Alaska Volcano Observatory

This is a photograph of Flattop Mountain, a popular peak near Anchorage, AK. The red line shows the equivalent volume of the 2009 Redoubt lava dome - 70 million cubic meters. This volume was calculated by USGS geologist Angie Diefenbach at the Cascades Volcano Observatory, using oblique photos taken by AVO geoscientists.

Credit: The original photograph of Flattop was taken by Jeff Medkeff, and is used here via Creative Commons. Doug Robbins added the Redoubt volume comparison.
Use Restriction: This image may be used with proper attribution to Jeff Medkeff, Creative Commons, and Doug Robbins, Alaska Volcano Observatory.
Full Resolution.