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1.
内蒙古毛登锡铜矿床地质及成因   总被引:2,自引:3,他引:2  
刘玉强 《矿床地质》1996,15(2):133-143
内蒙古毛登锡铜矿床是大兴安岭南段的锡多金属矿床之一。该矿床是与阿鲁包格山花岗斑岩(Rb-Sr等时线年龄149×10^-6a),锶同位素初始比值为0.705)有关的具中等成矿深度和成矿温度的热液脉型锡铜矿床。矿床中主要产出锡矿体,它们分别以微脉、细脉和大脉的形式充填于自接触带向外的NW向断裂裂隙系统中。钾化(磁铁矿矿化)、云英岩化(锡石或辉钼矿矿化)和硅化(硫化物矿物)三个蚀变-矿化阶段流体的温度和  相似文献   

2.
内蒙古大井锡铜多金属矿床流体成矿机理及外围找矿预测   总被引:3,自引:1,他引:2  
大井矿床老区锡铜及老区东部砷铜石英脉矿体是大井矿床的一个矿化中心,从该矿化中心向外,流体均一温度、盐度递减,由老区的Sn、Cu及老区东部As、Cu矿体向外逐渐演化为晚阶段Sn及Cu、Pb、Zn、Ag矿体。老区中心富锡及富铜流体是不同来源的流体,反映了该矿床可能存在不同的多个矿化中心,来自不同矿化中心不同矿化阶段的流体在同一空间叠加成矿。大井矿床西区的西北部预测区细脉浸染状矿体成矿流体与大井矿区脉状矿体的流体完全不同,总体显现了斑岩型流体包裹体的高温-高盐度及流体沸腾的特征。推测大井矿床外围预测区可能是大井矿床另一个矿化中心,其深部可能存在斑岩型矿化的新类型。  相似文献   

3.
黄沙坪铅锌矿床中银矿化组合特征   总被引:6,自引:0,他引:6  
研究黄沙坪铅锌矿床中银矿化组合表明:与301花岗斑岩和304花斑岩岩体有关铅(锌)-银-锡-锑矿化组合,银矿化伴随铅矿化出现,其微量元素富Sn、Sb、Ag,低Bi、Te、Mo、Wo、W为特征;银矿物组合以硫银锡矿-银黄锡矿-深红银矿-螺状硫银矿-硫锑铜银矿组合为特征,与石英斑岩有关的铜(钼)-银-碲矿化组合,铜矿石以高Te、Bi、Mo和W,低Sb为特征,银矿物组合以碲银矿-六方碲银矿-粒碲银组合和硫银铋矿-块辉铋铅银矿-碲银矿组合为特征  相似文献   

4.
本文对云南境内燕山期花岗岩和不同类型锡矿微量元素的地球化学特征作了综合判析。指出从印支期到喜山期,随着花岗岩的时代由老到新,含锡量逐渐增高。燕山晚期花岗岩一般含锡在20ppm左右,並且富含Nb、W、Pb等元索和挥发分F。这是在燕山晚期出现大量锡(钨)矿化並形成矿床的一个重要前提。不同类型的锡矿具有不同的元素组合特征。锡石——硫化物型为Sn、(W)、Cu、Pb、Zn、As组合,有时出现Ag、cd、In;云英岩型和石英电气石型分别以Sn、W、(Cu)及Sn、B、Cu、Pb、As为主;锡石——伟晶岩型为Nb、Sn、Be、Li、Cs。各种锡矿类型的锡石微量元素含量也有明显差异,一般硫化物型含Cu、(Pb)、As最高;伟晶岩型富含Nb、Ta、Sc;锡石——石英型含Ti普遍较高。  相似文献   

