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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.
Oceans cover 71% of the Earth's surface, and contain 97 percent of the planet's water. The Pacific Ocean is the largest ocean covering an area of 64,186,000 square miles and the Mediterranean Sea is the largest sea with an area of 1,144,800 square miles.In fact even the worldâs smallest ocean Arctic Ocean (5,427,000 square miles) is larger than the Mediterranean.ny water in a sea, ocean or lake that is not close to the bottom or near to the shore can be said to be in the pelagic zone. Areas in the pelagic zone are distinguished by their depth and the ecology of the zone.