Drillholes Grade from Control Points/ Control Strings

Intelligent Mining Software “Solutions”

MineMap IMS - Drillhole Grades

from Control Points/ Control Strings

TABLE OF CONTENTS

INTRODUCTION 3

DRILLHOLE GRADES FROM CONTROL POINTS 4

The Files Page 5

The Selection Page 6

The Drillhole Names Page 8

The Survey Record Creation Page 9

DRILLHOLE GRADES FROM CONTROL STRINGS 10

The Files Page 11

The Selection Page 12

The Drillhole Names Page 13

APPENDIX A: A WORKED EXAMPLE FOR CONTROL STRINGS 14

INTRODUCTION

A common procedure used by many mine surveyors involves coding of the blast hole or channel sample number information into the comment field of the survey data. Grade control options are then used to process the reduced data and enter the information directly into a database in a form suitable for merging with the assay results returned from the laboratory.

MineMap IMS can import survey data for grade control via the standard MineMap IMS CAD file. The sample and drillhole number is coded in the comment fields of points and strings in the CAD file. These fields are used to interpret the blast hole / channel pick-up on a bench-by-bench basis and to load this information directly into CSV files.

DRILLHOLE GRADES FROM CONTROL POINTS

1. Drag the MineMap IMS CAD file containing the coded comment fields from the File Explorer Pane to either the 3D View Pane or the Loaded File Pane.

2. Select the <Drillholes<Grade<From Control Points…> menu item (Figure 1) to display the first page of the grade control wizard (Figure 2).

Figure 1: Selecting the “Grades From Control Points” menu item

The Files Page

Figure 2: Specifying CSV files for output

1. Enter a unique file name for the Header. This is a text file in CSV format containing the collar information (hole name, easting, northing and RL) for the grade control holes.

2. Enter a unique file name for the From/to information. This is a text file in CSV format containing the assay information (interval, sample number and bench) for the grade control holes.

3. Enter a unique file name for the Surveys. This file is a text file in CSV format containing the survey information (dip, depth and azimuth) for the grade control holes. If this field is left blank then the survey information will be included in the Header file.

4. Press the <Next> button.

The Selection Page

Figure 3: Control point parameters

1. Enter the template used by the comment field of the survey file.

2. Enter the field termination character. This can be any character but should be chosen with care to avoid conflict with other information. Characters such as “/”, “:” and “;” are safe choices.

If this character is not specified then the comment field has to be exactly consistent with the number of characters found in the template.

3. Enter the bench name if it is not contained within the comment field and referenced through the “B” code.

4. Enter the sample thickness if it is not contained within the comment field and referenced through the “T” code.

5. Select the check box if samples should be created from matching records.

MineMap IMS caters for data files derived from channel sampling, costean and underground face sampling. Sample holes need points at the start and end of each hole with the same template format (i.e. the start and end points have the same comment field). Each pair of points must be adjacent. The first point is used for collar information while the second point is used for the azimuth, dip and number of samples.

6. Select one of the methods to ensure unique sample numbers.

7. Press the Next button.

NOTES

1. If you use a field termination character such as “/’, then the comment can contain any number of characters up to a terminating “/”.

2. The template “H/S/N” means that the characters up to the first “/” delimiter is the hole name, the characters up to the next “/” delimiter is the starting sample number and the last character is the number of samples in the hole.

If there are ten or more samples per hole then the template will read “1” instead of “10”. This is because there is no “/” after the “N” so “N” specifies a single character. In this case the template should be “H/S/NN”.

EXAMPLE

If the initial sample number is “142” then the sequence of sample numbers that can be generated are as follows:

Increment starting from the given sample number

142, 143, 144, ...

Multiply by 10 and increment

1420, 1421, 1422, ...

Multiply by 100 and increment

14200, 14201, 14202, ...

Multiply by 1000 and increment

142000, 142001, 142002, ...

The Drillhole Names Page

Figure 4: Naming drillholes

1. Select the order of the items that will be appended to the drillhole name.

2. Enter the alphanumeric text if required.

3. Enter the width of the sample number field if required. Leading zeroes will be added to pad the sample number up to the required width.

