Novarupta - The Most Powerful Volcanic Eruption of the 20th Century
http://geology.com/novarupta/
http://en.wikipedia.org/wiki/Novarupta
http://www.volcano.si.edu/world/volc...?vnum=1102-18-

Bigger then Mount Pinatubo in the Philippines 1991
http://en.wikipedia.org/wiki/Mount_Pinatubo

Bigger then Mount St Helens in Washington State USA 1980
http://en.wikipedia.org/wiki/Mount_St._Helens

NASA - In June 1912, Novarupta—one of a chain of Volcanoes
on the Alaska Peninsula - Erupted in what turned out to be the
largest blast of the Twentieth Century.
http://science.nasa.gov/headlines/y2..._novarupta.htm

USGS collection of descriptions of Novarupta
http://vulcan.wr.usgs.gov/Volcanoes/...novarupta.html

Katmai National Park and Preserve
http://en.wikipedia.org/wiki/Katmai_...k_and_Preserve
http://www.nps.gov/katm/upload/Novar...2007%20WEB.pdf

Alaska Volcano Observatory
http://www.avo.alaska.edu/volcanoes/...eruptionid=456

Alaska - http://en.wikipedia.org/wiki/Alaska

Question - Can Another Great Volanic Eruption Happen in Alaska ?
http://pubs.usgs.gov/fs/fs075-98/