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Résumé Le gisement d'Enguialès est situé dans des schistes métamorphiques à proximité du granite de la Margeride et se présente sous la forme de deux systèmes de filons se recoupant l'un l'autre. Le champ filonien et la région avoisinante ont été l'objet d'une étude structurale qui a montré que les filons minéralisés correspondent à des éléments structuraux bien définis. Les filons du premier système sont parallèles à la schistosité S
1 (filons subconcordants) tandis que les filons du deuxième système sont logés dans les diaclases ac.
The Enguialès wolframite deposit (French Massif Central) is located in a metamorphic environment near the Margeride granitic pluton. The deposit is built up of two sets of parallel wolframite-bearing quartz veins crosscutting each other. A structural analysis of the vein system and its environment revealed that the two principal directions of the veins correspond to well-defined structures. The first set of veins is parallel to the schistosity S 1. The second set of veins is an ac-joint filling.相似文献
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This method has been developed for the determination of tungsten in silicate rocks containing resistant minerals. The method consists of fusion of the sample with lithium metaborate, followed by evaporation with hydrofluoric acid in order to remove silicon. Thereafter the residue is treated with concentrated hydrochloric acid. By the reaction of tungsten with dithiol, a blue-green complex is formed. This is extracted with petroleum spirit and its absorption is measured in a spectrophotometer. This method was found to provide a thorough sample attack and an adequate determination of tungsten. 相似文献
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