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福建碧田铜金银矿床中硫盐矿物及钨锡硫化物研究 总被引：6，自引：0，他引：6
福建碧田矿床成因上是与燕山晚期次火山岩有关的、以银为主的大型铜金银矿床。该矿床产于燕山早期花岗岩中,在其铜矿石内发现了较多的锌砷黝铜矿、铋砷黝铜矿、铋锑黝铜矿、碲砷黝铜矿、针硫铋铅矿、硫铋铜矿、硫砷铜矿等硫盐矿物及少见的钨锡硫化物——硫锡铁铜矿、硫铁锡铜矿和硫钨锡铜矿。这些矿物形成于成矿作用早期的黄铜矿-斑铜矿-黄铁矿阶段。成矿温度在260～380℃之间,最低成矿压力20～40 MPa,硫逸度(lgfs_2)=-8.74～-12.06。钨锡铋矿物的发现表明,燕山早期花岗岩可能为成矿提供了部分物质来源。 相似文献
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鸡笼山矽卡岩型金铜矿床是长江中下游成矿带典型的矽卡岩矿床,矿体主要赋存于下三叠统大冶组碳酸盐岩与花岗闪长斑岩接触带内。根据野外观察和镜下鉴定,将成矿过程划分为进矽卡岩阶段、退化蚀变阶段、石英-硫化物阶段和碳酸盐阶段,其中石英-硫化物阶段为金和铜的主要成矿阶段。鸡笼山金铜矿床中不同类型矿石的矿相学观察和电子探针微区成分分析(EPMA)表明,金、银主要以自然金、银金矿、碲银矿、硫银铋矿等形式产出,主要载金矿物为黄铜矿和黄铁矿;同时发现鸡笼山金铜矿床中发育大量碲-铋矿物(如辉碲铋矿、针硫铋铅矿等)。成矿流体物理化学性质研究表明,鸡笼山金铜矿床中金银元素在高温热液中主要以氯络合物的形式运移,随着温度降低和流体进一步的演化,金银元素转变为以硫络合物、碲铋化物熔体等形式运移。在石英-硫化物阶段,由于硫化作用与流体的沸腾作用,流体中硫逸度降低,碲逸度升高;当流体处于黄铁矿-磁黄铁矿氧逸度范围、酸碱性呈中性-弱碱性、碲逸度(logf_(Te2))为-10.7~-8.4、硫逸度(logf_(S_2))为-11.4~-10.6时,金、银、铜元素近于同时沉淀,碲、铋和砷元素对金和银元素运移和富集起到了重要作用,最终形成了鸡笼山矽卡岩型金铜矿床。 相似文献
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碲是一种重要的战略性关键金属,主要以共伴生形式产出多个类型矿床中,斑岩-矽卡岩型矿床是碲资源重要的来源之一。城门山铜金矿床是长江中下游成矿带中一典型斑岩-矽卡岩型矿床,也是该区目前已报道的最大的共伴生碲矿床,然而碲在该矿床的赋存状态、碲的沉淀机制等尚不清楚。本文在详细划分成矿阶段基础上,对该矿床不同类型矿石中的矿物开展电子探针测试、LA-ICP-MS微量元素分析以及面扫描研究工作。测试结果表明碲元素主要以碲银矿、碲铋银矿等碲化物和辉碲铋矿、硫楚碲铋矿、碲黝铜矿等碲的硫化物形式存在,少量呈类质同象赋存在黄铁矿和黄铜矿中。黄铜矿中Te含量在矽卡岩型矿石中变化范围(0.15×10~(-6)～20.50×10~(-6))大于碳酸盐岩交代型矿石(0～3.44×10~(-6))。黄铁矿中Te含量在碳酸盐岩交代型矿石中最高,可达173×10~(-6);黄铁矿mapping显示在同一颗矿物中Te含量分布也不均匀。通过300℃logf_(Te_2)-logf_(S_2)相图分析,硫逸度介于-6.8～-11.4,碲逸度介于-7.8～-14.8;自花岗闪长斑岩向碳酸盐岩地层围岩,从成矿早阶段到晚阶段,硫逸度和温度逐渐降低,碲逸度升高,这是城门山矿床碲矿物沉淀的主要机制。城门山矿床中无论是单颗粒黄铁矿硫同位素还是原位硫同位素均显示岩浆来源特征,结合岩相学碲矿物与黄铁矿等硫化物密切共生,具有成因联系,表明碲的成矿物质来源也应为岩浆来源,与花岗闪长斑岩岩浆热液作用有关。 相似文献
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吉林小西南岔金铜矿床的金属矿物及矿石特征。 总被引：3，自引：0，他引：3
小西南岔矿床是与燕山期花岗岩有关的斑岩矿床，以金、铜为主，伴有银、铋矿化。金属硫化物主要是黄铁矿、毒砂、磁黄铁矿、黄铜矿。金矿物是金－银系列的自然金、银金矿及金银矿。金的成色低，平均成色７２８，且变化在３０５～９９３这一较大范围内。另外，还发现了碲银矿、硫碲银铋铅矿、自然铋、赫啼铋矿、富硫铋铅矿等多种银、铋矿物。成矿早期只有微弱的铜（钼）矿化，大量金和铜富集于成矿中期（２１０～４７５℃），而银、铋矿化则出现在成矿作用晚期（１６０～２４０℃）。 相似文献
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东珺矿床是近年在内蒙古额尔古纳地区陆相火山岩系内新发现的一处脉状Pb-Zn-Ag矿床,其以富含多量Ag及微量Au为特征。在野外考察的基础上,本文以电子探针、能谱-扫描电镜及多项光谱分析等方法查明了其矿石中Au、Ag的赋存状态及矿物组成,其主要矿物包括辉银矿、火硫锑银矿、黝锑银矿、深红银矿、硫锑铜银矿及脆银矿。除此,还发现了一些罕见的矿物,如碲铋矿、硫锑铜矿的锌变种、针硫铋铅矿、库辉铋铜铅矿以及某些未知的Pb-Bi相金属矿物。为了估算本矿床的成矿温度,着重对矿床中的银锑黝铜矿系列的组成做了分析,并将其Ag/(Ag+Cu)及Zn/(Zn+Fe)数值投至Sack等温曲线图上,由其结果可判断出本矿床应属于浅成低温成因,而深部矿体中碲铋矿及无Ag硫盐的出现亦可视为一重要旁证。东珺矿床丰富的银矿物及其粗大粒度对于矿山工艺流程选定以及开发利用将会大有裨益,而本矿床Au含量过低,仅具有地球化学的理论意义。 相似文献
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江西盘古山钨矿是一个钨、铋、碲均可综合利用的大型矿床,有关其碲化物的特征及成矿流体的物理化学条件研究尚属空白.文章在整理和总结前人研究成果的基础上,对矿床中碲化物开展了详细的矿相学鉴定、电子探针和流体包裹体测温.结果显示,盘古山钨矿床的碲化物主要有硫碲铋矿A、硫碲铋矿B、应硫碲铋矿、巴硫碲铋矿、硫楚碲铋矿及辉碲铋矿.矿床碲化物由浅至深有依次出现硫碲铋矿A、巴硫碲铋矿、硫碲铋矿B、应硫碲铋矿、硫楚碲铋矿、辉碲铋矿的趋势,矿物逐渐富Te元素而贫Bi、S元素.流体包裹体测温显示碲化物最小捕获温度为152～395℃,碲逸度为-11.0＜1ogf(Te2)＜-7.1,硫逸度为-12.54＜logf(S2)＜-9.39.研究认为,温度和f(S2)的降低,及f(Te2)/f(S2)的相对增大是碲化物沉淀的关键因素.碲化物的空间分带可能是随着成矿流体物化条件的变化导致Bi2S3-PbS矿物系列中Bi被Pb置换、S被Te置换的结果. 相似文献
