Earth maps are mods or scenarios you loads from Advanced>Load a Mod.... or Custom Scenario.
The map is an 18 civilisation map of the earth (funnily enough!!!

)
Fractal makes the landmasses go all pear-shaped.... in a good way, making them very random.
Personally, I prefer Big and Small map script for general play as it emulates a world like map with continents, islands, archipelagos.... I've had some really fantastic maps from this script.