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以大量国内外脉状金矿成矿流体研究资料为基础，本文介绍并综合评述了成矿流体成分、性质和来源三方面的研究现状与进展，指出全球性脉状金矿成矿流体成分惊人的一致性可能会对脉状金矿成矿流体来源和成矿机制的认识产生深刻的影响，把相同构造背景下一组脉状金矿床作为一个统一的群体去研究它们的形成、演化可能是脉状金矿成因研究的一个趋势。 相似文献
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以大量国内外脉状金矿成矿流体研究资料为基础，本文介绍并综合评述了成矿流体成分，性质和来源三方面的研究现状与进展，指出全球性脉状金矿成矿流体成分惊人的一致性可能会以地脉状金矿成矿流体来源和成在放机制的认识产生深刻的影响，把相同构造背景下一组脉状金矿床作为一个统一的群体去研究它们的形成，演化可能是脉状金矿成因研究的一个趋势。 相似文献
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甘肃阳山超大型热液金矿床的成矿特征 总被引：5，自引：2，他引：5
从阳山超大型金矿床的区域构造演化发展背景、成矿地质地球化学等特征进行的研究与分析表明,它是形成、产出在中新生代活化造山带、地壳高位浅成的中低温热液型超大型金矿床。从大地构造成矿学的研究途径,对其成矿流体与成矿物质的源区类型、形成与演化的构造环境、成矿作用的地质成因类型、成矿流体传输与聚集的构造系统等方面的初步研究表明成矿流体是变质与非变质的复杂混合体系,主要由基底、盖层中的构造热动力区域变质流体+重熔花岗岩浆热变质流体+岩浆热液等,组成多成因类型混合成矿流体,并受到同生水、大气降水的混染。因此,阳山金矿主要是由混合型变质成矿流体与岩浆热液成矿流体叠加形成,具有多因复成成矿特征的超大型中低温热液金矿床。 相似文献
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河南西峡石板沟金矿成矿流体地球化学及矿床成因讨论 总被引：5，自引：2，他引：3
石板沟金矿是近年在豫西南发现的一个剪切带容矿的脉状金矿。根据流体包裹体地球化学研究,分析了矿床成矿流体地球化学特征,讨论了金的沉淀机制和矿床成因。构造蚀变岩型金矿的形成主要与热液蚀变作用有关,石英脉型金矿的形成,则可能主要与岩浆热液与变质热液的混合作用有关。矿质主要源自晋宁期岩浆岩,成矿流体和热能主要来自海西期花岗岩。矿床为剪切带容矿的中低温热液金矿床。 相似文献
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华北克拉通南缘在中生代发生了大规模的成矿作用,主要的矿床类型有脉状金矿床(石英脉型、构造蚀变岩型)、斑岩型钼矿床、脉状银铅锌矿床.对于这些矿床的成因和成矿动力学背景,目前还存在不少争议.但近年来越来越多的成矿年代学证据表明,这些矿床均主要形成于早白垩世,且与区域上广泛发育的岩浆活动具有高度的时空一致性.在归纳总结华北克拉通南缘主要矿床类型地质特征和时空分布的基础上,简述各类矿床的成矿物质来源以及它们之间的成因联系,指出这些不同类型的矿床组成了一个巨型的岩浆-热液成矿系统.华北克拉通南缘成矿作用与其邻近的东秦岭-大别成矿带的成矿作用具有一致性,均受中国东部早白垩世大规模伸展作用控制,是统一的地球动力学背景下的产物.结合地球物理的资料认为,早白垩世岩石圈伸展及其导致的岩浆作用最可能与晚中生代古太平洋板块向东亚大陆边缘俯冲作用有关.上涌的岩浆热液在合适的构造体制下,与上地壳的岩石和流体发生交代和流体混合,最终在浅部形成大规模的岩浆-热液成矿系统. 相似文献
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在系统研究内蒙后二道沟铜金矿床地质特征、矿体地质特征、地球物理特征及地球化学特征的基础上,将地质、物探及化探等数据进行系统关联,探讨各类信息之间的相关关系,从而构建了以"有利成矿地质条件+Au、Cu、Pb、Zn、As等指示元素的综合异常+低阻、高极化、高磁"为标志的综合信息找矿模型,综合异常区域可能是矿(化)体的赋存位置,其激电测深低视电阻率300Ω·m、高极化率3.0%、高磁异常300 nT。初步分析成矿构造背景及成矿三要素(热能、成矿流体、成矿物质)来源,并建立了矿床成因模式,认为矿床类型有矽卡岩型铜金铅锌多金属矿床、构造破碎带型铜金多金属矿床和石英脉型金矿床。 相似文献
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花岗岩成矿的几个判别标志 总被引：14，自引：1，他引：14
花岗岩具成矿专属性。在不同大地构造背景及造山作用不同阶段，不同源岩的部分熔融形成类型、矿物学和地球化学成分、成因、分异演化均不同的花岗岩类，出现不同程度的环带构造、断裂构造和交代作用现象，它们均与相关的成矿元素组合具有一定的相关关系，对花岗岩成矿起关键性的控制作用。本文归纳总结了花岗岩成矿的几个判别标志：大地构造背景、花岗岩的环带构造、成矿流体可迁移性及自交代作用、矿物学和地球化学特征。 相似文献
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华北克拉通南缘在中生代发生了大规模的成矿作用,主要的矿床类型有脉状金矿床（石英脉型、构造蚀变岩型）、斑岩型钼矿床、脉状银铅锌矿床.对于这些矿床的成因和成矿动力学背景,目前还存在不少争议.但近年来越来越多的成矿年代学证据表明,这些矿床均主要形成于早白垩世,且与区域上广泛发育的岩浆活动具有高度的时空一致性.在归纳总结华北克拉通南缘主要矿床类型地质特征和时空分布的基础上,简述各类矿床的成矿物质来源以及它们之间的成因联系,指出这些不同类型的矿床组成了一个巨型的岩浆-热液成矿系统.华北克拉通南缘成矿作用与其邻近的东秦岭-大别成矿带的成矿作用具有一致性,均受中国东部早白垩世大规模伸展作用控制,是统一的地球动力学背景下的产物.结合地球物理的资料认为,早白垩世岩石圈伸展及其导致的岩浆作用最可能与晚中生代古太平洋板块向东亚大陆边缘俯冲作用有关.上涌的岩浆热液在合适的构造体制下,与上地壳的岩石和流体发生交代和流体混合,最终在浅部形成大规模的岩浆-热液成矿系统. 相似文献
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基于目前代表性金矿成因模式的局限性,以吉林夹皮沟金矿为例把金矿的形成总结为定位、流体、物源、封闭、加热和构造成矿六大系统,建立新的幔-壳多层循环体成因模式:1)以幔源流体、岩浆热液和浅-表部水来源为主,按深、中、浅构成三个层次循环体;2)金质来自多层循环流体对多类型围岩的萃取、沟通混合及多次构造应力共同作用的结果;3)断层泥、迭瓦状构造地质体等可作为成矿封闭屏障;4)中生代(隐伏)花岗岩和各类型脉岩为主要加热热源;5)矿带座落在韧性构造超壳断裂之上及附近,而矿体却主要赋存在脆性构造内,主成矿时代为燕山期,整体受构造-成矿系统控制.该模式对燕山期花岗岩中金矿是一种检验,对其它变质岩区金矿则是一种启迪. 相似文献
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胶东地区破碎带蚀变岩型金矿时代的测定及其地质意义 总被引：30，自引：4，他引：26
