Panthalassa

Prehistoric superocean that surrounded Pangaea

In historical geology, Panthalassa, also known as the Panthalassic Ocean or Panthalassan Ocean (from Ancient Greek πᾶν (pan) 'all' and θάλασσα (thalassa) 'sea'), was the vast superocean that encompassed planet Earth and surrounded the supercontinent Pangaea, the latest in a series of supercontinents in the history of Earth. During the Paleozoic–Mesozoic transition (c. 250 Ma), the ocean occupied almost 70% of Earth's surface, with the supercontinent Pangaea taking up the remainder.

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