HOLES3D Process

To access this process:

Enter "HOLES3D" into the Command Line and press <ENTER>.
Display the Find Command screen, locate HOLES3D and click Run.

See this process in the Command Table.

Process Overview

Note: This is a superprocess and running it may have an effect on other Datamine files in the project.

HOLES3D converts a set of downhole sample data, collars location data and optionally downhole survey data, into a 'desurveyed' static drillholes file in which each sample is identified by its location (X,Y,Z coordinates) and direction (azimuth and dip) in space.

Note: HOLES3D is used by Drillhole Importer.

In the 'desurveyed' form, each drillhole sample is identified independently in 3D space without reference to its neighbours.

If two or more downhole sample files are specified (maximum 10) then they are merged so that all divisions of all sets of samples are maintained. A typical use of merging is to add an assay file to a lithology file, where the lithology intervals do not match the assay sample boundaries. Another example is to add absent data samples into holes by making the second file a single record per hole defining the total hole length.

The output from the HOLES3D process is in the standard drillhole format which is used elsewhere in your application. For example the drillholes can be viewed interactively, composited downhole, and used to interpolate grades into a block model.

Using Downhole Survey Data

The downhole survey data is optional. If a survey file is not specified it is assumed that all the drillholes are vertical. If the survey file only includes a subset of the total number of drillholes, then it is assumed that all drillholes which are not included in the survey file are vertical. In both cases a warning message is displayed. The positions at which the survey readings are recorded does not have to correspond to sample positions.

Important: A maximum of 50,000 survey measurements can be processed for each hole. If the number of points exceeds 50,000 then a subset will be selected so that the total number of points is less than 50,000.

The IDs of all holes that use a subset of survey points are displayed with the progress messages in the Command Window. The IDs are also added to the ERRORS file. The HOLESMRY file shows the number of survey points processed for all holes.

Each drillhole in the downhole survey data file should have a survey measurement at its collar (AT=0). If this is not the case then the process will automatically move the first survey measurement to the collar position. A warning is issued and a list of all offending holes is displayed. If moving the survey position is not appropriate then you should edit the survey data file and rerun the process.

The process works by first computing a set of positions in space at known coordinates down each hole, and then interpolating between these known points for the top and bottom of each sample. The interpolation uses arcs of circles separately in horizontal and vertical planes.

The process will optionally calculate the XYZ coordinates of the start and end of each sample. This is controlled by parameter ENDPOINT, which if set to 1 will create the six extra fields. These coordinates can be useful for creating a DTM of the top or bottom of a seam or stratum.

As well as creating the desurveyed file, the process will optionally create two other files which assist in validating the input data. The HOLESMRY file contains a summary of the drillholes in each of the input files. It shows the number of records in each input file for each drillhole. The ERRORS file contains a list of:

surveys from the Downhole Survey file,
samples from the Downhole Sample file(s),
collars from the Collars file

which do not pass the validation tests. The tests are detailed in the description of the ERRORS file.

If the HOLESMRY file shows that one or more of the input data files do not contain entries for every drillhole then a warning is displayed. A warning is also issued if there are any entries in the ERRORS file. In order to correct any errors it will be necessary for you to edit the input data files and rerun the process.

You are encouraged to use the optional HOLESMRY and ERRORS files. You should also take careful note of the output display to see whether any warnings have been issued. If there are any warnings it is strongly recommended that you fix the data problems before using the desurveyed file for subsequent processing.

The SURVSMTH Parameter

When a hole sample is desurveyed the survey data (azimuth and dip) of the sample is used to locate the sample centre point in space. A desurveyed drillhole file contains a set of samples each with a calculated center point in XYZ world space.

Sometimes raw drillhole data tables to be desurveyed may contain more than one survey record within one sample, each with different azimuth and dips. Since a sample is by definition a straight line its location in space cannot be calculated using more than one survey record. The SURVSMTH parameter is used to automatically divide up samples where more than one survey records lie within a sample.

The samples are split in half until only one survey record lies within each sample. Therefore many samples may be created. The default value of SURVSMTH is 1 which will cause extra samples to be created so that no sample contains more than one survey record within its FROM and TO values. For no extra samples to be created the SURVSMTH parameter should be set to zero.

If the SURVSMTH parameter is set to zero and a sample does contain more than one survey record not all survey records will be taken into account. Traditionally this has been resolved by first compositing the samples to reduce their lengths. The SURVSMTH parameter avoids this requirement.

It is often the case that the first one or two samples in exploration holes contain more than one survey record because they are relatively long. This is because sample divisions have not had to have been created through assay and lithological identification near the surface

Defining Dip and Bearing

@DIPMETH determines the dip convention used to describe hole data. It can be set to 1 to ensure that positive dip values point downwards, or -1 to point upwards.

