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西秦岭拉尔玛金矿中的生物成矿作用 总被引：2，自引：0，他引：2
位于西秦岭南亚带的拉尔玛金矿赋存于寒武系太阳顶群中,虽然该矿床的矿体分布主要受断裂的控制,但是,本区区域地层的含金性、岩(矿)石的硫同位素、碳同位素、铅同位素、矿物流体包裹体的氢氧同位素组成、稀土元素组成和黄铁矿成因 相似文献
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西藏墨竹工卡县洞中拉铅锌矿床S、Pb同位素组成及成矿物质来源 总被引：1，自引：0，他引：1
为了探讨西藏墨竹工卡县洞中拉铅锌矿的成矿物质来源,研究矿床成矿机制,对该矿床的矿石样品进行了硫和铅同位素分析,并对其变化规律和成因意义进行讨论。研究结果表明,6件金属硫化物样品(闪锌矿、黄铜矿、方铅矿)的δ34S值变化于2.2‰～4.8‰之间,显示硫同位素组成比较稳定。根据共生硫化物对所确定的温度,该矿床属中低温热液矿床。6件金属硫化物样品206Pb/204Pb、207Pb/204Pb和208Pb/204Pb变化范围分别为18.628 0～18.629 6、15.698 0～15.699 9、39.077 5～39.082 4,平均值分别为18.628 70、15.699 02和39.079 37。硫和铅同位素研究结果表明,洞中拉铅锌矿床的硫主要来自沉积围岩,主要为无机还原成因,有少量硫来自本地区燕山晚期花岗岩;洞中拉铅锌矿床矿石铅主要来自上地壳物质。 相似文献
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西成地区铅-锌矿、金矿硫铅同位素特征及成矿关系的研究 总被引：5，自引：1，他引：4
甘肃省西成地区分布有多种类型的铅-锌矿和金矿,已探明海底喷流型（SEDEX）铅-锌矿资源量超过1300×10^4t（金属量）。金矿主要分布于盆地中西部泥盆系厚层碎屑岩中．受控于韧性剪切带。对矿床中硫化物硫、铅同位素研究结果表明,西成铅-锌矿田北矿带的后期改造是在相对封闭的环境下实现的、而南矿带铅-锌矿则有部分外来物质的参与,但并未发生明显的分异,同时,两个矿带喷流（气）-沉积过程的不同,这也是导致硫同位素存在差异的重要原因。在印支期的成矿过程中金矿具有明显独立于铅-锌矿的地质特点与硫、铅同位素演化过程,硫主要源自区内的围岩,而铅同位素中则有较多放射性成因铅的加入。 相似文献
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刘屯金矿床为含金硫化物石英脉型,矿体直接围岩为晚太古代混合花岗岩。区域上建平群大营子组为金的矿源层,金成矿与中生代构造岩浆活动密切相关。含金石英脉(矿脉)严格地受近东西向断裂构造控制。据硫同位素组成证明矿石、围岩、中生代侵入岩具有同一性,为幔源硫。氢氧同位素组成则显示了成矿溶液的多成因特征。矿石中铅同位素为古老的铅体系,与中生代岩体的长石铅属同一源地。通过时矿床成因的探讨,认为是"岩浆热源-混合热液"型复成因金矿床,成矿时代为燕山期。 相似文献
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二郎坪群是东秦岭造山带重要的组成部分,其火山建造中广泛发育有火山成因块状硫化物(VMS)矿床.文章总结并分析了南阳盆地东、西两侧二郎坪群中3个典型矿床(刘山岩、水洞岭和上庄坪)的研究资料,把二郎坪群VMS矿床分为3类:Zn-Cu型矿床(刘山岩矿床);Zn-Cu型与Zn-Pb-Cu型矿床(水洞岭矿床);Zn-Pb-Cu型矿床(上庄坪矿床).从刘山岩矿床到水洞岭矿床,再到上庄坪矿床,铜的含量减少,铅的含量增多.二郎坪群VMS矿床矿石富集LREE、Ce负异常及Eu正异常,说明矿床为热液成因.石英和重晶石中流体包裹体的氢氧同位素特征表明,成矿流体主要来自建造水,南阳盆地以西,矿床成矿流体中伴有较多古大气降水.矿石的硫同位素特征说明,二郎坪群VMS矿床中的硫可能为地幔岩浆硫和海水硫的混合硫.围岩与矿石的铅同位素组成基本一致,说明矿石和围岩可能来源于相似的物源区,成矿元素主要来源于地幔或下地壳深源物质,而水洞岭矿床明显有上地壳浅源物质的混染.研究表明,南阳盆地以西的水洞岭和上庄坪矿床可能形成于大陆边缘海环境,盆地规模较小,受陆源物质影响较大;而南阳盆地以东的刘山岩矿床可能形成于远洋盆地,盆地到达成熟阶段.用地震泵模式可解释二郎坪群VMS矿床的成因机制. 相似文献
