Conventional polygonal and block modelling techniques inadequately
represent the grade-thickness distribution of some narrow shear and
stratabound gold deposits. The polygonal influence of high-grade drill
intercepts can result in overestimates of resource tonnages at high-grade
cut-offs. Although block modelling methods provide grade smoothing
and a better representation of structural continuity, the technique can lack
precise definition of ore width. An alternative method known as Spatial Object Modelling (SOM) has
been developed on MineMap software to overcome some of these
modelling issues. This method does not rely on a uniform cell size and
allows grade smoothing between resource intercepts in three-dimensional
space. The SOM technique creates grade-thickness bars on regular,
user-defined spacings which allow easy visual comparison of raw
intercept data to the interpolated model. Model cell values are readily
transformed into isopachs, isopleths and resource perimeters for reporting
and mine planning purposes.