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51.
样品经HF-HNO3-HClO4分解,在2mol/LHNO3介质中,采用感耦等离子体光电直读光谱法对铀矿石尾标准物质中的As、Ba、Be、Cd、Cr、Ni、Pb等和Sn进行定值分析。同一样品平行测定6次,其各元素的相对标准偏差在2%-10%。分析结果均落在标准值的置信区间。 相似文献
52.
衡山南岳岩体北侧,地质构造复杂,岩浆活动频繁,金矿成矿地质条件有利,已发现一个具有远景的金矿带,其中石子坳矿区为构造蚀变岩型金矿。本文简要地介绍了区域和矿区地质特征,总结出花岗闪长斑岩,硅化带和As元素化探异常等3条找矿标志,建议在该区开展大比例尺化探测量和地质填图,普查北西向硅化断裂破碎带,并对石子坳含金破碎带进行深部验证,寻找隐伏金矿床。 相似文献
53.
微生物地球化学探矿—蜡样芽孢杆菌法寻找金,铀矿的试验研究 总被引:4,自引:0,他引:4
壤中蜡样芽孢杆菌找矿法是微生物地球化学探矿方法之一。本文叙述了蜡样芽孢杆菌法的找矿原理、野外工作方法、室内测量技术、野外初步试验的地质效果以及测量中应注意的若干问题。在已知隐伏金矿床(点)和铀矿床(点)上测得了明显的蜡样芽孢杆菌计数异常,并在460铀(钼)矿床外围的铀矿化远景地段进行了试验,地质效果较为理想。 相似文献
54.
岷礼东部-湘潭子一带蕴藏着甘肃省最大的金矿床和铅锌矿庆。主要控矿地层为中泥盆统,该套地层地球化学条件优越,断裂构造十分发育,岩浆活动非常强烈,是金及多金属矿床的有利成矿地段。区内矿床可划分为四大系列,6个类型。利用地球化学特征,分析主要控矿因素对成矿的控制作用;总结主要矿种的成矿规律;筛选出3个找矿远景区。 相似文献
55.
Gold ore-forming fluids of the Tanami region, Northern Australia 总被引:1,自引:0,他引:1
Fluid inclusion studies have been carried out on major gold deposits and prospects in the Tanami region to determine the compositions
of the associated fluids and the processes responsible for gold mineralization. Pre-ore, milky quartz veins contain only two-phase
aqueous inclusions with salinities ≤19 wt% NaCl eq. and homogenization temperatures that range from 110 to 410°C. In contrast,
the ore-bearing veins typically contain low to moderate salinity (<14 wt% NaCl eq.), H2O + CO2 ± CH4 ± N2-bearing fluids. The CO2-bearing inclusions coexist with two-phase aqueous inclusions that exhibit a wider range of salinities (≤21 wt% NaCl eq.).
Post-ore quartz and carbonate veins contain mainly two-phase aqueous inclusions, with a last generation of aqueous inclusions
being very CaCl2-rich. Salinities range from 7 to 33 wt% NaCl eq. and homogenization temperatures vary from 62 to 312°C. Gold deposits in
the Tanami region are hosted by carbonaceous or iron-rich sedimentary rocks and/or mafic rocks. They formed over a range of
depths at temperatures from 200 to 430°C. The Groundrush deposit formed at the greatest temperatures and depths (260–430°C
and ≤11 km), whereas deposits in the Tanami goldfield formed at the lowest temperatures (≥200°C) and at the shallowest depths
(1.5–5.6 km). There is also evidence in the Tanami goldfield for late-stage isothermal mixing with higher salinity (≤21 wt%
NaCl eq.) fluids at temperatures between 100 and 200°C. Other deposits (e.g., The Granites, Callie, and Coyote) formed at
intermediate depths and at temperatures ranging from 240 to 360°C. All ore fluids contained CO2 ± N2 ± CH4, with the more deeply formed deposits being enriched in CH4 and higher level deposits being enriched in CO2. Fluids from deposits hosted mainly by sedimentary rocks generally contained appreciable quantities of N2. The one exception is the Tanami goldfield, where the quartz veins were dominated by aqueous inclusions with rare CO2-bearing inclusions. Calculated δ
18O values for the ore fluids range from 3.8 to 8.5‰ and the corresponding δD values range from −89 to −37‰. Measured δ
13C values from CO2 extracted from fluid inclusions ranged from −5.1 to −8.4‰. These data indicate a magmatic or mixed magmatic/metamorphic source
for the ore fluids in the Tanami region. Interpretation of the fluid inclusion, alteration, and structural data suggests that
mineralization may have occurred via a number of processes. Gold occurs in veins associated with brittle fracturing and other
dilational structures, but in the larger deposits, there is also an association with iron-rich rocks or carbonaceous sediments,
suggesting that both structural and chemical controls are important. The major mineralization process appears to be boiling/effervescence
of a gas-rich fluid, which leads to partitioning of H2S into the vapor phase resulting in gold precipitation. However, some deposits also show evidence of desulfidation by fluid–rock
interaction and/or reduction of the ore-fluid by fluid mixing. These latter processes are generally more prevalent in the
higher crustal-level deposits. 相似文献
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58.
根据成矿作用、成矿环境及矿床特征,金沙江流域(云南段)砂金矿床,可划分为:残坡积、洪积、冲洪积、冲积和冰碛等五种类型。成矿主要受碰撞带、深大断裂、大断裂及其派生断裂、基底岩石、地貌、水质和水化学环境等综合控制。以巨甸-大具及中江街-金江街两片区最具有找矿前景。 相似文献
59.
缅北中部,印缅岛弧及弧后盆地东侧、新生代造山带的前缘推覆构造带中,分布有许多脉金矿床及矿点,构成金矿带。矿带、矿田、矿床及矿体的形成、分布及其规模,受不同级别的近南北向逆冲断裂,及其间派生的北东向张性扩容断裂组成的剪切断裂带控制。可渗透的下麦尔组下部中一粗粒砂岩,起着很好的容矿作用。下麦尔组上部泥岩、细砂岩、粉砂岩和页岩互层单元,在携金热液的迁移、氧化硅的沉淀和矿质沉积定位等方面,可能起到圈闭作用。 相似文献
60.
West Sarawak,which located in the northwest of South Kalimantan Diwa Region,underwent geosynclinal period (An C-T),platform period (J1-J2) and diwa period (J3-).In geosynclinal evolution period,the crust was thickened and accreted by sedimentary accumulating,orogenic movement and metamorphism.In the different kinds of volcanic-sedimentary rocks,content of gold is general higher than the mean value of upper crust and its enrichment factor ranges from 0.94 to 4.7.The basement tectonics formed in geosynclinal fold inversionstage strike northeast,which controlled the distribution ofmagmatic activities and gold mineralization belts of the west part of west Sarawak. 相似文献