Working with 3d DXF, how can I export both top and bottom as individual surfaces or points

[Daniel_Ripley]

Hello,
I have been provided with 3d rock strata layers that have been created using Maptek Vulcan software.
The layers were provided as 3d DXFs and contain a 3d object file.
I wish to be able to split the top surface from the bottom surface so that I have two separate surfaces.
I am open to exporting the files as a point cloud/vector data or as another 3d DXF

Can anyone help me out?

[daniel]

Not sure to understand the problem. Have you already managed to load the 3d DXF file? Can you maybe show us what the mesh looks like?