Proving the Theory of Plate Tectonics

So far you have seen how we can use the distribution of earthquakes, volcanoes and fold mountains to mark the position of plate boundaries. However this is not enough to prove the theory of Plate Tectonics.


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Alfred Wegnerwas the first person to suggest the theory of continental drift in 1912, although Abraham Ortelius had suggested that continents could have moved in 1596. It took until the 1950's for Wegner's ideas to be accepted by the scientific community.

In this lesson you are going to try to prove the theory. the advantage you have is that today there is a lot more evidence than in Wegner's day.


Pangea


Before we go any further, it is important to mention Pangaea. By proving that Pangea existed between 300 and 200 million years ago, you have taken a big step towards proving the theory of Plate Tectonics.


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The Evidence


1) The fit of the continents


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First known illustration of the Opening of the Atlantic Ocean, by Antonio Snider-Pellegrini, 1858.





2) Fossil Evidence


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3) The presence of the Mid Atlantic Ridge


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Scuba diving on the mid Atlantic ridge in Iceland. North America on the left, Europe on the right.




4) The relative age of Oceanic crust

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5) Palaeomagnetism


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6) Hot Spot Volcanoes: Hawaii and the Emperor Sea Mounts


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7) Constructive and Destructive Plate Boundaries


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