Summit caldera of Herbert volcano in the Islands of Four Mountains (IFM) Aleutians. This rarely visited and little known volcano shows evidence of youthful eruptions, although none are known in historic time. The small patch of wasting glacial ice at lower left has receded in the last few decades to expose active fumaroles (lower right, light colored patch of ground). Photo taken during the 2014 field season of the Islands of Four Mountains multidisciplinary project, work funded by the National Science Foundation, the USGS/AVO, and the Keck Geology Consortium.
Image courtesy of the AVO/UAF-GI.