Landform 3 - geysers

Geysers are produced when a heat source under the Earth's surface, usually a magma chamber, heats water on its way up to the surface. Thy are therefore defined as minor forms of extrusive volcanic activity. When not active, they may look like a bubbling pool of hot water; however, when the pool fills up with superheated water then the geyser will erupt in a plume of boiling water and steam. These features can be found in many locations, including New Zealand, Iceland (where Geysir, which gave its name to these features, is found), and Yellowstone National Park in the USA, where the geyser Old Faithful (below) is a popular and regularly-erupting tourist attraction.

Click here to watch Strokkur erupting several times in sequence.

More information about Strokkur in Iceland and Lady Knox geyser in New Zealand can be found on the respective pages of this site.