A database on geothermal fluids in Switzerland, called BDFGeotherm, has been compiled. It consists of nine related tables with fields describing the geographical, geological, hydrogeological and geothermal conditions of each sampling location. In all, 203 springs and boreholes from 82 geothermal sites in Switzerland and neighboring regions are listed in this new interactive Microsoft Access database. BDFGeotherm is a functional tool for various phases of a geothermal project such as exploration, production or fluid reinjection. Many types of queries can be run, using any fields from the database, and the results can be put into tables and printed or exported and saved in other files. In addition to describing the database structure, this paper also gives a summary of the reservoir formations, the geographical distribution of hydraulic parameters, the geochemical types of thermal waters and the potential geothermal resources associated with the sites.

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A B S T R A C TThe hydrothermal system of Saint-Gervais-les-Bains, France is located in a south western low-elevation point of the Aiguilles Rouges crystalline Massif. The crystalline rocks are not directly outcropping in the studied area but certainly exist beyond 300 m depth. Uprising waters are pumped from two different aquifers below the Quaternary deposits of the Bon Nant Valley. In the Lower Trias-Permian aquifer crossed by De Mey boreholes (27-36 8C), the ascending Na-SO 4 and high-Cl thermal water from the basement (4.8 g/L) is mostly mixed by Ca-SO 4 and low-Cl cold water circulating in the autochthonous cover of the Aiguilles Rouges Basement. The origin of the saline thermal water probably results from infiltration and circulation in the basement until it reaches deep thrust faults with leaching of residual brines or fluid inclusions at depth (Cl/Br molar ratio lower than 655). The dissolution of Triassic halite (Cl/Br > 1000) is not possible at SaintGervais-les-Bains because the Triassic cold waters have a low-Cl concentration (< 20 mg/L). Water-rock interactions occur during the upflow via north-south strike-slip faults in the basement and later on in the autochthonous cover. For the De Mey Est borehole, gypsum dissolution is occurring with cationic exchanges involving Na, as well as low-temperature Mg dissolution from dolomite in the Triassic formations. The aquifer of imbricated structures (Upper-Middle Trias) crossed by the Lé pinay well (39 8C) contains thermal waters, which are strongly mixed with a low-Cl water, where gypsum dissolution also occurs. The infiltration area for the thermal end-member is in the range 1700-2100 m, close to the Lavey-les-Bains hydrothermal system corresponding to the Aiguilles Rouges Massif. For the Ca-SO 4 and lowCl end-member, the infiltration area is lower (1100-1300 m) showing circulation from the Mont Joly Massif. The geothermometry method indicates a reservoir temperature of probably up to 65 8C but not exceeding 100 8C. R É S U M ÉLe systè me hydrothermal de Saint-Gervais-les-Bains, France est localisé au niveau du point bas du massif cristallin des Aiguilles Rouges, côté sud-ouest. Le socle n'affleure pas directement sur la zone é tudié e, mais est certainement pré sent au-delà de 300 m de profondeur. Les eaux thermales ascendantes sont pompé es dans deux diffé rents aquifè res, sous les dé pôts quaternaires de la vallé e du Bon Nant. Dans l'aquifè re du Permien-Trias infé rieur traversé par les forages De Mey (27-36 8C), une eau thermale ascendante Na-SO 4 riche en Cl issue du socle cristallin (4,8 g/L) est essentiellement dilué e par une eau froide * Corresponding author.E-mail addresses: romain.sonney@crege.ch, romain.sonney@unine.ch (R. Sonney).Ca-SO 4 , pauvre en chlorure, circulant dans la couverture autochtone du socle des Aiguilles Rouges. Cette eau thermale saline se serait infiltré e dans les Aiguilles Rouges et circulerait en profondeur jusqu'aux plans de chevauchement, avec le lessivage de saumures ré siduelles d'inclusions fluides (rapport molair...