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宝山铜铅锌多金属矿床是湖南重要的铅锌生产基地。矿床内矽卡岩型铜(钼)矿化受侏罗纪花岗闪长斑岩的控制,而主要的铅锌矿体则产于远离岩体的碳酸盐地层中,且缺乏可靠的矿化年龄限制。为了查明宝山铅锌矿体与花岗闪长斑岩之间的成因关系,文章对宝山花岗岩类中浸染状黄铁矿的硫同位素和钾长石的铅同位素,以及铅锌矿石萤石脉石的流体包裹体进行了测试和研究,并与前人报道的铅锌硫化物矿石的硫、铅同位素进行了对比,尝试为宝山铅锌矿化的物质来源及成因提供依据。研究表明,花岗闪长斑岩中浸染状黄铁矿的δ34S值为+1.5‰~+3.5‰,与铅锌矿石硫化物(方铅矿、闪锌矿及黄铁矿)相一致;同时,花岗岩类中钾长石的铅同位素组成206Pb/204Pb、207Pb/204Pb和208Pb/204Pb分别为18.4789~18.7668、15.6835~15.7220和38.7903~39.1035,具有壳源的特征,且与铅锌矿石硫化物的铅同位素分布范围相吻合。宝山矿床的硫、铅同位素特征表明,花岗闪长斑岩应是铅锌矿化的主要硫源及金属来源。宝山矿床铅锌矿石萤石中的流体包裹体具有低温(130~150℃)、低盐度(8%)的特征,可能是岩浆热液演化到晚期的产物。结合已有的有关资料加以对比和分析,研究认为,宝山铅锌矿床的成矿物质应来源于花岗闪长岩的岩浆期后热液,在热液演化晚期迁移到远端地层中沉淀,形成了宝山的主要铅锌矿体。 相似文献
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西藏蒙亚啊铅锌矿床S、Pb同位素组成及对成矿物质来源的示踪 总被引：11，自引：3，他引：8
西藏蒙亚啊铅锌矿床位于冈底斯成矿带东段,矿体主要赋存于上石炭统—下二叠统来姑组碳酸盐岩内的矽卡岩和矽卡岩化大理岩中,近东西向似层状产出。在分析该矿床成矿地质条件的基础上,系统地研究了矿石硫、铅同位素组成特征,探讨了成矿物质来源。研究表明,矿石硫化物的硫同位素组成变化范围较窄,具塔式分布效应,估算得到成矿热液系统的总硫同位素值3δ4S∑S约为5.2‰,具有岩浆硫的特征;矿石铅同位素组成稳定,为正常普通铅,矿石铅来源于早白垩世上地壳物质部分熔融形成的岩浆。 相似文献
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The Rammelsberg polymetallic massive sulphide deposit was the basis of mining activity for nearly 1000 y before finally closing
in 1988. The deposit is hosted by Middle Devonian pelitic sediments in the Rhenohercynian terrane of the Variscan Orogen.
The deposit consists of two main orebodies that have been intensely deformed. Deformation obscures the original depositional
relationships, but the regional setting as well as the geochemistry and mineralogy of the mineralisation display many characteristics
of the SHMS (sediment-hosted massive sulphide) class of ore deposits. Rammelsberg is briefly compared to the other massive
sulphide deposits in the European Variscan, including Meggen and those deposits in the Iberian Pyrite Belt.
