian, Bangonghu, and Pontides porphyry Cu belts, the Pontides, Sanandaj–Sirjan, and Sanjiang VMS belts, the Lasbela–Khuzdar sedimentary exhalative-type (SEDEX) Pb–Zn deposits, and podiform chromite deposits along the Tethyan ophiolite zone; and (2) metallogenesis related to continental collision, including the Gangdese, Yulong, Arasbaran–Kerman and Chagai porphyry Cu belts, the Taurus, Sanandaj–Sirjan, and Sanjiang Mississippi Valley-type (MVT) Pb–Zn belts, the Southeast Asia and Tengchong–Lianghe Sn–W belts or districts, the Himalayan epithermal Sb–Au–Pb–Zn belt, the Piranshahr–Saqez–Sardasht and Ailaoshan orogenic Au belts, and the northwest Iran and northeastern Gangdese skarn Fe polymetallic belts. Mineral deposits that are generated with tectonic evolution of the Tethys form in specific settings, such as accretionary wedges, magmatic arcs, backarcs, and passive continental margins within accretionary orogens, and the foreland basins, foreland thrust zones, collisional sutures, collisional magmatic zones, and collisional deformation zones within collisional orogens.Synthesizing the architecture and tectonic evolution of collisional orogens within the ETMD and comparisons with other collisional orogenic systems have led to the identification of four basic types of collision: orthogonal and asymmetric (e.g., the Tibetan collision), orthogonal and symmetric (Pyrenees), oblique and symmetric (Alpine), and oblique and asymmetric (Zagros). The tectonic evolution of collisional orogens typically includes three major processes: (1) syn-collisional continental convergence, (2) late-collisional tectonic transform, and (3) post-collisional crustal extension, each forming distinct types of ore deposits in specific settings. The resulting synthesis leads us to propose a new conceptual framework for the collision-related metallogenic systems, which may aid in deciphering relationships among ore types in other comparable collisional orogens. Three significant processes, such as breaking-off of subducted Tethyan slab, large-scale strike-slip faulting, shearing and thrusting, and delamination (or broken-off) of lithosphere, developed in syn-, late- and post-collisional periods, repsectively, were proposed to act as major driving forces, resulting in the formation of the collision-related metallogenic systems. Widespread appearance of juvenile crust and intense inteaction between mantle and crust within the Himalayan–Zagros orogens indicate that collisional orogens have great potential for the discovery of large or giant mineral deposits.  相似文献   

16.
李荫槐 《地质科学》1984,(2):127-138
青藏高原是地球上最高大和最雄伟的年青隆起区。对于它的形成和演化机制,一直是国内外地质和地球物理学者注意的问题之一。 近十年来,人们认为青藏高原的形成是由于相距千里之遥的印度板块向北漂移并与欧亚板块碰撞的结果。然而,根据作者对喀喇昆仑和喜马拉雅等地的野外考察及其深部地球物理资料的研究,提出青藏高原原来是一个统一的前震旦纪陆壳区,后经震旦纪以来多次的拉开和挤压碰撞而形成的新观点。这种拉开和挤压的运动方式,是深部鳗隆和慢拗的分异作用引起的。  相似文献   

17.
喜马拉雅构造-成矿域及其成矿效应初步分析   总被引:7,自引:0,他引:7  
通过近年来的研究 ,提出了全新的喜马拉雅构造 -成矿域概念。从大喜马拉雅构造域及其成矿效应出发 ,通过构造域对矿集区的控制作用、成矿时代、成矿物质来源、深部过程与成矿效应的分析 ,从而较全面地评价了青藏高原及邻区的资源潜力和需要进一步工作的重要成矿带或矿集区。通过分析认为喜马拉雅构造 -成矿域内强烈的壳幔物质交换 ,下地壳翻天覆地的物质和流体交换 ,导致了在同一构造地质单元内可以有一个或多个超大型矿床的存在。并对多个重要矿床类型提出了更切合实际的观点 ,如西藏甲马铜钼银铅锌金多金属矿床属于矽卡岩 -斑岩复合型 ,云南羊拉铜钼金多金属矿床也属于矽卡岩 -斑岩复合型矿床等。在喜马拉雅构造域内形成的燕山晚期或喜马拉雅期矿床大多和大陆地壳深部复杂的动力学过程有关 ,所形成的矿床矿物组合及成矿元素组合复杂 ,特别是矿石中钴、银元素含量较高 ,许多矿床中银、钴已经作为主要成矿元素。最后明确提出了青藏高原主体及东缘重要矿集区的资源潜力  相似文献   