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双尖子山Pb- Zn- Ag矿床位于黄岗- 甘珠尔庙多金属成矿带的东北段,是目前发现的中国最大的银矿床。本文通过野外地质调查、矿相学鉴定、电子探针背散射图像以及电子探针化学成分分析,对该矿床金属矿物的矿物学特征进行了详细研究,同时对金属矿物的化学式进行了计算,并对银的富集机理进行了探讨。银矿物主要以可见银(>50μm)的形式产出,包括独立银矿物：硫锑铜银矿、硫银锡矿、辉硒银矿、深红银矿、脆银矿、黝锑银矿、螺状硫银矿、金银矿和自然银等;不可见银含量少,主要以类质同象形式赋存在方铅矿中。矿床成矿阶段细分为：①石英- 高Fe闪锌矿- 富Se和Bi的方铅矿- 富Se富Sb富Sn的银矿物阶段;②石英- 方铅矿- 富Fe闪锌矿- 毒砂- 富Sb富Sn少Se的银矿物阶段;③石英- 闪锌矿- 方铅矿- 银矿物阶段;④黄铁- 碳酸盐阶段。金属矿物沉淀顺序为：(黄铁矿、黄铜矿、闪锌矿、方铅矿)→银的硫盐矿物→银的硫化物→自然银。矿床中的Fe+、Cu+、Zn+、Pb+、Ag+等金属离子在早期中温高硫逸度阶段主要以硫氢络合物形式搬运。随着成矿热液温度的降低,铅、锌等金属硫氢络合物开始分解,方铅矿、黄铜矿和闪锌矿等硫化物得以沉淀,此时部分银以显微和次显微包体银的形式被包裹于这些硫化物中,铅锌硫化物的大量沉淀引起成矿热液组成和性质的显著变化,最终导致银从硫氢络合物中彻底解体,并与Cu+、Sb3+等离子结合形成大量独立银矿物(如深红银矿、硫锑铜银矿等)。随着温度、盐度持续降低,硫逸度也逐渐降低,pH值升高,成矿流体中出现大量自由Ag+并逐渐达到饱和,银矿物开始大量沉淀,Ag+与H2S发生作用形成螺状硫银矿。自然银的大量出现标志着银的沉淀过程趋于结束。金属矿物沉淀顺序为：(黄铁矿、黄铜矿、闪锌矿、方铅矿)→银的硫盐矿物→银的硫化物→银的自然金属。 相似文献
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S. Viswanathan K. Surya Prakash Rao B. Mahabaleswar 《Journal of the Geological Society of India》2013,82(6):621-627
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours. 相似文献
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E. M. Prasolov S. A. Sergeev B. V. Belyatsky E. S. Bogomolov K. A. Gruzdov I. N. Kapitonov R. Sh. Krymsky V. O. Khalenev 《Geochemistry International》2018,56(1):46-64
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others. 相似文献
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奥地利安东帕有限公司 《岩矿测试》2009,28(3):306-306
最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提 相似文献
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Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance. 相似文献
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Alexander E. C. Broberg J. S. Kehren A. R. Graziani M. M. Turri W. L. 《Environmental Geology》1993,22(4):353-361
Bellechester, Minnesota, is a small community of approximately 155 residents located on the county line between Goodhue and Wabasha counties in southeast Minnesota's karst region. Bellechester is served by a 21-year-old wastewater treatment facility (WWTF) consisting of three waste-stabilization ponds. On 28 April 1992 six sinkholes were discovered to have drained cell 2 of the WWTF resulting in the loss of approximately 8.7×106 1 of partially treated effluent and about 600 m3 of soil into previously undetected subsurface voids of unknown dimensions. In the week following the collapse, approximately 200 water wells located within a 5-km radius of the WWTF were sampled in an after-the-fact, emergency sampling program. Twelve samples with elevated fecal coliform levels, 18 samples with nitrate-nitrogen greater than the 10 mg/1 standard, and no samples with elevated