Received: 28 September 1998 / Accepted: 5 January 1999 相似文献
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海相火山-沉积建造铁铜矿床类型及地质特征 总被引：4，自引：1，他引：4
铁-铜型矿床产出的时代从元古宙到新生代均有，与其有关的火山岩大多数为中基性与中酸性或偏碱性岩石。作者以镜的山桦树沟、陇山陈家庙和陕西铜厂不同时代的铁-铜矿床为例，概述了该类型矿床的地质特征、成矿环境并着重探了铁-铜矿床的成因机制，认为该类型矿床是与火山作用有关的喷气-沉积型矿床，同时指出柳沟峡地区及其以西（东缰地区）铁-铜型铜矿化带的发现，是进一步寻找铁-铜-金矿床的有利地段。 相似文献
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E. E. Amplieva 《Geology of Ore Deposits》2008,50(5):404-422
The sequence of orebody formation at the Talgan massive sulfide deposit; morphology of sulfide orebodies; mineralogy, texture, and structure of ore; chemical composition of minerals; and fluid inclusions and relationships between stable isotopes (S, C, O) in sulfides from ores and carbonate rocks are discussed. The deposit is localized in the Uzel’ga ore field of the northern Magnitogorsk Megazone. The sulfide ore is hosted in the upper felsic sequence of the Middle Devonian Karamalytash Formation, composed of basalt, basaltic andesite, and rhyodacite. Orebodies are irregular lenses lying conformably with host rocks. Pyrite, chalcopyrite, sphalerite, and fahlore are the major ore minerals; galena, bornite, and hematite are of subordinate abundance. Sulfide mineralization bears attributes of deposition under subseafloor conditions. The carbonate and rhyolite interlayers at the roofs of orebodies and the supraore limestone sequence served as screens. Zoning typical of massive sulfide deposits was not established. The study of fluid inclusions has shown that the temperature of the hydrothermal solution varied from 375 to 110°C. δ34S‰ ranges from ?2.4 to +3.2‰ in pyrite, from ?1.2 to +2.8‰ in chalcopyrite, and from ?3.5 to +3.0‰ in sphalerite (CDT). These parameters correspond to an isotopic composition of magmatic sulfur without a notable percentage of sulfate sulfur. δ13C and δ18O of carbonates vary from ?18.1 to +5.9‰ (PDB) and from +13.7 to +27.8‰ (SMOW), respectively. The carbon and oxygen isotopic compositions of carbonates from ores and host rocks markedly deviate from the field of marine carbonates; a deep source of carbon is suggested. The results obtained show that the main mass of polysulfide ore at the Talgan deposit was formed beneath the floor of a paleoocean. The ore-forming system was short-lived and its functioning did not give rise to the formation of zonal orebodies. Magmatic fluid played the leading role in mineral formation. 相似文献
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滇西大平掌铜多金属矿床火山喷流沉积原因 总被引：6，自引：0，他引：6
大平掌矿床由上部层状块状硫化物矿体和下部细脉浸染状矿体组成,双层结构清楚。块状矿体中发育典型的草莓状和鲕状硫化物。成矿地质背景和矿石中的金属元素及REE配分形式、S同位素组成、流体包裹体特征等均与黑矿型矿床及现代海底热液活动区硫化物矿床相似。矿床典型的火山喷流沉积成因。 相似文献
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质疑了张志斌等（2010）一文关于东升庙－三贵口锌多金属硫铁矿矿床锌矿体和硫矿体的分类及其各类矿体形态、矿石结构构造和稀土配分模式等方面的依据以及一些论证过程,否定了其在此基础上提出的锌矿体为沉积形成矿源层,后期改造成矿的观点和其得出的下一步找矿方向。锌矿体主要有9号、2号、11号等6个矿体,硫矿体主要有1号、3号、4号等4个矿体。呈层状整合分布于石墨片岩中且和后者具有一致的稀土配分模式的9号和其他矿体一样都是沉积喷流过程的产物,其矿石结构也支持这一点。在东升庙－三贵口地区下一步的找矿方向应该是寻找下部的根部矿体。 相似文献
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SONG Mingchun DENG Jun YI Pihou YANG Liqiang CUI Shuxue XU Junxiang ZHOU Mingling HUANG Tailing SONG Guozheng SONG Yingxin 《《地质学报》英文版》2014,88(3):801-824
The recent deep prospecting results in the Jiaojia area of Eastern Shandong Province indicate that the Jiaojia ore field composed of several individual gold deposits as previously suggested is actually an ultra-large gold deposit. This deposit covers an area of ~40 km2, and shows a structural control by the Jiaojia fault and its secondary faults. Gold orebodies generally occur along the same mineralization-alteration belt, and the main orebodies intersect with each other or exhibit a parallel or overlapping distribution. This deposit's reserves are estimated to be 1, 200t of gold, being the first gold deposit of more than 1000t gold reserves in China. The No. I-1 orebody in the Shaling-deep Sizhuang ore blocks holds gold reserves greater than 350 t, or 29 percent of the total reserves, followed by the No. I orebody in Matang-Jiaojia ore blocks with exceeding 150t gold reserves. This deposit mainly occurs in the footwall of the Jiaojia fault, and presents zoned patterns in mineralization, alteration and structures. The strongly mineralized zones agree with strongly altered