Aerial view of Mount St. Helens from the south, showing one of several steam and ash eruptions. Skamania County, Washington. 1980.
Dates
Date Taken
1980
Summary
Caption: Mount St. Helens spews steam and ash. April 12, aerial view of Mount St. Helens from the south, showing one of several steam and ash eruptions that occurred during the day. This eruption occurred about two weeks after the initial eruption on March 27 at this Cascade Mountain Range volcano and about five weeks before the major eruption on May 18. USGS scientists have estimated that a minimum of one cubic kilometer (1.3 billion cubic yards) of ash and rock was ejected by the volcano during that Sunday morning eruption. In comparison, Mt. Vesivius produced slightly more than one cubic kilometer in its eruption that buried Pompei in 79 A.D. The eruption of Indonesia's Krakatoa in 1883 produced about 20 cubic kilometers of ash. [...]
Summary
Caption: Mount St. Helens spews steam and ash. April 12, aerial view of Mount St. Helens from the south, showing one of several steam and ash eruptions that occurred during the day. This eruption occurred about two weeks after the initial eruption on March 27 at this Cascade Mountain Range volcano and about five weeks before the major eruption on May 18. USGS scientists have estimated that a minimum of one cubic kilometer (1.3 billion cubic yards) of ash and rock was ejected by the volcano during that Sunday morning eruption. In comparison, Mt. Vesivius produced slightly more than one cubic kilometer in its eruption that buried Pompei in 79 A.D. The eruption of Indonesia's Krakatoa in 1883 produced about 20 cubic kilometers of ash.
USGS scientists also say that the initial volcanic blast occurred with a force that was equal to 10-50 megatons of TNT or roughly 500-2,500 times more powerful than the blast at Hiroshima at the end of WWII. The first 24 hours of the Sunday eruption released the energy equivalent of up to 500 megatons of TNT.
Available in the U.S. Geological Survey Denver Library Photographic Collection, 2010 DENPH0011, PIO Collection.
Rights
This USGS product is considered to be in the U.S. public domain. For further information on the USGS Information Policies and Instructions, refer to the Copyrights and Credits section on this web page: http://www.usgs.gov/laws/info_policies.html