Global Volcanism Program | Image GVP-05342
This view looks south across the caldera from the north rim of Aniakchak. Surprise Lake and its outlet are visible at the upper left. The prominent dark peak on the skyline is Black Nose, a high-standing remnant of pre-caldera volcaniclastics. Hummocky ground in the distance against the caldera wall is a pumice-covered glacier and associated moraine. Surprise Lake once covered a much larger part of the caldera floor before catastrophically draining through a notch in the east caldera rim.
Photo by Tom Miller, 1985 (Alaska Volcano Observatory, U.S. Geological Survey).