Historical Theory
In 1893, using fossil records from the Alps and Africa, Eduard Suess proposed the theory that an inland sea had once existed between Laurasia and the continents which formed Gondwana II. In this moment of Earth's life, however, these two continental masses were united in a unique supercontinent, known as Gondwana III or Pangaea. He named it the 'Tethys Sea' after the Greek sea goddess Tethys. When the theory of plate tectonics became established in the 1960s it became clear Suess's "sea" had in fact been an ocean. Plate tectonics also provided the mechanism by which the former ocean disappeared. In plate tectonic theory oceanic crust can subduct under continental crust.
Read more about this topic: Tethys Ocean
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