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东天山古弧盆体系成矿规律与成矿模式 总被引：3，自引：1，他引：2
东天山是中亚增生型造山带的重要组成部分,随古亚洲洋的形成、演化和消亡,发育了东天山古生代弧盆体系。基于前人对东天山古生代构造演化与成矿规律的大量研究,针对以往研究相对薄弱的早古生代构造演化与成矿,本文重点论述了以卡拉塔格矿集区为代表的早古生代构造-岩浆-成矿研究新进展,从而进一步探讨了东天山古弧盆体系古生代构造演化与成矿规律。本文将东天山古弧盆体系划分为大南湖-头苏泉成矿带和阿奇山-雅满苏成矿带,又将前者划分为卡拉塔格成矿亚带和小热泉子-土屋成矿亚带;总结出其成矿具有VMS成矿系统与斑岩成矿系统共存、多种矿化类型叠加的特征;区域共发育两次大规模成矿事件,且均与大规模火山-侵入岩浆活动有关,进而构建了东天山古弧盆体系区域成矿模式;并指出东天山古生代弧-盆多方向、多期次的转换是导致该体系内VMS-斑岩型矿床共存、叠加成矿发育的主因。 相似文献
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中亚成矿域斑岩大规模成矿特征：大地构造背景、流体作用与成矿深部动力学机制 总被引：4，自引：0，他引：4
中亚成矿域夹持于西伯利亚、东欧和塔里木-华北克拉通之间,展布范围与全球显生宙大陆地壳生长最典型的增生型造山带——中亚造山带相当,并产出一系列大型—超大型斑岩铜(-金)、斑岩钼及斑岩铜(-钼)矿床。斑岩成矿作用自西向东存在明显差异,可高度概括为具‘西铜东钼、早铜晚钼’特征。基于前寒武纪基底性质、成矿大地构造背景以及斑岩成矿特征方面的系统综合研究,以重要构造线为界,将成矿域进一步划分为三个成矿省:哈萨克斯坦斑岩Cu(-Au-Mo)、蒙古斑岩Cu(-Au)和中国东北斑岩Mo(-Cu)成矿省。哈萨克斯坦成矿省具新太古—古元古代结晶基底;四个大型斑岩Cu矿床形成于早古生代增生造山过程(481~440Ma),而绝大多数矿床为晚石炭世(330~295Ma)集中爆发成矿的产物。古亚洲洋西段,沿我国中天山—伊犁南缘—吉尔吉斯北天山—中哈萨克斯坦—科克切塔夫至成吉思线性展布的古生代岩浆弧与哈萨克斯坦山弯构造共同制约了斑岩成矿作用;增生造山向山弯构造的转换阶段为斑岩集中成矿期。蒙古斑岩成矿省亦具新太古代—早古元古代结晶基底;斑岩成矿作用主要发生在泥盆纪(~370Ma)和三叠纪(~240Ma)两个时期,为图瓦-蒙古山弯构造演化过程中两个局部时段的突发成矿;早期成矿事件与古亚洲洋体系向南戈壁微地块下的俯冲增生造山有关,晚期成矿可能是蒙古—鄂霍茨克洋俯冲作用的结果。中国东北斑岩成矿省广泛发育新元古代结晶基底和泛非事件岩石学记录;奥陶纪(482~440Ma)斑岩成矿受控于古亚洲洋早古生代时期俯冲增生作用;而中生代斑岩钼集中爆发成矿则分别受控于古亚洲洋体系后碰撞(~250Ma)、蒙古—鄂霍茨克洋体系同俯冲(248~204Ma)、古太平洋体系同俯冲(195~145Ma)及中国东部岩石圈减薄事件(145~106Ma)不同地球动力学体制。成矿流体方面总体而论,中亚斑岩型矿床热液蚀变遵循经典Lowell and Guibert模式,高氧化性岩浆流体有效出溶造就了大型-超大型斑岩矿床。中亚成矿域斑岩铜矿的成矿斑岩岩石类型与环太平洋域成矿斑岩类似,以钙碱性和高钾钙碱性成分为主,最常见的是石英二长闪长岩、二长花岗岩、花岗闪长岩和花岗岩。成钼矿斑岩比成铜(-金-钼)斑岩更偏酸性,具更高SiO2含量。部分斑岩具埃达克质岩微量元素地球化学特征,另一部分斑岩却有类似正常弧火山岩的特征。虽然现有弧环境斑岩岩浆产生的‘MASH’和‘板片熔融’模型以及‘后碰撞拆沉与新生基性下地壳熔融’模型能够解释中亚成矿域部分斑岩铜矿床成矿的深部机制,但本文新提出‘残余洋中脊俯冲+预富集基性下地壳熔融’模型解释哈萨克斯坦成矿省巴尔喀什—西准噶尔成矿带斑岩铜大规模成矿的深部机制。中亚域斑岩钼成矿与古老地壳或古老岩石圈地幔的熔融无关,而与新生地壳熔融产生长英质岩浆的深部事件存在直接成因联系。西段哈萨克斯坦省新生地壳由古生代古亚洲洋演化过程中弧增生事件形成,而东段中国东北成矿省新生地壳则是新元古代与Rodinia超大陆相关聚合和裂解事件造就的。"新生下地壳部分熔融成钼"模型突破了钼成矿与古老地壳熔融有关的传统认识,能很好地解释全球最大的中国东北钼成矿省的成矿深部动力学机制。 相似文献
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新疆北部斑岩铜矿成矿规律及找矿方向 总被引：5，自引：1，他引：5
新疆北部斑岩铜矿受中亚造山带早古生代固结的哈萨克斯坦—准噶尔板块在华力西期稳定化作用影响，主要形成于华力西中-晚期后造山期挤压向伸展的转换阶段，多数斑岩铜矿带围绕准噶尔板块边缘，分布于板块、陆块边缘造山带中，以及伊犁陆块内部裂谷和觉罗塔格裂陷槽中，几乎均表现出铜（金）-钼矿化特征，并构成了与构造环境有关的斑岩铜钼矿-韧性剪切带型金矿-岩浆岩型铜镍矿成矿系统和与结晶基底建造有关的斑岩铜钼矿-矽卡岩型铜多金属矿-脉状多金属矿成矿系统。 相似文献