5.
复兴屯矿床位于大兴安岭南段,是一个以银为主,伴生铅锌的超大型矿床。矿体产于早白垩世火山岩及火山碎屑岩中,发育贫铁闪锌矿+方铅矿+黄铜矿+(银)黝铜矿的矿物组合,围岩蚀变以碳酸盐化、高岭土化和叶腊石化为主。其成矿可以划分为以下3个阶段:铜锌硫化物阶段(阶段Ⅰ)、铅锌硫化物阶段(阶段Ⅱ)和银锌硫化物阶段(阶段Ⅲ)。文章对复兴屯矿床闪锌矿开展了LA-ICP-MS微量元素分析,矿床中闪锌矿以富集Cu、Ag、Pb,贫Fe、Cd、Ga、Ge为特征。矿床闪锌矿均为贫铁闪锌矿,暗示复兴屯矿床形成于中低温环境。由阶段Ⅰ至阶段Ⅲ,闪锌矿中的Fe、Mn、In含量逐渐降低,Ga、Ge、Sb含量略有增加,暗示成矿流体温度逐渐下降。复兴屯闪锌矿中Ag可与Cu联合置换Zn进入闪锌矿晶格,这可能是复兴屯矿床闪锌矿中Ag含量高的重要因素。此外,闪锌矿中常见韵律环带,反映了闪锌矿形成过程中成矿流体有多次压力波动,成矿流体多次压力波动引发的流体相分离是矿质沉淀的主要机制之一。闪锌矿微量元素含量与中低温岩浆热液矿床基本一致,明显区别于MVT型矿床、块状硫化物矿床、矽卡岩型矿床和中高温岩浆热液矿床,结合矿床地质特征,认为复兴屯银铅锌矿床属于浅成低温热液矿床。  相似文献   

6.
侯增谦 《地球化学》1996,25(3):228-241
选择西南太平洋冲绳海槽现代海底烟囱硫化物矿床、日本小坂矿山上向黑矿(第三纪)和中国西南呷村黑矿型矿床(三叠纪)进行了矿石地球化学比较研究。黑矿型矿床矿石吨位-品位模式与其他火山成因块状硫化物(VMS)矿床类似,矿田(20-50km^2)矿石吨位与单个喷气-沉积型(Sedex)矿床相当,金属总量4-6Mt,为矿田范围内热液流体搬运的最大金属量。与洋脊环境VMS矿床相比,岛弧裂谷环境产出的黑矿型矿床相  相似文献   

7.
矽卡岩型金属矿床是内蒙古东南部重要的矿床类型,集中分布在黄岗梁-乌兰浩特铜多金属成矿带西南段,其代表性矿床有白音诺铅锌矿床和浩布高铅锌铜锡矿床以及黄岗铁锡矿床,是中国北方重要的铅锌矿和锡矿产地。总结、分析了此类型矿床中的代表性金属矿床的物化探勘查方法及其有效性,建立了矽卡岩型金属矿床地、物、化综合找矿模式。此类金属矿床多分布于黄岗-乌兰浩特铜多金属成矿带西南段二叠系大理岩或结晶灰岩夹层内,其受构造作用形成的复背斜轴部的虚脱部位是赋矿的有利场所。金属矿化特别是铅锌矿化与锰钙质辉石矽卡岩关系密切。矿床所在地区主要地层和酸性侵入岩类主要金属元素Cu、Pb、Zn、Ag、Sn的质量分数均大大高于背景值,并在矿带、矿化蚀变带和出露矿体上呈现高强度、衬度高、分带清晰的局部异常。成晕元素具有较好的分带性:矿体前缘晕为As、Sb、Hg、Pb、F;尾晕为Sn、W、Mo。矿体和矿化矽卡岩上常呈现高极化率、高磁力、高重力、低电阻率(三高一低)的组合异常特征。  相似文献   

8.
广西大厂锡矿铟的地球化学特征及成因机制初探   总被引:10,自引:3,他引:10  
广西大厂锡矿位于江南古陆西南缘,桂西北海西-印支期被动陆缘裂谷盆地北部的断裂凹陷盆地中,是中国重要的、以锡为主的有色金属矿床。它主要由长坡-铜坑和高峰矿床、拉么矿床、大福楼矿床和亢马矿床等组成,其铟资源量约6 000 t。文章在对长坡-铜坑矿床、高峰矿床以及拉么矿床不同类型围岩(包括花岗岩质岩石)、矿石以及不同矿床类型中矿石矿物(硫化物和氧化物)中的In、Cu、Cd、Sn、Fe、Zn等微量元素分析的基础上,结合不同类型矿床、不同矿物组合中硫化物的微量元素电子探针测试以及硫同位素分析结果,初步认为大厂锡矿岩浆源区是富铟的,在正常的沉积岩中不存在铟的初始富集;In主要赋存于闪锌矿中,与层状和块状的矿体关系密切。在成矿作用过程中,In的分布和富集对矿物组合和矿石类型具有明显的选择性。大厂铟矿的形成是富铟的岩浆源区重融产生含铟岩浆,在岩浆侵位冷却过程中,由岩浆结晶所产生的流体携带In、Cu、Fe、Zn、Sn等成矿元素从岩浆中出溶,形成含In的成矿流体。水-岩反应以及在大气降水来源流体的参与下,导致In、Cu、Fe、Zn、Sn等从成矿流体中沉淀、富集成矿。  相似文献   

