GGU-3D-SSFLOW: Step 13: Evaluate potentials in section
To define a section, go to "Evaluation/Values in section" or "z/Define section" or use the 
tool in the 3D toolbar. Visualise the influence of the weak spot by tracing the course of the section along the lower system boundary. Press [Return] and go to "Evaluation/Coloured". You will see the potentials in the defined section with the easily visible weak spot (see also "Ex. step 09 Potentials in section.f3d" file):
