首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
福建尤溪肖板金矿床金的赋存状态及金矿物特征   总被引:6,自引:0,他引:6  
肖板金矿床属受构造控制的中低温岩浆热液矿床,矿化类型为构造蚀变岩型。金多呈独立金矿物形式出现,少许呈分散状;金矿物以自然金为主,平均成色930,有少量银金矿和碲金矿。金矿物以包体金、裂隙金、连生金和粒间金等形式嵌布于黄铁矿、黄铜矿、石英、方铅矿及方解石等主要载金矿物中,且石英、方解石中较金属硫化物中占优势。金矿物形态各异,粒度以中细粒为主。  相似文献   

2.
广西田林县八渡金矿床主要产于辉绿岩侵入体中,广泛发育乳白色石英网脉,蚀变辉绿岩体即为金矿体,具有硅化、粘土化、碳酸盐化和硫化物化等卡林型金矿热液蚀变特征。本文采用电子探针(EPMA)背散射电子图像(BSE)、波谱(WDS)和能谱(EDS)分析技术,对该矿床原生矿石中含金硫化物显微岩相学结构以及主量和微量元素含量和分布规律进行了系统研究,认为金主要是以不可见化学结合态金(Au+)的形式赋存于含砷黄铁矿和毒砂之中。含金硫化物与热液交代形成的金红石密切共生,并保留含钛铁辉石或钛铁矿等矿物的假象,金红石的形成是辉绿岩中含钛铁辉石或钛铁矿热液蚀变的产物,含金硫化物形成所需要的Fe来自辉绿岩中含钛辉石或钛铁矿等矿物的溶解,Fe的硫化物化过程是导致含金硫化物形成的重要机制。  相似文献   

3.
为给砂宝斯金矿床的勘探和利用提供依据,本文总结了多年的野外观察资料,并通过镜下鉴定、人工重砂、电子探针等方法对该矿床的矿石矿物、金矿物特征进行了系统研究。结果表明,该矿床的矿石类型为贫硫化物微细粒浸染型金矿石,矿石矿物主要为黄铁矿,次为毒砂,含有较多的微量元素;脉石矿物主要为石英。矿石结构主要为半自形-自形、他形、交代、固溶体分离结构,浸染状或细脉浸染状构造。金矿物主要为自然金,其赋存状态以硫化物中包裹金和脉石粒间金为主,主要为微粒金及次显微金,呈微细分散状态。除Au元素外,矿床中其他元素均不具有综合利用价值,有害元素含量低。  相似文献   

4.
高凡金矿床是次火山热液型中低温金(银)矿床,对矿石中主要矿石矿物自然金、石英,黄铁矿,银矿物,闪锌矿,方铅矿和方解石等矿物标型性研究,得出了高凡金(银)矿床的矿物标型特征及空间分布规律,利用这些规律可指导该矿床深部的找矿工作及区域上同类型矿床的寻找。  相似文献   

5.
青海果洛龙洼金矿床金的赋存状态研究   总被引:3,自引:0,他引:3  
果洛龙洼金矿床物质组成简单,属少硫化物型,金属矿物含量约5.4%,脉石矿物含量约94.6%.载金矿物以石英和黄铁矿为主,金矿物有银金矿和自然金,在矿石中分布很不均匀,以裂隙金和粒间金为主要赋存形式.金矿物粒度较细.  相似文献   

6.
安徽铜陵鸡冠石银(金)矿床地质地球化学特征   总被引:4,自引:0,他引:4  
鸡冠石银(金)矿床是铜陵地区一个具中型规模的银(金)矿床,在整个长江中、下游地区都有其代表性。矿床分四个主要成矿阶段:夕卡岩阶段、氧化物-硫化物阶段、石英-硫化物阶段和石英多金属硫化物-碳酸盐阶段。对矿床的微量元素分析结果表明,独立的银、金矿物和含Au、Ag低的硫化物、含Ag硫盐矿物,主要形成于热液成矿期中晚阶段;矿床的轻、重稀土元素总深度比值与辉石二长闪长岩相近,反映出二者的同源特征;稳定同位素  相似文献   

7.
张志华 《地质与勘探》2018,54(S1):1416-1424
黑龙江省三道湾子金矿床是碲化物型低硫化浅成低温热液矿床,矿石类型主要为贫硫石英脉型,矿石矿物组合较简单,除了黄铁矿、黄铜矿以外,通过光薄片鉴定以及电子探针、扫描电镜分析,在矿脉中发现大量金银碲化物,主要有斜方碲金矿、针碲金银矿、碲金银矿、碲银矿等;脉石矿物有石英、方解石等,富含碲化物的地段往往是富矿囊的部位。三道湾子金矿床经历了四个成矿阶段:石英-黄铁矿阶段;石英-多金属硫化物阶段;石英-金、碲化物-硫化物阶段,为金矿脉的主体;石英-碳酸盐阶段。  相似文献   