9.
东秦岭二郎坪群蛇绿岩中的火山成因块状硫化物矿床   总被引:2,自引:0,他引:2  
二郎坪群蛇绿岩中多金属矿床属火山成因块状硫化物矿床。加里东期火山作用早期形成铁(铜)矿层、中晚期随着酸性火山岩的增多和火山爆发作用的加强,形成火山成因块状硫化物矿床和黄铁矿化层。矿床具有距火山喷发中心远近不同的分带性和厚层基性熔岩成铁(铜)矿、酸性火山岩赋存铜-锌型或铅-铜型矿的成矿专属性。后者伴有金银矿化。  相似文献   

10.
云南蒙自白牛厂银多金属矿区深部找矿的新发现   总被引:1,自引:0,他引:1  
云南白牛厂银多金属矿床是我国20世纪80年代后发现的超大型矿床之一。近年来作者通过对其控矿因素的进一步研究,突破了断裂控矿、层位控矿的认识局限,提出了成矿作用主要与燕山晚期花岗质岩浆活动有关;随着与隐伏花岗岩体接触带距离的加大,出现Sn(Fe)→Cu→Zn→Pb→Ag→Sb的矿化空间分带规律新认识。在分析深部岩体产状及地球物理勘查(高频大地电磁测深扫面)基础上,认为锡、铜是矿区南部深部的主要勘查目标,经钻探验证,发现了厚大的铜矿体和富锡矿体.  相似文献   

11.
We present the first platinum group elements (PGE) data on seven massive sulfide deposits in the Iberian Pyrite Belt (IPB), one of the world largest massive sulfide provinces. Some of these deposits can contain significant PGE values. The highest PGE values were identified in the Cu-rich stockwork ores of the Aguas Teñidas Este (Σ PGE 350 ppb) and the Neves Corvo (Σ PGE 203 ppb) deposits. Chondrite normalized PGE patterns and Pd/Pt and Pd/Ir ratios in the IPB massive, and stockwork ores are consistent with the leaching of the PGE from the underlying rock sequence.  相似文献   

12.
In the Iberian Pyrite Belt, volcanic rocks are relatively scarce, accounting for approximately only 25% of the geologic record, with the remaining 75% consisting of sedimentary units. This association is very clear in the host succession to the Neves Corvo massive sulfide deposit in Portugal. The Neves Corvo host succession comprises the products of explosive and effusive rhyolitic eruptions intercalated with mudstone that records a submarine below-wave-base environment and provides precise biostratigraphic age constraints. The first and second volcanic events involved eruptions at local intrabasinal vents. The first event generated thick beds of fiamme breccia that are late Famennian in age. The fiamme were originally pumice clasts produced by explosive eruptions and were subsequently compacted. The second event was the late Strunian (latest Famennian) effusion of rhyolitic lava that was pervasively quench-fragmented. The third and final event is younger than the massive sulfide deposits poorly represented in the mine area and minor compared with the two other events. The integration of biostratigraphic data with the volcanic facies architecture indicates that the Neves Corvo ore deposits are similar in age to the late Strunian rhyolitic lava. Although regionally the Iberian Pyrite Belt is essentially a sedimentary succession, ore formation at Neves Corvo can be closely linked to discrete volcanic events that produced a relatively narrow range of volcanic facies.  相似文献   

13.
The Chitradurga base metal sulfide deposit is associated with eugeosynclinal metabasalts (~ 2.5 b.y.) and banded pyritiferous cherts. The pre-tectonic character of the deposit and meta-volcanics is indicated by their deformational textures, structures and radioactive age data. The mineral assemblages of these ores are similar to the Zn-Cu type of massive sulfide deposits associated with Archean—Early Precambrian eugeosynclinal metavolcanics in other shield areas. The deposit has a rather high concentration of Co; microprobe data indicate that most of it is found as cobaltite and linnaeite and that it is inhomogenously distributed in these minerals. Very strong sympathetic correlation between Co and Cu, and the simultaneous increase of both of these elements with depth has been found. The geochemistry of the Chitradurga ores and metabasalts, especially their Zn:Cu:Pb and Pb:Zn ratios, suggests that the base metal sulfide content is probably genetically related to the basaltic flows. It appears that the Chitradurga deposit belongs to the ‘massive volcanogenic’ Cu-rich class of sulfide deposits. The metal content of the ores appears to have been supplied by rapidly degassing highly undifferentiated protomantle along with the basaltic magma.  相似文献   

