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10 Cards in this Set
- Front
- Back
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What is the time period between the pole reversals?
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220,000 years
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Where are the oldest rocks?
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In deep ocean trenches
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What are the youngest rocks called?
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pillow rocks
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How long does it take to renew the SF?
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220,000 years
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Where is true north?
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Hudson Bay
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What are pillow rocks made from?
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magma from the mantle
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What does seafloor spreading cause?
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continental drift
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What does sonar do?
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help map the seafloor
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Who is Harry Hess?
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an american geologist
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What is the mid ocean ridge?
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the longest chain of mountains in the world
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