Computing Lithology Volumes

RockWorks | Borehole Manager | Lithology | Volumetrics

This program reads an existing lithologic solid model (.RwMod file) and creates a tabular report by computing the total volume or mass for each lithotype as a function of the relative depth/elevation.  The resulting computations are displayed in a row-and-column datasheet.  Lithology solid models are created in the other Lithology menu options.

! This tool requires that you've already created a lithology model (.RwMod file).

Feature Level: RockWorks Standard and higher

Menu Options
Step-by-Step Summary

Menu Options

• Lithology Model:  Click on this prompt to browse for the name of and existing lithology solid model (.RwMod).  The volume calculations will be based on this model.
  
  
• Output Options:  Expand this heading to define what type of results will be included within the report.  You may select multiple options.
• • Nodes:  Check this box to have the program list the number of nodes for each unit within each layer.
  • Volume:  Results will be reported in the cubic units you've defined in your Output Dimensions.
  • Mass:  Computations are based on the Density Factor declared in the current Lithology Table which declare mass per cubic unit. The output will be in the units you've defined in your Output Dimensions.
  • Percent:  Computations represent the percent of material within each layer (or bench).  Note: This number represents percent by volume - not percent by mass.
     
• Lithotypes to be included within Report: Choose here whether all of the material types within the Lithology Types Table are to be included in the report, or just those flagged to be included in the legend. 
• • If your Lithology Type Table lists more materials than are included in your project, there's a tool in that Table's Edit menu that will scan the project database and turn off the materials that aren't represented in the boreholes.  The materials aren't removed from the table, they're just "deactivated" from being plotted on the diagram legends.  This allows you to keep the diagram legends less cluttered.  For this Volumetrics tool, selecting "Only Lithotypes Flagged as 'Show in Legend'" tells the program to represent only those active material types in the volume report, thus not reporting materials with no volume and keeping the report less cluttered.
     
• Sort by
• • Name: Choose this option to have the material types listed in the report in alphabetical order, by name.
  • G-value: Choose this option to have the material types listed in the report in numerical order, by G-Value.
     
• Intervals: These options define the vertical portions of the model that are represented by each row within the volumetric report.
• • Every Layer:  Each row within the report will represent a layer of voxels within the solid model.
  • User-Defined:  Each row within the report will be based on a user-specified interval.  For example, if the user specifies "50" for the interval, the program will list the volume of each lithotype contained within 50-unit-thick layers within the model.  This is analogous to a mine "bench".
  • • Top-Elevation:  Elevation at which to start the report.  For example, if the user specifies 4500' for the top elevation and 50' for the interval, the first row within the report will show the volumetrics from 4500' to 4450' in elevation.
    • Base-Elevation:  Elevation at which to stop the report.
    • Interval:  Height represented by each row within the volumetric report.
       
• Decimals:  Click on this item to specify the number of decimal places to be represented in the depth intervals in the report, and the volume or mass computations.

 
Step-by-Step Summary

This tool reads an existing lithology solid model file (.RwMod), so it's necessary that you have already interpolated a lithology model using one of the other Lithology menu tools.

1. Access the RockWorks Borehole Manager program tab. 
2. Be sure you've already created the lithology model (.RwMod file) to be used.
3. Select the Lithology | Volumetrics menu option. 
4. Enter the requested menu options, described above.
5. Click the Process button to proceed with the computations.

The program will read the selected solid model. For each requested "layer" of voxels in the model, the program will compute the node count and/or volume and/or mass and/or percent of each rock type. If mass was requested, the volumes will be multiplied by the density factor. The resulting table will be displayed in a Data Tab in the Options window. 

5. You can adjust any of the options (model name, spacing) and then click the Process button again to regenerate the report.
   ! Each time you click the Process button, the existing report will be replaced.

The following example depicts the output when all of the primary options (nodes, volume, mass, & percent) have been enabled.

Tips:  Use the File | Save option to save this listing to an .RwDat file (which you can open in the Utilities datasheet).  Use the File | Export option to text or Excel.

Notes:  Be warned that the node count that's reported will be high if you select User-Defined intervals and if the model's nodes are located at the interval boundaries - they'll get counted twice.  (Volumes are not affected by this scenario and should be correct.)  Compare the following examples for a fictitious solid model that ranges from a coordinate of 0 to 100 on all three axes, with nodes placed at 0, 10. 20. 30 (etc.).

Example 1: Report showing every layer: Report extents are -5 to 105 (all axes), and the nodes lie in the middle of the reporting intervals. Node count is accurate.

Example 2: Report showing user-defined intervals:  Report extents are 0 to 100, and the nodes lie on the edges of the reporting intervals.  Nodes are counted for two layers.

 Back to Lithology Menu Summary 

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