By Lisa Swinnard
There is more than one way to create a boundary surrounding a cut-off grade in Leapfrog; however the different techniques used to create these boundaries rely on different underlying concepts. Which tool to select will depend on the ultimate purpose for building the boundaries.
The typical way to create these boundaries is by building grade shells using the Interpolant tool in Leapfrog. Interpolated grade shells are built by using the known drillhole or point data to interpolate values infinitely across the boundary extents; isosurfaces (grade shells) are then created to link up identical values. Grade shells created by interpolation represent a “soft boundary”, as it is not possible to snap these isosurfaces (grade shells) to contact points on drillholes. Grade shells created using interpolation are ideal tools for exploration drillhole targeting.