通过对胶东半岛西北部超大型破碎带蚀变岩型金矿 -新城金矿的强烈热液交代成因黄铁绢英岩 Rb- Sr等时线法测年 ,获得 116 .6± 5 .3Ma成矿年龄。结合本区焦家、仓上等大型 -超大型金矿蚀变矿物、石英流体包裹体的 Rb- Sr等时线年龄、K- Ar年龄 (10 5± 7Ma;10 6± 2 Ma;113.5± 0 .6 Ma)等前人成果 ,确定胶东半岛西北部破碎带蚀变岩型金矿成矿时代主要集中在 10 0～ 117Ma。与围岩花岗岩、花岗闪长岩的成岩年龄 (16 0～ 15 0 Ma;130～ 12 6 Ma)存在着近 10 Ma的时差 ,并根据(87Sr/ 86 Sr) i比值以及已有的 C、H、O稳定同位素资料表明 ,即使成矿物质部分来源于围岩花岗岩类 ,但成矿作用与岩浆活动无明显的成因关系 ,而是深部循环的大气降水或幔源 C- H - O流体参与成矿作用的结果 相似文献
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Composition and evolution of fluids depositing tin and tungsten ores in Kibaran quartz vein deposits allow the modelling of devolatizing evolved granites as their source at depth. Fluids forming gold quartz veins and breccias are different from the first, especially by showing characteristics of a high-pressure environment. All deposits are controlled by compressional deformation whose fading phases affect earlier formed veins. These findings lead to the conclusion that both anatectic melting resulting in intrusion of fertile granites, and the generation of fluids forming gold deposits are the final consequence of deep crustal metamorphism. The latter was caused by crustal thickening immediately preceding the metallogenetic climax. 相似文献
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胶东地区重要金矿床是以硫化物石英脉为主的和以硫化物蚀变岩为主的两类,对它们的成矿流体组分和温压条件等方面的研究表明,其含矿流体均起源于下地壳,为玄武岩浆底热提供热( 部分流体)作用形成;其含矿流体上升演化成矿过程表现:以硫化物石英脉为主的金矿床是在相对稳定的环境下含矿流体降温降压结晶分异成矿,而以硫化物蚀变岩为主的金矿床则是流体发生沸腾作用成矿;成矿过程的温-压(能量)演化轨迹显示,大型矿床具有完整的P-T演化轨迹或具有沸腾特征,相对小的矿床一般不具完整的P-T轨迹.这项研究对深入认识胶东金矿成因及成矿规律具有重要的价值. 相似文献
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Su Xiaosi 《吉林大学学报(地球科学版)》1994,(1)
在综述了脉岩与热液型脉状金矿关系的基础上，认为中基性脉岩、煌斑岩脉不仅在空间上与脉状金矿相伴生，形成时间祁近，而且在物源和成因上有着密切的关联。脉岩是脉状金矿床成因系列的组成部分。据此提出中基性岩浆在某种动力作用下，诱导上覆花岗质岩石（包括古老变质岩）熔融，并发生混染，在地壳脉动作用下，脉岩与含矿流体多期次多阶段侵位，在相应的部位形成脉岩与矿脉共存的金矿区带。 相似文献
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The dilemma of the Jiaodong gold deposits: Are they unique? 总被引：2，自引：0，他引：2
The ca. 126e120 Ma Au deposits of the Jiaodong Peninsula, eastern China, define the country＇s largest gold province with an overall endowment estimated as＆gt;3000 t Au. The vein and disseminated ores are hosted by NE-to NNE-trending brittle normal faults that parallel the margins of ca. 165e150 Ma, deeply emplaced, lower crustal melt granites. The deposits are sited along the faults for many tens of kilometers and the larger orebodies are associated with dilatational jogs. Country rocks to the granites are Pre-cambrian high-grade metamorphic rocks located on both sides of a Triassic suture between the North and South China blocks. During early Mesozoic convergent deformation, the ore-hosting structures developed as ductile thrust faults that were subsequently reactivated during Early Cretaceous ＂Yan-shanian＂intracontinental extensional deformation and associated gold formation. 