The World of Volcanoes

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The World of Volcanoes

• Mrs. Lozano

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What is a volcano?

• A mountain formed by lava and ash

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What is Lava?

• Lava is magma that reaches Earths surface

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• Okay...I know what lava is, but what exactly is
  Magma?
• Magma is hot, soft rock from Earths mantle.

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What is ash?

• Ash is small pieces of hardened lava

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• Savage Earth Animation

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How do volcanoes form?

• Continental plates and oceanic plates collide
• Subduction occurs
• Melted rock becomes magma that forces its way up
  between the plates
• Savage Earth Animation 2

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How do volcanoes form?
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Continental Drift

• Continental Drift Animation

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Where are these Subduction Zones?

• Many volcanoes are located at plate boundaries
  around the Pacific plate.
• The Pacific plate is often called the Ring of
  Fire

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Do all volcanoes look the same?

• No, there are many different kinds of volcanoes
  such as
• Shield Volcanoes that can be found in Hawaii

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• Cinder Cone Volcanoes can be found in Costa Rica

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• Composite Volcanoes like Mt. Saint Helen

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• And Fissure Volcanoes found in Nicaragua .

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Do subduction zones create all volcanoes?

• No, volcanoes can also be formed by Hot Spots.
• Hot Spots are volcanic areas on the surface of
  the Earth that are created by a rising plume of
  magma.
• http//www.classzone.com/books/earth_science/terc/
  content/investigations/es0810/es0810page03.cfm

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Volcanic Hazards

• Volcanoes can create landslides that bury land,
  homes and sometimes people.

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Volcanic Hazards

• Volcanoes can create Earthquakes that may produce
  hazards which include ground cracks, ground
  deformation, and damage to manmade structures.

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Volcanic Hazards

• Pyroclastic Surge that spews extremely hot ash
  that races down the mountain and swallows
  everything in its path.

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Volcanic Hazards

• Lava flows are the most famous yet the least
  dangerous of hazards.

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Volcanic Hazards

• There are two kinds of lava flows
• Pahoehoe
• AA

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I love Volcanoes!!!!!!

• Although volcanoes are beautiful and wondrous
  things, they can be harmful and cause many
  disasters. It is better to love volcanoes from a
  far off distance.