GeologyCafe.com
Distribution of 4 Late Quaternary volcanic tephra layers
(ash, cinders, pumice) over the western United States


Map of 4 tephra layers in the western U.S.
Map prepared by Andrei Sarna-Wojcicki, USGS.
Return to main page
This page is <http://geologycafe.com/california/maps/tephra.htm>
Maintained by Webmaster
Last modified 12/18/2005