论东川脉状富铜矿的历史和现实意义   总被引：6，自引：1，他引：6  

薛步高  刘恩发 《矿产与地质》1997,11(4):217-224

东川脉状富铜矿在历史上对矿山、对国家曾作出过重大贡献。汤丹厚大的层状铜矿也是５０年代在广泛调查汤丹脉状矿的基础上发现的，从而肯定整个东川矿区层状矿的巨大工业价值。对脉状铜矿的成因，长期以来受着“脉状铜矿由层状铜矿就地取材”转化形成的思想束缚，因而对其评价－研究成果甚少。从脉矿现有的历史资料出发，结合当今的研究成果，认为东川矿区广泛分布含铜大于５％的富脉矿，脉矿与层状矿在伴生元素、稀土配分、硫同位素组成，爆裂测温等方面，二者均有明显的区别。脉铜矿是以深源为主形成的。建议对历史上曾开采，但至今未作详细地质工作的茂麓铜厂尽快予以评价。  相似文献   

Geochemical signature of orogenic hydrothermal activity in an active tectonic intersection zone,Alpine Fault,New Zealand   总被引：1，自引：0，他引：1  

J.?R.?Campbell  D.?CrawEmail author  R.?Frew  T.?Horton  C.?P.?Chamberlain 《Mineralium Deposita》2004,39(4):437-451

A highly faulted and fractured rock mass has developed at the intersection of the Alpine and Hope faults, two major active faults in the South Island, New Zealand. The Alpine Fault is an oblique dextral reverse fault at the late Cenozoic-Recent Pacific-Australian plate boundary. The Hope Fault is a strike-slip fault parallel to the plate convergence vector. Hydrothermal fluids driven by the active tectonic processes have passed through the fractured rock mass, causing localised rock alteration and vein formation. Mylonites in the Alpine Fault zone are crosscut by cm-scale veins of quartz and/or ankerite with minor sulphides, with cemented breccias in dilational jogs. Breccia clasts and immediate (cm-scale) host rocks have been variably impregnated with carbonates and quartz. This generation of veins, breccias and altered rocks is post-dated by cataclasite and fault gouge zones which have been cemented by calcite, illite, smectite and chamosite. Ankerite and calcite have ¹⁸O between +10 and +30, and ¹³C between 0 and –8. These minerals are inferred to have formed from water with variable components of both meteoric and crustally exchanged fluid. Rock alteration associated with ankerite–quartz veins has added arsenic (up to 200 ppm As), strontium, and some Y to the rocks. Host-rock mylonites (<2 ppm As) have been depleted in arsenic compared to their precursors (5–15 ppm As). This depletion of arsenic in the middle crust provides the source for arsenic in shallower-level vein systems.Editorial handling: N. White  相似文献   

Exsolution intergrowths of titanian ferrocolumbite and niobian rutile from the Weinebene Spodumene Pegmatites,Carinthia, Austria     

Dr. P. Černý  Dr. R. Chapman  R. Göd  Dr. G. Niedermayr  Dr. M. A. Wise 《Mineralogy and Petrology》1989,40(3):197-206

Summary Titanian ferrocolumbite is a rare accessory mineral in the spodumene-bearing pegmatites at Weinebene, Carinthia, Austria. It contains abundant exsolved niobian rutile and scarce inclusions of cassiterite that may be primary. The titanian ferrocolumbite is relatively homogeneous with Mn/(Mn + Fe) 0.24–0.33, Ta/(Ta + Nb) 0.09–0.13 (atomic ratios) and 0.47–0.88 Ti per 12 cations (2.7–5.0 wt.% TiO₂). Natural specimens are considerably disordered but become more ordered on heating. Niobian rutile has Mn/(Mn + Fe) 0.00–0.04 and Ta/(Ta + Nb) 0.26–0.38; it concentrates Fe, Ta, Ti and Sn relative to the Mn- and Nb-enriched ferrocolumbite. The overall scarcity of Nb, Ta-oxide minerals in the spodumene-bearing pegmatites of southern Ostalpen conforms to their general features ranking them with the albite-spodumene type of rare-element pegmatites.With 4 Figures  相似文献   

脉金矿床研究进展   总被引：4，自引：0，他引：4  

丁式江  翟裕生 《矿产与地质》1998,12(1):1-6

近年来脉金矿床在成因模式研究方面,有岩浆成因模式,变质模式、地幔去气—麻粒岩化和连续成矿模式等。并着重从成矿流体、矿质来源、沉淀过程和构造背景方面,探讨了脉金产出的地球动力学背景,控矿构造特征,煌斑岩（脉）与金成矿时空关系等。指出我国主要产于花岗岩中的脉金矿床,其流体来源性质,花岗岩中构造对成矿的控制作用,花岗岩的地球动力学背景是值得注意的研究课题。并指出应谨慎对待同位素测年资料。  相似文献   

Isotopic Evaluation on the Genesis of the Kanamaru Pegmatite Deposit, Niigata Prefecture, Japan     

