西藏弄如日金矿流体包裹体研究

弄如日金矿床位于青藏高原南部冈底斯-喜马拉雅构造区的冈底斯构造岩浆带东段,是该成矿带上首次发现的浅成低温热液型金锑矿床。本文在详细的野外矿床地质研究基础上,通过对各期与成矿密切相关的流体包裹体岩相学、显微测温分析、包裹体成分的LRM分析和包裹体中子矿物相的SEM/EDS分析等,对与矿化有关的成矿流体的特征、演化以及金的迁移与沉淀机制进行了讨论。通过研究流体成矿过程包括:形成黄铁矿-石英组合的早期阶段,发育以含子矿物的三相包裹体为主,均一温度集中于256~335℃,盐度29.7%~38.9% NaCleqv;形成毒砂-富砷黄铁矿-石英组合的主成矿阶段,发育富CO₂包裹体,均一温度集中于230~357℃,盐度1.81%~9.74% NaCleqv,CO₂密度为0.16~0.29g·cm^-3;形成辉锑矿-石英、雄黄-石英和碳酸岩脉组合的晚期阶段,发育水溶液包裹体,均一温度集中于134~245℃,盐度1.91%~8.95% NaCleqv。与金成矿有关的流体为中温、低盐度的富CO₂、CH₄、N₂、Na⁺流体体系,成矿流体温度、压力降低造成了流体不混溶,使CO₂相与水溶液相分离是造成金沉淀的主要机制。     

四川冕宁木落稀土矿床稀土矿物中富CO2和H2流体包裹体研究

木落稀土矿床位于四川省冕宁县境内，其成矿与喜山期岩浆碳酸岩有关。通过对矿床中主要稀土矿物氟碳铈矿中流体包裹体的岩相学、包裹体显微测温分析和包裹体成分的LRM分析等，对成矿流体的特征、演化及稀土矿化过程进行了讨论，结果表明与稀土成矿有关的流体为富CO₂和SO₂ 的中高温、高压超临界流体。温度、压力降低和流体不混溶是造成稀土矿物沉淀的主要机制。     

黑龙江多宝山斑岩铜(钼)矿床蚀变-矿化阶段及其流体演化

黑龙江多宝山斑岩铜(钼)矿床是大兴安岭中北部多宝山-阿尔山铜(钼)成矿带内最大的斑岩型矿床,位于兴蒙造山带的最东端。矿床赋存于花岗闪长岩及多宝山组下部地层中。据野外脉体类型和穿插关系、围岩蚀变类型、矿物组合,将多宝山斑岩铜(钼)矿床的蚀变和矿化自早至晚划分为4个阶段:Ⅰ钾硅化阶段;Ⅱ 硅化-钼矿化阶段;Ⅲ绢英岩化-铜矿化阶段;Ⅳ碳酸盐石英阶段。石英中包裹体类型主要有水溶液包裹体、富CO₂包裹体、含子晶多相包裹体、纯CO₂包裹体。成矿流体从早阶段到晚阶段具有规律性演化特征:钾硅化阶段发育水溶液包裹体、富CO₂包裹体,盐度集中在6%~10% NaCleqv,密度0.5~0.9g·cm^-3,均一温度峰值为245~400℃;硅化-钼矿化阶段发育水溶液包裹体、富CO₂包裹体、含子晶多相包裹体均一温度峰值为260~300℃,盐度1.7%~39% NaCleqv,密度0.3~1.1g·cm^-3;绢英岩化-铜矿化阶段发育水溶液包裹体、富CO₂包裹体,均一温度峰值220~280℃,盐度0.1%~24.8% NaCleqv,峰值集中在6%~12%,密度0.5~1.0g·cm^-3;碳酸盐阶段仅发育水溶液包裹体包裹体,均一温度峰值为125~170℃,盐度0.5%~12.8% NaCleqv,密度0.8~0.9g·cm^-3。激光拉曼探针分析结果表明成分主要为H₂O和CO₂。本文对多宝山矿床主成矿期压力进行了估算,Ⅰ、Ⅱ、Ⅲ阶段捕获压力分别为110~160MPa、58~80MPa、8~17MPa。测温实验结合野外现象及包裹体岩相学表明多宝山斑岩铜(钼)矿床是一个复杂的构造-岩浆成矿系统,与成矿有关的热流体不是单一的岩浆分异的结果,构造裂隙系统也为含矿流体提供了很好的导矿与容矿空间,矿床沉淀机制为温度压力的变化及空间的开放导致流体不混溶与沸腾作用,不同流体的混合、水岩反应致使流体pH值、成分发生变化,从而导致铜、钼的矿化。     

