WATER CHEMISTRY AS AN AID IN RECONNAISSANCE EXPLORATION FOR A LOW-TEMPERATURE GEOTHERMAL SYSTEM, ARTESIAN CITY AREA, IDAHO

Water geochemical data can be usefully applied in the reconnaissance stage of exploration for low-temperature geothermal systems. This paper presents the use of these data in conjunc tion with the hydrologic and geologic interpre tation of Struhsacker et al. (in prep.) to predict recharge areas, flow paths, and subsurface temper atures of thermal water in the Artesian City area, Idaho. The source of recharge of the thermal water was determined to be meteroic water derived from the Rock Creek Hills and heated by the geothermal gradient. Interpretation of Na-K-Ca(-Mg) and Si02geothermometer temperatures in the context of proposed flow systems and fluid sources indicates that the predicted temperatures are high and that the thermal water probably cooled from temper atures not much higher than their discharge tempera tures