Cliff Geyser along Iron Creek in the Black Sand Basin is seen October 8, 2012 in Yellowstone National Park in Wyoming. The geyser formed a rim or wall-like ridge of sinter around its crater from which it erupts 30 to 40 feet high. Yellowstone protects 10,000 or so geysers, mudpots, steamvents, and hot springs. (Photo by Karen Bleier/AFP Photo)