准噶尔北部希勒库都克斑岩钼铜矿床地质与成矿流体

希勒库都克斑岩铜钼矿床铜钼矿化与安山玢岩脉、英安玢岩脉有关,蚀变有钾长石化、绢云母化、绿帘石化等,向外发育绿泥石化、深部发育夕卡岩型蚀变。浅部以钼矿化为主,向深部铜钼矿化并存。与典型的斑岩型矿床相比,其石英中流体包裹体少而小,气体包裹体少,含CO₂包裹体及含子矿物包裹体发育,子矿物以NaCl为主,基本不出现KCl子矿物。钼富集处出现了富CO₂流体的沸腾,铜富集处出现了成群分布的含大子矿物包裹体,沸腾消失。钼的成矿主要与富CO₂成矿流体沸腾及斑岩型蚀变和夕卡岩蚀变有关,钼主要源于地壳,成矿温度为280~530℃,集中在300~400℃左右。铜主要与直接从深源基性岩浆出溶的高盐度流体及夕卡岩型蚀变有关,铜主要源于上地幔,主要成矿温度低于350℃。晚期流体的成矿温度为180~300℃左右。希勒库都克矿床成矿流体特征反映了壳源与幔源流体混合、岩浆热液与天水混合的特征。     

西秦岭铧厂沟金矿床流体包裹体特征研究及矿床成因

铧厂沟金矿位于西秦岭勉略缝合带南侧,其产出受韧脆性剪切带控制,赋矿围岩为泥盆系细碧岩、凝灰质绢云千枚岩和灰岩。根据脉体穿切关系和矿物交代关系,可以将铧厂沟金矿分为早、中、晚3个成矿阶段。在铧厂沟金矿的石英中发育了CO₂-H₂O型、纯CO₂型、H₂O溶液型和含子矿物型四种类型流体包裹体。早期石英中原生包裹体主要是CO₂-H₂O型和纯CO₂型,其成分为CO₂+H₂O±N₂±CH₄±H₂S,均一温度集中在320~360℃,盐度为0.43%~5.14% NaCleqv;中阶段为主成矿阶段,该阶段石英中包含了所有四种类型的包裹体,其中H₂O溶液型包裹体占了大多数,CO₂-H₂O和水溶液包裹体均一温度集中在240~320℃,盐度为0.43%~11.19% NaCleqv;晚阶段石英仅发育水溶液型包裹体,具有较低的均一温度(118~228℃)和盐度(0.18%~6.59% NaCleqv)。根据CO₂-H₂O型包裹体计算主成矿阶段压力为70~195MPa,成矿深度为5~7km。总体而言,铧厂沟金矿的初始流体具有中高温、富CO₂、低盐度的变质流体特征,晚成矿阶段流体演化为低温、低盐度水溶液流体,流体的不混溶导致了主成矿期的矿质的大量沉淀,铧厂金矿为中浅成的造山型矿床。     

首例独立碲矿床流体包裹体研究

四川石棉大水沟碲矿床是世界首例独立碲多金属矿床。包裹体的相态和成分特征表明,矿石和变质分异脉体富含CO₂、CO₂-H₂O(低盐度流体)和CO₂-H₂O-NaCl(高盐度流体)三种体系的流体包裹体,成矿作用与前两种体系的流体有关。薄片中普遍存在包裹体的自然爆裂现象,大多数包裹体在均一前发生泄漏或爆裂。矿物温度计表明,磁黄铁矿阶段成矿温度约500℃, 辉碲铋矿阶段约400℃ ,流体密度变化在1.04~0.76 g/cm³之间,成矿压力分别为450~500 MPa和240~300 MPa,矿化是在高温高压条件下发生的。     