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青海省东昆仑地区晚古生代—早中生代火山活动与区域构造演化 总被引：43，自引：1，他引：42
从沉积建造分析入手,通过对区内晚古生代—早中生代火山岩组合的构造属性识别,认为区内晚古生代—早中生代构造演化是一个连续的过程,它奠定了该区的基本构造格局,也是金与铜多金属矿产的主要成矿时期;晚古生代—早中生代发育的双岩浆弧是在同一动力学机制下不同阶段形成的造山岩浆弧：陆缘的钙碱性岩浆弧和陆内的高钾钙碱性岩浆弧。晚古生代—早中生代构造岩浆旋回可以划分为２个阶段,早期的俯冲造山阶段形成了与蛇绿岩有关的火山岩类和弧火成岩类,晚期的大洋闭合和碰撞造山阶段则形成了钾玄岩系列火山岩。 相似文献
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哈萨克斯坦阿克斗卡超大型斑岩型铜矿田地质特征与成矿模式 总被引：4，自引：1，他引：3
中亚成矿域巴尔喀什成矿带阿克斗卡矿田主要由阿克斗卡、艾达里和库兹尔基亚等矿床组成, 是发育在火山岛弧环境的典型斑岩型Cu-Mo-Au矿床群, 其中阿克斗卡为超大型斑岩铜矿。斑岩型铜成矿作用发生在晚古生代哈萨克马蹄形构造形成过程中, 成矿构造背景为乌拉尔-天山断裂系统的大型左行走滑作用和大陆地壳侧向增生过程, 具有典型的斑岩铜矿围岩蚀变和矿石矿物分带特征; 成矿作用受东西向、北东东向和北西西向断裂控制, 主要与早期碱性阶段的硅化蚀变有关, 酸性蚀变阶段发生了再矿化与富集成矿作用; 据含矿花岗闪长岩中锆石SHRIMP定年本文给出主要成矿时代为327.5 ± 1.9 Ma (早石炭世晚期), 成矿模式为"花岗闪长岩"型, 属于浅成斑岩铜矿成矿系统。 相似文献
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内蒙古东乌旗狠麦温都尔锌铜多金属矿床位于大兴安岭-东蒙晚古生代-中生代铜、铁、铅、锌、银、锡、钼、金成矿带中西段。成矿受古生代中亚造山与中生代火山岩浆活动双重影响,成矿背景复杂。矿床的主要含矿围岩为早二叠世宝力高庙组的一套火山碎屑岩,与成矿关系密切的岩体为燕山期花岗斑岩。矿体主要赋存于花岗斑岩与地层接触带外带的断裂破碎蚀变带中。矿体受构造控制,呈NEE向(70°±)展布。矿体的矿化类型主要为细脉状和浸染状,局部呈团块状。成矿元素主要为Zn,伴生Pb和Ag;Cu局部形成单独的矿体。成矿整体受区域构造演化影响,经历了晚古生代火山活动(含矿建造沉积、形成)-中生代岩体侵位-矿化形成的过程。 相似文献
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矿床是大地构造演化的重要指示标志,矿床特征和时空分布格局为重建东天山地区大地构造演化提供了新的制约。研究表明,夹于吐哈地块和中天山地块之间的东天山古生代造山带,在空间上可分为吐哈盆地南缘铜矿带(北带)、康古尔金矿带(中带)和阿齐山—雅满苏铁(铜)-银多金属矿带(南带)3个不同的构造-地层(岩浆)-成矿带。在时间上东天山造山带具有明显的三阶段演化性:(1)吐哈盆地南缘奥陶—泥盆纪为活动大陆边缘,形成了包括VMS型铜锌矿床和斑岩型铜矿床在内的古陆缘成矿系统;晚泥盆世末—早石炭世初古洋壳向北俯冲关闭,中天山地块增生拼贴到吐哈地块(属哈萨克斯坦—准噶尔板块组成部分)南缘。(2)早石炭世(维宪期)沿康古尔缝合带再次拉张,形成石炭纪裂陷槽火山-沉积岩系及相应的层控成矿系统(VMS型铜锌矿床、火山岩型铁(铜)矿床、自然铜矿床),裂陷槽封闭过程中发育了夕卡岩型银多金属矿床。(3)早二叠世形成与幔源岩浆底侵作用有关、跨构造单元发育的铜镍硫化物成矿系统和与剪切活动有关的金矿床。依据上述认识,对东天山地区的矿产勘查提出了新建议。 相似文献
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新疆哈密南部发现的土屋、延东大型斑岩铜(钼)矿床,构成了东天山斑岩铜矿带。其中成矿的斜长花岗斑岩同位素年龄为369～356 Ma(Rb-Sr等时线法和单颗粒锆石U-Pb法),辉钼矿的同位素年龄为320 Ma(Re-Os等时线法),蚀变岩的同位素年龄为341～310Ma,含矿围岩由粗面质玄武岩到粗安岩,可能属于泥盆纪(416Ma,Sm-Nd法;>356 Ma、390 Ma、440 Ma,单颗粒锆石U-Pb法)。矿床成因归属为岛弧火山—深成作用产物。斑岩铜矿带的南部为著名的康古尔塔格金矿带,再往南为星星峡银矿带。这些造山带矿床组合由北而南构成斑岩型铜(钽)矿带→韧性剪切带型和浅成热液型金矿带→浅成热液型(构造蚀变带型)钼矿带,显示了构造岩浆是由北而南下插的,岩浆侵位时间北老南新,花岗质岩浆源区的部分熔融深度由北而南加深。反映壳幔演化的东天山构造岩浆作用从370 Ma到240 Ma、从北部的哈尔里克和康古尔塔格到南部的中天山,似乎存在一个连续的花岗质岩浆演化带,丝毫看不到深部作用过程由于古生代东天山数度拉张沦为海槽而被中断的迹象。基于以上主要证据,本文综合讨论了东天山斑岩型铜矿、韧性剪切带型金矿和构造蚀变带型银矿的形成机制及其大地构造格局,建立了东天山造山带的成矿模型,为今后找矿开辟了新方向。 相似文献
