Geothermal activity
Activity resulting from underground heat / From Wikipedia, the free encyclopedia
Geothermal activity is a group of natural heat transfer processes, occurring on Earth's surface, caused by the presence of excess heat in the subsurface of the affected area.[2] Geothermal activity can manifest itself in a variety of different phenomena, including, among others, elevated surface temperatures, various forms of hydrothermal activity, and the presence of fumaroles that emit hot volcanic gases.