西藏西部日土县材玛铁多金属矿地质特征及找矿意义

以1:25万日土县幅区域地质调查成果为基础,论述了日土县材玛铁多金属矿的地质特征,并对其成因、找矿意义等进行了初步的讨论.结合尼雄铁矿及邻区找矿成果对比分析,认为白垩纪为西藏重要的富铁矿成矿期.材玛铁多金属矿是岩浆期后中低温热液矽卡岩型交代-充填矿床,该矿主要产于围岩(大理岩)中,矿体呈脉状、透镜状.该矿的发现为班公湖-怒江结合带两侧富铁矿找矿打开了一个窗口.     

西藏西部日土县材玛铁多金属矿地质特征及找矿意义

以1:25万日土县幅区域地质调查成果为基础,论述了日土县材玛铁多金属矿的地质特征,并对其成因、找矿意义等进行了初步的讨论.结合尼雄铁矿及邻区找矿成果对比分析,认为白垩纪为西藏重要的富铁矿成矿期.材玛铁多金属矿是岩浆期后中低温热液矽卡岩型交代-充填矿床,该矿主要产于围岩(大理岩)中,矿体呈脉状、透镜状.该矿的发现为班公湖-怒江结合带两侧富铁矿找矿打开了一个窗口.     

秘鲁邦沟铁多金属矿地质特征及成矿阶段划分

秘鲁首都利马至查拉400km沿海成矿带赋存多处铁、铜、金矿床,铜金矿床具有IOCG(铁氧化物)型,铁矿多为矽卡岩型。邦沟铁多金属矿规模巨大,矿床位于西科迪勒拉山西部边缘的伊卡-纳斯卡拗陷附近。矿床类型既有矽卡岩特征,也具有IOCG特点。总结矿床地质特征认为,邦沟铁和多金属矿矿化存在同期不同阶段的特点,铁矿化发生在第一期,铜金硫化物矿化发生在第二期;铜金硫化物在空间上与主铁矿体异位,铜金矿有较大找矿潜力。     

西藏日土地区弗野玢岩铁矿的地质特征及找矿意义

以西藏1∶25万羌多幅区域地质调查成果为基础,论述了日土县弗野铁矿的地质特征,并对其成因、找矿意义等进行了初步讨论。弗野岩体是一个以闪长玢岩为主的杂岩体,主要岩性为辉石石英闪长玢岩、花岗闪长玢岩、石英闪长玢岩。成矿围岩主要为大理岩。控矿因素主要有地层、构造、岩浆岩。铁矿成因属玢岩型。该铁矿主要产于岩体与围岩的外接触带及大理岩中,矿体呈脉状、透镜状。该铁矿的发现为在班公湖-怒江结合带两侧寻找富铁矿提供了新的线索。     

对阿勒泰富铁矿成矿区地质找矿的几点认识

阿勒泰富铁矿成矿区成矿地质条件与哈萨克斯坦矿区阿勒泰相似，据现有资料反映，已具备寻找中一大型铁及多金属矿的条件，因此在该区加强地质找矿，特别是运用综合方法找矿，可达到预期目的。     

福建省永定县大排铅锌矿的找矿思路创新和突破

福建永定县大排矿区是历经多次地质工作的老矿区,之前仅作为一个小锰矿在开采。本项目成功运用新理论正确指导找矿、运用新方法实施找矿,发现并基本查明该矿为一以铅锌矿为主,并共、伴生铁矿、铜矿、钼矿、银矿、锰矿等多种矿产的大型多金属矿床,矿种为浅部铅锌多金属矿经铜多金属至深部磁铁矿,成因类型为层控-矽卡岩型→层控-热液叠加改造型,该矿床的发现进一步丰富了区域矿床成因理论,拓展了区域找矿思路。     

中天山巴伦台-奎先达坂一带铅锌矿成矿地质特征及找矿前景

巴伦台-奎先达坂一带位于博罗科努金、铜、铅锌、铁矿带中,是中天山重要的成矿区带之一,带内发现铁、铅锌、铜矿(床)点数10处。以该区1∶5万化探普查、区域地质调查资料为基础,以发现的铁铅锌多金属矿初步评价成果为依据,总结了区域成矿分布规律、成矿地质背景、矿床地质特征、区域物化探并进行分析和对比,初步建立了巴伦台-奎先达坂一带主要矿床类型的找矿标志和综合地质找矿模型,为该地区寻找大中型铅锌矿床指出了方向。     