内蒙古西拉木伦成矿带劳家沟斑岩型钼矿流体 包裹体特征及地质意义

[摘 要]劳家沟钼矿是西拉木伦成矿带东段阿鲁科尔沁旗天山镇新发现的一个斑岩型钼矿床。矿床赋矿岩石为中细粒斑状二长花岗岩,矿化类型以细脉状和浸染状辉钼矿为主。成矿过程包括早阶段(石英-辉钼矿-黄铁矿组合)、中阶段(石英-多金属硫化物组合) 和晚阶段(石英-方解石组合) 三个阶段。早阶段的石英细脉中发育气相水包裹体(PV)、液相水包裹体(PL)、CO₂-H₂O 三相包裹体( C)、富液相水溶液包裹体(L)、富气相水溶液包裹体(V)和含子矿物多相包裹体(S),子矿物包括石盐、硬石 膏及其它不明矿物;中阶段较早阶段除缺少CO₂三相包裹体外,其它相似;而晚阶段的石英-方解石细脉中流体包裹体发育较少,且类型单一,只有L 类和少量V 类。流体包裹体岩相学、显微测温及单个包裹体激光拉曼光谱分析结果表明劳家沟斑岩钼矿的成矿流体是以高温、高盐度、高氧逸度和含CO₂为特征的岩浆热液型流体,从早到晚其演化规律为:早阶段高温(320～>550℃)、高盐度(6～16wt% NaCleqv、52. 89～>66. 75wt% NaCleqv)、高氧逸度、富CO₂→中阶段中高温(280～>550℃)、高盐度(5～>15wt%NaCleqv、>66. 75wt%NaCleqv)、含CO₂→晚阶段中低温(160～250℃)、低盐度(0. 5～5 wt% NaCleqv)、贫CO₂。利用含石盐子晶包裹体的气液均一温度Th_L-V、石盐消失温度Tm_halite 和压力三者之间的关系对其最小捕获压力进行估算,结果显示成矿深度大约为5～7 km。根据区域成矿规律推测劳家沟斑岩钼矿的成矿时间大致为早白垩世,成矿构造背景对应于中国东部岩石圈强烈减薄。本文将劳家沟斑岩钼矿的成矿机制大致概括为:岩石圈强烈减薄诱发岩浆侵入活动,岩浆在侵入晚期发生液态不混溶作用形成高温、高盐度、高氧逸度、含CO₂的含矿气水热液,在地壳快速抬升期间流体多次减压沸腾,导致成矿物质沉淀。     

新疆乔尕山金矿成矿流体地质作用特征

新疆乔尕山金矿与韧性剪切带有关,主要有四个矿化阶段。本文通过矿物中包裹体研究,系统测定了本区不同类型金矿成矿物理化学条件,其中流体体系具有富CO₂的特征,熔融包亵体均一温度达900~1100℃ ,气液包裹体均一温度为240~400℃ ,确定成矿流体体系为Na⁺-K⁺-SO₄^2--HCO₃^--H₂O; 区分了矿床南段及北段包裹体特征,并查明金矿中包裹体的找矿标志。     

基于成矿流体包裹体的勘探——以柴北缘鱼卡造山型金矿为例

鱼卡金矿成矿流体的包裹体以富液相的气液两相（不同的CO₂和H₂O比）包裹体为主,属于中深层成矿环境的中低温造山型金矿。在综合分析鱼卡金矿的矿床地质特征基础上,从成矿流体包裹体的运移角度出发,通过成矿流体的物理化学参数变化以及流体包裹体面分析认为矿体的形成和空间分布受流体输导系统的控制;鱼卡金矿成矿流体总体从南东向北西运移,局部发生侧向运移,流体中心具有高温多期的特征;钻探施工证实矿体具有向南东侧伏的情况,成矿流体中心位于矿区南东部,即表明基于成矿流体包裹体研究指导金矿床的勘探工作有效。     

