africa afro-eurasia americas antarctica arctica asia asiamerica atlantica atlantis avalonia baltica canada congo craton continent craton earth euramerica eurasia europe geochronology geology gneiss gondwana kaapvaal craton kalahari craton kazakhstania kenorland kerguelen plateau laurasia laurentia list of supercontinents meropis mythological places oceania paleomagnetism pangaea pangaea ultima pannotia pilbara craton radiometric dating rodinia south africa supercontinent superior craton terra australis western australia