Underground Mine Reserves

This command calculates quantities and qualities from drillholes or predefined grid or block models. Key strata are intended to be the target ore, and non-key strata are intended to be the overburden, interburden and parting strata. Within the drillholes or Geologic Model file, each strata has a field that specifies whether the strata is key or non-key.  There are many options for reserve calculation and they are detailed in order of appearance below.

• Modeling Method: The reserves can be generated on-the-fly from the selected drillholes or read from stored grid files put into a Geologic Model file. The on-the-fly modeling method can be either Triangulation, Inverse Distance, Kriging, Polynomial or Linear Least Squares. An explanation of these different methods is found under Make Strata Grid Files. The stored grid file method is the Geologic Model option. The Geologic Model method uses prepared grid files that represent the bottom elevation or thickness and quality attributes (i.e. BTU) of the strata. The grid files associated with each strata and the ground surface are set in the Define Geologic Model command under Drillhole.
• Use Triangulation Subdivision:  This option only applies to the modeling methods of Triangulation and Polynomial. It subdivides the triangles to create smoother surfaces and ensure that contours do not cross.
• Use Global Trend Extrapolation: This also applies only to Triangulation and Polynomial. This option finds the average slope and direction of the existing data and applies this slope to extrapolating where there is not surface data. .
• Make Thickness Grids: Turning this option on will create thickness grids of the selected or all strata. It will prompt to create an overburden thickness grid, a key thickness grid and a key tons grid (tons/sq ft. or m).
• Output Grids for Each Strata: Turning this option on will create grid files for the bottom of each strata found in the drillholes. Each grid needs to be named separately. The command Make Strata Grids is a better way to create these grids.
• Report Areas On One Row: This option puts all the strata quantities and qualities for each inclusion polyline on one row. This format is best suited for only a few strata and for printing landscape on a page. If it is not selected, then each strata will appear on a separate row.
• Use Property Boundaries: Property boundaries can be used to break up the reserve by owner and property. The commands for laying out property boundaries are in the Boundary menu. Essentially, property boundaries are closed polylines with owner and property ID names. The property polylines do not need to be clipped with the calculation inclusion perimeter or pit polylines. The program will internally clip the properties with the calculation areas and report the amounts by property within each pit area. If a pit or inclusion polyline is not covered by a property, the property name used for these quantities is "unknown". To activate property boundaries, click on the Use Property Boundaries toggle and the program will search and find them automatically.
• Calculate Strata Qualities: This toggle will report the average qualities for strata attributes such as BTU and sulfur. Otherwise the program skips calculating qualities to save time. Besides reporting the qualities for each strata individually, the program can also report the total averaged qualities. By default, the qualities are weight averaged by tons which are calculated by using the strata volume and density.
• Recovery Percent: This window defines the percentage of Key strata volume that was recovered in mining and to include in the volume and strip ratio reporting. The non-recovered key strata is added to the NonKey volume. The recovery percent in the Reserves dialog applies to all the Key strata. Enter in as 100 or 95.4 or 92, etc. 
• Use Strata Definitions (for Recovery): To have different recoveries for each Key strata, use Define Strata to create a strata definition for each Key strata with the appropriate recovery percent. Then run Surface Mine Reserves and click on Use Strata Definitions.
• Use Attribute (for Recovery): Another recovery method is to have a strata attribute for recovery. This allows for different recovery percents at different drillholes. Then the recovery is modeled for the area. The name of the recovery attribute is specified in the dialog. This attribute will need to appear in the drillholes for modeling on the fly, or in the Geologic Model as a strata attribute, with the name spelled as it appears in the Name window to the right.
• Name (Attribute): This is the name of the recovery attribute that will be referenced when using the Use Attribute option for recovery percentage.
• Min Key Thickness To Use:  This option adds key strata to the nonkey strata above, in areas that have thickness less than the specified minimum thickness. Also areas with thickness less than the minimum are not counted in the reported strata area. 
• Min Minable Parting Thickness: This setting will add the non-key parting quantities with the key quantities when the non-key parting  thickness is less than the specified amount. For example, if the Min Minable Parting is set to 0.5, then a non-key strata between two key strata would be combined with the key in areas where the non-key thickness is less than 0.5 feet. In areas where the thickness is greater than 0.5, the non-key quantities are not adjusted. Combining the non-key quantities to the key will add to the total key tons and affect the strip ratio. If the non-key strata has qualities (i.e. ASH, Sulfur), then these non-key qualities will be composited by nonkey tons with the key tons for the portion of non-key that is less than the minimum parting. This will dilute the key qualities.
• Non-Key Thickness To Add To Key: Above Key/Below Key: These fields allow you to specify the amount of non-key thickness above and/or below the key strata that will be combined with the key (roof and floor dilution) This amount will be taken from the non-key quantities and added to the key. Similar to the Min Minable Parting Thickness, the non-key quantities will increase the total key tons which affects the strip ratio and key volume mined. Also any non-key strata qualities will be combined by thickness, weighted by NonKey density, and added to the key which dilutes the key qualities. For example, if you estimate that 0.25 feet on average of the overburden is taken with the coal, then you could set the Non-Key to Add to Key for Above to 0.25.
• Which Strata To Include...: This determines what will be calculated for the reserve. If All is chosen, then all strata in the drillholes or Geologic Model file will be calculated and reported. If Selected is chosen, then the next window to appear is where one or multiple strata can be selected. This can be used for multiple reserve runs, selecting different strata to represent each bench.
• Use Named Pit Areas: The area for calculating quantities defaults to the limits of the selected surface entities and drillholes if no inclusion perimeters are selected. To control the calculation area, multiple closed polylines for areas to include and/or exclude can be selected. An unnamed pit polyline will limit the area of calculations. Also, areas can be labeled with site and pit names (i.e. Site 1, Pits 101, 102, ...). Surface Mine Reserves will then calculate the strip ratios and volumes for each site and pit area. To use site and pit names, there are several commands for creating named pit polylines in the Boundary menu of Underground Mining. If this is selected, then it will look just for named pit polylines, ignoring anything else. The Specify Names button will name the polylines from inside this command if they are not already named using commands found under Boundary.

The Report Formatter Options dialog is the final step of the Underground Reserves routine. It is documented elsewhere in the manual for more details on its operation.

Prompts

Underground Mine Reserves dialog
Select surface entities and at least 3 drillholes. (Unless using a Geologic Model.)
Select objects: select the drillhole symbols and surface entities Surface entities can include points, lines, and polylines.
Select the Inclusion perimeter polylines and ENTER for none:
Select objects: select the polylines or named pit polylines The area within these polylines will be included in the calculations. They must be closed polylines.
Select the Exclusion perimeter polylines and ENTER for none:
Select objects: select the polylines The area within these polylines will be excluded from the calculations. They must be closed polylines.
Make Grid File Set grid resolution
Triangulating points ... 49
Pass> 6 NULL Z values left> 0
Processing cell 2500 ...
Finished strata Y2
The above four steps are repeated for each strata.
Report Formatter

Pulldown Menu Location: StrataCalc in Advanced Mining
Keyboard Command: reserves