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Breaking up is hard to do.
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Sometimes, it feels like it goes on forever...days...weeks...months...millions of years?
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Just ask Pangaea.
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Plate tectonics.
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It's not your fault if you take it for granted.
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The concept that the Earth's crust moves around, rubs together, and pulls apart seems obvious now.
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I mean just look at it.
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But as recently as 50 years ago, thinking the continents had ever actually moved from their current locations would have gotten you laughed out of any serious scientific meeting.
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The notion of moving continents all started with Alfred Wegener.
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He noticed the continents appeared to fit together, almost perfectly, like a jigsaw puzzle.
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And if they used to fit together, that means they must have somehow moved apart.
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This led him to introduce a new idea: continental drift.
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The snug fit of coastlines wasn't the only evidence that the continents were all once joined together in a giant landmass, all nice and cozy.
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Wegener noticed fossils of certain animals had been found in Antarctica, India, and Africa.
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How did the same animal end up all over the world?
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Before, geologists thought land bridges had connected the continents, and were now submerged or eroded away.
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Or else, they swam.
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Remains of an ancient fern had also been found on five continents.
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And ferns definitely can't swim.
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It just didn't make sense.
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That wasn't all.
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The same types of rocks and mountains lined up continuously between continents.
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It was a convincing body of evidence suggesting the continents moved around during Earth's history.
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So obviously Wegener was celebrated and awarded for this brilliant idea, right?
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More like the opposite.
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One paleontologist called his theory "Germanic pseudoscience".
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He was ridiculed around the world for his "delirious ravings."
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The reason for all the hate was no one could see how continents might move.
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Did the rotation of the Earth create enough centrifugal force to move them?
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Was it the tides?
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These forces weren't strong enough to move entire continents.
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Wegener was never able to convince other scientists before he died on an expedition to Greenland in 1930 at only 50 years old.
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He never knew the fate of his ideas.
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In 1929, Arthur Holmes showed thermal convection in the mantle could create enough of a current to move the continental crust on top of it, an idea he originally got from Wegener.
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In 1962, geologist Harry Hess found a strange magnetic pattern along a seafloor ridge.
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Earth's magnetic field has flipped hundreds of time over the planet's history.
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Magnetic minerals deep in the Earth, in hot magma, preserved this magnetic fingerprint as they cooled and hardened into rock.
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Just like planetary tree rings, geologists could analyze the rock on either side of the ridge to retrace its history.
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The seafloor was spreading apart at these ridges, where new rock was oozing up from the hot mantle.
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Geologists finally had proof that earth's crust wasn't static.
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It was constantly changing.
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They're even moving right now.
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Can't you tell?
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Probably not.
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Every year, the spreading at the Mid-Atlantic ridge pushes the Eurasian plate and North American plate just 2.5 centimeters farther apart.
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But over millions of years, that really adds up.
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Spreading between plates also happens on land.
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The African plate and the Arabian plate are actually splitting the continent in two.
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These deep rift valleys will eventually become an ocean and create a new separate African landmass.
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The "Ring of Fire" is where denser oceanic crust is moving underneath the less dense continental crust.
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90% of the world's earthquakes and most major volcanoes occur along this margin.
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Monstrous eruptions and destructive earthquakes change our world everyday and influence the lives of humans all over it.
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Just like the surface of our dynamic planet, the story of plate tectonics shows us it can take a little while before earth-shaking ideas change the world.
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If you catch my drift.
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Stay curious!