内蒙古干珠尔善德银铅锌矿床的短波红外光谱研究

内蒙古干珠尔善德银铅锌矿床是一处构造裂隙充填型脉状矿床,其围岩蚀变作用强烈,伊利石-绢云母类蚀变矿物广泛发育于围岩中,与银铅锌矿化作用密切相关。对围岩开展短波红外光谱测量,可以计算蒙脱石-伊利石-绢云母类矿物的伊利石结晶度(SWIR-IC),从而定量地确定该类蚀变作用的强度。该方法有效性试验研究表明,SWIR-IC与(Pb+Zn)%的品位具有很好的正相关关系,即围岩的伊利石-绢云母化蚀变作用越强,铅锌矿化作用也越强。通过对干珠尔善德详查区进一步开展短波红外光谱测量,在地表圈出了5处规模较大的SWIR-IC异常(IC1~IC5),其中IC1和IC4异常与银铅锌矿化带的位置相一致,IC5则可以作为下一步找矿的靶区。在热液脉状银铅锌矿床的勘查工作中,对围岩开展系统的短波红外光谱测量工作,可以定量地显示伊利石-绢云母化蚀变的强度,指示热液活动中心,从而寻找银铅锌矿体的所在,但需同时确认绢云母是否为热液蚀变成因。     

西藏努日铜多金属矿床蚀变矿物的近红外光谱学研究

西藏努日大型铜多金属矿床蚀变作用强烈,主要蚀变类型包括绿泥石化、绢云母化、绿帘石化等。其中,绿泥石—绢云母类蚀变与深部斑岩体热液矿化作用密切相关。通过对20个钻孔岩心开展系统的近红外光谱测量,准确地鉴定了蚀变矿物类型、近红外性质,计算了样品白云母族矿物结晶度指数等,定量地研究了蚀变作用的强度。结果表明,绿泥石光谱波长值与铜钨钼矿化呈一定的正相关性,其中铁镁绿泥石与成矿关系密切;白云母族矿物光谱波长值与铜钨钼矿化呈一定的负相关性,其中钠云母与成矿关系明显;钠云母光谱结晶度指数越大,矿物形成温度越高,越接近含矿热液活动中心,矿化作用越强。在今后努日矿区深部寻找斑岩型矿床的找矿勘查中,应系统地开展近红外光谱测量,准确鉴别蚀变矿物、结合结晶度指数的指标来判断含矿热液活动中心,以指导勘查工程的布设。     

德兴斑岩铜矿田两类伊利石的存在及其在蚀变分带中的意义

德兴斑岩铜矿田内存在两种成因类型的伊利石：一是特征的热液蚀变矿物,它是在热液流体 作用过程中斜长石、云母类矿物通过伊利石化过程形成的,其结晶度(IC)和膨胀层含量受携 带矿质的热液流体量控制;二是浅变质作用自身的产物,其结晶度远较小于前者,具2M1 多型,且不含膨胀层,是原始蒙皂石完全伊利石化形成的。作者发现,在斑岩体和接触带内 ,伊利石结晶度小的部位,蚀变程度强,矿化品位也高。     

河北省灵寿县秋树林钼矿床成矿条件分析及找矿标志

秋树林钼矿是阜平地区新发现典型的斑岩型钼矿,矿体主要赋存于花岗斑岩体破碎带内,受隐伏岩体和构造控制。围岩蚀变主要有硅化、钾长石化、黄铁矿化等,具典型斑岩型钼矿床的矿化和围岩蚀变特征。其中硅化和钾化与钼成矿关系密切。蚀变作用的强弱与钼矿体的品位高低相对应,硅化与钾化为该区最直接的找矿标志之一。     

大别山北麓姚冲钼矿床地质特征及找矿标志

河南省新县姚冲钼矿床是大别山北麓新发现的又一典型的斑岩型钼矿床,目前控制规模为中型。矿体主要赋存于花岗斑岩体(脉)外接触带(中元古界蚀变片麻岩),受隐伏岩体和构造控制。辉钼矿化呈浸染状、细脉-网脉状、薄膜状和角砾状产出。围岩蚀变主要有硅化、钾长石化、黄铁矿化、绢云母化、绿泥石化、绿帘石化、方解石化、萤石化和高岭土化等,具典型斑岩型钼矿床的矿化和围岩蚀变特征。其中硅化和钾长石化与钼成矿关系密切。矿床蚀变分带明显,由中心向外侧依次为钾长石化-硅化带(强蚀变带)、硅化-绢英岩化带(弱蚀变带)、硅化-青磐岩化带,由中心向外围蚀变强度逐渐变弱。蚀变作用的强弱与钼矿体的品位高低相对应,硅化和钾化为该区最直接的找矿标志之一。     

