Volcanic Eruptions (or Volcanoes are Cool)
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?
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
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
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…
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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