travertine,Mammoth Hot Springs,White Elephant Terrace,Yellowstone NP,snags; limestone, photo

White Elephant Terrace Snags

Yellowstone NP

The step-like terraces form as heated water moves along the Morris-Mammoth Fault. The hot water carries dissolved calcium and bicarbonate to the surface of the terraces where pressure lessens. Carbon dioxide then escapes as gas and the carbonate combines with calcium to precipitate as travertine. Photo © copyright by Robert Faucher.

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