September 23, 2012 Volcanoes! What is a volcano? A volcano is a land or underwater feature that forms when magma reaches the surface of the earth.
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September 23, 2012
Volcanoes!
What is a volcano?A volcano is a land or underwater feature that forms when magma reaches the surface of the earth.
September 23, 2012
Magma: Molten, liquid rock found underground
Lava: Molten, liquid rock found on Earth's surface
Overlapping of plate boundaries Clip
September 23, 2012
How do volcanoes form?The heat inside Earth is left over from when the planet first formed. It tries to escape through plate boundaries.
Magma Floats Clip
Magma rises up to the surface because it is less dense (lighter) than the rocks around it.
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Where do volcanoes occur?
1. Divergent Boundaries
2. Convergent Boundaries
3. Hot spots
Map of Active Volcanoes on Earth
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1. Divergent BoundariesThere are volcanoes at mid-ocean ridges!
Divergent boundaries Clip
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2. Convergent BoundariesVolcanoes also happen where plates are subducted!
Convergent Boundary Clip
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3. Hot SpotsVolcanoes occur away from plate boundaries at hot spots like Hawaii!
Hawaii hot spots Clips
September 23, 2012
Brain pop!
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