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在火成角岩与成矿关系的研究中,着重研究角砾岩体与其主岩体和矿化体之间的关系,提出在华南花岗岩中,诱发火成角砾岩的主岩体几乎全是ＩＩＩ阶花岗岩小岩体,火成角砾岩与成矿的关系其实质是高位小岩体与成矿的关系。根据角砾岩的形成条件可寻找岩浆源和二重源矿产。提出了火成砾岩的找矿指示作用和判别准则。 相似文献
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黔西南簸箕田金矿床位于灰家堡背斜矿田东段,是近年发现的近超大型卡林型金矿床。本文以发育在簸箕田金矿区的皂矾山矿段角砾岩为研究对象,通过详细的钻孔岩心观察,结合矿区以往基础地质信息,分析了角砾岩的产状、岩石学特征及其与成矿的关系。研究显示：皂矾山角砾岩为构造角砾岩,并分为构造热液角砾岩和构造破裂角砾岩两种类型;矿床的成矿阶段包括石英-白云石、自然金-黄铁矿-毒砂、雌雄黄-辰砂-石英-方解石3个阶段。总结了簸箕田金矿床的成矿过程,首先是形成灰家堡背斜,其次是形成皂矾山含矿构造角砾岩,最后是含矿热液运移、成矿物质萃取及矿体的形成。构建了簸箕田金矿“两富两贫”的成矿模式：距离皂矾山构造角砾岩筒中心带越近,矿体越富,距离构造角砾岩筒中心带越远,矿体越贫;越产在角砾岩筒及其两侧的深部位置的矿体越富,越产在角砾岩筒及其两侧的上部位置的矿体越贫。 相似文献
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通过火成角砾岩产地的调查和研究,认为武夷山火成角砾岩区成矿作用与高位岩浆活动有关,并据此筛选出火成角砾岩的产出条件（构造、地层、岩浆岩）作为成矿堆积的地质前提,提出（非通常意义）成矿预测指导思想和地质准则。 相似文献
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文章阐述隐爆角砾岩型金矿床的定义、成矿构造背景、隐爆角砾岩及其矿床特征、成矿流体特征以及隐爆角砾岩成岩-成矿模式等方面研究进展。隐爆角砾岩型金矿床多产于古老地块活化区、中生代断陷盆地边缘、滨太平洋岛弧火山岩带内。矿体与浅成-超浅成中-酸性斑岩具有密切的时空关系,多赋存于斑岩体的顶部。侵入岩具有富碱、富硅特征,属Ⅰ型花岗岩类。当侵入体顶部高热能流体压力大于围岩抗拉强度和最小主应力之和时发生隐爆作用而形成隐爆角砾岩。隐爆角砾岩筒垂向可分为裂隙相、震碎相、爆破相和通道相;角砾粒径从中心到边缘水平分带一般呈由小到大的趋势。成矿流体由于爆发作用瞬间由封闭体系进入半开放或开放体系,产生较大的压力梯度,流体减压沸腾、混合、不混溶和水岩反应等引起成矿元素稳定的物理化学条件变化,导致金络合物的溶解度降低而产生金矿化。隐爆角砾岩筒的形成及流体演化分别具有"自下而上-顺次推进-序次叠加"和"升温-(爆破)沸腾-降温-升温-(爆破)沸腾-降温"的演化过程,其中"沸腾-降温"阶段为矿质主要沉淀阶段。隐爆角砾岩型金矿的成矿具有"一体多型""一筒多型"的特点,运用矿床系列-成矿系统理论指导勘探找矿具有十分重要的意义。 相似文献
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康家湾硅化角砾岩天然热释光特征及对找矿的指导意义 总被引：1，自引：0，他引：1
通过对康家湾Ｐｂ、Ｚｎ、Ａｇ矿床的含矿带硅化角砾岩带进行天然热释光分析。发现其热释光特征与成矿有密切的关系,从而划分出了成矿的远景区。 相似文献
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柴窝堡铜矿区的层状铜矿属层间水压角砾岩控制的铜矿,脉状铜矿属高角度水力断裂控制的铜矿。首次在杏树沟发现产于石英钠长斑岩脉中的铜矿,并鉴别出铜沟控制Ⅰ号矿体的成矿构造为热泉通道。上述４类成矿构造分属岩浆成矿构造系列与水压成矿构造系列。建立的成矿构造模式表明深部具有很好的找铜前景。 相似文献
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《地学前缘》2017,(5):54-61
江西银坑矿田位于南岭—武夷山—赣东北三大成矿带交汇斜接部位,以同时发育钨多金属矿床和银金铅锌锰矿床组合为特色,是南岭地区最重要的贵金属找矿远景区之一。近年来,在成矿系列理论指导下,银坑矿田在破碎带热液脉型贵金属找矿方面取得重要突破,在陆内成矿理论创新方面取得了重要进展。本文系统总结了银坑矿田两类矿床的时空分布规律、成矿期次与控矿要素,结合南岭科学钻探两类矿化的垂向分带特征,阐明了两类矿化组合在三维空间内的分带性,在成矿时间上的集中性(150~160 Ma),是华南中生代两类矿床成矿系列(南岭与花岗岩有关钨锡矿床成矿系列和赣东北与花岗闪长岩有关贵金属成矿系列)在银坑地区时空四维尺度的叠加。按成矿系列之"全位成矿与缺位找矿"理论,进一步指明了银坑地区的找矿方向,即应围绕江背复式岩体在内带寻找张家地式、在接触带寻找岩前式和狮吼山式、在外带寻找画眉坳式钨多金属矿床;在银坑—青塘盆地内围绕推覆构造上下盘开展贵金属找矿,重点部署推覆构造界面内和脉体收敛方向深部的厚大矿体勘查,在高山角和井笔山外围探索斑岩型-爆破角砾岩型矿化规模。 相似文献
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陕西省太白县双王金矿床属大型低品位角砾岩型金矿，矿床东段的矿体赋存层位是古道岭组，矿体产于角砾岩带中，含金角砾岩带的形成与断裂构造有关，其热液活动可划分5个阶段，Ⅱ1，Ⅲ2亚阶段为主要成矿阶段。矿体矿化规律、矿体特征、矿体成因具有独特性。文章对未探明地段进行了成矿预测，提出找矿靶区，并在部分地段已经得到验证。 相似文献
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S. Viswanathan K. Surya Prakash Rao B. Mahabaleswar 《Journal of the Geological Society of India》2013,82(6):621-627
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
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奥地利安东帕有限公司 《岩矿测试》2009,28(3):306-306
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
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E. M. Prasolov S. A. Sergeev B. V. Belyatsky E. S. Bogomolov K. A. Gruzdov I. N. Kapitonov R. Sh. Krymsky V. O. Khalenev 《Geochemistry International》2018,56(1):46-64
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
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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
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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
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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
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《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