河南省东沟超大型钼矿床流体包裹体研究

河南省东沟钼矿床是东秦岭钼矿带新发现的燕山期超大型斑岩钼矿床,是大陆碰撞成矿理论预测在先,勘查突破在后的成功范例。该矿床的形成与东沟A型花岗斑岩有关,矿体产于斑岩体外接触带的熊耳群火山岩中。以岩体为中心发育典型的斑岩蚀变分带,由内到外依次是钾化、绢英岩化和青磐岩化。流体成矿过程包括早、中、晚3个阶段,分别以石英-钾长石组合、石英-(钾长石)-多金属硫化物组合和石英-碳酸盐-萤石组合为标志,矿石矿物主要沉淀于中阶段。早、中阶段热液石英中发育CO₂-H₂O型包裹体(C型)、水溶液包裹体(W型)和含子晶多相包裹体(S型),但晚阶段只发育水溶液包裹体(W型)。早阶段C型和W型包裹体均一温度集中于380~550℃,盐度为7.70%~18.28% NaCleqv;S型包裹体中常见石盐、黄铜矿、方解石和未知透明子矿物,其均一温度范围为318~516℃,加热过程中除石盐外其他子矿物不熔;不包括不熔子矿物的贡献,该类包裹体盐度变化于12.85%~17.87 和35.55%~47.67% NaCleqv。中阶段C型和W型流体包裹体均一温度集中于260~410℃,盐度为4.62%~18.28% NaCleqv;除不熔子矿物外,S型包裹体均一温度为197~436℃,盐度变化于7.45%~19.30% NaCleqv和31.71%~49.22% NaCleqv。晚阶段流体包裹体均一温度集中于125~225℃,盐度介于0.5%~7.25% NaCleqv之间。估算的早、中阶段流体捕获压力分别为63~117MPa和12~67MPa,推测最大成矿深度为4.7km。上述流体包裹体研究表明成矿流体由早阶段高温、富CO₂的岩浆热液演化为晚阶段低温、贫CO₂的大气降水热液。这种高温、富CO₂的岩浆热液可视为大陆内部体制斑岩成矿系统的标志性特征,以区别于岩浆弧区同类矿床高温、贫CO₂的岩浆热液。通过对比东秦岭-大别钼矿带典型斑岩成矿系统,认为成矿流体中CO₂等挥发组分的含量和围岩性质(化学成分、结晶程度、抗剪抗压程度等)是控制矿体空间定位的重要因素。     

Wavelength-dispersive X-ray fluorescence spectrometric determination of Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites

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.     

高压微波消解法测定醋酸纤维过滤器采集的微尘粒子中的砷镉钴铬铜铁锰镍铅钒锌

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     

Isotopic systematics of He,Ar, S,Cu, Ni,Re, Os,Pb, U,Sm, Nd,Rb, Sr,Lu, and Hf in the rocks and ores of the Norilsk deposits

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.     

硅酸盐中铁、锰、钛、钙、钾、磷、硅、铝、镁、钠、锶、铷、钡的X-射线荧光光谱定量测定

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。     

硅酸盐类样品中硅、铁、铝、钛、锰、钙、镁、钾、钠和磷的x射线荧光光谱测定

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。     

Viscous, cohesive, non-Newtonian, depositing, radial slurry flow

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.     

Mountains,nations, parks,and conservation

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.     

Regional distribution of Al,B, Ba,Ca, K,La, Mg,Mn, Na,P, Rb,Si, Sr,Th, U and Y in terrestrial moss within a 188,000 km2 area of the central Barents region: influence of geology,seaspray and human activity

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).     

NEW SET OF LOW CONCENTRATION STANDARDS FOR LA, CE, SM, YB, LU, Y, SC, V, NB AND TA IN SILICATES

We have developed a set of four synthetic standards for the rare earth and high field strength elements designed for use in the determination of those elements in silicates. The base material is a glass nominally at the eutectic of the MgO-Al₂O₃-SiO₂ ternary system. The nominal doping level was 2 wt% of the elements as oxides. To avoid problems associated with peak interference, the elements were doped in four separate glasses.