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411.
国际矿产品价格影响因素研究 总被引:1,自引:0,他引:1
矿产品具有的供需空间分离、基础性和战略性、不可再生性及金融属性等一系列基本属性和特点。本文结合商品价值价格理论和矿产品的特性,通过一系列鲜活的矿产品价格变化案例,研究了影响世界主要大宗矿产品价格涨跌的因素,归纳总结出了影响世界矿产品价格变化的4类因素:矿产品供给、矿产品需求、突发性事件和国际金融市场。 相似文献
412.
大数据视角下的地矿工作发展与变革研究 总被引:1,自引:0,他引:1
本文提出了地矿大数据应用需要考虑地球系统和社会系统两个方面的内部规律,分析了地矿大数据的三类组成,给出了地矿大数据的四层应用架构;重点就大数据下地矿工作发展和变革提出了四项建议,包括重视数据,转变地矿工作决策模式;收集数据,夯实地矿工作决策基础;分析数据,提高地矿工作科学决策水平;开放数据,提高地矿工作服务能力和水平。 相似文献
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414.
S. J. Gardoll D. I. Groves C. M. Knox-Robinson G. Y. Yun N. Elliott 《Australian Journal of Earth Sciences》2013,60(5):943-953
Geological map data are often underused in mineral‐exploration programs, which rely increasingly on regolith geochemistry and geophysical and other remotely sensed data to generate exploration targets. However, solid geology maps, which are progressively being upgraded due to improved interpretations of superior, remotely sensed images and airborne geophysical data, can be useful in targeting specific types of mineral deposits, which formed late in the evolutionary history of the host terrane. In such terranes, the present map geometry is essentially the same as that at the time of deposit formation. This is the case for orogenic lode‐gold deposits, which commonly show predictable structural controls and/or structural geometry. Thus, the shape of a rock body, or combinations of structures and rock bodies, may provide an important guide to the exploration potential for orogenic lode‐gold deposits. However, until recently, there has been a dearth of techniques to quantify the various properties of shape, and hence test the potential of the two‐dimensional shape of geological bodies in map view as an exploration tool. Integrating techniques from the field of pattern recognition with a modern Geographical Information System (GIS) can provide the shape‐analysis tools required to investigate the geometries of geological shapes. Two‐dimensional shape analysis is now possible through the calculation of several shape metrics including, but not restricted to, aspect ratio, blockiness, elongation, compactness, complexity, roundness, spreadness and squareness. Methods are developed for describing the geometries of rock units about mineral deposits, or any geological features, at any scale, which for the first time makes it possible to compare shapes. These shape‐analysis techniques are tested using orogenic lode‐gold deposits, particularly those in the Kalgoorlie Terrane of the highly auriferous Late Archaean Norseman‐Wiluna Belt of Western Australia. On a global scale, shape analysis indicates that those greenstone belts whose volcanic rock sequences have high elongation and relative low roundness, complexity and aspect ratio (e.g. Kalgoorlie Terrane) are likely to be the most richly endowed in gold. On a more local scale, characteristics of the shape of geological features around the Golden Mile deposit are calculated and used to test the likelihood of occurrence of gold deposits with similar geometry elsewhere in the Kalgoorlie Terrane. The area with the most closely matching shape, on the basis of a 2 km clipping‐circle radius, chosen on the basis of available proximity‐analysis data, corresponds to the recently discovered Ghost Crab deposit, illustrating the potential of the shape analysis methodology in mineral exploration. Shape analysis is, at least in part, scale dependent, due to the inherent problem of being able to define rock boundaries more precisely in units that have strong geophysical signatures than those with weak signatures in poorly exposed terranes. Overcoming this problem is a challenge to the application of this methodology. 相似文献
415.