18.
We present a review of major gold mineralization events in China and a summary of metallogenic provinces, deposit types, metallogenic epochs and tectonic settings. Over 200 investigated gold deposits are grouped into 16 Au-metallogenic provinces within five tectonic units such as the Central Asian orogenic belt comprising provinces of Northeast China and Tianshan-Altay; North China Craton comprising the northern margin, Jiaodong, and Xiaoqinling; the Qinling-Qilian-Kunlun orogenic belt consisting of the West Qingling, North Qilian, and East Kunlun; the Tibet and Sanjiang orogenic belts consisting of Lhasa, Garzê-Litang, Ailaoshan, and Daduhe-Jinpingshan; and the South China block comprising Youjiang basin, Jiangnan orogenic belt, Middle and Lower Yangtze River, and SE coast. The gold deposits are classified as orogenic, Jiaodong-, porphyry–skarn, Carlin-like, and epithermal-types, among which the first three types are dominant.The orogenic gold deposits formed in various tectonic settings related to oceanic subduction and subsequent crustal extension in the Qinling-Qilian-Kunlun, Tianshan-Altay, northern margin of North China Craton, and Xiaoqinling, and related to the Eocene–Miocene continental collision in the Tibet and Sanjiang orogenic belts. The tectonic periods such as from slab subduction to block amalgamation, from continental soft to hard collision, from intracontinental compression to shearing or extension, are important for the formation of the orogenic gold deposits. The orogenic gold deposits are the products of metamorphic fluids released during regional metamorphism associated with oceanic subduction or continental collision, or related to magma emplacement and associated hydrothermal activity during lithospheric extension after ocean closure. The Jiaodong-type, clustered around Jiaodong, Xiaoqinling, and the northern margin of the North China Craton, is characterized by the involvement of mantle-derived fluids and a temporal link to the remote subduction of the Pacific oceanic plate concomitant with the episodic destruction of North China Craton. The Carlin-like gold metallogenesis is related to the activity of connate fluid, metamorphic fluid, and meteoric water in different degrees in the Youjiang basin and West Qinling; the former Au province is temporally related to the remote subduction of the Tethyan oceanic plate and the later formed in a syn-collision setting. Porphyry–skarn Au deposits are distributed in the Tianshan-Altay, the Middle and Lower Yangtze River region, and Tibet and Sanjiang orogenic belts in both subduction and continental collision settings. The magma for the porphyry–skarn Au deposits commonly formed by melting of a thickened juvenile crust. The epithermal Au deposits, dominated by the low-sulfidation type, plus a few high-sulfidation ones, were produced during the Carboniferous oceaic plate subduction in Tianshan-Altay, during Early Cretaceous and Quaternary oceanic plate subduction in SEt coast of South China Block, and during the Pliocene continental collision in Tibet. The available data of different isotopic systems, especially fluid D–O isotopes and carbonate C–O systems, reveal that the isotopic compositions are largely overlapping for different genetic types and different for the same genetic type in different Au belts. The isotopic compositions are thus not good indicators of various genetic types of gold deposit, perhaps due to overprinting of post-ore alteration or the complex evolution of the fluids.Although gold metallogeny in China was initiated in Cambrian and lasted until Cenozoic, it is mainly concentrated in four main periods. The first is Carboniferous when the Central Asian orogenic belt formed by welding of micro-continental blocks and arcs in Tianshan-Altay, generating a series of porphyry–epithermal–orogenic deposits. The second period is from Triassic to Early Jurassic when the current tectonic mainframe of China started to take shape. In central and southern China, the North China Craton, South China Block and Simao block were amalgamated after the closure of Paleo-Tethys Ocean in Triassic, forming orogenic and Carlin-like gold deposits. The third period is Early Cretaceous when the subduction of the Pacific oceanic plate to the east and that of Neo-Tethyan oceanic plate to the west were taking place. The subduction in eastern China produced the Jiaodong-type deposits in the North China Craton, the skarn-type deposits in the northern margin (Middle to lower reaches of Yangtze River) and the epithermal-type deposits in the southeastern margin in the South China Block. The subduction in western China produced the Carlin-like gold deposits in the Youjiang basin and orogenic ones in the Garzê-Litang orogenic belt. The Cenozoic is the last major phase, during which southwestern China experienced continental collision, generating orogenic and porphyry–skarn gold deposits in the Tibetan and Sanjiang orogenic belts. Due to the spatial overlap of the second and third periods in a single gold province, the Xiaoqinling, West Qinling, and northern margin of the North China Craton have two or more episodes of gold metallogeny.  相似文献   

19.
铁格隆地区含矿岩石以闪长玢石及石英闪长玢岩为主,属钙碱性岩系和高钾钙碱性岩系,显示I型花岗岩的特点。岩体形成于早白垩世班公湖-怒江洋盆俯冲消减构造环境,成岩岩浆属氧化型岩浆,来源于壳幔结合部,并受到壳源物质的强烈混染。与玉龙、冈底斯斑岩矿带含矿岩石进行对比,该含矿玢岩在岩石类型、岩石化学、地球化学及成岩构造环境等方面均存在明显差异,指示其成矿动力学背景、成矿机理与"碰撞"及"碰撞后"的斑岩型矿床不同,属形成于"岛弧"环境的斑岩型铜金矿床。  相似文献   

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