Strip Ratios

Use Strip Ratios to calculate a ratio from a Stratigraphic Block model or HARP model. The stripping ratio is defined as the volume of waste material divided by the tonnage of product material.


The Product and Waste options need to be populated with precalculated block model variables that contain the tonnes of product and the volume of waste. The stripping ratio is then calculated based on the Waste divided by the Product.

Required inputs are:

  • A HARP model which has been created with product horizons and limited to a topography or other limiting surface
  • A global horizon list file (.gdc_glob)

Strip ratios can be written to block model variables. Two types of stripping ratios may be stored: cumulative or incremental.

The underlying methodology closely mirrors that of similar grid-based functionality found in Grid Calc > Composite Models > Create Ratio and Burden Grids. As Grid Calc > Integrated Stratigraphic Modelling > Strip Ratios utilises a HARP model instead of grid models, input ratios can be calculated on structurally complex stratigraphic models. This allows for calculations in deposits that include normal and reverse faulting.

Note:   Grid Calc > Integrated Stratigraphic Modelling > Strip Ratios can be run from a T-Shell window. Enter the following command at the prompt:

bratio <full specification file name> <input block model name>

The Stripe Ratios panel has four branches: