国际矿产品价格影响因素研究

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。     

大数据视角下的地矿工作发展与变革研究

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。     

日照市东南部地区榴辉岩矿矿石加工技术性能及选矿工艺研究

日照市东南部岚山安东卫、虎山地区位于苏鲁榴辉岩带南西段的中部,区域内赋存大型榴辉岩矿体,榴辉岩资源较丰富。榴辉岩含有的石榴子石、绿辉石、金红石都是应用很广的矿物,但榴辉岩的选矿工艺比较复杂,特别是其中金红石的选矿分离一直难以解决。该文就日照东南部地区的榴辉岩矿石的加工技术性能及选矿工艺进行了试验和探讨研究,为今后该区榴辉岩矿的开发利用打下了一定基础。     

Developing the tools for geological shape analysis,with regional‐ to local‐scale examples from the Kalgoorlie Terrane of Western Australia

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.     

Petrology and geothermobarometry of granulite facies metapelites from the Hisøy-Torungen area, south Norway: new data on the Sveconorvegian P–T–t path of the Bamble sector

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.     

扬子地台北缘晚震旦世微古植物特征及意义

本文着重研究了扬子地台北缘上震旦统陡山沱组、灯影组及下寒武统下部岩家河段的微古植物组合特征。初步建立了Ⅰ、Ⅱ两个微古植物组合，分别与陡山沱村阶和灯影峡阶相对应，分析了微古植物组合在地层划分与对比及在震旦系－寒武系界线的划分上所起的作用。     

辽宁省大石桥－吉洞峪一带辽河岩群变质地层的对比研究

辽宁省大石桥－吉洞峪一带出露的主要为古元古代的变质层状岩系，由云母片岩、长英质粒岩和大理类组成。区域上形成一大型北东向的复式向斜构造。复向斜南北两翼变质地层对比问题是辽吉东部辽河岩群研究的主要内容之一。作者根据五年来在大石桥－吉洞峪一带进行１∶５万区调所获得的新资料，从标志层及组合标志层、岩相学特征、主要标志层的岩石化学和稀土地球化学特征、变质作用演化等方面的研究入手，讨论了复向斜两翼变质地层对比的问题。结果表明，辽河岩群构成复向斜南北两翼的变质地层是完全可以对比的，从而进一步证实辽河岩群是一个不可分割的整体     

桂北江南古陆南缘拗褶带中铅锌矿产成矿信息特征及预测标志

本文通过研究与总结前人成果基础上.对桂北江南古陆南缘拗褶带中铅锌矿进行成矿预测。文中侧重探讨了该带的成矿环境、典型矿床特征、控矿因素和地球物理、地球化学特征;综合地、物、化成矿信息.总结提出了7 条成矿预测标志:采用特征分析法对该带中的19个成矿单元进行资源定性预测评价,认为其铅锌矿资源潜力较大,有找矿前景。     

大坂山含“铬矿物”石英闪长岩岩石特征

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。     

矿山废石淋溶对水环境的影响

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。