and tectonically fractured zones. These orebodies display strataform-like, veinlike or lenticular shapes, and generally show characteristics of pinching out and reappearing, branching and converging, expanding and shrinking. The orebodies commonly occur along positions where the fault strike changes and in gentle locations with dips changing from steep to gentle. The main orebodies are parallel to the main plane of the orecontrolling fault, and tend to be gentle from the surface to the deep. The orebodies mainly plunge to the southwest, with plunge angle of 45°–60°. Orebodies near the main plane of the ore-controlling fault have more gold resource than those away from main fault zone. The slant depth of orebodies is generally larger than the length along its strike direction; orebodies become thick and gold grades become low from the shallow area to the deep area. Ore-forming fluids are H2O-CO2-NaCl±CH4 type with medium-temperature and moderate to low salinity. Sulfur isotopic values(δ34SCDT) for gold ores range between 11.08‰ and 12.58‰, indicating mixed sulfur sources; hydrogen isotopic values(δDVSMOW) range from-83.68‰ to-116.95‰ and oxygen isotopic values(δ18OV-SMOW) range between 12.04‰ and 16.28‰. The hydrogen and oxygen isotopes suggest that ore-forming fluids originated from primary magma, and mixing with a large amount of atmospheric water during the late stage. The Eastern Shandong Province gold deposits are associated with magmatic activities which have mantlecrust-mixed source, and also share some similarities with orgenic and epithermal hydrothermal gold deposits. Because Eastern Shandong Province gold deposits with unique metallogenic features and formation setting which are different from other gold deposit types in the world, we call it the Jiaojiatype gold deposits. The kiloton class Jiaojia gold deposit is related to fluid activities, extension and detachment resulted from thermal upwelling of magmas. The strong magmatic activities in the middle to late stage of early Cretaceous in Eastern Shandong Province lead to active fluids, and provided abundant ore-forming materials for gold depsoits. Moreover, many extensional structures resulting from crustal extension provided favourable space for orebody positioning. 相似文献
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通过对新桥硫-多金属矿床含硫磁铁矿矿体赋存空间、构造环境、岩矿组合、围岩蚀变等宏观地质特征的研究,并结合微量元素,硫、铅、氢、氧同位素、矿物包体测温等资料综合分析认为:本区成矿物质来源为中深相幔源岩浆或同熔岩浆,进而研究矿床含硫磁铁矿体应属高温热液交代-后期热液叠加改造成因类型。 相似文献
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河北张家口金矿南冷沟矿段构造控矿特征分析 总被引：2，自引：0，他引：2
南冷放段金矿体赋存于张家口金矿主脉带中,但成因与张家口金矿矿体明显不同,金矿全的形成和分布这ＳＮ向断裂及其ＮＷ向羽状分支构造控制。根据矿石自然类型要带,可划人灵原生含金硫化物石英脉型、原生含硫化物钾长石石英脉型和氧化矿体３个带,分别为近ＳＮ向断裂及其ＮＷ向状分支构造所围限,在Ｆ４断层东盘依次出现,氧化程度逐渐增高。 相似文献
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The Ashele Cu-Zn deposit is a typical VMS deposit in Chinese Altay located in the southern margin of the Altaid orogen. The deposit occurred in the polyphase fold system, and the main orebody is located at the hinge of the syncline. All orebodies show lenticular form, and are stratabound by a suite of early to middle Devonian bimodal volcanic rocks. The hosting basalt is low K tholeiite and characterized with high Mg, Fe, Ca and low K, Ti. These basalts show flat REE pattern with Ce negative anomaly (Ce/Ce* 0.73–0.76). Niobium, Ta, Zr, Hf are depleted and Rb, Ba, Th, U, Sr, Pb are enriched with respect to the N-MORB. Both the Sr and Nd isotopes show depleted properties, while the (87Sr/86Sr)i and the εNd(t) range from 0.70469 to 0.70488 and 4.6 to 5.3, respectively. All geochemical and isotopic data from the hosting basalt show that it originates from an island arc source. We also report the S isotope data from the massive orebody, and δ34S‰ change from 1.8‰ to 5.6‰. The S isotope data provide evidence that the sulfur originates from a mixing source between magma and seawater sulfate. We propose that the mafic magma provides the ore-forming metal and some percentage of sulfur, while it also acts as a heat engine which makes the fluids leach the metal from the underlying volcanic rocks. Combining the geological characteristics of the Ashele and geochemical data, and comparing with other Cu-Zn VMS deposits in the world, we propose that Ashele formed in a rifted arc setting. 相似文献