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安徽省霍山县东溪-南关岭金矿地质特征与成矿条件 总被引:2,自引:0,他引:2
东溪-南关岭金矿为北淮阳东段发现的第一个原生金矿,产于磨子潭-晓天中生代火山盆地边缘,容矿围岩为安山质-英安质火山岩,矿化和蚀变受桐柏-桐城深大断裂带的次级构造带控制。该金矿发育陡倾斜的脉状矿体和缓倾斜的似层状矿体,成因类型为冰长石-绢云母型浅成低温热液金矿。火山岩盆地之下的变质基底可能起到了初始矿源层作用,桐柏-桐城断裂带及其次级构造破碎带为重要的导岩导矿构造,早白垩世强烈的岩浆活动提供了热源、动力源和部分矿源。参照国内外类似金矿的特征,认为本区成矿地质条件良好,有可能隐伏着与石英正长岩体有关的细脉浸染型矿化,晓天火山盆地具有良好的找矿前景。 相似文献
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胶东玲珑-焦家式金矿床矿源岩系(序)列研究 总被引:1,自引:0,他引:1
在前人研究成果的基础上 ,通过详细分析胶东岩体形成的环境、岩石地球化学成分、同位素、稀土特征以及它们与金矿的关系 ,逐步形成了对金矿床矿源岩系 (序 )列的初步认识 ,将胶东成矿矿源岩系划分为初始矿源岩、中间矿源岩系和直接矿源岩组合 ,并指出其主要找矿意义 相似文献
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五凤—五星山金矿床属中生代陆相火山岩低流型浅成热液型金矿床。侏罗系上统金沟岭组火山岩为其主要矿源层,矿体受火山机构的断裂、裂隙和次火山岩脉内外接触带控制。碱长花岗岩侵入金沟岭组底部,为金矿形成提供了热源。成矿作用主要在低压、中性介质和弱氧化、超浅成条件下进行。金矿一般富集于矿体上部;矿体转弯、膨大处及分支复合处;强冰长石绢云母硅化蚀变岩中;含细粒黄铁矿的方解石石英脉;辉银矿集中地段。 相似文献
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东北寨微细浸染到金矿床的成因,目前有二种说法:一说是矿源层供矿─减压沸腾─非岩浆水(主要为大气降水)热液对流循环成矿;另一说是构造动力作用于岩层和矿源层,引起岩层析水、升温增压,激发元素活化.驱动矿液运移,影响矿质沉淀聚集,在构造的一定部位定位。作者对矿床地质特征、矿床元素地球化学、同位素、稀土元素地球化学、包体测温及成分分析、构造模拟和高温高压实验资料等研究认为,其成因当属后者而非前者。并据矿体分布规律进行成矿预测,提高了钻探命中率,加速了勘探进程,取得了极好的成效,也验证了成矿理论的正确性。 相似文献
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湘西南是湖南重要的产金区,该区金矿以脉型金矿为主。按其成矿元素组合,该区脉型金矿可划分为单金石英脉型和金-锑石英脉型;按其矿体产出形态特征,可划分为顺层式和切层式脉型金矿两种。该区脉型金矿受地层、岩性和构造控制明显,矿物组合简单,金主要以自然金形式产出。该区脉型金矿形成主要与脆、韧性剪切作用有关,雪峰山一带加里东期的剪切作用,使该区的浅变质岩发生变形,并促使地层中的成矿物质发生活化、迁移,最终富集形成金矿床,因此,该区金矿的成因类型为与剪切带有关的中低温热液金矿床。 相似文献
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金山金矿田岩石遭受了三期不同性质的构造变形,这三期构造变形对金矿体的形成起着决定作用。其中第二期早期韧性剪切变形阶段形成了矿田主要的控矿、容矿构造(金山-西蒋韧性剪切带),晚期脆性剪切变形阶段金矿体在动性剪切带中定位。本文通过高温三轴应力实验,对不同岩性的岩石在相同实验条件下的构近变形机制.和同种岩性的岩石在不同实验条件下的构造变形机制进行了模拟,为金山金矿田成矿提供了实验资料和依据。 相似文献
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Paul Ney 《Die Naturwissenschaften》1981,68(12):597-605
Types of asbestos are distinguished not only by structure, chemical compositon, shape of aggregates, and length and quality of fibers, but also by its formation. Though consisting of quite common elements, deposits are formed only under very special conditions. Its unique combination of properties has created over 3000 fields of application (about 70% in asbestos cement). Great efforts have been made to substitute all types of asbestos by harmless, similarly cheap and versatile synthetic fibers, owing to the unquestioned carcinogenic properties of all asbestos dusts. However, development of such fibers has not made any remarkable progress until recently. Consequently risk to workers in mining and manufactoring, consumers, outsiders, and the environment should be kept as low as possible by intensifying precautions and diminishing emissions. 相似文献
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This work was conducted to evaluate whether Ca-bearing additives used during coal combustion can also help with the retention of some other elements. This work was focused on the evaluation of bottom ashes collected during four full-scale combustion tests at an operating thermal fluidized-bed power station. Bottom ashes were preferred to fly ashes for the study to avoid interference from condensation processes usually