The higher res shows a bit better what's going on.
What happens if you apply a bit of displacement the way I did it for you in the grand canyon .tgd I gave you?
The scale and amplitude of the displacement might need to be adjusted, but it could give interesting results.
Right now the displacement on the surface is a bit too noisy and strong.
(For better evaluation during design/development you might consider temporary disabling of the strata shader)