Global Volcanism Program | Image GVP-05351
This outcrop exposes a thick pyroclastic flow deposit from an eruption that formed a small caldera on the eastern edge of Black Peak volcano. This major eruption occurred about 4,200 to 4,700 years ago and filled adjacent valleys to depths of up to 100 m.
Photo by Tom Miller, 1985 (Alaska Volcano Observatory, U.S. Geological Survey).
This image is made available as a Public Domain Work, but proper attribution is appreciated.