Creating geological surface layers from boreholes

So if you have been trying out the borehole tool in the country kits this year you may want to create a surface that uses the subsurface data but follows the existing ground.

Take for example this small amount of boreholes, if I just make a surface from the point group there is minimal information and potentially you could see your subsurface go through the ground.

So this is obviously not going to be too useful

 

 

So a Autodesk colleague of mine Tomas Lendvorsky in Prague came up with a nice method to create a surface which uses the borehole positions and levels but also follow the surface.

In true geology this is not 100% as other factors could happen, but it can be at least your best guess to start with.

 

So using the borehole importer from the toolbox (if you have it installed)

Import your boreholes from CSV, AGS or GEF formats

(These I made up as I don’t think the council would appreciate me bringing an auger on site!)

 

Next make a surface from the borehole top point group

 

Next make a surface from the layer you want, eg from the clay point group

 

Next make a TIN volume surface from the clay surface to the borehole surface (the order has to be correct here)

 

Make a new surface eg ‘Surface from Clay Volume’

Under definition paste in the volume surface you just made

 

Make another TIN volume surface with your ‘Surface from Clay Volume’ and your ground surface (again order is critical)

 

And you are done, check with a quick profile etc

 

Do this a couple of times and using the hatching in the profile view and you can get a good representation

 

Jack Strongitharm

Comments

[Neil Jones]

I do a similar thing except when I create the first volume surface, I run XMLOUT on it, then XMLIN and edit the file to uncheck the volume part then I have a TIN surface for the stratum of interest. As it is not a volume surface all the usual surface tools are available but it obviously is no longer dynamic to changes in the originals

[Patrik]

Hello Jack!
Congratulation to the flower (Rose).
When I use the BH-importer I get the wrong scale for the elevation, my holes becomes 10 times less deep. Also the cogo points get wrong elevation. I have tryed with your example-data and I get the same result. Have you the same problem?

[Jack Strongitharm]

Thanks for your reply.
Back from leave now, so apologies for the delay in getting back to you.

The depth when using the csv method uses cm as a measurement so why the 10x times difference in size potentially

Jack