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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.
Asia is the world's largest continent and is bordered to the west by Europe, the Mediterranean Sea, the Black Sea and the Caspian Sea. Asia is bordered by the Pacific Ocean to the east. The Arctic Ocean and various other seas meet the northern border of Asia.