Frozen block of pumice (>50 cm) of White River Ash (WRA) on the rim of Churchill caldera.  Surface fines have been winnowed away since the eruption (846-847 CE); however, a few inches below this surface is solid (frozen) WRA.

Frozen block of pumice (>50 cm) of White River Ash (WRA) on the rim of Churchill caldera. Surface fines have been winnowed away since the eruption (846-847 CE); however, a few inches below this surface is solid (frozen) WRA.

Date: May 20th, 1990
Volcano(es): Churchill, Mt
Photographer: McGimsey, R. G.
URL: avo.alaska.edu/image/view/78541
Image courtesy of AVO/USGS.
Please cite the photographer and the Alaska Volcano Observatory / U.S. Geological Survey when using this image.
Full Resolution.