Plate tectonics

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Plate tectonics and Sea floor spreading
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Plate tectonics ??????????????????????????????????
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Sea floor spreading ??????????????????????????
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Asthenosphere
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???????????????????????????? Asthenosphere
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Plate boundaries
1. Divergent boundaries -- where new crust is
generated as the plates pull away from each
other.
2. Convergent boundaries -- where crust is
destroyed as one plate dives under another.
3. Transform boundaries -- where crust is neither
produced nor destroyed as the plates slide
horizontally past each other.
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Divergent boundary
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Convergent boundaries
1. Oceanic-Oceanic convergence 2.
Oceanic-Continental convergence 3.
Continental-Continental convergence
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Oceanic-oceanic convergence
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Oceanic-continental Convergence
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Continental-continental convergence
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oceanic-oceanic
oceanic-continental
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continental-continental
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Transform boundaries
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Hot spots
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Hot spots