chlorides were found. However, the elevated levels could not be unambiguously attributed to the WWTF collapse. This is the third WWTF to fail by sinkhole collapse in southeast Minnesota since 1974. All three collapsed lagoons have been located in similar geomorphic and stratigraphic settings. However, at least two lagoons have collapsed in the adjacent area in northeast Iowa, and these lagoons are located at different stratigraphic positions. Twenty-two WWTFs constructed in southeast Minnesota's karst region in the last 25 years have been identified as subject to potential sinkhole collapse. An unknown but significant number of manure storage lagoons, flood control structures, etc., have also been constructed in the karst region and are at risk. Public agencies are beginning to develop plans to deal with the risk associated with existing and future waste lagoons in this environment. The critical hydrogeologic parameters that can be used to prioritize the risk of collapse at existing facilities include: (1) the lithology of the first bedrock beneath each lagoon, (2) the thickness of surficial materials between the lagoon and the bedrock surface, (3) the presence and construction of liners (seepage rate), and (4) the proximity to existing sinkholes. 相似文献
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岩石密度和超高压岩石折返速率 总被引：1，自引：3，他引：1
在常温常压条件下对中国大陆科学钻CCSD主孔100-3000米岩心样品进行了密度测量,建立了密度连续剖面,并界定了不同超高压岩石的密度值。通过对比高温高压物性实验资料,岩石密度随着退变程度增强而降低,榴辉岩密度变化序列为3.52g/cm3→3.49g/cm3→3.07g/cm3→2.93g/cm3。超高压长英质岩石密度变化序列为3.00g/cm→2.80g/cm3→2.65g/cm3。上述实验资料是讨论不同折返阶段岩石所受浮力的基础,为研究折返速率大小提供了基本参数。本文通过折返板块运动平衡时,上浮力与粘滞力平衡这一关系式,定量研究了大陆俯冲板块的折返速率,认为密度差产生上浮力从而引起折返,温度对板块折返速率的影响最为显著;密度差大小、折返角度、折返板块大小对折返速率也有直接的影响。定量模拟分析表明,在温度高于850℃时,板块的折返速率可以超过100mm/a;当温度降至700℃时,折返速率则低于1.5mm/a。作者认为在折返早期,温度较高,板块快速折返至60-70km榴辉岩相深度;随着传导散热,温度降低,板块以较慢的速率折返至中下地壳。折返速率的估算表明,浮力是板块折返第一阶段(从>100km深部折返至<40km的中下地壳)的主要驱动力。 相似文献
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Mercury,arsenic, antimony,and selenium contents of sediment from the Kuskokwim River,Bethel, Alaska,USA 总被引：1，自引：0，他引：1
The Kuskokwim River at Bethel, Alaska, drains a major mercury-antimony metallogenic province in its upper reaches and tributaries. Bethel (population 4000) is situated on the Kuskokwim floodplain and also draws its water supply from wells located in river-deposited sediment. A boring through overbank and floodplain sediment has provided material to establish a baseline datum for sediment-hosted heavy metals. Mercury (total), arsenic, antimony, and selenium contents were determined; aluminum was also determined and used as normalizing factor. The contents of the heavy metals were relatively constant with depth and do not reflect any potential enrichment from upstream contaminant sources. 相似文献