The 3 types of volcanoes

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Volcanoes
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What is a volcano?

• VOLCANO vents or fissures in the earth's crust
  through which gases, molten rock, or lava , and
  solid fragments are discharged.

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What is the difference between lava and magma?

• Magma- if it is inside of a volcano.
• Lava-if it is outside of a volcano.

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What is AA?

• Lava that is very thick and flows
• s-l-o-w-l-y

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What is Pahoehoe?

• Hot fast moving lava.
• From quiet eruptions.

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What is pillow lava?

• Lava that cools underwater

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What is block lava?

• Cool stiff lava that dries to form pieces with
  jagged edges.

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Silica

• A mineral that is found in lava

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Effects of silica

• More silica more stiff and more color (dark
  lava)
• Less silica less stiff (runny) and light in color

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Cinder cone volcanoes
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• A Strombolian eruption a cinder cone
  volcano

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Cinder cone volcanoes

• Small with steep slopes (but not as steep as a
  composite volcano)
• pyroclastic material-when the magma explodes from
  the volcano and dries before hitting the ground
• Made of cinder and pyroclastic material

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Shield volcanoes
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Shield volcanoes

• low and wide
• Built by many layers of runny lava flows
• Shield volcanoes form at hot spots.
• The Hawaiian islands are an example.

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Shield volcano

• A Shield volcano a Basaltic
  lava flow

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Composite Volcanoes
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Composite volcanoes

• A.k.a. strato-volcanoes
• very tall with steep sides sometimes rising
  10,000 feet high
• Made of alternating layers of lava flows,
  volcanic ash, cinders, blocks, and bombs.

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• a composite volcano a
  lava flow

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