View over the West Thumb Geyser Basin. Yellowstone National Park, Wyoming, USA
Percolating Spring in the West Thumb Geyser Basin, Yellowstone National Park, Wyoming, USA.
Perforated Pool in the West Thumb Geyser Basin, Yellowstone National Park, Wyoming, USA. Perforated Pool is one of a group of hot springs in the middle area of the basin that all seem to share a common plumbing system. When major features, such as Abyss and Black pools, are in an active phase, this secondary cluster can be drained of water.