Mammoth Hot Springs, Yellowstone National Park

This photograph shows the unique hot springs terraces found primarily at the Mammoth Hot Springs area of Yellowstone National Park (Wyoming). These are formed when very hot water rises through underground limestone, depositing minerals on the surface. Over time, these fascinating terraces grow, constantly changing due to varying water flows. When active, they may show yellows, greens, and oranges, but are otherwise a chalky gray or white.