哀牢山金矿带原生金矿床矿物标型特征及找矿矿物学标志

本文讨论了哀牢山金矿带原生金矿床矿物组合特征、金矿物及载金矿物的形态、化学成分、晶体结构、物理性质、包裹体成分方面的找矿标型特征和找矿矿物学标志。     

某金矿五种单矿物中金的分析方法研究

对某金矿中的苋铁矿,毒砂,石英,云母和辉锑矿五种单矿物分别进行了金的分离,富集和分析方法研究,选择,不同试剂分解单矿物,用活性炭吸附,分离,原子吸收光谱法测定金,分析结果与其它研究结果相符。     

湘西地区铂族矿物的发现及其找矿意义

在湘西地区勘查金刚石矿的自然重砂和人工重砂样中,发现了较多的铂族矿物,且铂族矿物与金刚石及砂金紧密共生。湘西地区共发现铂族矿物出土点7个,为寻找潜在矿产资源提供了新信息。     

金矿找矿矿物学的几个问题

提出了金的指示矿物找矿矿物学分类方案,即按指示矿物出现的频率与分布广度;按指示矿物与金矿体的空间关系;按同一种矿物在同一工作区内的找矿意义进行分类。     

主要载金矿物及其找矿意义

本文重点研究了除黄铁矿（另文介绍）以外的石英、方铅矿、黄铜矿、闪锌矿、菱铁矿、褐铁矿等载金矿物的矿物学特征及其找矿意义。研究结果表明，石英的颜色和其中的Ｐｂ、Ｃｕ含量，方铅矿中的Ａｇ、黄铜矿的晶胞参数等具有找金和评价的标型意义。石英的红外光谱和包体研究可以揭示其形成温度和后期变形情况，方铅矿的空间分布极不均匀，可能与金矿形成时代有关。另外，本文纠正了前人把菱铁矿误认成铁白云石的作法。     

Mineral Paragenesis of the Lepanto Copper and Gold and the Victoria Gold Deposits, Mankayan Mineral District, Philippines

Abstract: Mineral paragenesis of the alteration, ore and gangue minerals of the Lepanto epithermal copper‐gold deposit and the Victoria gold deposit, Mankayan Mineral District, Northern Luzon, Philippines, is discussed. The principal ore minerals of the Lepanto copper‐gold deposit are enargite and luzonite, with significant presence of tennantite‐tetrahedrite, chalcopyrite, sphalerite, galena, native gold/electrum and gold‐silver tellurides. Pervasive alteration zonations are commonly observed from silicification outward to advanced argillic then to propylitic zone. The ore mineralogy of the Lepanto copper‐gold deposit suggests high f_S2 in the early stages of mineralization corresponding to the deposition of the enargite‐luzonite‐pyrite assemblage. Subsequent decrease in the f_S2 formed the chalcopyrite‐tennantite‐pyrite assemblage. An increase in the f_S2 of the fluids with the formation of the covellite‐digenite‐telluride assemblage caused the deposition of native gold/electrum and gold‐silver tellurides. The principal ore minerals of the Victoria gold deposit are sphalerite, galena, chalcopyrite, tetrahedrite and native gold/electrum. The alteration halos are relatively narrow and in an outward sequence from the ore, silica alteration grades to illitic‐argillic alteration, which in turn grades to propylitic alteration. The Victoria gold mineralization has undergone early stages of silica supersaturation leading to quartz deposition. Vigorous boiling increased the pH of the fluids that led to the deposition of sulfides and carbonates. The consequent decrease in H₂S precipitated the gold. Gypsum and anhydrite mainly occur as overprints that cut the carbonate‐silica stages. The crosscutting and overprinting relationships of the Victoria quartz‐gold‐base metal veins on the Lepanto copper‐gold veins manifest the late introduction of near neutral pH hydrothermal fluids.     

Victoria Carbonate-Base Metal Gold Deposit and Its Significance in the Mankayan Mineral District, Luzon, Philippines

Abstract. The Victoria gold deposit is a low-sulfidation style epithermal carbonate-base metal gold deposit discovered in 1995 in the Mankayan mineral district, northern Luzon, Philippines. It occurs just south of a high-sulfidation copper-gold orebody (Lepanto enargite deposit) and a porphyry copper-gold orebody (Far Southeast (FSE) deposit). Radiometric dating of the Victoria mineralization yields ages from 1.6 to 1.1 Ma, similar to ages of the Lepanto enargite deposit. Mineralogical, geochemical, fluid inclusion and sulfur isotope studies suggest that the Victoria deposit is not directly related to the late stage of hydrothermal activity that produced the FSE porphyry copper-gold and the Lepanto enargite deposits. The hydrothermal fluids from which Victoria was formed appear to have been derived from the south, and not from the FSE intrusive center to the northeast. This would suggest a regional south to north hydrothermal gradient, consistent with the similar flow within the FSE porphyry-Lepanto enargite system. On a district scale, structures similar to those of the Victoria deposit in trend and nature would be highly prospective, especially if they occur north of identified plutons and volcanic centers.     

