Converting historical 2D plans into Surpac 3DM solids


In many projects, mining technical teams need to interpret 2D plan data to create useable 3D solids that accurately represent the interpretation of the old workings. These 3D solids are required for resource model depletion, mining design and safety management purposes.

This example describes the process for extrapolating drive pick-up strings in the absence of enough drive survey, to enable a triangulation that accurately depicts the drive profile.

The interpreted strings here represent the floor perimeter strings and have been set to the correct Elevation, and are used to make a valid 3D solid. A similar process could be used if only a shoulder or rib strings (at set height above floor of say 1.5m) were available.

Note that the method will not give as accurate a volume as having a completed suite of floor, rib, shoulder and back strings to be triangulated, but the purposes of depleting the block model may be of sufficient accuracy.


1. Open up the string file in Surpac.



2. Edit out any cross-overs of drives as seen in the image above. If they are drives going under-over workings, make sure that this is reflected in the RL of the strings.




3. Solids > extrude and triangulate a string range




Forward in this case means up. So the string would be lifted 4m vertically up to create the solid.

It’s important that you tick the box, increment object ID. Work out what the height of the drives needs to be and put this in the z offset. Then apply.

The Solids are created.




4. Save the dtm and then validate.

5. You can now use this to calculate volumes of the development





Or use the solids to run Block Model reports





Or use the solid to flag the model with the area that has been mined.





Then display with blocks mined = 1






Kim Ferguson-Thomas

Kim Ferguson-Thomas

Technical Customer Support Consultant, GEOVIA at Dassault Systèmes
Kim Ferguson-Thomas has more than 20 years’ experience as a geologist in the mining industry, working in exploration, underground and open-cut mines within Australia.