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《International Geology Review》2012,54(7):801-822
The Central Tianshan terrane (CTT) is part of the southwestern margin of the Central Asian Orogenic Belt (CAOB). Since the collision between CTT and Tarim block marks the termination of the South Tianshan Ocean in the southwestern corner of the CAOB, the CTT is regarded as a key area for understanding the tectonic evolution of the CAOB. The Airikenqiken granitic pluton is located ~30 km to the northwest of Baluntai town in the eastern part of CTT. Here we report a zircon LA-ICP-MS U–Pb age of 320.1 ± 3.3 Ma for the granite. Geochemically, the pluton is characterized by a high concentration of SiO2 (71.01–73.58 wt.%) and relatively low contents of MgO (0.28–0.5 wt.%), Cr (1–10 ppm), and Ni (~2 ppm). The rocks show enrichment of large ion lithophile elements (LILEs) and significantly negative Nb, Ta, Ti, and P anomalies. Light rare earth element (LREE) enrichment and slightly negative Eu anomalies are also displayed. Zircon εHf(t) values at ~320 Ma range from – 1.1 to +12.2. Our data suggest that the parental magma of the pluton was generated by partial melting of a thickened garnet-bearing, amphibolite facies lower crust. The magma was contaminated by ancient crustal components en route to the shallow crust. Together with the information from previous studies on the Central and South Tianshan Mountains, we propose that the Airikenqiken granite formed in a post-collisional setting and that the late Palaeozoic continental growth of CTT involved the input of juvenile components. 相似文献
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中元古代时期,神农架位于华南古陆,与澳大利亚古陆及西伯利亚古陆相邻,同处于罗迪尼亚超级大陆（Rodinia supercontinent）北部。其沿海的叠层石组合与澳大利亚古陆及西伯利亚古陆沿海的叠层石组合相似,显示了炎热气候下的碳酸盐岩台地潮坪浅水环境特征。常见的叠层石形态类型包括穹状、柱状、层柱状和层状等。主要有神农架大圆顶叠层石（Megadomia shennongjiaensis）、加尔加诺锥叠层石（Conophyton garganicum）、树桩圆柱叠层石（Colonnella cormosa）、简单包心菜叠层石（Cryptozoon haplum）、喀什喀什叠层石（Kussiella kussiensis）、圆柱朱鲁莎叠层石（Jurusania cylindrica）、地窖印卓尔叠层石（Inzeria intia）、瘤通古斯叠层石（Tungussia nodosa）、贝加尔贝加尔叠层石（Baicalia baicalica）、育卡贝加尔叠层石（Baicalia unca）、奥姆泰奥姆泰叠层石（Omachtenia omachtensis）和波层叠层石（Stratifera undata）等。 相似文献
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Kiymet DENIZ 《《地质学报》英文版》2022,96(3):844-857
