Mammoth Hot Springs
The Minerva terraces at Mammoth Hot Springs in Yellowstone consist of colorful travertine and tufa that precipitate from the hot water. In contrast to the geyserit that is made of silica, a wealth of small pools develop, each filled with water. The colors result from chemical constituents of sulfur, yellow; iron, red and manganese, brown.
August 1998
Pentax MZ5, Pentax 28mm, f/22, 1/30sec, Kodak Ektachrome E6, ISO 100, tripod