Characteristics:
.Prior to 1980, Mount St. Helens formed a conical, youthful volcano sometimes known as the Fuji-san of America
.Prior to 2200 years ago, tephra, lava domes, and pyroclastic flows were erupted, forming the older St. Helens edifice, but few lava flows extended beyond the base of the volcano
.The modern edifice was constructed during the last 2200 years, when the volcano produced basaltic as well as andesitic and dacitic products from summit and flank vents.
Crater from Spirit Lake, tele photo lens, 1988: What appears like volcanic steam (right) is in fact dust caused by rockfalls on the inside of the crater wall. The lava dome (center) is, however steaming slightly
Tree trunk near Windy Ridge, 1988. Note how after only eight years flowers are growing already.
Credits:www.swisseduc.ch/stromboli/perm/msh/photo-en.html
OCTOBER 2004 DOME ERUPTION
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