舒兰市福安堡钼矿床地质特征及找矿意义

本文较详细地介绍了福安堡中型斑岩钼矿床的地质特征、找矿标志及找矿方法,对在吉林地区北部舒兰—蛟河一带分布的印支—燕山期花岗岩区寻找大、中型斑岩型钼矿床具有重要的指导意义。     

云南绿春咪霞金矿成矿地质条件

咪霞金矿赋存在多元素高背景值下志留统薄层状蚀变板岩中,受北西向F6-1断裂及正长岩、煌斑岩控制,与多元素异常、黄铁矿化等多种围岩蚀变对应,具较好的成矿地质条件。     

枞阳县拔茅山矿区拔茅山-余家园-李家湾-石庄环状成矿带地质特征及找矿潜力分析

由余家园、李家湾、石庄、拔茅山铜矿带环绕皂树咀辉石粗安玢岩体与上侏罗统砖桥组火山岩系地层内外接触带附近构成未封闭的环状矿带,具面状蚀变,铜草发育,矿化多呈细脉浸染状,地表矿化普遍较强,寻找与拔茅山铜矿类似近接触带细脉浸染型带状斑岩型铜矿具一定潜力.     

四川稻城竹鸡顶铜矿地质特征及成矿特点

竹鸡顶斑岩型铜矿位于西南三江成矿带内,热液蚀变以青磐岩化、泥化为特征。区内现已圈出1个矿带和2个矿化带,并有幅频激电异常、土壤铜异常与之套合。该区具有较好的找矿前景。     

内蒙古阿鲁科尔沁旗好力宝铜钼矿床地质特征及找矿方向

好力宝铜钼矿床属与燕山期隐伏的隐爆角砾状斜长花岗斑岩和碎裂次石英斑岩有关的热液脉状和斑岩型矿床.铜钼矿体受隐爆角砾岩筒和岩体控制,矿化产在蚀变隐爆角砾岩和硅化带中.今后的找矿方向应侧重于对斜长花岗斑岩与围岩接触带和碎裂次石英斑岩中化探异常和低阻高极化异常地段的探索.     

论南岭成矿带大宝山斑岩型铜矿的特殊性及其勘查意义

广东省大宝山矿床是南岭成矿带唯一的大型铜多金属矿床，此次研究在矿区中南部发现了细脉浸染状铜矿的新类型。为确定其是否为斑岩型铜矿的成因类型，本文在梳理南岭成矿带铜成矿条件和成矿规律的基础上，查明了矿区中南部英安斑岩的蚀变和铜矿化特征。综合研究认为南岭成矿带早侏罗世中酸性斑岩的小岩体较多，叠加多期断裂构造和碳酸盐岩建造，非常有利于铜多金属成矿物质的运移、富集。大宝山英安斑岩发育黑云母化、钾长石化、青磐岩化、绢英岩化、泥化等蚀变类型，铜矿化与绢英岩化、绿泥石化关系密切。大宝山铜矿中的英安斑岩沿逆冲推覆构造侵位并呈岩墙状产出，冷却过程中受区域构造应力产生了一组平行裂隙，岩浆房去气作用排出的热液沿裂隙蚀变围岩并充填成矿。大宝山斑岩型铜矿取得的找矿勘查成果表明，“全位成矿，缺位找矿”理念可以有效指导靶区圈定和老矿山外围（深部）找矿勘查，早侏罗世的南岭具有形成较大规模斑岩型铜矿的条件。     

Hydrogeochemical controls on surface and groundwater chemistry in naturally acidic, porphyry-related mineralized areas, southern Rocky Mountains

In southern Rocky Mountains, catchments characterized by acidic, metalliferous waters that are relatively unaffected by human activity usually occur within areas that have active or historical mining activity. The US Geological Survey has utilized these mineralized but unmined catchments to constrain geochemical processes that control the surface- and ground-water chemistry associated with near surface acid weathering as well as to estimate premining conditions. Study areas include the upper Animas River watershed, Lake City, Mt. Emmons, and Montezuma in Colorado and Questa in New Mexico. Although host-rock lithologies range from Precambrian gneisses to Cretaceous sedimentary units to Tertiary volcanic complexes, mineralization is Tertiary in age and associated with intermediate to felsic composition, porphyritic plutons. Pyrite is ubiquitous. Variability of metal concentrations in water is caused by two main factors： mineralogy and hydrology. Parameters that potentially affect water chemistry include： host-rock lithology, intensity of hydrothermal alteration, sulfide mineralogy and chemistry, gangue mineralogy, length of flow path, precipitation, evaporation, and redox conditions. Springs and headwater streams have pH values as low as 2.5, sulfate up to 3700 mg/L and high dissolved metal concentrations （for example： Al up to 170 mg/L; Fe up to 250 mg/L; Cu up to 3.5 mg/L and Zn up to 14 mg/L）. With the exception of evaporative waters, the lowest pH values and highest Fe and Al concentrations occur in water draining the most intense hydrothermally altered areas consisting of the mineral assemblage quartz-sericite-pyrite. Stream beds tend to be coated with iron floc, and some reaches are underlain by ferricrete. When iron-rich ground water interacts with oxygenated waters in the stream or hyporheic zone, ferrous iron is oxidized to ferric iron, which is less soluble, leading to the precipitation of iron oxyhydroxides.     

富碱斑岩中超镁铁深源包体岩石的矿物学特征

在云南省鹤庆县六合乡富碱斑岩体中找到超镁铁深源岩石包体，这对于研究富碱斑岩的起源和演化及其成岩成矿作用具有重要意义。本文较系统地研究了深源包体岩石的矿物学特征，揭示该深源包体具有原始上地幔岩在地幔条件下受到一定程度富集地幔流体交代作用改造的特征，具有富集地幔低程度部分熔融属性，为富碱斑岩的成岩成矿演化提供了重要的矿物学依据。     

四川盐源西范坪斑岩铜矿的钾长环斑结构及其意义

四川盐源西范坪斑岩铜矿床中存在大量钾长环斑结构。研究表明这一结构是由正在冷凝的岩浆分泌出的成矿流体与刚结晶的斜长石相互作用形成的。在流体－矿物相互作用过程中，流体从已经结晶的矿物尤其是黑云母中萃取出大量铜等成矿物质，从而进一步提高了体系的成矿能力。钾长环斑结构的出现不仅为矿床的岩浆热液成因提供了佐证，而且是一种良好的找矿标志。     

全球超大型斑岩铜矿床形成的构造背景分析

全球近四分之三的超大型斑岩铜矿形成于太平洋东岸,绝大部分斑岩铜矿形成于中新生代.斑岩铜矿常产于板块俯冲的上盘和陆内造山带.部分斑岩铜矿在形成时间上与板块俯冲作用存在一定的差异,全球绝大部分的斑岩铜矿的形成可能与张性环境有关.成矿斑岩起源于地幔,下地壳或洋壳物质的参与起到了重要作用.在重点对冈底斯和玉龙成矿带含矿斑岩的地球化学特征和构造背景分析的基础上,提出拆沉作用可能是斑岩铜矿形成的重要机制.