Lesson Summary

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  • Abraham Ortelius first suggested that the Earth might have consisted of a supercontinent.
  • Alfred Wegener was the first to present it as a scientific theory in 1912. He called the continent Pangaea.
  • Pangaea is theorized to have split up about 200 million years ago.
  • Wegener was unable to account for the force necessary to split up a supercontinent. Scientists of that time rejected his theory.
  • Harry Hess suggested that the seafloor was spreading as a result of magma bubbling to the surface from the Earth's core.
  • The theory of a supercontinent and the evidence of the seafloor spreading combined together is called "plate tectonics."
  • Some of the evidence for plate tectonics includes magnetic patterns on the sea floor, fossil records and the relationship between volcanoes and plates.
Last modified: Saturday, 1 May 2010, 2:11 PM