This study focuses on the nature of giant micas occurring at the contact between the ?zvatan (foid-bearing) syenites and the metamorphic basement in Central Anatolia. The studied micas are dark greenish-black in color and crystallized within vein shape like bodies as a narrow lens. The origin and processes responsible for the formation of these independent crystals of the giant micas were investigated by mineralogical, petrographical and geochemical analyses with the use of Confocal Raman Spectroscopy (CRS), Fourier Transform Infrared (FTIR) Spectroscopy, X-Ray Diffraction (XRD), Polarized Energy Dispersive X-Ray Fluorescence Spectrometer (PED-XRF) and Electron Probe Micro Analysis (EPMA). According to XRD, CRS, FTIR and EPMA data, the giant micas are phlogopite. EPMA results reveal that studied mica minerals represent the products of re-equilibrated primary mica characterized by high MgO and FeO and low Al2O3 and TiO2 contents. The trace element concentrations of the giant micas display similar patterns with the upper crust. The giant micas are crystallized within small cubicles from an alkaline magma and their composition is possibly modified by a mixing event between the crust- and mantle-derived magmas and contaminated at varying extent by the basement metamorphic rocks. 相似文献
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The Irruputuncu is an active volcano located in northern Chile within the Central Andean Volcanic Zone (CAVZ) and that has produced andesitic to trachy-andesitic magmas over the last ∼258 ± 49 ka. We report petrographical and geochemical data, new geochronological ages and for the first time a detailed geological map representing the eruptive products generated by the Irruputuncu volcano. The detailed study on the volcanic products allows us to establish a temporal evolution of the edifice. We propose that the Irruputuncu volcanic history can be divided in two stages, both dominated by effusive activity: Irruputuncu I and II. The oldest identified products that mark the beginning of Irruputuncu I are small-volume pyroclastic flow deposits generated during an explosive phase that may have been triggered by magma injection as suggested by mingling features