Volcanoes: Prediction and Mitigation
Outline
• Mt. St. Helens
• Long Valley, 1982
• Mt. Pinatubo, 1991
Pre-1980 Eruption Activity - Mt. St. Helens
• Small earthquakes
• Rising bulge on north side
• Occurred for months pre-eruption
Current Monitoring at Mt. St. Helens
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
seismology
DomeCam
gas
Long Valley, 1982
• May 1980– Series of large earthquakes (some magnitude 6)
in area
• 1982 - more earthquakes, evidence of magma rising
Long Valley
Long Valley Warnings
• U.S. Geological Survey issued warning in May, 1982 – Lowest level of alert– House prices dropped 40% immediately– Tourism in ski area dropped
• No eruption• 1990’s, more earthquakes, gas emissions
– No warning issued
Mt. Pinatubo
QuickTime™ and aTIFF (Uncompressed) decompressor
are needed to see this picture.
Mt. Pinatubo, Philippines
• Success for prediction of VEI 6 eruption
• Video
• Bottom line: 300 deaths, $1.5million monitoring– Saved ~20,000 people, $500 million in
evacuated property