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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.
North America is the third largest continent on Earth, bounded by the Arctic Ocean to the north, the Atlantic Ocean to the east, the Pacific Ocean to the west and the Caribbean Sea to the south. The narrow Isthmus of Panama connects North and South America. Australia is the smallest continent in the world.