in the clasts. This event was followed by generation of large lava flows and the edifice grew until destabilization of its SW flank through the generation of a debris avalanche, which ended Irruputuncu I. New effusive activity generated lavas flows to the NW at the beginning of Irruputuncu II. In the meantime, lava domes that grew in the summit were destabilized, as shown by two well-preserved block-and-ash flow deposits. The first phase of dome collapse, in particular, generated highly mobile pyroclastic flows that propagated up to ∼8 km from their source on gentle slopes as low as 11° in distal areas. The actual activity is characterized by deposition of sulfur and permanent gas emissions, producing a gas plume that reaches 200 m above the crater. The maximum volume of this volcanic system is of ∼4 km3, being one of the smallest active volcano of Central Andes. 相似文献
15.
黔中早二叠世茅口晚期断裂陆缘层序地层分析 总被引：4，自引：0，他引：4
黔中早二叠世晚期发育变异多姿的硅质岩－碳酸盐岩和火山岩，笔者通过大地构造学、火山岩岩石学和岩石地球化学、层序地层学的综合分析认为，与一般的被动大陆边缘不同，该区这种断裂大陆边缘的层序地层特征主要依据纵向上反映海平面变化的岩性突变来识别，而岩性突变又是构造变动的反映。据此，将该区茅口组二段划分为一个准层序组和两个准层序，每个准层序以突变最大海泛面为基础，包含了凝缩层和加积高位体系域；横向上解释为破裂碳酸盐台地型层序地层格架，即把构造作用与层序地层格架的形成以及沉积体系的分异统一起来，提出了断裂陆缘层序层分析的实例。 相似文献
16.
Natural hazards in Central Java Province,Indonesia: an overview 总被引：2，自引：0，他引：2
Muh Aris Marfai Lorenz King Lalan Prasad Singh Djati Mardiatno Junun Sartohadi Danang Sri Hadmoko Anggraini Dewi 《Environmental Geology》2008,56(2):335-351
Central Java Province, Indonesia, suffers from natural hazard processes such as land subsidence, coastal inundation, flood,
volcanic eruption, earthquake, tsunami, and landslide. The occurrence of each kind of natural hazard is varied according to
the intensity of geo-processes. It is necessary to learn from the historical record of coastal inundation, flood, volcanic
eruption, earthquake, tsunami, and landslide hazards in Central Java Province to address issues of comprehensive hazard mitigation
and management action. Through the understanding about the nature and spatial distribution of natural hazards, treatments
can be done to reduce the risks. This paper presents the natural hazard phenomena in Central Java Province and provides critical
information for hazard mitigation and reduction. 相似文献
17.
