The behaviour of tungsten in granitic melt-vapour systems

Manning, David; Henderson, Paul

doi:10.1007/bf00373674

Cited by 122 publications

(55 citation statements)

References 20 publications

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“…Strong (1985) explains the presence of Sn-W and Sn-W-U mineralisation relating them with the high content of radioelements in the granites. Manning and Henderson (1984) found a strong correlation between the W and P, as is manifest in veins rich in minerals of Sn-W in the Hercynian granites of Europe (London, 1992). Likewise, Green and Watson (1982) have established the control of the P in the geochemistry of trace elements between the accessory phases and the melt.…”

Section: Discussionmentioning

confidence: 99%

Geochemistry, geochronology and mineralisation potential of the granites in the Central Iberian Zone: The Jalama batholith

2008

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AbstraetThe Jalama batholith (Spain and Portugal) is one ofthe numerous granites ofthe Central Iberian Zone with Sn-and W-associated mineralisation. Gn the basis of petrographical and geochemical characterisation three types of granite have been distinguished: inhomogeneous granitoids, porphyrytic granites and leucogranites, all of these being peraluminous and subalkaline. All the granites correspond to S-type granites. The field data, the petrography and lack of geochemical affinity relationships of the leucogranites with the remaining granites indicate that their geneses correspond to an independent magma batch and superimposed fractional crystallisation process. The granitic units show subparallel REE patterns. There is a decrease in total REE and an increase in the negative Eu anomaly from the inhomogeneous granitoids to leucogranites. Some leucogranites show relatively low contents of Sn and W almost certainly due to segregation in the magma of a melt rich in water carrying Sn-W. These elements are concentrated in the water phase, which eventually gives rise to Sn-W-associated mineralisation.The ages obtained by means of a whole-rock Rb-Sr isochron for the granites mainly indicate an early intrusion of the inhomogeneous granitoids (319 ± 10 Ma), followed in time by porphyrytic granites (279 ± 9 Ma), which can be associated to the late-post-kinematic granites within the third Variscan deformation phase (D 3 ). Apart from the average Sn content, the variations of trace elements, principally Sr, Ba, Rb, Th and P, establish that the porphyritic granites and the inhomogeneous granitoids will be barren granites while the leucogranites and the subfacies at the margin of the porphyritic granites correspond to granites with mineralisation potential. It is precisely in these granites ofthe Jálama batholith that the Sn-W mineralisation is located, for which the criteria utilised has been demonstrated to be effective.

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Section: Discussionmentioning

confidence: 99%

Geochemistry, geochronology and mineralisation potential of the granites in the Central Iberian Zone: The Jalama batholith

2008

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“…Entretanto, os conteúdos de cassiterita e wolframita podem variar em diferentes proporções (Sn > W, Sn ≈ W ou Sn < W), cujos mecanismos físico-químicos responsáveis por essas proporcionalidades ainda são motivos de discussão. Em geral, os pesquisadores consideram a atuação conjunta ou em parte dos seguintes mecanismos: a) variações químico-mineralógicas nos sistemas graníticos portadores de Sn ou W, b) diferenças nos coeficientes de partição entre Sn e W durante o fracionamento, c) diferenças na ação dos voláteis durante o fracionamento, d) tipo de agente complexante responsável pelo transporte de Sn e W nos fluidos hidrotermais, e) taxa de interação entre fluido hidrotermal e rocha encaixante, e f) condições de temperatura, pressão, pH, Eh e fO 2 nos sítios deposicionais (Manning & Henderson 1984 (Zhang et al 1994 Marignac & Cuney 1991, Taylor & Wall 1992e 1993. Tanto cassiterita como wolframita nesses sistemas hidrotermais hospedam exsoluções de nióbio-tantalatos consideradas produtos do abaixamento da temperatura e/ou mudança no estado de oxidação do fluido hidrotermal coexistente.…”

Section: Considerações Finaisunclassified

Composição química e isótopos de oxigênio em cassiterita e wolframita nos greisens do albita granito Palanqueta, depósito de estanho de Bom Futuro (RO)

