Block Selection

This section to define the selection criteria for selecting blocks from the block model.

Note: When creating a new specification file (.res_spec), the block selection mode will be set to Proportional cell evaluation.

Block selection

Either all blocks or specific blocks can be selected. If you select Select specific blocks by, then you must enter one or more of the following selection criteria:

Variable

Select this check box to restrict the blocks by a block model variable. You will need to specify the variable, as well as a particular value.

Example: To restrict blocks to those where Material equals Ore, select 'Material' as the variable (from the drop-down list) and enter 'Ore' as the value. However, if you require all blocks thatdo nothave this specified value, then enable the Reverse matching check box. The block model variable may be numeric (for example, the grade variable 'Au') or character (for example, 'Geology') variables.

Condition

Select this check box to use a further constraint upon a numeric block model variable, for example, Fe GT 10.0 (iron value greater than 10.0). The maximum size of the condition is 132 alphanumeric characters. A list of available operators/functions to use when defining this condition is provided in Appendix B .

Bounding triangulation

Select this check box to restrict the blocks by a triangulation. This is useful when, for example, you want to evaluate reserves in a particular solid triangulation such as a stope.

Section thickness

Select this check box to restrict the blocks by a projection plane. You will need to enter its associated thickness. The blocks that are in this thickness will be selected.

The section plane can be selected by line, points or grid coordinates. This information is entered through the Projection Plane panel, which displays by clicking Define Section. You may also select the Use block centroids check box and use it with this restriction.

Use bounding surfaces

Select this check box to restrict the blocks by bounding surfaces. If you select this option, you must select the Upper triangulation and Lower triangulation from the drop-down list, or click Browse to select a triangulation from a location other than your working directory. Only blocks that lie in the overlapping sections, as viewed in plan view, of the surfaces are selected.

Use bounding box

Select this check box to restrict the blocks by a box. If you select this option, you must enter the minimum and maximum coordinates for X, Y, and Z in the block model coordinates (X. Y, Z CENTRE). If the block model origin is set at 0,0,0, then real world coordinates should be entered in the x y z minimum and maximum coordinates. If the block model origin is set at real world coordinates, then enter coordinates for the bounding box that are offset a certain distance from the origin. The distance of offset will be determined by the dimensions of your bounding box. It will be the distance to the minimum and the distance to the maximum X, Y and Z from the origin of the block model.

Figure 1 : Cut and Fill Surfaces Selection panel

Model names

Older surface

Enter, or select from the drop-down list, the name of the old triangulation surface. Click Browse to select a file from another location.

Newer surface

Enter, or select from the drop-down list, the name of the newest triangulation surface. Click Browse to select a file from another location.

Material codes

Material code for cut / Material code for fill

Enter the material codes for the fill and cut.

Management of fill reserve

This section to define the conditions when calculating the tonnage and grades for the fill.

Use block-model density values to calculate fill tonnage

Select this option to use the density values from the chosen block model.

Use default density value of

Select this option to use a specific density value.

Use block-model grade values for fill material

Select this option to use the grades values from the chosen block model when calculating the grade values for the fill material.

Do not report grade values for fill material

Select this option if you don't want to calculate, or report on, the grade values for the fill material.

Click OK.

Use block centroids

Select this option to include a block if the block's centroid is in the region. Note the entire block is included.

Proportional cell evaluation

Select this option to include those blocks that touch the region. When selecting blocks, all blocks that touch the region are selected.

Note: The bounding triangulation nominated through the Block Selection panel is ignored if any triangulation regions are specified.
Using a combination of block selection method produces approximate intersection volumes.