Mt. St. Helens, Washington

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Mt. St. Helens, Washington
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Plug
Plug
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Cascades
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Bomb
Aerodynamically shaped
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Pyroclastic Flow
gt1000oF gt100MPH Poisonous gas
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Mount Pelee 1902
Damage done by pyroclastic flow
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St. Helens 1
Mt. St. Helens eruption

• First signs of an eruption
• 1) Gas emissions, the more the
• better.
• 2) Increased seismic activity.

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St. Helens Bulge
Bulge grew up to 3 feet per day!
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St. Helens Lateral Blast
Bulge collapsed, resulting in a large landslide.
Magma chamber exposed.
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St. Helens Main Blast
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(No Transcript)
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St. Helens Before
Mt. St. Helens before
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St. Helens After
Mt. St. Helens after.
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Mt. Rainier
4X Mt. St. Helens Steepest part of mountain faces
Seattle
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Villarrica volcano, Chile
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Lahar
Hot mud flow
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Nevado del Ruiz volcano
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Lahar
Consistency of flowing concrete
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Village
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Rainier Lahars
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Rainier Lahars
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Volcanoes of The World
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Famous Volcanic Eruptions
Year without a summer in NE
Sound heard 4000 miles away
Largest eruption in past 100 years
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Caldera Volcanoes
Yellowstone Eruption every 600,000 years Last
eruption 2500km3 of material Toba 90,000 years
ago. Reduced Earths human population to about
5000 people.
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Long Valley Caldera Map
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Long Valley Caldera
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Caldera Collapse
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Bishop Tuff
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Yellowstone Hot Spot
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Yellowstone
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Yellowstone Fallout
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Volcanic Aerosols
SO2
Mt. Pinatubo, 1991 20 tons 1.50F cooling for
two years Tambora, 1815 gt100 tons 20F cooling
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Zones of Volcanism