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Panthalassa, also known as the Panthalassic or Panthalassan Ocean, (from Greek Ïá¾¶Î½ all and Î¸Î¬Î»Î±ÏÏÎ± sea), was the superocean that surrounded the supercontinent Pangaea. During the PaleozoicâMesozoic transition c. 250 Ma it occupied almost 70% of Earth's surface.
It is the most populated continent and the birthplace of many ancient civilizations. On the north of Asia lies the Arctic Ocean, on the east and south it is bounded by the Pacific and the Indian Ocean respectively. But on the western side, it merges with Europe and together they are called Eurasia.Modern geographers consider Ural Mountains, Ural River, part of Caspian Sea and the Caucasus Mountain as boundaries between Europe and Asia. The highest (Mount.ut on the western side, it merges with Europe and together they are called Eurasia. Modern geographers consider Ural Mountains, Ural River, part of Caspian Sea and the Caucasus Mountain as boundaries between Europe and Asia. The highest (Mount.