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Published byGrant Robertson Modified over 9 years ago
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Volcanic Activity: What causes a volcano?
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What is a volcano? The hot upper mantle part of the lithosphere escaping through the crust part of the lithosphere.
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Where are volcanoes? Subduction zones: Where one plate is pushed under another plate.
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Where are volcanoes? Subduction zones: Where one plate is pushed under another plate. Divergent zones: two plates pulling apart and creating ridges.
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Where are volcanoes? Subduction zones: Where one plate is pushed under another plate. Divergent zones: two plates pulling apart and creating ridges. Hot spots: These can happen anywhere on the planet that the crust is weak and thin (even in the middle of a plate).
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Volcano vocabulary: Magma: Melted mantle beneath the surface of the Earth.
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Volcano vocabulary: Magma: Melted mantle beneath the surface of the Earth. Lava: Magma that reaches the surface and is exposed to the atmosphere.
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Volcano vocabulary: Magma: Melted mantle beneath the surface of the Earth. Lava: Magma that reaches the surface and is exposed to the atmosphere. Vent: The path gas and magma use to escape the crust.
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Types of eruptions: Explosive: Happen when magma gets very thick from high Silica content and contains deadly gases.
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Types of eruptions: Explosive: Happen when magma gets very thick from high Silica content and contains deadly gases. – Pyroclastic flow: A mixture of hot gases (up to 800 degrees Celsius), ash, cinder, and bombs hurled from a volcano at speeds up to 200 km per hour.
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Types of eruptions: Explosive: Happen when magma gets very thick from high Silica content and contains deadly gases. – Pyroclastic flow: A mixture of hot gases (up to 800 degrees Celsius), ash, cinder, and bombs hurled from a volcano at speeds up to 200 km per hour. Effusive: Dominated by lava flowing from the volcano onto the ground.
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Types of volcanoes: Composite Volcanoes
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Types of volcanoes: Composite Volcanoes Shield Volcanoes
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Types of volcanoes: Composite Volcanoes Shield Volcanoes Cinder Cones
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Types of volcanoes: Composite Volcanoes Shield Volcanoes Cinder Cones Spatter Cones
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Types of volcanoes: Composite Volcanoes Shield Volcanoes Cinder Cones Spatter Cones Complex Volcanoes
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