川中安平店-高石梯构造震旦系灯影组流体充注特征及油气成藏过程 总被引：1，自引：0，他引：1
川中地区震旦系灯影组储层时代老、埋藏深,经历了多期构造运动和成藏历史。岩芯观察和显微薄片观察结果表明,震旦系灯影组储层经历了六期流体充注,分别是第一世代沥青→第二世代白云石→第三世代粗晶-巨晶白云石→第四世代粗晶-巨晶白云石→第五世代沥青→第六世代方解石/石英,每期矿物中对应的流体包裹体特征记录了震旦系从早期形成的古油藏被破坏→古油气藏再形成→油裂解气和古气藏形成→水溶气形成→现今气藏形成的成藏事件和完整的成藏过程。第二世代-第四世代矿物形成于深埋过程中,是古油气藏形成期的产物,矿物的Sr、C、O稳定同位素表明向震旦系灯影组充注的流体主要是外源流体,具有从深部向浅部流动运移的特征;第六世代矿物所记录的水溶气的形成,也是震旦系最重要的成藏事件;现今的震旦系灯影组气藏主要是晚白垩世以来的构造隆升导致的水溶气脱溶聚集以及油气藏调整和改造的结果。 相似文献
18.
《International Geology Review》2012,54(14):1803-1821
ABSTRACTIn the Central Anatolia, the style of neotectonic regime governing the region has been a controversial issue. A tectonic study was carried out in order to contribute to this issue and better understand the neotectonic stress distribution and style of deformation in the west-southwest of the Konya region. From Middle Miocene to Recent time, Konya region was part of the Central Anatolia extensional province. The present-day topography in the west-southwestern part of Konya is characterized by alternating elongate grabens and horsts trending E-W and NW-SE. The grabens were developed upon low-grade metamorphic rocks of Palaeozoic and Mesozoic ages and ophiolite slabs of possibly Late Cretaceous age. The evolutionary history of grabens is episodic as evidenced by two graben infills; older and younger graben infills separated by an angular unconformity. The older infill consists of fluviolacustrine sequence intercalated with calc-alkaline lavas and pyroclastic rocks. This infill is folded; thrust faulted and Middle Miocene-Early Pliocene in age. The younger and undeformed basin fill comprises mainly of Plio-Quaternary conglomerates, sandstone-mudstone alternations of alluvial fan and recent basin floor deposits. Three major tectonic phases were differentiated based on the detailed mapping, morphological features and kinematic analysis. Approximately N-S trending extension began in the Middle Miocene-Early Pliocene in the region with the formation of E-W and NW-SE-trending grabens. Following NE-SW-directed compression which deformed the older basin fill deposits by folding and thrusting, a second period of ENE-WSW-trending extension began in the late Pliocene and continued to the present. The west-southwestern margin of the Konya depression is bounded by the Konya Fault Zone. It is an oblique-slip normal fault with a minor dextral strike-slip component and exhibits well-preserved fault slickensides and slickenlines. Recent seismicity and fault-related morphological features reveal that the Konya Fault Zone is an active neotectonic structure. 相似文献
19.
The Triassic granitoids in Central Tianshan play a key role in determining the petrogenesis and tectonic evolution on the southern margin of the Central Asian orogenic belt. In this study, we present SHRIMP zircon U-Pb ages, Hf isotopic and geochemical data on the Xingxingxia biotite granite, amazonite granite and granitic pegmatite in Central Tianshan, NW China. Zircon U-Pb dating yielded formation ages of 242 Ma for the biotite granite and 240 Ma for the amazonite granite. These granitoid rocks have high K2O with low MgO and CaO contents. They are enriched in Nb, Ta, Hf and Y, while being depleted in Ba and Sr, showing flat HREE patterns and negative Eu anomalies. They have typical A-type granite geochemical signatures with high Ga/Al (8–13) and TFeO/(TFeO + MgO) ratios, showing an A2 affinity for biotite granite and an A1 affinity for amazonite granite and granitic pegmatite. Zircon εHf(t) values of the granitoids are 0.45–2.66, with Hf model ages of 0.99–1.17 Ga. This suggests that these A-type granites originated from partial melting of the lower crust. We propose that Xingxingxia Triassic A-type granites formed under lithospheric extension from post-orogenic to anorogenic intraplate settings and NE-trending regional strike-slip fault-controlled magma emplacement in the upper crust. 相似文献