Back scattered electron image of sample AT-3788. This sample is tephra from the Ugashik caldera forming eruption which occurred between 40-171 thousand years ago.
Date: Mar 28th, 2022
Volcano(es): Ugashik-Peulik
Photographer: Lubbers, Jordan
URL:
avo.alaska.edu/image/view/193825
Ugashik-Peulik 171000 yBP
From Miller (2004): "The only isotopically-dated volcanic rocks are dacite from the south rim of the caldera which yielded a single whole-rock K-Ar age determination of 171,000+/-22,000 yrs (table 2 on plate 2 [in original text])."
Image courtesy of AVO/USGS.
Please cite the photographer and the Alaska Volcano Observatory / U.S. Geological Survey when using this image.
Full Resolution.