Bob Fournier (left) and Don White (right) at the Y3 drilling site in Yellowstone National Park
By Yellowstone Volcano Observatory
1967 (approx.)

Detailed Description
Bob Fournier (left) and Don White (right) at the Y3 drilling site in Pocket Basin adjacent to Ojo Caliente, Lower Geyser Basin, Yellowstone National Park, in 1967. USGS Photo.
Sources/Usage
Public Domain.