〈br〉 Classification of the gold deposits remains problematic. Many features resemble those typical of orogenic Au including the linear structural distribution of the deposits, mineralization style, ore and alteration assemblages, and ore fluid chemistry. However, Phanerozoic orogenic Au deposits are formed by prograde metamorphism of accreted oceanic rocks in Cordilleran-style orogens. The Jiaodong de-posits, in contrast, formed within two Precambrian blocks approximately 2 billion years after devolati-lization of the country rocks, and thus require a model that involves alternative fluid and metal sources for the ores. A widespread suite of ca. 130e123 Ma granodiorites overlaps temporally with the ores, but shows a poor spatial association with the deposits. Furthermore, the deposit distribution and mineral-ization style is atypical of ores formed from nearby magmas. The ore concentration requires fluid focusing during some type of sub-crustal thermal event, which could be broadly related to a combination of coeval lithospheric thinning, asthenospheric upwelling, paleo-Pacific plate subduction, and seismicity along the continental-scale Tan-Lu fault. Possible ore genesis scenarios include those where ore fluids were produced directly by the metamorphism of oceanic lithosphere and overlying sediment on the subducting paleo-Pacific slab, or by devolatilization of an enriched mantle wedge above the slab. Both the sulfur and gold could be sourced from either the oceanic sediments or the serpentinized mantle. A better understanding of the architecture of the paleo-Pacific slab during Early Cretaceous below the eastern margin of China is essential to determination of the validity of possible models. 相似文献
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东秦岭两类花岗岩与两个金矿系列 总被引：14，自引：3，他引：14
本文根据东秦岭地区花岗岩金矿的特征，全面地探讨了花岗岩与金矿化的关系，将东秦岭地区与花岩有关的金矿床分为深源浅成型花岗岩金矿系列和浅源深成型花岗岩金矿系列。不同成因系列的花岗岩与金矿的关系完全不同。文中还简要地阐述了与两个系列金矿有关的花岗岩的地花岗岩的地质地球化学特征和秦岭造山带的构造演化。 相似文献
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The magma–ore deposit relationship of most low-sulfidation epithermal ore deposits is still unclear, partly because many stable isotopic studies of such deposits have indicated the predominance of meteoric waters within hydrothermal fluids. However, it is certainly true that hydrothermal systems are ultimately driven by magmatic intrusions, and epithermal gold deposits might therefore be produced by magmatic activity even in deposits having has no obvious links to a magma. We re-examine the genesis of two typical low-sulfidation epithermal gold deposits, the Kushikino and Hishikari deposits, using structural simulations and isotope data.Many epithermal gold deposits including the Kushikino and Hishikari deposits have been discovered in Kyushu, southwestern Japan. The Kushikino deposit comprises fissure-filling veins within Neogene andesitic volcanics that overlie unconformably Cretaceous sedimentary basement. The veins consist of gold- and silver-bearing quartz and calcite with minor amounts of adularia, sericite and sulfides. Although carbon and oxygen isotopic data for the veins indicate a meteoric origin of the ore fluid, finite element simulations suggest that the vein system might have formed in direct response to magma intrusion. In particular, geophysical data suggest that intruding magma has uplifted the basement rocks, thereby producing fractures and veins and a positive Bouguer anomaly, and providing the heat necessary to drive an ore-forming hydrothermal system.The second component of this study has been to investigate the nature and evolution of the Kushikino and Hishikari epithermal