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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.
An ocean is a large area of salt water between continents. Oceans are very big and they join smaller seas together. Together, the oceans are like one ocean, because all the oceans are joined. Oceans (or marine biomes) cover 72% of our planet. The largest ocean is the Pacific Ocean.