T.-L. KNUDSEN 《Journal of Metamorphic Geology》1996,14(3):267-287
ABSTRACT The high-grade rocks (metapelite, quartzite, metagabbro) of the Hisøy-Torungen area represent the south-westernmost exposures of granulites in the Proterozoic Bamble sector, south Norway. The area is isoclinally folded and a metamorphic P–T–t path through four successive stages (M1-M4) is recognized. Petrological evidence for a prograde metamorphic event (M1) is obtained from relict staurolite + chlorite + albite, staurolite + hercynite + ilmenite, cordierite + sillimanite, fine-grained felsic material + quartz and hercynite + biotite ± sillimanite within metapelitic garnet. The phase relations are consistent with a pressure of 3.6 ± 0.5 kbar and temperatures up to 750–850°C. M1 is connected to the thermal effect of the gabbroic intrusions prior to the main (M2) Sveconorwegian granulite facies metamorphism. The main M2 granulite facies mineral assemblages (quartz+ plagioclase + K-feldspar + garnet + biotite ± sillimanite) are best preserved in the several-metre-wide Al-rich metapelites, which represent conditions of 5.9–9.1 kbar and 790–884°C. These P–T conditions are consistent with a temperature increase of 80–100°C relative to the adjacent amphibolite facies terranes. No accompanying pressure variations are recorded. Up to 1-mm-wide fine-grained felsic veinlets appear in several units and represent remnants of a former melt formed by the reaction: Bt + Sil + Qtz→Grt + lq. This dehydration reaction, together with the absence of large-scale migmatites in the area, suggests a very reduced water activity in the rocks and XH2O = 0.25 in the C–O–H fluid system was calculated for a metapelitic unit. A low but variable water activity can best explain the presence or absence of fine-grained felsic material representing a former melt in the different granulitic metapelites. The strongly peraluminous composition of the felsic veinlets is due to the reaction: Grt +former melt ± Sil→Crd + Bt ± Qtz + H2O, which has given poorly crystalline cordierite aggregates intergrown with well-crystalline biotite. The cordierite- and biotite-producing reaction constrains a steep first-stage retrograde (relative to M2) uplift path. Decimetre- to metre-wide, strongly banded metapelites (quartz + plagioclase + biotite + garnet ± sillimanite) inter-layered with quartzites are retrograded to (M3) amphibolite facies assemblages. A P–T estimate of 1.7–5.6 kbar, 516–581°C is obtained from geothermobarometry based on rim-rim analyses of garnet–biotite–plagioclase–sillimanite–quartz assemblages, and can be related to the isoclinal folding of the rocks. M4 greenschist facies conditions are most extensively developed in millimetre-wide chlorite-rich, calcite-bearing veins cutting the foliation. 相似文献
416.
417.
大坂山“铬矿物”产出于灰绿色中细粒石英闪长岩中,笔者从区域地质特征、岩石学、岩石化学、地球化学、同位素等方面对石英闪长岩进行了较全面的研究后认为,该套岩石成因为壳幔混合型,构造环境为北祁连加里东洋盆收缩阶段板块俯冲作用下形成的火山弧,岩石成岩时代为早奥陶世,铬矿物形成深度约30km,受区域性岩石圈断裂带控制。 相似文献
418.
矿山废石淋溶对水环境的影响 总被引:3,自引:1,他引:2
为了研究废石堆砌对水环境的影响,通过对废石做淋溶实验,分析了出入水的水质变化规律,对废石衍生环境效应的过程、机制、影响因素方面进行讨论,揭示了人们容易忽视的酸性水中硫酸根、总硬度、微量金属离子的动力学变化机理,指出矿山废石对水环境的污染不至限于使水质酸化,硫酸根、总硬度也会大幅度提高,废石堆放应充分考虑当地的地理气候及水文条件,合理堆放,减少污染。 相似文献
419.
饮用矿泉水作为一种新型饮料已被广大群众所接受,但真正进入国内、国际市场的数量与其丰富的资源形势不相匹配。原因是我国目前评价指标与国际通用指标尚不接轨。本文对其中一些问题提出质疑,试图修正现行评价指标和改善管理制度,以推动我国饮用矿泉水的进一步开发。 相似文献
420.
成矿定量预测与深部找矿 总被引:19,自引:1,他引:18
成矿预测是在不确定条件下制定最优决策的工作。成矿预测作为一种地质系统,与其他技术、经济系统存在重要区别。由于矿床类型的多样性,矿床成因的复杂性,控矿因素的隐蔽性和找矿信息的多解性,成矿预测结果具有不确定性并常常因人而异。探索成矿预测过程客观化、定量化和精确化一直是成矿预测学的前沿课题。文中以个旧锡矿为例展示致矿地质异常与矿体空间产出及分布的密切关系,强调以"求异"准则为指导的成矿定量预测的重要性。当今地质勘查工作面临深部找矿问题,论文从深部找矿的概念、类型、目标、效益等方面简要介绍了国外理论研究和找矿实践概况。强调深部找矿中要加强地壳深部结构的研究,要重视深部找矿的经济"回报率"和勘查项目的"转化率"的重要性。 相似文献