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Wondering if it's possible to create a custom mine grid CRS from point data?

I do not know the specific variables for the UTM to mine grid conversion, but I have point data for both projection sets.

Is it possible to create a shapefile of this point data in QGIS and then construct a custom CRS from the equivalent mine grid point coordinates? (Use UTM coordinates to correlate with mine grid coordinates)

PolyGeo
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Rob
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  • One approach might be to create the plan on the earth surface elevation and then decrease the point elevations to drop the required feet below the surface if you know the depth. I believe ESRI had a tutorial on that at one point. – lewis Jul 03 '18 at 23:04
  • Maybe related: https://gis.stackexchange.com/questions/87213/wkt-for-local-mine-grid and https://gis.stackexchange.com/questions/83861/using-customized-coordinate-system-in-arcgis-desktop – AndreJ Jul 05 '18 at 12:47
  • ,,, and https://gis.stackexchange.com/questions/352168/define-custom-crs-in-wkt-from-point-and-angle – AndreJ Feb 27 '20 at 19:26

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I am not sure if mine grid CRSes are exactly correlated to Transverse Mercator projections.

I wrote a Python module to find the similarity transformation parameters that better adapts to a given set of control points in 3-D: https://github.com/gabriel-de-luca/simil.

I use it to transform local surveys to a geocentric CRS, and then I project from geocentric to the desired projected CRS. But you can pass fixed Z values if you want to find 2-D transformation parameters, or a 2-D rotation with a 3-D translation.

I don't create 2-D CRSes transformed from a projected one, I find the transformation parameters and transform my data with ogr2ogr and a PROJ pipeline. But if you want to do it, the WKT2:2019 CRS definition must be a Derived Projected CRS, as defined in section 14.4 of the OGC standarization: http://docs.opengeospatial.org/is/18-010r7/18-010r7.html

Gabriel De Luca
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