Souza

Botelho

2009

RBG

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Resumo O Estado de Rondônia hospeda suítes graníticas meso a neoproterozóicas portadores de Sn, W, Nb, Ta, F e gemas, associadas à greisens, veios, brechas e pegmatitos, cujas informações sobre as composições químicas, isotópicas e de inclusões fluidas dos minerais-minérios ainda são discretas. Esse trabalho apresenta estudo sobre a composição química e isotópica (δ 18 O) de cassiterita e wolframita, encontradas nos greisens do albita granito Palanqueta, o qual faz parte do depósito de estanho do Bom Futuro. Nesses greisens os cristais de cassiterita exibem seu característico zonamento, ressaltado por faixas ricas em Sn alternadas por faixas ricas em Fe, Ti, Ta, Nb e W. Por outro lado, os cristais de wolframita mostram-se ricos em Fe em relação ao Mn, com franca migração para o membro ferberita (Fe 0,52-0,86 -Mn 0,10-0,38 ) WO 4 , com baixos conteúdos em Nb, Ta e Sn. Tanto cassiterita como wolframita hospedam micro-inclusões de nióbio-tantalatos, provavelmente produtos de exsolução durante o abaixamento da temperatura. Quanto à composição isotópica (δ 18 O), cassiterita (1,8 e 2,0), wolframita (1,4 e 1,6) e quartzo (9,6) exibem valores discrepantes e indicativos de fracionamento isotópico durante a ascensão dos fluidos responsáveis pela mineralização. Isso porque o quartzo é um mineral pouco suscetível ao fracionamento isotópico, cujo registro ficou melhor diagnosticado em cassiterita e wolframita. A composição isotópica de cassiterita, wolframita e quartzo aplicada para cálculos geotermométricos, assim como para o cálculo indireto da composição isotópica (δ 18 O) do fluido hidrotermal "fóssil" coexistente, estimam que cassiterita e wolframita foram precipitados no intervalo de temperatura de 420 o a 460 o C e a partir do mesmo fluido hidrotermal de derivação magmática.Palavras-chave: cassiterita, wolframita, depósito de estanho do Bom Futuro, Rondônia. Abstract The chemical composition and oxygen isotopes studies in cassiterite and wolframite from greisens of the Palanqueta albite granite, Bom Futuro tin deposit, Rondônia, Brazil. The RondôniaSte hosts Meso-to Neoproterozoic granitic suites associated with important Sn, W, Nb, Ta, F, topaz and beryl mineralization confined in greisens, veins, breccia pipes and pegmatites. However, in these deposits, the chemical and isotopic composition, as well as fluid inclusions data, is still discrete. We provide in this paper new data on chemical and oxygen isotope composition of cassiterite and wolframite from greisens of the Palanqueta albite granite, in the Bom Futuro tin deposit. In these greisens the cassiterite crystals are typically zoned, with nearly pure SnO 2 light zones and high Fe, Ti, Ta, Nb e W dark zones, while the wolframite crystals are relatively Ferich, indicative of the specimen ferberite (Fe 0,38 ) WO 4 , with low contents of Nb, Ta and Sn. Both cassiterite and wolframite host micro-inclusions of Nb-Ta minerals, probably as exsolution product during the lowering of temperature. The oxygen isotope (δ 18O ‰) composition of cassiterite (1.8 -2.0), wolfra...

