of Mount Saint Helens who blew her top on 18 May 1980 after a 123 year period of quiescence. The aerial image above (click to enlarge) shows the dominant north-side breach that was opened in the initial moments of the eruption sequence that began at 8:32 am local time. A 5.1 magnitude earthquake triggered the largest landslide ever recorded, and as the north flank of the volcano collapsed the pressurized magma was free to expand thereby creating an enormous directed blast that nearly instantaneously leveled ~220 square miles of forest.In addition, the rhyodacite lava dome is easily seen in the crater, as well as the runout of the Pine Creek lahar on the southeast side of the edifice that was fed by the melting Shoestring Glacier. Subsequent lava domes have been constructed during 2004-2006.
Links to current status, a brief summary article, and a photo gallery.
Image credit: NASA
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