Can't read everything, but (EARTH SPOILERS):
At the end of season 3 we see Earth2, which is where the show ends.
In Sometimes a Great Notion we see Earth1, the home of the 13th tribe. The producers were very smart in the the episode before. We saw green and blue for oceans and continents, but we saw landmasses we only assumed are our continents. When you look again they're very generic looking.