Distant Electrodes

Use the IPLNINFO GX to set distant electrode parameters for a selection of lines in the database. This GX is sensitive to the array type (i.e. Dipole-Dipole, Pole-Dipole, Pole-Pole and Gradient) and displays for adjustment only the relevant parameters for each type. The displayed values are those obtained from the current line.

Distant Electrode dialog options

Line

The Line name is displayed.

Array Type

The Array type is displayed.

Current Electrode X (T1X)

Current Electrode X (T1Y)

Current Electrode X (T1Z)

Near current electrode positions. The distance current electrode location. This location is used to calculate apparent resistivity. If X or Y is left blank, it is assumed that the electrode is at infinity. If the Z value is left blank, then no topographic correction can be applied for calculated resistivities.

Script Parameter: IP.T1X, IP.T1Y, IP.T1Z

Current Electrode Y (T2X)

Current Electrode Y (T2Y)

Current Electrode Y (T2Z)

Distant current electrode positions. These are requested for pole-dipole, pole-pole and gradient surveys. If X or Y is left blank, the electrode is considered to be at infinity for the purpose of calculating apparent resistivity.

If the Z value is left blank, then no topographic correction can be applied for calculated resistivities.

Script Parameter: IP.T2X, IP.T2Y, IP.T2Z

Potential Electrode X (R2X)

Potential Electrode Y (R2Y)

Potential Electrode Y (R2Z)

Distant potential electrode positions. These are requested for pole-pole surveys. If X or Y is left blank, the electrode is considered to be at infinity for the purpose of calculating apparent resistivity.

If the Z value is left blank, then no topographic correction can be applied for calculated resistivities.

Script Parameter: IP.R2X, IP.R2Y, IP.R2Z

Export to lines

Selecting this button exports the existing stored distant electrode locations to channels in the database. The values currently displayed in the dialog (for the current line) are ignored in this operation, so changes made to those values before pressing the Export to lines button are also ignored. The export is done to all lines selected using the line selection tool.

  • This export will overwrite any existing values, so if you have manually altered the distant electrode location in a given line, you will lose them if you have selected that line.
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    OK

    Select the OK button to modify the distant electrode locations for the selected lines.

    Use the "Select Lines to Update" tool to select the lines (and/or deselect lines previously selected) to be modified.

    Application Notes

    The values used to calculate apparent resistivity are stored inside each line’s registry, and the same values are used for the entire line. However, if channels with the correct names for the distant electrodes exist (depending on the dipole configuration -- T1X, T1Y, T1Z, T2X, T2Y, T2Z, R2X, R2Y, R2Z), and the values contained therein are NOT all dummies, then these values will take precedence and be used in calculations of apparent resistivity to populate the "ResCalc" channel.

    Once the electrode locations are selected, a list of all the lines in the database is displayed. Select those lines to update with the entered electrode locations. For scripting, enter the names of the lines to update, separated by commas: Script Parameter: IPLNINFO.LINES (Example: IPLNINFO.LINES="L700,L800").

    Handling Multiple Distant Electrode Locations in a Single Line 

    The IP system can handle line data  with more than one set of distant electrode locations. This normally occurs when new data, with different electrode locations, is appended to existing data in a line. The following procedure is recommended:

    1. Before importing the second data set, run this GX and use the Export to lines button to export existing, stored distant electrode settings to new channels in the database.
    2. Import the second data set, with the Append to existing data option. The new distant electrode locations are saved along with the old ones in the appropriate channels.
    3. Do not select the Export to lines button a second time, as it will overwrite all the distant electrode locations with the original distant electrode locations.