Import Drillholes from Excel or Access Files
Summary
Imports subsurface drillhole or borehole data from Excel or Access source files (.xls, .xlsx, .mdb, .accdb) to a feature dataset in a geodatabase.
Usage
The imported drillhole data will be stored in a feature dataset (called "Drillholes" by default), with feature classes created for each data type that is associated with the imported drillholes:
- Collars (point features, surface location of each drillhole)
- Traces (polylines, created from collar and survey data)
- Interval data sets ("from-to" data line segments of varying lengths along the drillhole trace, with attributes)
- Point data sets (point features that are located along the hole trace, with attributes)
Before importing drillholes from Excel or Access files, you are asked to choose the output geodatabase in which to store the drillhole data and the spatial reference system that will be assigned to the feature dataset. You can also choose how to treat any existing data, if this is a second or subsequent import. If drillhole data already exists in the current drillhole data dataset, the option to overwrite or append to existing data will be made available.
Parameters
Parameter | Explanation | Data Type |
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Import into existing Drillhole dataset |
This determines if the import will create a new drillhole dataset, or if the data will be imported into a pre-existing drillhole dataset:
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Output Drillhole Dataset |
The name of the geodatabase feature dataset in which to store the imported drillhole data. |
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Spatial Reference (Optional) |
The coordinate system (CS) to be used to spatially reference the imported drillhole data. Click on the Select coordinate system button to select the appropriate CS from the available options or add a new one.
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Existing data |
If the data will be imported into an existing drillhole feature dataset, this determines if the newly imported data will overwrite existing data, or not:
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Source data |
The Excel or Access file (.xls, .xlsx, .mdb, .accdb) that contains the drillhole data. |
Excel, Access (.xls, .xlsx, .mdb, .accdb) |
Use import template files? |
This determines if the import will use pre-existing templates or the import wizard to import the data:
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Collar data |
Drillhole collar data defines the surface location of a drillhole. Collar data has 5 required fields:
Hole Collar data can also include Azimuth, Dip, and various attribute fields.
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Survey data |
Drillhole survey data contains hole deviation information, and requires 4 fields:
Survey data is optional. See the Technical Notes section below for more details.
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Interval (from-to) data |
Interval, or "from-to" data: data acquired over specified depth intervals ("from-to depths") down the hole. This can be categorical data such as lithology, weathering, alteration or mineralization, or numeric data such as geochemical assays. From-To data must include the Hole ID, Depth From, Depth To and some type of attribute data values.
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Point (depth) data |
Point data, or single depths: data acquired in discrete measurements made at specific depths. This can be structural data measurements, or geophysical logs. Point data must include the Hole ID, Depth and some type of attribute data values.
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Template |
The template file (with a file extension"i4") to be used to import the data file. Enabled if Use import template files? is checked. |
I4 File (.i4, .ii4) |
Data |
The data source specified in the selected Template file. The data source and the type of data specified in the template files will be used to import the Drillhole data. |
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Technical Notes
Installing a 64-bit Access Database Engine
In order to be able to import data from Excel or Access files, you will need to install the latest 64-bit Access database engine.
If you are unable to install the latest 64-bit Access database engine because you have an existing 32-bit office installation, please install the 2010 64-bit Access database engine using the steps described here.
Template Files
Drillhole data that has been previously imported to any version of Target, may have saved template files. Import template files contain all of the import parameters including data source type (e.g. Excel, Access), data source location, and the type of data (Collar, Survey, From-To, Point), so these import parameters do not need to be specified again. These templates are useful to re-import data using the same settings, or to import new data with the same formatting. If no import templates are provided, the import wizard ('Drillhole Import') will be shown to select the type and format of the data to be imported.
Learn more about Template Files.
Desurveying Drillholes using Collar and Survey Data
The drillholes are always "desurveyed" on import, which means a 3D spatial object (a drillhole "trace") is calculated for each drillhole. The output trace for any given hole can vary depending on what type of data is available during import (collars only, vs. collar and survey data) and which method is selected to do the desurvey calculations, as well as the resolution value selected. The various ways to calculate the traces, depending on which types of data are available, are described below:
With collar locations only, no survey data present:
- If collar data includes dip and azimuth, these values are used to create straight segment traces for the entire hole, to the final depth.
- If collar data does not include dip and azimuth, the holes are assumed to be vertical.
With collar locations and dip-azimuth survey data:
- The survey data is "discretized" at the desurvey resolution interval value and a smooth curve is generated using the selected desurveying method (the default is the "Radius of curvature" method). See Drillhole Settings for more details.
- Holes are 'desurveyed' and the new trace geometries are stored in the Traces, Depth Ticks, From/To and Point datasets.
- The top-of-hole dip and azimuth values (at depth = 0) will use the values from the Survey feature class, if present.
- If top-of-hole survey values are not present, the collar dip and azimuth values will be used instead (with the collar values taking precedence).
Learn more about Recalculate Holes.
Append Data to Existing Dataset
When drillhole data is imported into an existing drillhole feature dataset, the following process is followed:
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New drillholes: the holes are added to the existing data.
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Existing drillholes with new From-To intervals entries: the entries are appended to the existing drillholes.
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Existing drillholes with matching From-To intervals: the data is left unchanged.
Related Topics
Drillhole Import Wizard:
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