Thanks! My own devising, but really based on existing techniques. Although of course it will be "published" since source is going out. Its actually based on just two things - one is the same heightmap used for the world, transformed and overlayed several times to produce unique cracks (it reads this based on the world position, and then does a whole bunch of sin calculations and stuff to make it look random). The same map is used to add in sediment and grass, just more permutations on the calculations. The other is voronoi patterns. It combines these to form what turned out to be surprisingly unique and cool looking (even I was surprised how it turned out).