14.
The Dongshengmiao Pb-Zn deposit located in the Mesoproterozoic aulacogen in a passive continental margin in the north- west margin of the North-China Craton is widely considered to be a untypical SEDEX deposit.Recently,new types of mineralization such as chalcopyrite veins and re-crystallized sphalerite ores with visible hydrothermal alteration have been found in the deposit at depth.In this paper we report the decrepitation temperatures of fluid inclusions in chalcopyrite,sphalerite and quartz from these new types of ores.The decrepitation temperatures of fluid inclusions in chalcopyrite(4 samples),sphalerite(2 samples)and quartz(5 samples)are 303~456℃,97~497℃,146~350℃and 350~556℃,respectively.The decrepitation temperatures of fluid inclusions in the vein-type chalcopyrite are similar to the decrepitation temperatures of fluid inclusions in chalcopyrite from the Hercynian Oubulage porphyry Cu-Au deposit(313~514℃)and the Chehugou porphyry Cu-Mo deposit(277~485℃),supporting our interpretation that the Dongshengmiao deposit was overprinted by magmatic hydrothermal mineralization.The decrepitation temperatures of fluid inclusions in re-crystallized sphalerite from the Dongshengmiao deposit are characterized by two peaks,97~358℃and 358~497℃.The decrepitation temperatures of fluid inclusions in quartz in ehalcopyrite veins from the Dongshengmiao deposit are also characterized by two peaks,146~350℃and 350~556℃.The lower and higher temperature peaks in both cases are considered to represent two separate mineralization events,original SEDEX mineralization and magmatic hydrothermal overprinting,respectively.The higher decrepitation temperatures of fluid inclusions in quartz and sphalerite from the Dongshengmiao deposit are similar to the decrepitation temperatures(340~526℃)of fluid inclusions in sphalerite from the Baiyinnuoer skarn-type Pb-Zn deposit in the region. Replacement of pyrite by sphalerite and overgrowth of chalcopyrite on pyrite in the Dongshengmiao support our interpretation that the original SEDEX mineralization was overprinted by magmatic hydrothermal activity in the deposit.Our results suggest that there may be separate porphyry and skarn-type deposits related to Hercynian magmatism and associated hydrothermal activities in the Langshan area, which are potential exploration targets in the future.  相似文献   

15.
Abstract: The Ashele Cu-Zn deposit is a recently discovered volcanogenic massive sulfide deposit in Xinjiang, Northwestern China. It is the largest Cu-Zn deposit in this type of deposits in China, which were formed in the early period of later Palaeozoic Era. This deposit is hosted within a suit of bimodal submarine volcanic rocks of the Ashele Formation of Lower-Middle Devonian System formed in an environment of paleocontinental margin rift setting. Lensoid orebodies occur between spilitic rocks developed at footwall and quartz-keratophyric tuff at hanging wall. Zonation of metal elements in the Ashele mine is one of typical volcanic-related exhalative Cu-Zn sulfide deposits in the world. Black ores enriched in Pb, Zn and Ag occurs on the top of the No. 1 orebody in the Ashele deposit, yellow ores enriched in Cu in the middle part, and the chalcopyritization stringer below the massive sulfide ores. Zonation of ore-structure in the No. 1 orebody is also apparent and corresponds to the zoning of elements, i. e. lamellar and/or banded sulfide-sulfate ores on the top, massive sulfide ores in the middle, and stockwork veinlets associated with altered breccia pipe on the bottom. Four epochs of mineralization in the Ashele deposit has been recognized. The first period of syngenetic-exhalative deposition of sulfides is the main epoch of mineralization, and the ores deposited subsequently subjected to thermo-metamorphism at the second epoch, superimposed by hydrothermal mineralization at the third epoch, and weathered or oxidized at the fourth epoch.
More than 100 categories of minerals have been recognized in the Ashele mine, but only pyrite, chalcopyrite, sphalerite, tetrahedrite, galena, barite, quartz, chlorite, sericite, and calcite are dominant, making up various types of ores, and alteration pipes or horizons. Studies of ore petrology suggest that the massive ores were volcanogenic and deposited by exhalative process.  相似文献   

