Muddy thermal discharge near Congress Pool in Norris Geyser Basin following the 1975 Yellowstone National Park earthquake
Muddy thermal discharge near Congress Pool in Norris Geyser Basin following the 1975 Yellowstone National Park earthquakeMuddy thermal discharge (foreground) near Congress Pool (middle ground) in Norris Geyser Basin following the June 30, 1975, magnitude-6 Yellowstone National Park earthquake, NPS photo by Rick Hutchinson.