Travertine terraces at Mammoth Hot Springs, Yellowstone National Park in winter
Travertine terraces are formed from thermal water rising through limestone. Heat-loving bacteria and algae add vivid colors to the chalky-white travertine.
Unusual green and pink colors caused by thermophilic microbes
Unusual colors in the travertine terraces are caused by thermophilic microbes
Upper travertine terraces at Mammoth Hot Springs, Yellowstone National Park in winter
Tree line at sunrise in Yellowstone's Lamar Valley
Moose feeding on willows in Yellowstone's Lamar Valley
Dead trees encased in the deposits from Mammoth Hot Springs
Snow-covered travertine terraces at Mammoth Hot Springs
Motion blur of the Bobby Socks Trees of Yellowstone in Winter