Volcanoes

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Volcanoes

• By
• Jason Guild
• Victoria Kinney
• Meghan Mercier

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Rationale

• Current event of the eruption of Mt. St. Helens
• Part of NYS Earth Science curriculum

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What is a Volcano?

• An opening in the earths crust through which
  lava and gases erupt.

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Where do Volcanoes Occur?

• Ring of Fire
• Plate Boundaries
• Hot Spots

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What Causes Volcanoes?

• Divergent Boundaries
• Convergent Boundaries
• 1)Oceanic-Oceanic
• 2)Oceanic-Continental
• Hot Spots

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Different Types of Volcanoes

• Shield Cone
• Cinder-Cone
• Composite

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Shield Cone Volcano

• Non-explosive eruption (lava comes out slowly)
• Gentle slopes
• Mainly at hot spots
• Example Hawaii

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Cinder Cone Volcano

• Explosive Eruptions
• Steep Slope
• Built from tephra
• Example El Salvador

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Composite Volcanoes

• Repeated non-explosive and explosive eruptions
• Built from alternating layers of tephra and lava
• Moderate slopes
• Example Mt. St. Helens

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Mount St. Helens 1980

• May 18th, 1980
• 57 deaths
• Flattened 230 square miles of forest land

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Before and After 1980
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Current Mount St. Helens Eruptions

• Lava rising up underneath volcano
• Increased earthquake activity
• Releasing of its pressure through steam
  eruptions.
• Live webcam of Mt. St. Helens

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References

• http//www.fs.fed.us/gpnf/volcanocams/msh/
• www.google.com
• www.volcano.und.edu