Composite Database
Use the option DH-Data > Composite Database (DHCOMPOSITEDB GX) to create a composite database from an input From-To database.
This GX is designed as a "wizard" that consists of three step-by-step dialogs.
Drillhole Composite Database dialog options
Fixed Interval dialog options
Interval length |
The fixed interval length. Script Parameter: DHCOMPOSITEDB.FIXINT |
Weighting channel |
Select a weighting channel from the channel list (No weight by the default). This should not be a channel containing intervals lengths -- weighting is already done using the interval weights. The values in the weighting channel are first composited to match the from-to intervals of the selected channel. Then, when the selected channel is composited, each selected channel value is multiplied by the value in the weight channel. For each output interval, the sum of the individual products is divided by the sum of the weights. In other words, a weighted sum is calculated for each composite interval. Script Parameter: DHCOMPOSITEDB.WTCH |
Next> |
Click this button to enter the rejection information. The Reject option dialog will be displayed. |
<Back |
Click this button to return the previous dialog Main dialog |
Lithological Interval dialog options
Lithology data channel |
Select a lithological data channel from the channel list. The lithology data channel must be from a From-To assay database, or an error will be registered. Script Parameter: DHCOMPOSITEDB.LITHCH |
Weighting channel |
Select a weighting channel from the channel list (No weight by the default). This should not be a channel containing intervals lengths -- weighting is already done using the interval weights.The values in the weighting channel are first composited to match the from-to intervals of the selected channel. Then, when the selected channel is composited, each selected channel value is multiplied by the value in the weight channel. For each output interval, the sum of the individual products is divided by the sum of the weights. In other words, a weighted sum is calculated for each composite interval. Script Parameter: DHCOMPOSITEDB.WTCH |
Next> |
Click this button to enter the rejection information. The Reject option dialog will be displayed. |
<Back |
Click this button to return the previous dialog |
Best-fit Lithological Interval dialog options
Lithology data channel |
Select a lithological data channel from the channel list. The lithology data channel must be from a From-To assay database, or an error will be registered. Script Parameter: DHCOMPOSITEDB.LITHCH |
Interval length |
The interval length for the best-fit lithology data. Script Parameter: DHCOMPOSITEDB.INTLEN |
Weighting channel |
Select a weighting channel from the channel list (No weight by the default). This should not be a channel containing intervals lengths -- weighting is already done using the interval weights.The values in the weighting channel are first composited to match the from-to intervals of the selected channel. Then, when the selected channel is composited, each selected channel value is multiplied by the value in the weight channel. For each output interval, the sum of the individual products is divided by the sum of the weights. In other words, a weighted sum is calculated for each composite interval. Script Parameter: DHCOMPOSITEDB.WTCH |
Next> |
Click this button to enter the rejection information. The Reject option dialog will be displayed. |
<Back |
Click this button to return the previous dialog |
Intervals from File
Interval file |
The interval file name. HoleID, From, and To values are provided in an input text file. Values should be entered one per line, and may be separated using commas, spaces or tabs. <HoleID1>, <From>,<To> <HoleID1>, <From>,<To> <HoleID1>, <From>,<To> <HoleID2>, <From>,<To> <HoleID2>, <From>,<To> <HoleID3>, <From>,<To> <HoleID3>, <From>,<To> <HoleID3>, <From>,<To> If no HoleID is specified, the From-To composite will be calculated for all selected holes. Script Parameter: DHCOMPOSITEDB.INTFILE |
Weighting channel |
Select a weighting channel from the channel list (No weight by the default). This should not be a channel containing intervals lengths -- weighting is already done using the interval weights.The values in the weighting channel are first composited to match the from-to intervals of the selected channel. Then, when the selected channel is composited, each selected channel value is multiplied by the value in the weight channel. For each output interval, the sum of the individual products is divided by the sum of the weights. In other words, a weighted sum is calculated for each composite interval. Script Parameter: DHCOMPOSITEDB.WTCH |
Next> |
Click this button to enter the rejection information. The Reject option dialog will be displayed. |
<Back |
Click this button to return the previous dialog |
Significant Intersections dialog options
Primary assay data channel |
Select an assay data channel from the channel list. The channel must be from a From-To assay database, or an error will be registered. Script Parameter: DHCOMPOSITEDB.PRIMARY_ASSAY_CHAN |
Minimum composite grade |
Output only composite intervals whose composite (weighted mean value) grade is equal to or greater than this value. Script Parameter: DHCOMPOSITEDB.MIN_COMPOSITE_GRADE |
