QUESTION: I use thin_fence to generate cross section through geological volumes and would like to also show my fault surfaces on the same section. To create the geology part of the section I connect load_evs_field (containing the geology volume) to thin_fence. The cross-section line is determined through draw_lines and then also connected to thin_fence. By also connecting draw_lines to post_samples (which contains my wells) I can also project the wells onto this finished cross section.

This all works great but what I’m wondering is if there is a way to also project my fault surfaces onto the same section? Thin_fence doesn’t support surfaces so is there another way I could do this?

You are correct that thin_fence requires a volume to create its output, but the extrude module will extrude in any direction, so you can use it to turn your fault surfaces into very thin volumes, which thin_fence can work with.

There is no limit to how thin the volume can be, it just needs to be a volume vs. a surface.  The only thing you must avoid is extruding parallel to the surface or extruding a complex surface “through itself”.  There are some shapes for which this concept will not work, such as a “C” shaped surface, but that is also an unlikely fault surface.

If you want that output to be displayed as lines, you can still pass this small surface through external_edges to get lines.