Yellowstone Geysers

           

Geysers are hot springs that erupt periodically. The eruptions is the result of super-heated water below-ground becoming trapped in channels leading to the surface. Hot Springs are similar to geysers, but their underground channels are large enough to allow rapid circulation of water. Much of Yellowstone sits inside an ancient volcanic caldera (the exploded crater of a volcano). The last major caldera forming eruption occurred 600,000 years ago.

Yellowstone National Park is home to some 10,000 thermal features, over 500 hundred of which are geysers. In fact, Yellowstone contains the majority of the worlds geysers. Within Yellowstone’s thermal features can be seen the product of millions of years of geology at work. Fumaroles are holes or vents from which steam rushes into the air. It is like a hot spring, but lacks liquid water. Either there isn’t enough water or the underground rock is too hat and boils off all of the water so a pool can’t form.