volcanic_eruptions

							Volcanic Eruptions (or Volcanoes are Cool)

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Types of Eruptions. Types of Volcanoes. Volcanoes and Plate Tectonics.

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Eruptions are Classified as:

 Quiet………or

Violent!

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Quiet Eruptions

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Violent Eruptions

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What causes quiet or violent eruptions?
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The amount of silica in the magma. The amount of water in the magma. Other gases in the magma.

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Basaltic Magma
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Magma composed of basalt. Contains small quantities of water and other gases. Contains small quantities of silica. Minerals contain quantities of iron. Typically quiet eruptions.
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Granitic Magma
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Magma is composed of granite. Contains large quantities of silica. Contains water and other gases. This magma is highly viscous. Eruptions are typically violent.

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Types of Volcanoes: quiet eruptions…
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Shield volcanoes

Galapagos Island

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Shield Volcanoes

Mona Loa, Hawaii

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Shield Volcanoes
Volcanoes of Mars

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Shield Volcanoes
Powerline, Hawaii
Fumarole Butte, Utah

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