Things get more complex if there is a a mixture of survey data from the input collar table and an input survey table, containing its own dip and bearing information. In this situation, where both data exists:

Survey records in the collar table (in the DIP and BRG columns) are used (when available) if no other survey records are found for that hole. That is, if survey records exist in both the collar table and survey table for a hole, only records in the survey table are used (and collar records for that hole are ignored).
If no survey records exist for a hole in the survey table (but a survey table is specified), the DIP and BRG values from the collar table are used instead.
- If the collar table contains absent DIP or BRG records, the hole is set vertically.

Regardless, all survey records (either in &COLLAR or &SURVEY) respect the DIPMETH parameter.

Input Files

Name	Description	I/O Status	Required	Type
COLLAR	Data file of drillhole collar locations. Expects fields BHID, XCOLLAR, YCOLLAR and ZCOLLAR.	Input	Yes	Collars
SURVEY	Optional survey data file. Expects fields BHID, AT, BRG, DIP. If a borehole has Survey Data, then it must include a record for the collar location, i.e. AT=0. If a survey file is not specified it is assumed that all holes are vertical. If the survey file only includes a subset of the total number of holes, then it is assumed that all holes which are not included in the survey file are vertical.	Input	No	Downhole Survey
SAMPLE1-10	Sample data files. This file is compulsory and must include fields BHID, FROM, and TO. It will probably also include at least one sample attribute field, such as grade or lithology.	Input	Yes	Downhole Sample

Output Files

Name	I/O Status	I/O Status	Required	Type
OUT	Output desurveyed sample data file. This will include fields BHID, FROM, TO, LENGTH, X, Y, Z, A0, B0, and all other fields which were included in the sample file(s). The X,Y and Z fields are the coordinates of the centre of each sample. The A0 and B0 fields are the azimuth and dip of the sample, respectively. This cannot be the same file name as ERRORS (see below) For more information on Downhole Survey files, click here.	Output	Yes	Drillhole
HOLESMRY	Optional output file containing a summary of the drillholes in each of the input files. It shows the number of records in each input file for each drillhole identifier (BHID). This can be very useful for validating the data, and showing what data is missing from which holes.	Output	No	Table
ERRORS	Optional output file containing a list of surveys and samples which do not pass the validation tests. This cannot be the same file name as the OUT file (see above). Tests 1-4 refer to the SURVEY file, tests 5-7 are applied to the data in files SAMPLE1 to SAMPLE6, and test 7 is on the COLLAR file a survey file has been specified. each BHID has a survey reading for AT=0. each BHID in the (merged) sample file has at least one entry in the SURVEY file. the downhole TO value of a sample is greater then the downhole FROM value. Holes with more than 10,000 survey points are identified. Only a subset will be processed. the FROM/TO interval for one sample does not overlap the FROM/TO interval of the next sample. the FROM/TO interval is not duplicated. XCOLLAR, YCOLLAR and ZCOLLAR are not absent data. Only one of the errors 4-6 will be reported even if a sample fails more than one of these tests. The output file will contain the following fields: - FILE: the name of the file in which the error was identified, - PROBLEM: a brief description of the problem, - BHID: the drillhole identifier, - FROM: the downhole FROM distance of the sample, - TO: the downhole TO distance of the sample. In order to correct the problems it will be necessary to edit the original data files.	Output	No	Table

Fields

Name	Description	Source	Required	Type	Default
BHID	Drillhole identifier.	COLLAR, SAMPLE1, SURVEY	No	Any	BHID
XCOLLAR	X co-ordinate of drillhole collar.	COLLAR	No	Numeric	XCOLLAR
YCOLLAR	Y co-ordinate of drillhole collar.	COLLAR	No	Numeric	YCOLLAR
ZCOLLAR	Z co-ordinate of drillhole collar.	COLLAR	No	Numeric	ZCOLLAR
FROM	Downhole distance to sample top.	SAMPLE1	No	Numeric	FROM
TO	Downhole distance to sample bottom.	SAMPLE1	No	Numeric	TO
AT	Downhole distance to survey point.	SURVEY	No	Numeric	AT
BRG	Bearing of drillhole.	SURVEY	No	Numeric	BRG
DIP	Dip of drillhole. Dip values must always be positive when referring to the downwards direction if using this command in a batch process. For more information on Downhole Survey files, click here.	SURVEY	No	Numeric	DIP

Parameters

Name

Description

Required

Default

Range

Values

SURVSMTH

Option	Description
0	Prevent samples being added to the output file.
1	add samples where there are more than one survey record per sample.

The samples are split in half until only one survey record lies within each sample. Therefore many samples may be created. The default value of SURVSMTH is 1 which will cause extra samples to be created so that no sample contains more than one survey record within its FROM and TO values. For no extra samples to be created the SURVSMTH parameter should be set to zero.

