Puyehue Volcano Eruption, Andes, Chile

Geothermal activity and exploration
Cordón Caulle is a major area of geothermal activity, as manifested by the several hot springs, boiling springs, solfataras and fumaroles that develop on it. The geothermal system in Cordón Caulle consists of a vapour dominated system overlain by a more superficial steam heated aquifer. The temperatures of the vapour systems range from 260–340 °C and 150–180 °C for the aquifer. The uppermost part of the geothermal system, at 1500–2000 m (4,921–6,562 ft), is characterized by fumaroles and acid-sulfate springs. Cordón Caulle is considered one of the main sites of geothermal exploration in Chile.