Sollipulli

The Alpehue geothermal field, about southwest of Alpehue crater, is unusual among the southern Chilean geothermal fields as it features geysers. It lies within a glacial valley presently traversed by the Allipén River, which has cut a vertical canyon into the Nevados de Sollipulli volcano, close to the intersection between two faults. Geothermal features include "spouters", geysers, hot springs and mud pools, as well as geyserite and sinter deposits that form small terrace structures. Geyser columns reach height when they erupt. The geyser field has a total heat output of about 3.3 megawatts and has been active since at least 7,400 years. The deep incision and fractured rocks may facilitate the ascent of geothermal waters.