4. Enter the width and starting value of the increment field if required. Leading zeroes will be added to pad the increment up to the required width.

5. Press the <Next> button.

A text string is generated using the information provided and it becomes either the hole name or is appended to the hole name already obtained from the “H” code in the point’s comment field (Figure 3).

The Survey Record Creation Page

Figure 5: Creating survey records for non-vertical drillholes

1. Select the check box if surveys records are required for non-vertical drillholes.

2. Enter the azimuth and dip of the survey records.

3. Press the <Finish> button.

NOTE: Create Samples from Matching Records (Figure 3) takes precedence over this page.

DRILLHOLE GRADES FROM CONTROL STRINGS

1. Drag the MineMap IMS CAD file containing the coded comment fields from the File Explorer Pane to either the 3D View Pane or the Loaded File Pane.

2. Select the <Drillholes<Grade<From Control Strings…> menu item (Figure 6) to display the first page of the grade control wizard (Figure 7).

Figure 6: Selecting the “Grades From Control Strings” menu item

The Files Page

Figure 7: Nominating output CSV files for control strings

1. Enter a unique file name for the Header. This is a text file in CSV format containing the collar information (hole name, easting, northing and RL) for the grade control holes.

2. Enter a unique file name for the From/to information. This is a text file in CSV format containing the assay information (interval, sample number and bench) for the grade control holes.

4. Press the <Next> button.

The Selection Page

Figure 8: Control string parameters

1. Enter the template used by the comment field of the survey file.

If this character is not specified then the comment field has to be exactly consistent with the number of characters found in the template.

3. Enter the bench name if it is not contained within the comment field and referenced through the “B” code.

4. Press the Next button.

The Drillhole Names Page

Figure 9: Naming drillholes

1. Select the order of the items that will be appended to the drillhole name.

2. Enter the alphanumeric text if required.

3. Enter the width of the sample number field if required. Leading zeroes will be added to pad the sample number up to the required width.

4. Press the <Next> button.

APPENDIX A: A WORKED EXAMPLE FOR CONTROL STRINGS

The operation of drillhole grades from control strings is similar to drillhole grades from control points, except that the drillhole samples produced correspond exactly to the strings that exist in the input MineMap IMS CAD file. Each string produces a drillhole with each segment in the string producing a sample. Two survey records are produced for each sample, one at the start and one at the end of the sample. The collar of the drillhole (easting, northing, elevation) is set to the location of the first point in the string.

The comment field of the points making up the strings is used to create sample numbers. Note that each segment has a point at the start and end of the segment. The comment of the end point of the segment is used for the sample number information.

A sample MineMap IMS CAD file is shown in Figure 10.

7066.83 12004.76 557.770 1 200501

7076.83 12006.76 557.770 2 200502

7073.90 12006.92 557.783 3 200503

7063.90 12004.92 557.783 4 200504

STRPOL 1 0.000 4 1

1 2 3 4

Figure 10: A sample MineMap IMS CAD file

The sample MineMap IMS CAD file is then parsed using the following comment field format SSSSSS (i.e. 6 characters of sample number) to generate hole names formed from the sample number prefixed with an "H".

The parsed file produces the drillhole data CSV files shown in Figure 11, Figure 12 and Figure 13.

holename, easting, northing, elevation,

H200501, 7066.830, 12004.760, 557.770,

Figure 11: The collar CSV file produced from the sample

holename, downdepth, azimuth, dip,

H200501, 0.00, 78.69, 0.00,

H200501, 10.19, 78.69, 0.00,

H200501, 10.20, -86.87, 0.25,

H200501, 13.12, -86.87, 0.25,

H200501, 13.13, -101.31, 0.00,

H200501, 23.32, -101.31, 0.00,

H200501, 23.33, -101.31, 0.00,

Figure 12: The survey CSV file produced from the sample

holename, samp_from, samp_to, samplenumber,

H200501, 0.00, 10.20, 200502

H200501, 10.20, 13.13, 200503

H200501, 13.13, 23.33, 200504

Figure 13: The assay CSV file produced from the sample

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