Shunso Ishihara    Koji Hamano  Asami Ikegami 《Resource Geology》1998,48(1):1-6

Abstract: The Kanamaru pegmatite is one of the two largest pegmatite deposits in Japan and is rich in K–feldspar, which is maximum microcline. The mica minerals and microcline from this ore deposit were studied for K-Ar ages and δ¹⁸O ratios. Biotite gives K-Ar age of 78. 5 Ma, but microcline is much younger in age of 66. 0 and 58. 3 Ma. Oxygen isotopic equilibrium temperature of the biotite-quartz pair is 625°C. Using closure temperature of the K-Ar system for biotite and microcline, cooling rate of the pegmatite is calculated to be 88°C/m. y. at the beginning but 12°C/m. y. in the later period of the cooling history. The microcline is slightly depleted in ¹⁸O, yielding apparent equilibrium temperatures of 230°C and 155°C on quartz-microcline pairs. It is suggested that the fluid phase, magmatic and partly meteoric in origin, contained in the solidifying pegmatite, was interacted with the original orthoclase and converted it to microcline during the subsolidus stage.  相似文献   

广西龙胜县柚子坪铅锌矿断裂构造控矿特征及成因探讨     

周宇  李刚  孔凡全  汤静如  黄伟纯 《云南地质》2014,(1):151-155

柚子坪铅锌矿的主要矿体是受F1断裂控制的脉状矿床,其单脉的成矿构造可分为剪切带型与破碎带型两种类型.破碎带型矿脉多呈不规则状,囊状,空间分布与断裂破碎带一致,矿化不均匀且品位低;剪切带型矿脉多呈透镜状,其成矿构造具有平行复脉、脉中脉及矿液压裂等特征,矿化较富集且品位高.工业矿体是由多个破碎带型或剪切型单脉组成的脉群.认为F1断层既是导矿构造,又是储矿构造,多期次的构造运动是形成上述构造特征的主要原因.  相似文献   

云南马关扣哈锡、钨多金属矿成矿远景初探     

王琨  花仁忠  龙洋 《云南地质》2014,(1):19-21

矿区位于云南省东南部,老君山花岗岩北西侧接触带部位上,属南岭花岗岩系列.矿床严格受东西向构造破碎带控制,属典型中高温热液云英岩脉型锡钨矿床.  相似文献   

云南贡山丹珠铌钽多金属矿床地质及找矿潜力     

唐建云 《云南地质》2009,28(3):268-274

丹珠铌钽矿位于怒江褶皱束中部,具有良好的成矿条件和地质构造背景,沿怒江流域呈规律性的纵向展布,长达170余公里。对该矿床深入分析,认为具备大型矿床的成矿条件。因此,加强矿区的综合研究及深部勘探,将会取得突破性进展。  相似文献   

Petrology,geochemistry and source characteristics of the Burpala alkaline massif,North Baikal   总被引：1，自引：1，他引：0  

N.V. Vladykin  I.A. Sotnikova 《地学前缘(英文版)》2017,8(4):711-719

The Burpala alkaline massif contains rocks with more than 50 minerals rich in Zr,Nb,Ti,Th,Be and rare earth elements(REE).The rocks vary in composition from shonkinite,melanocratic syenite,nepheline and alkali syenites to alaskite and alkali granite and contain up to 10%LILE and HSFE,3.6%of REE and varying amounts of other trace elements(4%Zr,0.5%Y,0.5%Nb,0.5%Th and 0.1%U).Geological and geochemical data suggest that all the rocks in the Burpala massif were derived from alkaline magma enriched in rare earth elements.The extreme products of magma fractionation are REE rich pegmatites,apatite-fiuorite bearing rocks and carbonatites.The Sr and Nd isotope data suggest that the source of primary melt is enriched mantle(EM-Ⅱ).We correlate the massif to mantle plume impact on the active margin of the Siberian continent.  相似文献   

Calcite veins as an indicator of fracture dilatancy and connectivity during strike-slip faulting in Toarcian shale (Tournemire tunnel,Southern France)     

《Journal of Structural Geology》2016

The reactivation of faults induced by natural/human induced fluid pressure increases is a major concern to explain subsurface fluid migration and to estimate the risk of losing the integrity of reservoir/seal systems. This study focusses on paleo-fluid migration in a strike slip fault with >100 m long, affecting a Toarcian shale (Causses Basin, France). A high calcite concentration is observed in a 5 cm thick zone at the boundary between the fault core and damage zone. Cumulated displacements in this zone are of millimeter-to-centimeter-scale offsets and different dilatant deformation textures are observed. The zone is affected by thin slip planes containing gouge. Cathodo-luminescence observations indicate that two phases of vein formation occurred. The first phase coincides with the fluid migration along this centimeter thick dilatant zone. The second one is associated to re-shear along the millimeter thick slip planes that results in more localized mineralization, but also in a better hydrologic connection through the shale formation. These results show that in shales fluids may migrate off a slipping surface in centimeter scale dilatant volumes, at first controlled by the intact shale anisotropy related to bedding and then favored by brecciating, structures re-orientation and strengthening processes induced by calcite sealing effects.  相似文献