One thing I think we're forgetting is strata redirects colour as well.
This is a simple colour surface powered by a single PF setup (modulated with colour nodes) stretched on X and Z, all the warping is done by the strata which really beautifies the texturing imo.
Any way you can get the Strata and Outcrops shader to produce something other than unnatural looking stair steps and all-too-horizontal layers, that's progress! It also appears you have some Voronoi-related fractures thrown in for extra realism. Nice work!
Yeah it's a simple two PF disp on lateral, voronoi ridges and billows with 4 strata applied to one more PF that crates sedimentary lines.