福建省铁帽山钼矿床地质、地球化学异常特征与找矿方向研究

福建铁帽山钼矿床位于闽西南拗陷带,是一个与晚侏罗世中酸性侵入岩有关的斑岩型钼矿床。矿体产出于花岗杂岩体中,杂岩体由中粗粒二长花岗岩、中粗粒钾长花岗岩、花岗斑岩和少量石英闪长岩组成,钼矿体围绕着矿区中部的花岗斑岩岩株近似呈环状分布,主要赋存于蚀变的二长花岗岩中。矿体受到后期断裂构造的破坏而被截断。矿区的围岩蚀变作用强烈,并具有明显的分带特征,自下而上、由内到外可划分为钾化带、石英-伊利石化带、蒙脱石化带和高岭石化带。其中,石英-伊利石化作用与钼矿化作用的关系最为密切。土壤地球化学测量结果显示,Mo元素对数值的频率统计呈双峰式分布,异常下限为12.2×10–6,由此圈定的Mo元素异常近似呈环状分布,与矿体分布范围总体上相一致;而低温成矿元素Zn、Ag元素和高温成矿元素Sn的异常多数分布于Mo元素环状异常的外围和中心低值区。在勘查工作中,石英-伊利石化蚀变和Mo元素地球化学异常可以作为最重要的找矿标志,同时要特别注意断层对矿体的截断和破坏作用。     

高硫-低硫化浅成低温热液矿床的短波红外矿物分布特征及找矿模型

本文以铁格隆南(荣那矿段)高硫化浅成低温热液矿床和斯弄多低硫化浅成低温热液矿床为研究对象, 运用短波红外技术快速厘定了上述两个矿床的蚀变矿物类型及组合特征, 构建了基于短波红外勘查技术的找矿模型。研究发现: 铁格隆南矿床(荣那矿段)的蚀变矿物垂向分带组合为: 高岭石→高岭石+(地开石+明矾石)→高岭石+明矾石+(地开石)→高岭石+地开石+明矾石。由于高硫化浅成低温热液交代黄铁绢英岩化带的斑岩型矿体, 致使上部矿石中还有少量交代残余的绢云母; 斯弄多低硫化浅成低温热液矿床的蚀变矿物垂向分布为: 白(绢)云母+(钠云母)→白(绢)云母+钠云母+(伊利石)→白(绢)云母+钠云母+蒙脱石+伊利石→白(绢)云母+钠白云母+蒙脱石+伊利石, 其中顶部白(绢)云母是后期黑云母花岗斑岩蚀变所产生, 本身与成矿无关; 矿体主要赋存在伊利石+蒙脱石带, 随着蒙脱石被伊利石化, 矿体也逐渐尖灭。     

高硫-低硫化浅成低温热液矿床的短波红外矿物分布特征及找矿模型——以西藏铁格隆南(荣那矿段)、斯弄多矿床为例

本文以铁格隆南(荣那矿段)高硫化浅成低温热液矿床和斯弄多低硫化浅成低温热液矿床为研究对象,运用短波红外技术快速厘定了上述两个矿床的蚀变矿物类型及组合特征,构建了基于短波红外勘查技术的找矿模型。研究发现:铁格隆南矿床(荣那矿段)的蚀变矿物垂向分带组合为:高岭石→高岭石+(地开石+明矾石)→高岭石+明矾石+(地开石)→高岭石+地开石+明矾石。由于高硫化浅成低温热液交代黄铁绢英岩化带的斑岩型矿体,致使上部矿石中还有少量交代残余的绢云母;斯弄多低硫化浅成低温热液矿床的蚀变矿物垂向分布为:白(绢)云母+(钠云母)→白(绢)云母+钠云母+(伊利石)→白(绢)云母+钠云母+蒙脱石+伊利石→白(绢)云母+钠白云母+蒙脱石+伊利石,其中顶部白(绢)云母是后期黑云母花岗斑岩蚀变所产生,本身与成矿无关;矿体主要赋存在伊利石+蒙脱石带,随着蒙脱石被伊利石化,矿体也逐渐尖灭。     

短波红外光谱技术在西藏尼木地区岗讲斑岩铜-钼矿床中的应用

为进一步探明岗讲斑岩铜-钼矿床蚀变和矿化结构,有效指导下一步勘查工作,利用短波红外光谱技术对矿床内典型剖面上的4个钻孔进行了系统的测试分析.共检测到绢云母类、高岭石类、绿泥石类、硫酸盐类和碳酸盐类等蚀变矿物,其中尤以绢云母类矿物最为发育.对绢云母进行短波红外光谱测试分析显示:在靠近矿体的位置,有较大的伊利石结晶度(≥1.5)和较小的绢云母Al-OH吸收位置(≤2 205 nm);而在远离矿体的位置伊利石结晶度和绢云母Al-OH吸收位置分别为0.8~1.2和2 207~2 209 nm.同时,铁氧化物强度值与氧化矿体的出现具有同步性.表明短波红外光谱的这些特征参数有助于进一步理解岗讲斑岩铜-钼矿床蚀变和矿化结构,有效识别成矿流体性质,有潜力成为该矿区及其他类似矿区有效的找矿指标.     

新疆温泉县北达巴特斑岩铜钼矿的蚀变带划分

北达巴特铜钼矿赋存于酸性次火山．浅成斑岩体中，其矿化作用呈上铜下钼的双层矿化结构模式。蚀变作用可划分为二期：早期蚀变作用发生在主成矿期之前，表现为黑云母化和钾长石化；晚期蚀变作用与铜钼矿化关系密切，主要表现为硅化、绢云母化、水白云母化、伊利石化、萤石化、电气石化及绿帘石化等，其成因类型可确认为斑岩型铜钼矿．     

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。