Minimum composite length |
Output only composite intervals whose total thickness (measured along the hole) is equal to or greater than this value. Script Parameter: DHCOMPOSITEDB.MIN_COMPOSITE_THICKNESS |
Cut-off grade |
Only individual from-to intervals where the primary assay data channel's grade is greater than or equal to this value will be included in the composite interval (excluding any dilution zones). The cut-off grade may represent a geological boundary. It must be emphasized that the cut-off grade applies at the top edge and bottom edge of the interval, but not inside the interval, where the maximum dilution length and minimum dilution grade are in effect. Script Parameter: DHCOMPOSITEDB.CUTOFF_GRADE |
Clip values higher than |
If defined, from-to interval values above this amount are clipped to this amount. Also known as "maximum grade". Script Parameter: DHCOMPOSITEDB.MAX_GRADE |
Grade for missing assays |
If a from-to interval is missing, then it is assigned this value. Default is zero. Script Parameter: DHCOMPOSITEDB.MISSING_ASSAY_GRADE |
Maximum dilution length Minimum dilution grade |
Both of these parameters must be defined, or both must be left blank. Allows for short lengths inside the full composite interval where the grade can fall below the required composite grade. The minimum dilution grade is the length-weighted average grade within the dilution interval. These values do NOT apply at the top and bottom edges of the interval; see the cut-off grade for those locations. Script Parameter: DHCOMPOSITEDB.MAX_DILUTION_LENGTH, default = 1.0; s DHCOMPOSITEDB.MIN_DILUTION_GRADE, default = 0.0 |
Finish |
Click this button to begin the compositing process. |
<Back |
Click this button to return the previous dialog. |
Reject interval shorter than |
The output composite interval will be rejected if its length is shorter than this value. Leave blank to ignore this option (default). Script Parameter: DHCOMPOSITEDB.REJ1VAL |
Reject interval gaps greater than |
The output composite interval will be rejected if the accumulated length of gaps (dummies) in the interval is greater than this value. eave blank to ignore this option (default). Script Parameter: DHCOMPOSITEDB.REJ2VAL |
Reject intervals where the value of |
Select a reject data channel from the channel list (see further explanation below) Leave blank to ignore this option (default). Script Parameter: DHCOMPOSITEDB.REJ3CH |
Is … |
Select an operator from the list: > (0) , >= (1), < (2) or <= (3) (see further explanation under "Value" below) Script Parameter: DHCOMPOSITEDB.REJ3OP |
Value |
The output composite interval will be rejected if its value is >; >=; <; or <= (see above defined operator) the value of the reject data channel (see above defined) in the same interval (note that the reject data channel will be composited by the input database assay channel From-To intervals before this comparison is made). Script Parameter: DHCOMPOSITEDB.REJ3VAL |
Finish> |
Click this button to execute the GX. |
<Back |
Click this button to return the previous dialog. |
Reject Options dialog
This dialog appears when selecting one of the following compositing options: Fixed Interval, Lithological Interval, Best-fit Lithological Interval, or Interval from File.
Application Notes
This GX will create a composite database with the lines consist of the all or selected lines from the input database and the channels consist of the From, To, Mask channels and all the assay and numeric channels from the input database
The From and To channel data values are determined by the interval method and values selected. The Mask channel data values in the output database are set to 1. All assay and numeric channel data are composite values determined by the composite From/To data and the input assay channel data as well as any reject option applied
The composite method ensures that the integrated value in the output database matches the integrated value over the equivalent interval in the input database (apart from those cases where a weighting channel is used).
Significant Intersections
You can use this method to pick out significant grade intersections in your assay database.
You will have to specify an assay channel of interest and define your significant intersection criteria (i.e., minimum composite length and minimum composite grade). Using a specified cutoff grade, the tool will divide your assay intervals into high-grade and low-grade intervals. Adjacent high-grade intervals (those greater than or equal to the cutoff grade) will be composited. If the resulting composited interval satisfies your significant intersection criteria, it is added to the newly created database.
You may also specify dilution zone criteria to include small, slightly low grade intervals in the compositing. The resulting database will include the new From-To intervals, the length of the interval, and the composited data for all your assay channels. The database will also contain a channel with labels you can use in your drillhole plots.
Any missing intervals or any intervals whith the grade recorded as dummy ("*") are assigned as "Grade for missing assays."
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