Fountain Geyser is a

geyser A geyser (, ) is a spring with an intermittent water discharge ejected turbulently and accompanied by steam. The formation of geysers is fairly rare and is caused by particular hydrogeological conditions that exist only in a few places on Ea ...

in the

Lower Geyser Basin The geothermal areas of Yellowstone include several geyser basins in Yellowstone National Park as well as other geothermal features such as hot springs, mud pots, and fumaroles. The number of thermal features in Yellowstone is estimated at 10 ...

Yellowstone National Park Yellowstone National Park is a List of national parks of the United States, national park of the United States located in the northwest corner of Wyoming, with small portions extending into Montana and Idaho. It was established by the 42nd U ...

in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. Fountain is the dominant member of a group of geysers at the Fountain Paint Pots thermal area. Morning Geyser, which erupts from a vent close to Fountain's, is larger, but is inactive during most years. Fountain, by contrast, is usually active. It is a fountain-type geyser that erupts jets ranging in height up to or more, with most eruptions containing at least a few bursts that reach 40 to 50 feet. Intervals (= eruption start to eruption start) vary from year to year but are commonly about 4.5 to 6 hours, with occasional longer intervals of 11 to 12 hours. Durations of eruptions are typically about 30 minutes. Occasionally, Fountain departs from its usual behavior and enters so-called "wild-phase" eruption, during which the height is much reduced but the duration can be as long as two weeks. Fountain is not to be confused with similarly named, and nearby (and larger), Great Fountain Geyser, another of the major features of Lower Geyser Basin, adjacent to the Firehole Lake road.

References

{{Wyoming Geysers of Wyoming Geothermal features of Teton County, Wyoming Geothermal features of Yellowstone National Park Geysers of Teton County, Wyoming