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

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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

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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