Water and gases are ejected from the cracks in the Earth through a continuous jet called ‘Fumaroles’ and though intermittent jets called ‘Geysers’.
Industry makes use of fumaroles as a source of both, thermal energy and boric acid. Geysers or hot springs occasionally spurt jets of water and stream into the air. These jets sometimes exceed 100 degrees of heat and rise as high as 50 mts at intervals of a few minutes to several hours. This is why the hot springs occur in some areas.
Below Hot Springs info from Wikipedia (Read More):-
A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are hot springs all over the earth, on every continent and even under the oceans and seas.
Hot springs range in flow rate from the tiniest "seeps" to veritable rivers of hot water. Sometimes there is enough pressure that the water shoots upward in a geyser, or fountain.
A very low flow rate hot spring fed the closed resort, Fales Hot Ditch, which is north of Bridgeport, California. There is a huge subterranean lake below Tonopah, Arizona, which provides natural hot mineral waters to several hot springs. These hot springs were used by the seven or more hot spring spas that once operated in Tonopah. The ruins of two such spas are still visible in Tonopah.
http://en.wikipedia.org/wiki/Hot_springs