西藏林周县普琼朗铁矿地质特征及找矿方向

以在勒青拉及其邻区开展矿产资源大调查项目成果为基础,对林周县普琼朗铁矿的成矿地质背景、矿床地质特征、地球物理特征、矿床成因、找矿前景等,进行了比较详细地研究.结果表明,喜马拉雅早期为西藏冈底斯岛弧造山带重要的富铁矿成矿期,普琼朗铁矿是产于喜马拉雅早期居布札日花岗闪长岩围岩接触带中的,岩桨期后中低温热液矽卡岩型交代一充填矿床.该矿是产于花岗闪长岩围岩接触带的矽卡岩和矽卡岩化灰岩中的大型矿床,在矿区外围找矿潜力巨大.矿体呈脉状、透镜状、似层状.矿体产出部位严格受矿区二叠系洛巴堆组,蒙拉组碳酸盐岩层位及其层间破碎带,以及近东西向断层破碎带的控制.容矿岩石主要为二叠系洛巴堆组,蒙拉组矽卡岩、矽卡岩化灰岩.矿石矿物主要为磁铁矿,次为黄铜矿、蓝铜矿;脉石矿物主要为方解石、石英、透辉石、石榴子石等.在综合研究基础上,提出了主要找矿标志和找矿方向,为区内找矿突破提供了新思路和新资料.同时该矿的发现,为冈底斯岛弧造山带富铁矿找矿突破奠定了基础.     

青海西部祁漫塔格成矿带找矿新进展及其意义

青海省祁漫塔格成矿带位于东昆仑造山带北西段,带内以往开展了以铁为主的找矿工作,发现一批矽卡岩型中型矿床。近年来带内找矿取得了重大突破:①发现一种新类型矿床——"虎头崖"式层控型大型多金属矿床;②低缓磁异常区多金属和铁矿找矿效果显著,发现四角羊-牛苦头大型多金属矿床,野马泉矿区多金属矿规模达到中型,尕林格矿区发现深部厚大的铁矿体。在系统地综合总结这些成果的基础上,探讨了找矿新进展的意义,划分了3处成矿远景区,并初步讨论了各成矿远景区内进一步找矿的方向。     

老挝人民民主共和国万象省赛宋文县爬立山铁矿地质特征及找矿方向

本文以笔者在老挝人民民主共和国万象省赛宋文县爬立山铁矿区开展铁矿产资源勘查评价项目成果为基础,对爬立山铁矿的成矿地质背景、矿床地质特征、地球物理特征、矿床成因、找矿前景等进行了比较详细的研究.结果表明,华力西期为老挝川圹—长山构造带重要的富铁矿成矿期.爬立山铁矿产于华力西期花岗闪长岩与中—上泥盆统灰岩接触带矽卡岩中.矿区矽卡岩发育,已发现的10个原生铁矿体均赋存于花岗闪长岩体与灰岩接触交代形成的矽卡岩带中.矿体形态、产状的变化受矽卡岩体控制.爬立山铁矿为产于华力西期花岗闪长岩围岩接触带中的中高温热液矽卡岩型矿床.该矿为产于花岗闪长岩围岩接触带的矽卡岩、矽卡岩化砂岩和大理岩中的大型铁矿床.在矿区外围找矿潜力巨大.矿体呈脉状、透镜状、似层状.矿体产出部位严格受矿区泥盆系中上泥盆统碳酸盐岩、钙质砂岩层位及北东、北北西向及北西向断层破碎带的控制.容矿岩石主要为中—上泥盆统矽卡岩、矽卡岩化灰岩、大理岩和钙质砂岩.矿石矿物主要以磁铁矿、赤铁矿为主,次为褐铁矿及少量黄铜矿、黄铁矿;脉石矿物主要为方解石、石英、透辉石、透闪石、石榴子石、绿泥石、绿帘石等.研究表明碳酸盐岩地层、花岗闪长岩的侵入、北西向老挝川圹—长山构造带断层的多期次活动及其后期构造作用形成的北东向断层和东西向断层是区内矽卡岩型铁矿形成的重要控制因素.在综合研究成矿地质条件和磁异常特征的基础上,总结了主要找矿标志和找矿方向,提出矿区磁异常深部及外围尚有矽卡型铁矿找矿潜力.本文的研究成果为区内找矿突破提供了新思路和新资料.为老挝川圹—长山成矿带富铁矿找矿突破奠定了基础.     

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.     

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。     

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.     

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.     

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。     

Bellechester,Minnesota, USA,lagoon collapses

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.     

Mercury,arsenic, antimony,and selenium contents of sediment from the Kuskokwim River,Bethel, Alaska,USA

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.     

滇东南花岗岩与锡、银、铜、铅、锌多金属矿床的成因关系

滇东南锡、银、铅、锌多金属矿床主要分布在个旧、白牛厂、都龙3个矿区,而滇东南较大的3个花岗岩体又分别出露在3个矿区或附近.花岗岩体均形成于燕山晚期,岩石化学、矿物成分相似,富含锡、银、铅、锌、钨、铜等成矿元素.矿床主金属元素组合与岩体之间的距离由远而近出现由锡、钨、(铍、铌、钽)→锡、钨、(铁)、铜、铟→锡、铅、锌、银、铟、(锑)有规律的变化.花岗岩浆是成矿物质来源和成矿热源.岩浆侵入初期使上覆地层隆起产生背斜(凹陷部位成向斜);同时使地层产生一系列裂隙、压性断层或层间断裂;岩浆侵入晚期,这些断层再次活动,表现为张性,岩浆产生的含矿热液沿由其活动所造成的断裂迁移、充填、交代、沉淀而形成矿床.     

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。