Started out with a simple image map with some patches of white-grey-black (could have been procedural, but I quickly wanted a particulare flow/shape), displaced it, added a slope by displaced distance shader and set Daniil's plugin to work. I didn't use the actual erosion, just the maps. Actually just playing around a bit, so I added some partly procedural far city, and some other stuff. Man encroaching on nature, so to speak.