This is a list of formeroceans that disappeared due totectonic movements and other geographical and climatic changes. In alphabetic order:

• Bridge River Ocean, the ocean between the ancientInsular Islands (that is,Stikinia) andNorth America
• Cache Creek Ocean, a Paleozoic ocean between theWrangellia Superterrane andYukon-Tanana Terrane
• Iapetus Ocean, theSouthern Hemisphere ocean betweenBaltica andAvalonia
• Kahiltna-Nutotzin Ocean,Mesozoic
• Khanty Ocean, thePrecambrian toSilurian ocean betweenBaltica and theSiberian continent
• Medicine Hat Ocean, a smallProterozoic ocean basin
• Meliata Ocean, a smallback-arc basin in theMesozoic to the east ofAdria
• Mezcalera Ocean, the ocean between theGuerrero Terrane andLaurentia
• Mirovia, the ocean that surrounded theRodiniasupercontinent
• Mongol-Okhotsk Ocean, the early Mesozoic ocean between theNorth China andSiberia cratons
• Oimyakon Ocean, the northernmost part of the MesozoicPanthalassa Ocean
• Paleo-Tethys Ocean, the ocean betweenGondwana and theHunicterranes
• Pan-African Ocean, the ocean that surrounded thePannotia supercontinent
• Panthalassa, the vast world ocean that surrounded thePangaea supercontinent, also referred to as thePaleo-Pacific Ocean
• Pharusian Ocean,Neoproterozoic
• Poseidon Ocean,Mesoproterozoic
• Pontus Ocean, the western part of the early MesozoicPanthalassa Ocean
• Proto-Tethys Ocean,Neoproterozoic
• Rheic Ocean, the Paleozoic ocean betweenGondwana andLaurussia
• Slide Mountain Ocean, the Mesozoic ocean between the ancientIntermontane Islands (that is,Wrangellia) andNorth America
• South Anuyi Ocean, Mesozoic ocean related to the formation of theArctic Ocean
• Tethys Ocean, the ocean between the ancient continents ofGondwana andLaurasia
• Thalassa Ocean, the eastern part of the early MesozoicPanthalassa Ocean
• Ural Ocean, the Paleozoic ocean between Siberia andBaltica

• Category:Historical oceans
• List of oceans – Limits of Earth's oceanic watersPages displaying short descriptions of redirect targets
• Paleocontinent – Major landmass in the geological past
• Paratethys – Prehistoric shallow inland sea in Eurasia
• Piemont-Liguria Ocean – Former piece of oceanic crust that is seen as part of the Tethys Ocean
• Superocean – Ocean that surrounds a supercontinent, an ocean that surrounds a globalsupercontinent
• Valais Ocean – Subducted ocean basin. Remnants found in the Alps in the North Penninic nappes.

• Oceans
• Oceanography
• Historical oceans
• Mesozoic paleogeography
• Paleozoic paleogeography
• Proterozoic paleogeography

• Articles with short description
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