Echinus Geyser is a

geyser A geyser (, ) is a spring characterized by an intermittent discharge of water ejected turbulently and accompanied by steam. As a fairly rare phenomenon, the formation of geysers is due to particular hydrogeological conditions that exist only ...

in the

Norris 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 10,0 ...

Yellowstone National Park Yellowstone National Park is an American national park located in the western United States, largely in the northwest corner of Wyoming Wyoming () is a state in the Mountain West subregion of the Western United States. It is border ...

in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

History

Echinus was named during one of the U.S. Geological Surveys of the park in the late 1870s or early 1880s. The name Echinus comes from the spiny appearance of the cone that resembles a

Sea urchin Sea urchins () are spiny, globular echinoderms in the class Echinoidea. About 950 species of sea urchin live on the seabed of every ocean and inhabit every depth zone from the intertidal seashore down to . The spherical, hard shells (tests) ...

or class ''

Echinoidea Sea urchins () are spiny, globular echinoderms in the class Echinoidea. About 950 species of sea urchin live on the seabed of every ocean and inhabit every depth zone from the intertidal seashore down to . The spherical, hard shells (tests) of ...

''.

Eruption

Echinus' eruptions are unpredictable. Its fountain reaches a height of as much as , with a duration of about 4 minutes. Prior to 1998, this geyser was very regular, every 35 to 75 minutes. There were also major eruptions that lasted as much as 118 minutes. It is speculated that there was a secondary underground water source that used to power the major eruptions and that the connection to the source was severed leading to Echinus' current state. In October 2017, Echinus Geyser began to show signs of growing activity, with possible eruptions every 2-3 hours. In January 2018, Echinus' last eruption was recorded of this active phase. One recorded eruption occurred in January 2019. Echinus is the largest acid-water geyser in the world. Its waters have a pH of 3.3 to 3.6, nearly as acidic as

vinegar Vinegar is an aqueous solution of acetic acid and trace compounds that may include flavorings. Vinegar typically contains 5–8% acetic acid by volume. Usually, the acetic acid is produced by a double fermentation, converting simple sugars to ...

. The water temperature is . File:EchinusGeyser-Good1965.jpg, Echinus Geyser Pool, 1965 File:Echinus2018.jpg, Echinus on June 9, 2018

References

{{Wyoming Geysers of Wyoming Geothermal features of Park County, Wyoming Geothermal features of Yellowstone National Park Bodies of water of Park County, Wyoming