16.
平水铜矿是位于扬子板块和华夏板块结合带(即钦杭结合带)北东段的典型火山岩型块状硫化物矿床,其铜矿主要形成于石英-黄铁矿-黄铜矿-闪锌矿阶段。本文对其块状矿体下部发育的含硫化物石英脉中锆石进行了LA-ICP-MSU-Pb精确测年,CL图像和Th/U比值显示锆石多为岩浆成因,测年数据可分为5组:981~988Ma、(950±15)Ma、(926±13)Ma、(899±21)Ma和93~120Ma。地质证据和定年结果表明平水铜矿的成矿年龄为新元古代早期(~899Ma),白垩纪的热事件(93~120Ma)对矿体进行了叠加改造作用。这一认识对深入了解平水铜矿的成因、形成和演化具有重要地质意义,同时提供了在钦杭结合带寻找火山岩型块状硫化物矿床的年代学信息。  相似文献   

17.
新疆哈密卡拉塔格块状硫化物矿床金银赋存状态研究   总被引:3,自引:0,他引:3  
新疆哈密红海黄土坡VMS矿床位于东天山卡拉塔格隆起带,是卡拉塔格矿集区内新发现的块状硫化物矿床。矿体产于卡拉塔格隆起带核部火山沉积岩建造中,具有典型的VMS型矿床“上层下脉”二元结构特征。该矿床中含金硫化物矿石主要有块状黄铁矿黄铜矿、块状黄铁矿黄铜矿闪锌矿、块状黄铁矿闪锌矿黄铜矿和块状闪锌矿。文中在对各类含金硫化物矿石进行详细的矿相学研究基础上,结合扫描电子显微镜与能谱仪联用技术(SEM/EDS),对硫化物样品中金、银的赋存状态进行研究。结果表明,4种块状硫化物中的主要矿物形成于多个期次,主要包括VMS成矿期(黄铁矿阶段、闪锌矿黄铜矿黝铜矿方铅矿阶段、石英重晶石阶段)、热液叠加期(石英黄铁矿黄铜矿闪锌矿方铅矿阶段)和表生期(铜蓝纤铁矿阶段)。矿区首次发现4颗金银金属互化物(银金矿、碲银矿),其较大的化学成分差异指示了热液环境由中酸性中性转变为更有利于Au、Ag迁移沉淀的偏碱性。后期的偏碱性热液对VMS成矿期形成矿物产生了交代作用,使得Au、Ag活化再富集。由于后期热液叠加改造,红海VMS型矿床中Au、Ag不仅赋存于VMS成矿期后期中低温闪锌矿黄铜矿阶段,也赋存于VMS成矿期早期中高温黄铁矿阶段,并贯穿整个热液叠加期。各含金矿物组合中除4颗金银金属互化物外Au多呈显微不可见状态,推测Au、Ag主要以原子或离子形式赋存于矿物晶格中或矿物空位处。  相似文献   

18.
The study of base-metal massive sulfide and tin–sulfide deposits in Siberia and the Russian Far East has revealed that the indium content in ores exceeding the average statistical value at similar deposits worldwide could be economically important. Sphalerite and chalcopyrite and chalcopyrite, bornite, and sphalerite are the major indium carriers in the base-metal massive sulfide and tin–sulfide ores, respectively. In addition, base-metal massive sulfide ores have high Cd, Ag, and Te contents, whereas tin–sulfide ores have elevated Ge, Ga, and Nb contents. This has stimulated the investment attractiveness of these deposits.  相似文献   

