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Hydrothermal Research


The Mammoth hot spring terraces are fed by water moving along an extensive fault zone that runs north from Norris Geyser Basin, 21 miles (34 km) away. The water cools somewhat en route. Extremely hot water is necessary for geysers; in Mammoth, the water isn’t even hot enough to boil. The bubbling water seen in many of the area's hot springs doesn't indicate great heat, but rather the presence of carbon dioxide gas.

Mammoth Hot Springs terrace The average water temperature at Mammoth is 85° F (29° C), much cooler than the Upper Geyser Basin's average water temperature of 180° F (82° C).
The terraces change constantly-and sometimes overnight. Here, as in few other places on Earth, rock forms right before your very eyes!
a travertine formation looks similar to icicles

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Drawing of the outside of the visitor center
Young Scientists
Yellowstone Express
Why Geysers Erupt
Hot Water Treasures
Hot Spring Ecology
Scientific Research

This work is supported by

National Science Foundation    Yellowstone Park Foundation
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