E. Barnes, Professional Gamer, Professional Gamer, Washington
Answered Jun 13, 2019
The correct answer to this question is Panthalassa. It is also known as the Proto-Pacific or Paleo-Pacific, which means old Pacific. This is because the ocean we know today as the Pacific Ocean came from the Panthalassa's Ocean center. The Panthalassa covered 70% of Earth's surface during the Paleozoic-Mesozoic transition. The oceanic plates of Panthalassa were reconstructions of traditional plate tectonics.
Terranes formed from the margins of the ocean. These terranes included the Kolyma-Omolon and the Stikinia. Marginal seas and oceanic plates were also created, which include Oimyakon, Slide Mountain Ocean, and Mongol-Okhotsk. The ocean floor of the Panthalassa disappeared due to subduction of continental marginals.