滇缅腾冲-毛淡棉构造岩浆岩带钨锡成矿系统与典型矿床研究

本文在野外地质调查基础上,结合前人研究资料及部分项目研究成果,在分析研究腾冲-毛淡棉构造带的成矿地质背景、构造岩浆演化和主要钨锡矿床成因类型的基础上,探讨了构造岩浆演化与钨锡成矿系统的形成关系和花岗岩成矿作用.选取构造岩浆带内来利山和赫敏之两个典型岩浆热液型锡钨矿床,进行矿床特征、矿床成因、成矿成岩时代及构造背景的对比研究发现,腾冲-毛淡棉构造岩浆岩带可能具有统一的构造-岩浆-成矿演化系统,为一个燕山-喜山期形成的构造-岩浆-成矿带.这一认识对于指导该地区锡钨矿成矿预测和地质找矿工作具有重要意义.     

内蒙古苏尼特左旗乌日尼图钨钼矿床地质特征及找矿标志

乌日尼图钨钼矿床是近年来在国土资源大调查中发现的一个大型矿床.钨钼矿体主要产于燕山期细粒花岗岩与中下奥陶统乌宾敖包组砂板岩的外接触带中,矿体多呈脉状及透镜状,且明显受构造裂隙控制;矿床成矿在不同部位其矿化形式不同.在成矿母岩--燕山期细粒花岗岩中形成浸染状矿石;同时在与含钙质的板岩接触部位形成夕卡岩型矿石,在乌宾敖包组裂隙中形成热液脉型矿石.其中热液上侵与围岩接触处的细脉状矿床最为主要;矿体围岩蚀变发育,硅化、黄铁矿化与矿化关系最为密切;矿床深部钨钼矿石呈浸染状分布于细粒花岗岩中,后者为成矿母岩;矿床成因属广义的斑岩型矿床.     

甘肃省肃北县黑山梁钨钼矿床地质特征及成因探讨

黑山梁钨钼矿床,位于甘肃北山北部,是近年在甘肃北山地区新发现的矿床。矿床位于哈萨克斯坦板块的黄山—红石山—路井晚古生代陆内裂谷带北缘,处于红石山—黑鹰山断裂带中,钨钼矿化分布在扫子山组2段中的构造裂隙中,矿区圈出钨矿体148个、钼矿体4个,大致呈NEE向似层状、脉状分布,矿床的成因类型可能属中高温热液型。     

赣北石门寺超大型钨多金属矿床地质特征

赣北石门寺钨矿床为最近查明的大湖塘超大型钨矿床的北矿段。矿体呈似层状、筒状、脉状分布于燕山期酸性花岗岩体上部及与晋宁期黑云母花岗闪长岩外接触带附近。主要工业矿物为白钨矿、黑钨矿、黄铜矿、辉钼矿,矿石组构类型主要有交代结构、固溶体分离结构、脉状构造、浸染状构造及块状构造。常见围岩蚀变有碱性长石化、云英岩化、绿泥石化、硅化,矿床成因类型属岩浆期后热液型。根据矿体特征、矿物组合、矿石组构、矿化分带与围岩蚀变等方面的差异,又可将主要矿体划分为细脉浸染型、热液隐爆角砾岩型和石英大脉型。这3类矿体围绕燕山期酸性花岗岩体共生交织,形成了石门寺“一区三型”钨-铜-钼矿床。石门寺矿区黑云母花岗闪长岩中细脉浸染状白钨矿的发现,改变了以往只专注评价石英大脉型黑钨矿的找矿思路,为矿区及九岭矿集区实现钨矿找矿突破指明了新的方向。     

广西博白油麻坡钨钼矿床地质特征及找矿标志

广西博白县油麻坡钨钼矿区位于博白-岑溪铅锌钨锑金银多金属成矿带内,矿体产于泥盆系下统与花岗闪长斑岩接触的矽卡岩带中或黑云母花岗闪长斑岩、花岗压碎岩、绢云石英片岩中。根据以往勘查成果及综合研究,结合区域矿床对比,认为博白县油麻坡钨钼矿床属中-高温热液-矽卡岩型钨钼矿床和花岗闪长斑岩石英脉型辉钼矿床。该区具有良好的钨钼成矿条件和找矿前景。     

云南德钦县加仁铜矿矿床成因浅析

加仁铜矿位于羊拉-曲隆铜、铅、锌、银成矿带,该铜矿矿体严格受断裂构造破碎带控制,矿体的近矿围岩主要为印支期花岗闪长岩及燕山期二长花岗岩,属中低温热液交代-充填型脉状铜矿床。     

