Colorful Mammoth Hot Springs • Several key ingredients combine to make the Mammoth Hot Springs Terraces: heat, water, limestone, and a rock fracture system through which hot water can reach the earth's surface. Another necessary ingredient for terrace growth is the mineral calcium carbonate. Thick layers of sedimentary limestone, deposited millions of years ago by vast seas, lie beneath the Mammoth area. Mammoth Hot Springs, like any living organism, it constantly evolving and changing over time, shedding old skin and growing new layers and morphing into something different.
Many of the bright colors found in Yellowstone's hydrothermal basins come from "thermophiles" — microorganisms that thrive in hot temperatures. So many individual microorganisms are grouped together—trillions!—that they appear as masses of color. Different types of thermophiles live at different temperatures within a hot spring and cannot tolerate much cooler or warmer conditions. Yellowstone's hot water systems often show distinct gradations of living, vibrant colors where the temperature limit of one group of microbes is reached, only to be replaced by a different set of thermophiles. |