19.
The Karchiga copper massive sulfide deposit is located in the Kurchum block of high-grade metamorphosed rocks. This block is part of the Irtysh shear zone, which belongs to the largest transregional fault in Central Asia. The deposit is associated with the gneiss–amphibolite middle unit of the metamorphic complex, which is distinct in the geochemical fields. The mineralization is spatially and paragenetically related to the amphibolite beds, which are ore-bearing together with terrigenous rocks.The deposit contains two spatially isolated lodes, in which all the discovered commercial reserves concentrate. They conformably overlie the host rocks and are tabular or ribbonlike. The mineralization has a close spatial relationship with Mg-rich anthophyllite-containing rocks. The sulfide ores are disseminated or massive and comprise pyrite, chalcopyrite, pyrrhotite, sphalerite, and magnetite. The ore is of Zn–Cu composition, in which Cu dominates considerably over Zn (average contents 2 and 0.4%, respectively; Cu/(Cu + Zn) = 0.83). The ores are rich in Co (up to 0.16%, averaging 0.02%), poor in Au and Ag (0.3 and 7.2 ppm, respectively), and almost free of Pb and Ba.All the rocks and ores experienced epidote–amphibolitic metamorphism. Meanwhile, the ores experienced a recrystallization and partial regeneration, but the initial shape of the lodes remained unchanged.The essentially chalcopyritic ores, the volcaniclastic ore-bearing rocks, and the spatial and genetic relationship of the mineralization with undifferentiated mafic and siliciclastic rocks suggest that this deposit belongs to the Besshi type, formed in a back-arc environment, near large rises.The studies show that Besshi-type Cu–Zn massive sulfide deposits differ from most of the polymetallic (Kuroko-type) deposits in Rudny Altai in the composition of volcanics and geodynamic settings, but belong to the same evolutionary series in this VMS province. Both types of deposits might have formed in the Paleozoic, during the main peak of VMS generation in the Earth's history.  相似文献   

20.
The Eagle Ni–Cu–(PGE) deposit is hosted in mafic–ultramafic intrusive rocks associated with the Marquette–Baraga dike swarm in northern Michigan. Sulfide mineralization formed in association with picritic magmatism in a dynamic magma conduit during the early stages in the development of the ~1.1?Ga Midcontinent Rift System. Four main types of sulfide mineralization have been recognized within the Eagle deposit: (1) disseminated sulfides in olivine-rich rocks; (2) rocks with semi-massive sulfides located both above and below the massive sulfide zone; (3) massive sulfides; and (4) sulfide veins in sedimentary country rocks. The disseminated, massive and lower semi-massive sulfide zones are typically composed of pyrrhotite, pentlandite and chalcopyrite, whereas the upper semi-massive sulfide ore zone also contains pyrrhotite, pentlandite, and chalcopyrite, but has higher cubanite content. Three distinct types of sulfide mineralization are present in the massive sulfide zone: IPGE-rich, PPGE-rich, and PGE-unfractioned. The lower and upper semi-massive sulfide zones have different PGE compositions. Samples from the lower semi-massive sulfide zone are characterized by unfractionated PGE patterns, whereas those from the upper semi-massive sulfide zone show moderate depletion in IPGE and moderate enrichment in PPGE. The mantle-normalized PGE patterns of unfractionated massive and lower semi-massive sulfides are subparallel to those of the disseminated sulfides. The results of numerical modeling using PGE concentrations recalculated to 100% sulfide (i.e., PGE tenors) and partition coefficients of PGE between sulfide liquid and magma indicate that the disseminated and unfractionated massive sulfide mineralization formed by the accumulation of primary sulfide liquids with similar R factors between 200 and 300. In contrast, the modeled R factor for the lower semi-massive sulfide zone is <100. The fractionated sulfide zones such as those of the IPGE-rich and PPGE-rich massive sulfides and the upper semi-massive sulfide zone can be explained by fractional crystallization of monosulfide solid solution from sulfide liquids. The results of numerical modeling indicate that the sulfide minerals in the upper semi-massive sulfide zone are the products of crystallization of fractionated sulfide liquids derived from a primary sulfide liquid with an R factor similar to that for the disseminated sulfide mineralization. Interestingly, the modeled parental sulfide liquid for the IPGE-rich and PPGE-rich massive sulfide zones has a higher R factor (~400) than that for the unfractionated massive sulfide mineralization. Except one sample which has unusually high IPGE and PPGE contents, all other samples from the Cu-rich sulfide veins in the footwall of the intrusion are highly depleted in IPGE and enriched in PPGE. These signatures are generally consistent with highly fractionated sulfide liquids expelled from crystallizing sulfide liquid. Collectively, our data suggest that at least four primary sulfide liquids with different R factors (<100, 200–300, ~400) were involved in the formation of the Eagle magmatic sulfide deposit. We envision that the immiscible sulfide liquids were transported from depth by multiple pulses of magma passing through the Eagle conduit system. The sulfide liquids were deposited in the widened part of the conduit system due to the decreasing velocity of magma flow. The presence of abundant olivine in some of the sulfide ore zones indicates that the ascending magma also carried olivine crystals. Sulfide saturation was attained in the parental magma due in large part to the assimilation of country rock sulfur at depth.  相似文献   

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