occurring in the post-combustion zone. This work focused on the behaviors of S, Cl, Br, As, Mn, V, Cr, Ni, Cu,Zn, W, and Pb. Strong positive correlations with CaO content in bottom ashes were observed(for all four combustion tests) for S, As, Cl and Br(R = 0.917-0.999). Strong inverse proportionality was calculated between the contents of Pb, Zn, Ni, Cr and Mn and CaO, so these elements showed association to materials other than Ca-bearing compounds(e.g., to aluminosilicates, organic matter, etc.). Somewhat unclear behaviors were observed for W, Cu, and V. Their correlation coefficients were evaluated as statistically "not significant", i.e., these elements were not thought to be significantly associated with CaO. It was also discovered that major enrichment of CaO in the finest bottom ash fractions could be advantageously used for simple separation of elements strongly associated with these fractions, mainly S and As, but also Cl or Br. Removal of5% of the finest ash particles brings about a decrease in As concentration down to 77%-80% of its original bulk ash content, which can be conveniently used e.g., when high As content complicates further ash utilization. 相似文献
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珊瑚钨锡矿硅质尾矿中Cd、As、Zn、F富集迁移及环境污染 总被引:1,自引:0,他引:1
硅质尾矿在释放中性矿山废水(NMD)时所伴生的多元素复合污染问题值得重视。本文以桂东北珊瑚矿尾矿作为研究对象,通过分析该尾矿的组构、元素富集及迁移特性,筛选出主要污染元素,并探讨尾矿胶结层对元素富集迁移的影响。结果表明:(1)该尾矿中Cd、As、Zn及F富集程度较高、可交换态含量(易迁移释放量)较大,是主要的污染元素,而Cu、Pb、Tl产生污染的可能性较小;(2)胶结层对重金属具有再富集作用,但其对可交换态Cd、As(Tl)再富集明显,而对可交换态Cu、Pb、Zn再富集则不明显。胶结层中次生伊利石、石膏等胶结物趋向于吸附富集活性可交换态Cd、As。这表明该尾矿可能迁移释放出含Cd、As浓度较高的NMD。研究表明,硅质尾矿风化释出NMD的同时,可能伴生Cd、As、Zn等重金属以及F的复合污染。 相似文献
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Kurunthachalam Kannan Simonetta Corsoline Takashi Imagaws Silvano Focardi John P.Giesy 《Ambio-人类环境杂志》2002,31(3):207-211
我们曾对从意大利收集的金枪鱼、箭鱼、普通鸬鹚以及家燕体内的p,p'-DDE、多氯联苯同类物(PCBs)、多氯二苯-p-二恶英(PCDDs)、多氯二苯并呋喃(PCDFs)以及多氯萘(PCNs)浓度进行过测量. 相似文献
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Vine Edward L. Sathaye Jayant A. 《Mitigation and Adaptation Strategies for Global Change》2000,5(2):189-216
In this paper, we present an overview of guidelinesdeveloped for the monitoring, evaluation, reporting,verification, and certification (MERVC) ofenergy-efficiency projects for climate changemitigation. The monitoring and evaluation ofenergy-efficiency projects is needed to determine moreaccurately their impact on greenhouse gas (GHG)emissions and other attributes, and to ensure that theglobal climate is protected and that countryobligations are met. Reporting, verification andcertification will be needed for addressing therequirements of the Kyoto Protocol. While the cost ofmonitoring and evaluation of energy-efficiencyprojects is expected to be about 5–10% of a project'sbudget, the actual cost of monitoring and evaluationwill vary depending on many factors, including thelevel of precision required for measuring energy andGHG reductions, type of project, and amount of fundingavailable. 相似文献
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《Journal of Cleaner Production》2006,14(17):1557-1558
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