8.
陕西小秦岭金矿床中金的赋存状态及分布规律   总被引:2,自引:0,他引:2  
陕西小秦岭脉状金矿床中,金的赋存状态及其分布与硫化物的发育程度密切相关,金优先赋存于硫化矿物中,只有当硫化物不发育时,才主要以金矿物形式赋存于石英等矿物中。金矿物的Ag/Au比率主要受成矿温度、硫化物发育程度、成矿热液中Cl/S浓度比值等因素制约。  相似文献   

9.
山西省阳高县堡子湾金矿床矿物标型特征   总被引:2,自引:0,他引:2  
根据成因矿物学及找矿矿物学观点,系统研究堡子湾金矿床黄铁矿、金矿物、方铅矿、黄铜矿和闪锌矿等金属矿物,石英、碳酸盐、绢(白)云母和金红石等非金属矿物的产状、形态及化学成分标型,结果表明:①矿床中矿物组合复杂,硫化物种类多,有少量硫盐矿物出现;②矿物中微量元素成分复杂,富含As,Sb,Bi,Se,Te等Au活化、迁移有利的矿化搬运剂,Cu,Ph,Zn,Au,Ag等成矿元素和Cr,Ni,V等深源元素;元素矿物组合及其特征比值指示金矿化与深源(下地壳或上地慢)浅成岩浆热液活动(斑岩系统)有关,燕山期石英二长斑岩(角砾岩)是成矿的主导因素;③矿石中大量出现铁白云石、富铁闪锌矿,粒状、富Ti金红石的大量分布,反映矿床剥蚀深度较大,目前可能已揭露至中深部中温带,位于斑岩系统的中下部,深部金矿化不利;④矿石含丰富的铜矿物,其他硫化物矿物中含铜量大,指示深部可能存在斑岩型Cu(Au)矿化。  相似文献   

10.
大王西峪金矿床位于大月坪复背斜南翼近轴部部位,属小秦岭金矿田的西(峪)—闵(峪)含金石英脉密集区。该矿床为岩浆热液成因的石英脉型金矿,矿石类型主要为金—黄铁矿—脉石英型和金—多金属硫化物—脉石英型。组成矿石的矿物成分较复杂,脉石矿物以石英为主,局部有绢云母、长石、绿泥石及碳酸盐矿物;金属矿物以黄铁矿为主,次有方铅矿、黄铜矿、磁铁矿和微量白钨矿、钼铅矿、泡铋矿、闪锌矿、自然金、银金矿等。次生矿物有褐铁矿、白铅矿、蓝辉铜矿、铅矾及孔雀石等。金的载体矿物主要为黄铁矿,次有方铅矿、黄铜矿、石英等,金以微细粒度的包体金、裂隙金、粒间金状态赋存于载体矿物晶体中。根据单矿物样品分析结果,金主要赋存在黄铁矿等金属硫化物中,故金主要富集在多金属硫化物—脉石英类型的矿石中。  相似文献   

11.
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   

12.
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   

13.
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   

14.
本文介绍样品经四硼酸锂熔融制成玻璃小饼。采用Lachance模式和理论a系数来校正元素间的效应,由3080E型X-射线荧光谱仪和DF-350B数据处理系统完成硅酸盐中十三个项目的测定。  相似文献   

15.
本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。  相似文献   

16.
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   

17.
18.
Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km2 and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world.  相似文献   

19.
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   

20.
《Applied Geochemistry》2001,16(2):137-159
Five hundred and ninety-eight samples of terrestrial moss (Hylocomium splendens and Pleurozium schreberi) collected from a 188,000 km2 area of the central Barents region (NE Norway, N Finland, NW Russia) were analysed by ICP-AES and ICP-MS. Analytical results for Al, B, Ba, Ca, K, La, Mg, Mn, Na, P, Rb, Si, Sr, Th, U and Y concentrations are reported here. Graphical methods of data analysis, such as geochemical maps, cumulative frequency diagrams, boxplots and scatterplots, are used to interpret the origin of the patterns for these elements. None of the elements reported here are emitted in significant amounts from the smelting industry on the Kola Peninsula. Despite the conventional view that moss chemistry reflects atmospheric element input, the nature of the underlying mineral substrate (regolith or bedrock) is found to have a considerable influence on moss composition for several elements. This influence of the chemistry of the mineral substrate can take place in a variety of ways. (1) It can be completely natural, reflecting the ability of higher plants to take up elements from deep soil horizons and shed them with litterfall onto the surface. (2) It can result from naturally increased soil dust input where vegetation is scarce due to harsh climatic conditions for instance. Alternatively, substrate influence can be enhanced by human activity, such as open-cast mining, creation of ‘technogenic deserts’, or handling, transport and storage of ore and ore products, all of which magnify the natural elemental flux from bedrock to ground vegetation. Seaspray is another natural process affecting moss composition in the area (Mg, Na), and this is most visible in the Norwegian part of the study area. Presence or absence of some plant species, e.g., lichens, seems to influence moss chemistry. This is shown by the low concentrations of B or K in moss on the Finnish and Norwegian side of the (fenced) border with Russia, contrasting with high concentrations on the other side (intensive reindeer husbandry west of the border has selectively depleted the lichen population).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号