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It's not always easy to see the Earth's crust.

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It is covered by vegetation and oceans.

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But if you could drain the Earth's oceans and strip away our planet's vegetation,

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the Earth might look something like this.

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Now we can see the Earth's hard outer shell.

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And if you look closely, you can also see where the shell is cracked.

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The red glowing lines mark the places where the Earth's shell is cracked

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into small and large pieces called tectonic plates each plate carries a continent or an ocean basin

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or sometimes both the plates are moving one to two inches a year in different directions

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carrying continents and ocean basins with them millions of years ago the earth looked something

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like this every continent in a different position they were so close together they

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formed a single supercontinent called Pangea. But even then, the continents were moving

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a few inches a year and kept moving until they reached their present day positions.

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The theory that continents move is called continental drift. When you look at a globe

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today, you are looking at only a moment in time because the continents are still moving

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inches a year too slow to see as they move farther and farther apart then the continents

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will stop moving apart they will change directions coming together once again millions of years

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from now scientists expect the world to look entirely different every continent in a new

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position carried there by the moving plates while we can't see this movement occurring

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we can see the effects.