Hi,

first I used Houdini Apprentice to generate the displaced noise mesh on a planar surface.
Then I brought the mesh into ZBrush for a bit smoothing. After that I generated a normal
map from the mesh and used it in Knald to generate a height map. Once you have a height
map you can then simply use the free program Zsurf to generate the NURBS surface. In MoI
I extruded the edges and once I had the sides I trimmed them and added a planar surface
to obtain a solid. The lines you see in the solid are from trimming, so that one can use
the separated surfaces for colorizing.

Regards
Stefan