湘南黄沙坪铜锡多金属矿床构造控岩控矿机制及深部找矿勘查启示

黄沙坪铜锡多金属矿床是在钦杭成矿带和南岭成矿带叠合构造背景下形成的岩浆热液型多金属成矿系统的典型代表,该区铜多金属矿与锡多金属矿成矿系统复合、多期构造体系联合、深部钨锡矿与浅部铅锌银矿耦合等特点突出。针对该矿床控矿构造深部展布格局不清、深部铜锡多金属矿体定位不明的核心问题,基于矿田(床)构造精细解析,开展了多期构造体系控岩控矿作用机理及其控矿构造深延格局的深入研究,表明岩浆侵入接触构造系统与倒转背斜翼部的层间断裂-裂隙系统分别控制了脉状-不规则SK型铜钨锡多金属矿体群与沿NNE-NE向层间断裂带、NW向断裂带分布的热液脉型铅锌银(金)矿体群,这些矿体群具有不同的侧伏规律;基于矿田、矿床、矿体(脉)尺度控岩控矿构造组合样式的剖析,揭示了构造分级控岩控矿规律和中心对称成矿效应,厘清了成矿前、成矿期和成矿后构造体系,构建了矿田构造控岩控矿模式,进一步论证了坪宝矿田成矿构造动力学背景:中生代以来,坪宝矿田构造应力作用呈现“顺时针式”的运动方式,在燕山早期太平洋板块与华夏板块发生碰撞造山作用,在区内产生SEE-EW向主压应力作用,从而在矿田内形成了中酸性岩浆侵入成岩成矿系统。这些认识为坪宝矿田乃至钦杭、南岭成矿带湘南地区深部找矿勘查提供了重要启示。     

东昆仑祁漫塔格西段白干湖超大型钨锡矿田地质特征及其矿化交代岩分类

白干湖钨锡矿田位于东昆仑祁漫塔格西段新疆维吾尔自治区若羌县境内.笔者通过对柯可卡尔德、白干湖、巴什尔希和阿瓦尔4处矿床实地剖析,认为这些矿床已构成一个集矽卡岩型、云英岩化花岗岩微细网脉浸染型和石英脉型交代、充填叠加复合的具超大型远景规模的钨锡矿田.矿田内矿化类型显示出一定的分布规律或分带性:即产于花岗岩边部外接触带的矽卡岩型白钨矿矿体,呈透镜状或似层状分布在金水口群浅变质岩系大理岩内;产于花岗岩小突起内侧及其顶部外接触带伸枝脉岩的云英岩化花岗岩微细网脉浸染型钨锡矿体,前者呈厚板状透镜体面型分布,后者则呈脉状线型分布于围岩地层中;产于隐伏花岗岩突起上部外接触带的石英脉充填交代型锡石黑钨矿矿体,其因受区域NE向白干湖深大断裂构造限制,多呈低缓角度的平行脉状充填于金水口群浅变质岩系的绢云石英片岩中.根据矿石矿物组合等特征,矿田内的矿化蚀变可划分为3种:即矽卡岩化、云英岩化(包括钠长石化、电气石化等)和硅化.研究表明,矿田内矽卡岩型白钨矿化、云英岩化花岗岩微细网脉浸染型钨锡矿化和石英脉充填交代型锡石黑钨矿化构成一个与加里东期中细粒(似斑状)二长花岗岩侵入活动有成因联系的矿田成矿系列,属于岩浆期后高温-气化热液交代和中低温热液充填交代形成的产物.     

大湄公河次地区构造单元划分

大湄公河次地区在地质构造上是西南三江构造带和华南加里东褶皱带的向南或南西的延伸。在理清了各构造单元的延伸趋势及其相互关系的基础上，对该区大地构造单元作了统一划分和对比。以印缅山脉结合带、澜沧江-文冬-劳勿结合带、金沙江-哀牢山-马江结合带作为主结合带，将该区划分为印澳板块、中缅马陆块、印支陆块和华南陆块4个一级单元。然后在亲冈瓦纳的中缅马陆块和亲华南型的印支陆块内再以次级结合带分别划分出4个二级构造单元：亲冈瓦纳型的西缅微陆块、腾冲-毛淡棉微陆块，保山-掸泰微陆块、临沧-景栋微陆块，亲华南型的景洪-帕府-东马来西亚微陆块、思茅-大叻微陆块、昆嵩微陆块和长山微陆块；华南陆块以越北斋江结合带为界分为扬子和华夏两微陆块。简要论述了各构造单元的基本地质特征，提出将可可西里-澜沧江-文冬-劳勿结合带作为南部冈瓦纳大陆和北部劳亚大陆的分界，指出昆嵩微陆块和长山微陆块是华夏微陆块的南西延伸，其西部的对应体可能是昌都微陆块。     

内蒙古巴林左旗中段铅锌矿地质特征及成因

内蒙古巴林左旗中段铅锌矿位于大兴安岭成矿带中南段,西拉木伦成矿带北。矿体受EW向断层控制,因此发育有近EW向的构造蚀变带,矿石主要为绿帘石化绿泥石化蚀变岩,矿体主要呈脉状产出,赋存于早白垩世斑状正长花岗岩与谭家湾变质砂砾岩接触外带中。金属矿物以方铅矿、闪锌矿为主,次为黄铜矿、黄铁矿等,围岩蚀变主要有绿帘石化、绿泥石化、硅化。其成因为岩浆期后热液活动时期的构造蚀变岩型矿床,是岩浆期后含矿热液沿构造带充填-交代而成。找矿方向为早白垩世斑状正长花岗岩与变质地层的接触外带附近EW向构造有关的绿泥石绿帘石蚀变带。     

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.     

岩石密度和超高压岩石折返速率

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。     

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).