Groundwater from snow melt and other precipitation is heated by molten rocks or magma below the surface. Once heated, the water finds a path through cracks and fissures of lava flows to the surface, where it emerges in geysers, hot springs, mudpots, and fumaroles. A geyser is a vent in Earth’s surface that periodically ejects a column of hot water and steam. Even a small geyser is an amazing phenomenon;
The body of water housing hot springs can vary in size. Geysers are extremely rare features.
Strokkur is one of Iceland’s amazing geysers erupting about every 4-8 minutes 15 – 20 m high, sometimes up to 40 m high.