0,1

ENDPOINT

set to 1 to include the X, Y and Z coordinates of the start and end of each sample in the desurveyed output file. Fields XSTART, YSTART, ZSTART, XEND, YEND and ZEND are created in the output file.

0,1

DESURVMD

Locate sample centers or end points on the desurveyed arcs. The default is 1, to accurately locate the sample center points.

=0 : To accurately locate sample END points on the desurveyed arcs.

=1 : To accurately locate sample CENTER points on the desurveyed arcs.

0,1

DIPMETH

Set to 1 to ensure that positive dip values point downwards, or -1 to point upwards.

See "Defining DIP and BeaRinG", above.

0,1

INCLMISS

INCLude MISSing samples parameter.

0: the OUT file will not include FROM / TO intervals that were missing from the input sample files
1: the OUT file will include a record for every missing FROM / TO interval in the input sample files. The grades will all be set to absent data

0,1

PROMPT

Set to 1 (default) to pause HOLES3D execution if an error occurs. Set to 0 to continue processing script if errors are encountered (useful when running HOLES3D from script as processing will continue).

0,1

KEEPNAME

Determine how field names are treated during processing.

0: any non-standard field names are converted to standard field names in output files.
1: non-standard field names are carried through to the output files.

0,1

Option	Description
1	to display each individual process which is run by the HOLES3D superprocess.

0,1

Example

!HOLES3D &COLLAR(collars), &SURVEY(surveys), &SAMPLE1(assays), &SAMPLE2(lith), &OUT(assay.d), &HOLESMRY(holesmry), &ERRORS(errors),

*BHID(BHID), *XCOLLAR(XCOLLAR), *YCOLLAR(YCOLLAR), *ZCOLLAR(ZCOLLAR), *FROM(FROM), *TO(TO), *AT(AT), *BRG(BRG), *DIP(DIP),

@ENDPOINT=0.0

Error and Warning Messages

Message	Description	Solution
No Survey File	The specified survey file can be found, or one is not specified. Process will terminate	Specify a valid survey file for &SURVEY
No Survey AT=0	One or more records has been found with a zero distance to a survey point	Review input data and resolve/remove unexpected data, or accept results as expected.
No Survey Data	No valid survey data can be found in the specified survey column	Review input data and resolve unexpected data
TO < FROM	One or more records exist where the TO value is less than the FROM value	Review input data and resolve/remove unexpected data, or accept results as expected.
Sample Overlap	Overlapping sample information has been found in one or more input hole component files	Review input data and resolve/remove unexpected data, or accept results as expected.
Duplicate FROMs	One or more duplicate FROM values has been found in input data	Review input data and resolve/remove unexpected data, or accept results as expected.
Absent collars	One or more drillholes has no corresponding collar specification.	Review input data and resolve/remove unexpected data, or accept results as expected.
Duplicate collars	One or more duplicate collar values has been found in input data	Review input data and resolve/remove unexpected data, or accept results as expected.
Duplicate surveys	One or more duplicate survey records has been found in input data	Review input data and resolve/remove unexpected data, or accept results as expected.
Out of range DIP/BRG	One or more DIP and or BRG values has been detected outside of the expected range.	Review input data and resolve/remove unexpected data, or accept results as expected.
Out of range AT	One or more AT values has been detected outside of the expected range.	Review input data and resolve/remove unexpected data, or accept results as expected.
Absent FROM/TO	One or more samples is missing a FROM or TO value	Review input data and resolve/remove unexpected data, or accept results as expected.
Duplicate TOs	One or more duplicate TO values has been found in input data	Review input data and resolve/remove unexpected data, or accept results as expected.
Could not find Datamine file collars	The file name entered for the collars files cannot be found.	An alternative file name must be provided before the process can proceed.
Output holes and errors file cannot be the same	The same file name has been specified for OUT and ERRORS	Make file names unique for OUT and ERRORS
Duplicate collars exist in file COLLAR	Duplicate collar positions have been found in COLLAR file	Review input data and resolve duplicate information, or accept results as expected.
Duplicate survey records exist in file SURVEY	Duplicate collar positions have been found in SURVEY file	Review input data and resolve duplicate information, or accept results as expected.
Out of range or absent values for BRG and DIP exist in file SURVEY	Survey file contains absent or unexpected data records for either BRG or DIP (or both). This could be negative values or values > 360	Review input data and remove unexpected data, or accept results as expected.
Out of range or absent values for AT exist in file SURVEY	Survey file contains absent or unexpected data records for AT	Review input data and remove unexpected data, or accept results as expected.
xxx holes have survey data, but do not have a survey point at the collar (AT=0). The problem has been accounted for during desurveying by resetting the AT value of the first survey point to AT=0. However you should correct your survey file.	Survey file contains missing survey point information at collar position (AT=0)	Correct survey file

Note: "out-of-range" can include any unexpected data input, including negative values.