New answers tagged model
It all depends what data you have, if you just need to grid a surface gis is ok, if you need to interpret the subsurface you need special software...
You don't need a specific add-on programme, look at The Subsurface Geology of Brussels, Belgium, Is Modeled with 3D GIS with 3D Analyst. or Modeling the Terrain Below (3D Borehole tools)
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