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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.
The part of the continent located under the water. On the bottom of the ocean, there is a central ridge, or mountain range, that divides the ocean floor into two parts. In the center of the highest part of the mid-ocean ridge is a narrow trench.