Aerial view of dramatic, 260-m-high Cone G, one of several tuff cones inside Okmok Caldera on Umnak Island in the eastern Aleutians. This cone, formed during violent explosions of magma charged with steam and volcanic gas, was formed soon after the cataclysmic collapse of Okmok Volcano about 2000 years ago. Its rilled flanks are common erosional features in hydrovolcanic tuff cones.
Credit: Image courtesy of AVO/USGS.Use Restriction: Please cite the photographer and the Alaska Volcano Observatory / U.S. Geological Survey when using this image.
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