Abstract: Application of Chemical Geothermometers to Thermal Waters of Southwest New Mexico and West Texas

C. A. Swanberg

The sodium, potassium, calcium geothermometer has been applied to thermal spring waters from southwest New Mexico and to nongeothermal ground waters from the Rio Grande basin in West Texas. A prime geothermal prospect in southwest New Mexico is the Radium Springs area, just north of Las Cruces, New Mexico. Reservoir base temperature estimated by the Na-K-Ca geothermometer is in the range 200-220°C, well in excess of published minimum values for economic geothermal development. Further, the springs have an in situ temperature of 85°C, and are associated with tertiary rhyolites and recent faults, also indicating a good geothermal prospect.

In West Texas, the Na-K-Ca geothermometer has been applied to nongeothermal waters collected during ground water investigations of the Rio Grande basin. There is a marked geographic relation between samples yielding high (80-100°C) and low (< 50°C) estimated temperatures. The high-temperature samples are confined to a belt, roughly 100 km wide and extending southeast along the Rio Grande River from El Paso as far south as Marfa, Texas. The low-temperature samples are confined to areas south of Marfa and east of the aforementioned band. These data may correlate with the southern extension of the Rio Grande rift and may also help outline the regions of West Texas having high geothermal potential.

AAPG Search and Discovery Article #90979©1975 AAPG – SEPM Rocky Mountain Sections Annual Meeting, Albuquerque, New Mexico