systems. Isotope data document the geochemical evolution of the hydrothermal fluids. We conclude that the existence of sedimentary basement rocks at depth might have affected the strontium and carbon isotopic ratios of the Kushikino and Hishikari ore fluids. The 87Sr/86Sr ratios and δ13C–δ18O trend reveal that major ore veins in the Hishikari deposit can be distinguished from shallow barren veins. It was suggested isotopically that fluids responsible for the barren veins in nearby shallow and barren circulation systems were only controlled by the shallow host rocks. Such multi-isotope systematics provide a powerful tool with which to determine the center of hydrothermal activity and thereby document the evolution of hydrothermal fluids. 相似文献
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《Ore Geology Reviews》2009,35(4):597-609
The magma–ore deposit relationship of most low-sulfidation epithermal ore deposits is still unclear, partly because many stable isotopic studies of such deposits have indicated the predominance of meteoric waters within hydrothermal fluids. However, it is certainly true that hydrothermal systems are ultimately driven by magmatic intrusions, and epithermal gold deposits might therefore be produced by magmatic activity even in deposits having has no obvious links to a magma. We re-examine the genesis of two typical low-sulfidation epithermal gold deposits, the Kushikino and Hishikari deposits, using structural simulations and isotope data.Many epithermal gold deposits including the Kushikino and Hishikari deposits have been discovered in Kyushu, southwestern Japan. The Kushikino deposit comprises fissure-filling veins within Neogene andesitic volcanics that overlie unconformably Cretaceous sedimentary basement. The veins consist of gold- and silver-bearing quartz and calcite with minor amounts of adularia, sericite and sulfides. Although carbon and oxygen isotopic data for the veins indicate a meteoric origin of the ore fluid, finite element simulations suggest that the vein system might have formed in direct response to magma intrusion. In particular, geophysical data suggest that intruding magma has uplifted the basement rocks, thereby producing fractures and veins and a positive Bouguer anomaly, and providing the heat necessary to drive an ore-forming hydrothermal system.The second component of this study has been to investigate the nature and evolution of the Kushikino and Hishikari epithermal systems. Isotope data document the geochemical evolution of the hydrothermal fluids. We conclude that the existence of sedimentary basement rocks at depth might have affected the strontium and carbon isotopic ratios of the Kushikino and Hishikari ore fluids. The 87Sr/86Sr ratios and δ13C–δ18O trend reveal that major ore veins in the Hishikari deposit can be distinguished from shallow barren veins. It was suggested isotopically that fluids responsible for the barren veins in nearby shallow and barren circulation systems were only controlled by the shallow host rocks. Such multi-isotope systematics provide a powerful tool with which to determine the center of hydrothermal activity and thereby document the evolution of hydrothermal fluids. 相似文献