The scheelite skarn deposit of Salau (Ariege, French Pyrenees)

Abstract

Between 1971 and 1986 the scheelite deposit of Salau, located in the French Hercynian Pyrenees, produced 930,000 metric tons of ore with 1.50 percent WO3 (13,950 metric tons of WO3).The skarn deposit is hosted in a Devonian carbonate and partly detrital series intruded by a late Carboniferous stock. In the Devonian series (the lithostratigraphy and geochemistry of which is described in some detail) a unit of so-called "Barregiennes" (i.e., rythmic alternations of limestones and silts) appears to be very favorable for extensive development of skarns and overprinted ores.The Hercynian orogeny involved polyphase deformation, regional metamorphism of greenschist facies, and late intrusions of granite-granodiorite. Deformation included two coaxial stages of tight isoclinal folding and one important later stage which partly controlled the intrusion of the granodiorite stock, followed by three stages of brittle deformation. Ore deposition is related to faulting stages 0 and 1 and orebodies are cut into slices by stage 2 reverse faults.The Salau intrusion includes various rock types belonging to two slightly different calcalkaline trends. One of these trends, characterized by its low K contents, is unusual in the Pyrenees. The local shapes of the intrusion, apophyses and embayments, are important controls of the orebodies. After isochemical contact metamorphism, the skarns and ores developed in two mainstages related to the infiltration of two quite different types of fluids. During the first stage (540 ø-450øC), anhydrous skarn formation was followed by an intergranular development of pyrrhotite-scheelite-quartz-calcite in equilibrium with the earlier hedenbergite. The resulting tungsten grade is uneconomic. The associated fluids, probably of magmatic origin, had a high salinity. In the second stage (450ø-350øC), no new skarn formed; transformations of the silicate rocks are observed. A first substage of epidotization was followed by the development of intermediate grossularite-almandine-spessartite garnet and finally by the main ore stage 0361-0128/89/959/1172-2853.00 1172 SALAU SCHEELITE DEPOSIT, FRENCH PYRENEES 1173with scheelite, pyrrhotite, arsenopyrite, and other sulfides with some gold. Two types of fluid inclusions are found in this stage; one is similar in composition to the first stage, the other is characterized by low salinity and high CO2 and CH4 contents.

The Salsigne Au-As-Bi-Ag-Cu Deposit, France

“…commun., 2003) or the gold-bearing tungsten skarns of Salau (French Pyrenees; Fonteilles et al, 1989). commun., 2003) or the gold-bearing tungsten skarns of Salau (French Pyrenees; Fonteilles et al, 1989).…”

The world-class Jiangnan tungsten belt: Geologicalcharacteristics, metallogeny, and ore deposit model

“…[2,35~38] , 而东源和阳储 岭的主矿体在成矿主岩花岗闪长岩体和二长花岗斑岩 体中 [5,39] . Wu等人 [40] [50,51] 、法国Salu和 Castabone矽卡岩型钨矿有关的花岗质岩石类似 [52] , La/ Yb比值高, Eu亏损不明显, 但具有Nb、Ta、P和Ti亏损, 表明来源于深部或者有较多地幔物质进入岩浆系统. 、韩国的Weo-lag和Dae Hwain矿床 [59,60] .…”

Neocratonic magmatic‐sedimentary basins of post‐Variscan Europe and post‐Kanimblan eastern Australia generated by right‐lateral transtension of Permo‐Carboniferous Pangaea

“…Cf. Skane dykes and other magmatic rocks in Scandinavia: 300 M a and 288-296 Ma (Priern et al, 1968); Cornubian granites (Willis-Richards 81 Jackson, 1989); Alpine-Moldanubian granites (Finger & Steyrer, 1990, 1991; Massif Central (Duthou et al, 1984, p. 137); Pyrenees granites (Fonteilles et d., 1989;Gilbert & Rogers, 1989); Moroccan granites (Gasquet et al, 1992).…”