Mammoth Hot Springs

{{Short description|Hot spring complex in Yellowstone National Park, Park County, Wyoming, U.S.}}

{{hatnote|Not to be confused with The Mammoth Site in Hot Springs, South Dakota}}

{{Infobox hot spring

| name = Mammoth Hot Springs

| photo = Dead trees at Mammoth Hot Springs.jpg

| photo_width = 1234

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| photo_caption = Dead Trees at Mammoth Hot Springs

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| map_caption = Map of area

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| location = Mammoth Hot Springs, Yellowstone National Park, Park County, Wyoming

| elevation = {{convert|6735|ft|m}}{{cite web|title=Mammoth Hot Springs, Wyoming|url=http://www.topoquest.com/place-detail.php?id=1609273|website=Topoquest.com|accessdate=16 August 2014}}

| coordinates = {{coord|44|58|01|N|110|42|44|W|display=inline,title}}{{cite gnis |id=1609273 |name=Mammoth Hot Springs}}

| hot_spring_type = Hot spring complex

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Mammoth Hot Springs is a large complex of hot springs on a hill of travertine in Yellowstone National Park adjacent to Fort Yellowstone and the Mammoth Hot Springs Historic District.{{cite rcn|5682|Mammoth Hot Springs}} It was created over thousands of years as hot water from the spring cooled and deposited calcium carbonate (over two tons flow into Mammoth each day in a solution). Because of the huge amount of geothermal vents, travertine flourishes.{{cite web|title=What is Travertine?|url=http://travertineinfo.com/what-is-travertine/|publisher=Travertine Info|accessdate=16 August 2014}} Although these springs lie outside the caldera boundary, their energy has been attributed to the same magmatic system that fuels other Yellowstone geothermal areas.

The hot water that feeds Mammoth comes from Norris Geyser Basin after traveling underground via a fault lineSorey, M.L. 1991. summary and conclusions. In Effects of Potential Geothermal Development in the Corwin Springs Known Geothermal Resources Area, Montana, on the Thermal Features of Yellowstone National Park. M.L. Sorey, ed. U.S. Geological Survey Water-Resources Investigations Report 91-4052, p A1-A17. that runs through limestone and roughly parallel to the Norris-to-Mammoth road. The limestone from rock formations along the fault is the source of the calcium carbonate.{{cite journal|last=Carr|first=B. B. |author2=Jaworowski, C. |author3=Heaslerm, H. P.|title=Mapping Change at Mammoth Hot Springs Using Aerial Photographs and Visual Observations|journal=Yellowstone Science|year=2010|volume=18|issue=3|pages=15–22|url=http://www.nature.nps.gov/geology/gip/web_products/YELL_2009_GIP_Carr_Yellowstone%20Science%20article.pdf|archive-url=https://web.archive.org/web/20140819090152/http://www.nature.nps.gov/geology/gip/web_products/YELL_2009_GIP_Carr_Yellowstone%20Science%20article.pdf|url-status=dead|archive-date=August 19, 2014|accessdate=19 March 2012}}{{Cite web|url=http://www.epod.usra.edu/blog/2004/03/orange-mound-spring.html|title = Orange Mound Spring - EPOD - a service of USRA}} Shallow circulation along this corridor allows Norris's superheated water to slightly cool before surfacing at Mammoth, generally at about {{convert|170|F|C|-1}}. Algae living in the warm pools have tinted the travertine shades of brown, orange, red, and green.{{cite web|title=Yellowstone Geysers - Mammoth Hot Springs|url=http://www.yellowstonenationalpark.com/mammoth.htm|website=YellowstoneNationalPark.com|accessdate=16 August 2014}}

Thermal activity here is extensive both over time and distance. The thermal flows show much variability with some variations taking place over periods ranging from decades to days. Terrace Mountain at Mammoth Hot Springs is the largest known carbonate-depositing spring in the world. The most famous feature at the springs is the Minerva Terrace, a series of travertine terraces. The terraces have been deposited by the spring over many years but, due to recent minor earthquake activity,{{when|date=August 2014}} the spring vent has shifted, rendering the terraces dry.

The Mammoth Terraces extend all the way from the hillside, across the Parade Ground, and down to Boiling River. The Mammoth Hotel, as well as all of Fort Yellowstone, is built upon an old terrace formation known as Hotel Terrace. There was some concern when construction began in 1891 on the fort site that the hollow ground would not support the weight of the buildings. Several large sink holes (fenced off) can be seen out on the Parade Ground. This area has been thermally active for several thousand years.{{cite web|title=Mammoth Area Geologic Highlights|url=http://www.nps.gov/yell/naturescience/geomammoth.htm|archive-url=https://web.archive.org/web/20070216052041/http://www.nps.gov/yell/naturescience/geomammoth.htm|url-status=dead|archive-date=February 16, 2007|publisher=National Park Service|accessdate=16 August 2014}}

The Mammoth area exhibits much evidence of glacial activity from the Pinedale Glaciation. The summit of Terrace Mountain is covered with glacial till, thereby dating the travertine formation there to earlier than the end of the Pinedale Glaciation. Several thermal kames, including Capitol Hill and Dude Hill, are major features of the Mammoth Village area. Ice-marginal stream beds are in evidence in the small, narrow valleys where Floating Island Lake and Phantom Lake are found. In Gardner Canyon one can see the old, sorted gravel bed of the Gardner River covered by unsorted glacial till.