Tethys Ocean

The Tethys Ocean was an ocean that existed between the continents of Gondwana and Laurasia before the opening of the Atlantic Ocean. Its remnants today are the Black, Aral, and Caspian Seas. It was first proposed by the Austrian geologist Eduard Suess in 1893, and was named for the sea goddess Tethys.

Forming some 300 million years ago with the breakup of Pangaea, Tethys was at first a western extension of the otherwise world-spanning ocean of the time. It grew, shrank, and moved through a variety of different incarnations until about 50 million years ago, when the gradually widening Atlantic Ocean and closing gap between Africa and Europe squeezed it out of existence. Many of the rocks in the Alps were once on the Tethyian sea floor, as evidenced by the many marine fossils found there. During most of these 250 million years it was a relatively shallow interior sea, open at both ends, which divided the northern and southern continents. During the last 20 million years or so, after Central Asia and India closed off its eastern end, it is sometimes called the Tethys Sea or Tethys Seaway.

The Tethys Ocean is of considerable importance to paleontologists, as for very long periods much of the world's sea shelves were found around its margins. Marine, marsh-dwelling, and estuarian fossils from these shelves are of considerable importance.