Near-vertical view of the east Ukinrek Maar crater, 300 m (980 ft) across, that formed in 1977 during a 10-day phreatomagmatic eruption in the Becharof National Wildlife Refuge on the Alaska Peninsula. Part of smaller west Ukinrek Maar crater is visible at upper left. Photograph by D. Dewhurst, U.S. Fish and Wildlife Service, July 8, 1990.
Image courtesy of the photographer.