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“…The available experimental data on tungsten speciation and scheelite solubility in hydrothermal fluids under geologically reasonable conditions are limited (Bryzgalin, 1976;Foster, 1977;Wesolowski et al, 1982Wesolowski et al, , 1984Manning and Henderson, 1984). Even fewer data are available on molybdenum speciation and molybdenite solubility (Smith et al, 1980;Candela and Holland, 1984).…”

Section: Physiochemical Controls On Scheelite and Molybdenite Depositionmentioning

confidence: 99%

“…Wesolowski et al (1982Wesolowski et al ( , 1984, conclude from experimental data that HWO; and ~0 ; ' are the dominant tungsten species at elevated temperatures in moderately saline solutions of slightly acidic to basic pH. Although Higgins (1980), on the basis of fluid inclusion data for tungsten vein deposits, suggested that tungsten may form carbonate and bicarbonate complexes in C02-rich fluids, Manning and Henderson (1984) do not consider these as viable means of tungsten transport. However, they conclude from their ex~erimental work at 800°C and 1 kb that complexing with chlorine may be important in tungsten transport in hydrothermal fluids and suggest that ( W 0 3 ) 2 C l may be the dominant species at low chloride concentrations.…”

Section: Physiochemical Controls On Scheelite and Molybdenite Depositionmentioning

confidence: 99%

Stockwork tungsten (scheelite)-molybdenum mineralization, Lake George, southwestern New Brunswick

Seal¹,

Clark²,

Morrissy³

1987

Economic Geology

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Scheelite-molybdenite stockwork mineralization constitutes one component of the Lake George polymetallic (Sb-W-Mo-Au-base metal) deposit, a complex hydrothermal center of Late Silurian (ca. 412 m.y.) age in the Fredericton trough of the northern Appalachians. The stockwork, hosted by Silurian gra~wackes, in part calcareous, is spatially and temporally related to a postkinematic cupola of biotite monzogranite, and its formation overlapped in time with the emplacement of monzogranitic porphyry dikes. Mineralogical and textural evidence indicates that contact metamorphism associated with the cupola had ceased before the initiation of W-Mo mineralization and that it occurred, at pressures of less than 1.75 kb, in two stages: a peak stage (T > 600°C), evident only in rocks of pelitic composition; and a lower temperature reequilibration (T < 500°C), recorded in rocks of both pelitic and marly compositions.The W-Mo deposit comprises three different scheelite-and/or molybdenite-bearing veinlet types. Type 1 bodies, the earliest formed, are calc-silicate (granditic garnet, wollastonite, ~l i n o p~r o x e n e , and calcic amphibole) quartz veinlets, with ubiquitous Ca and H metasomatic alteration envelopes. Mineralogical and fluid inclusion relationships indicate that the fluids ranged in temperature from 550° to 22B°C and that temperature decreased away from the cupola. The succeeding type 2 veinlets comprise quartz and lesser amounts of perthitic alkali feldspar, muscovite, calcite, scheelite, molybdenite, and pyrite. Fluid inclusion evidence shows that mineralization dominantly occurred from 400' to 175OC, under a confining pressure of 1.3 kb. Higher grade scheelite and molybdenite deposition was focused in a lower temperature zone, to the north of the cupola, in which CO, effervescence occurred. Type 3 veinlets, the last to form, consist of prehnite, mol~bdenite, and quartz and represent a volumetrically minor mineralization type.In both type 1 and 2 systems, scheelite and molybdenite deposition appears to have been controlled by decreasing temperature and increasing pH. Temperature was a function of distance from the cupola for both veinlet types, but the controls on pH were specific to each. Thus, the pH of type 1 fluids was controlled by wall-rock interaction (H metasomatism), whereas that of type 2 fluids was controlled by CO, effervescence.The economic stibnite-quartz veins (Scratch et al., 1984) occupy fractures which transect, and therefore, postdate all stages of W-Mo mineralization.

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The behaviour of tungsten in granitic melt-vapour systems

Cited by 122 publications

References 20 publications

Geochemistry, geochronology and mineralisation potential of the granites in the Central Iberian Zone: The Jalama batholith

Geochemistry, geochronology and mineralisation potential of the granites in the Central Iberian Zone: The Jalama batholith

Composição química e isótopos de oxigênio em cassiterita e wolframita nos greisens do albita granito Palanqueta, depósito de estanho de Bom Futuro (RO)

Stockwork tungsten (scheelite)-molybdenum mineralization, Lake George, southwestern New Brunswick

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