Carlin-type Gold Prospects in Surigao del Norte, Mindanao Island, Philippines: Their Geology and Mineralization Potential

Abstract. Three calcareous sedimentary rock-hosted Carlin type-like gold prospects were mapped in a mineral production sharing agreement area of Philex Gold Philippines Inc. in Taganaan municipality, Surigao del Norte province in Mindanao island in the Philippines. They occur along a 20–25 km long trend of known epigenetic gold and porphyry copper deposits that lie close to several splays of the Philippine Fault Zone. The gold district forms part of the Late Cretaceous Eastern Mindanao Range that hosts early Paleogene and late Pliocene to Quaternary intrusive rocks.
Gold is invisible in the jasperoid outcrops in Lascogon, Napo, and Danao prospects. The jasperoids occur in lenses of marls belonging to the Taganaan Marl Member that is associated to a turbiditic member of the Middle Miocene Mabuhay Formation. The marl lenses include gently dipping interbedded silty limestones and calcareous shales. The "invisible gold" mineralization in silicified calcareous rocks resembles Carlin-type deposits. Based on the mapped igneous and sedimentary rocks, a possible heat source for the gold mineralization is either or both of the two main phases of intrusion, Mabuhay An-desite or Alipao Andesite Porphyry. Forty-eight rock samples, fifteen stream sediment samples, and one soil sample were critical in delineating the general features of the potential Carlin-type prospects. The gold grades of jasperoids in the three prospects range from trace amounts to 20 g/t Au. Regional studies of gold and porphyry copper mineralization in the Surigao del Norte mineral district are important in delineating ore targets for drilling in the three prospects.     

胶东西北部地区现代河流砂金的聚集规律及水动力学解释

研究区位于胶东半岛西北部，具有丰富的岩金和砂金资源，是我国目前重要的黄金产地。作者应用沉积学和水动学的理论和方法，重点研究了该地区现代河流的沉积学特征、砂金聚集规律及其形成的水动力条件，认为河流砂金的聚集是一个与机械成矿作用密切相关的动态过程，与特定的河流水动力条件有关，其中横向环境的底流对于形成河谷台阶状缓坡倾斜面及砂金聚集具有重要意义。     

珲春河流域砂金中微量铅同位素组成及其来源

砂金中的微量铅同位素分析具有特殊的意义.可根据Pb同位素的μ、υ、ω等值确定砂金的来源及可能的原生金矿体,本文测试了珲春河流域中的砂金及附近岩石和矿物Pb同位素,为寻找原始金矿和岩体提供了极其重要的同位素地质依据.砂金中铅的化学分离是采用阴阳离子交换技术,以甲醇作为载体进行砂金中微量铅的富集、分离纯化,使铅与金彻底分离,以达到高精度和准确的铅同位素测定.     

中国东北寒区的风化壳与砂金矿床

大、小兴安岭北部寒区发育有3个砂金富集区.大量的找矿实践表明, 区内砂金矿床与内生成矿作用没有必然的联系, 砂金矿床与区域发育的风化壳有着密切的空间关系, 风化壳中的低温地球化学作用对区域砂金矿床的形成具有一定的控制作用.在砂金的形成过程中寒冻气候条件至关重要, 寒冷的气候条件有利于风化壳的保存, 同时, 冰冻条件下的水文地质条件及电化学作用也有利于金在其中的活化、迁移、富集和生长.     

金平断块及其矿产

金平断块是哀牢山成矿域东南地区最有利的成矿带，成矿与断裂带关系密切，矿带的展布亦严格受构造控制。金平断块可划分为四个元素异常集中区，集中了金、银、铜、铜镍、铜钼、铅锌、铌钽、铂钯等金属矿产和元素异常。每一区有不同的元素组合及矿产。目前，金、铜镍、铜钼等已进行开发利用，铜、铂钯、铌钽、铅锌等已获找矿信息，矿床潜力巨大，矿业开发已成为地方经济发展的支柱产业。由于成矿理论研究及矿床综合评价滞后，极大阻碍该区矿业开发一体化的发展进程，这种局面必须扭转。     

江西黄沙金矿床黄铁矿矿物学特征研究

通过对江西黄沙金矿床中黄铁矿的产状及形态特征、成分特征、晶胞参数特征、热电性、红外光谱特征等矿物学的详细研究 ,讨论了黄沙矿中蕴藏的金矿成因及找矿信息 ,为正确评价该矿床和在该区找寻新的金矿点 (带 )提供了重要的依据。