Georeference IP Database

Use Georeference IP Database to georeference the local electrode coordinates.

Georeference IP Database dialog options

IP Database to Georeference

Database

Select the IP Database to georeference. This database must contain the transmitter and receiver positions in the local coordinate system. On output, depending on the IP configuration, it would contain up to 12 georeferenced channels.

If the Lookup database contains an elevation channel, a set of electrode Z channels will be generated.

The output channels will have the general syntax ENM where:

  • E is Tx for Transmitter and Rx for Receiver

  • N is 1 or 2

  • M is X , Y, and Z

Script Parameter: GEOREFERENCE_IPDATABASE[*].IP_DATABASE

Channel lookup

In the local coordinate system (CS), the transmitter and receiver positions may be defined using one or two coordinates. In the local CS, the IP lines are generally either parallel to the abscissa or the ordinate. In this case, select the Station option. The other coordinate will be extracted from the line’s position.

However, if the electrode positions in the local CS are defined using both the abscissa and ordinate, select Along line & Across line. For clarity, since the IP lines may be along any azimuth direction, the coordinates are defined relative to the IP line direction, rather than in terms of X & Y.

Script Parameter: GEOREFERENCE_IPDATABASE[*].IP_LOOKUP_CHANNELS [0- Station (default), 1 – Along line& Across line]

Transmitter 1 & 2

Receiver 1 & 2

This tool is cognisant of the IP configuration and shows the appropriate number of tabs.

If you have selected the Station option above, for each electrode, you will be prompted to enter the channel that contains the electrode positions along the survey line.

Script Parameter: GEOREFERENCE_IPDATABASE[*].[e]X[n]_STATION Where [e] is T or R [n] is 1 or 2

If you selected the Along line & Across line option above, for each electrode, you will be prompted to enter two channels containing the electrode positions along the survey line and across (normal).

Script Parameter: GEOREFERENCE_IPDATABASE[*].[e]X[n]_ALONG

Script Parameter: GEOREFERENCE_IPDATABASE[*].[e]X[n]_ACROSS

Where

[e] is T or R

[n] is 1 or 2

Electrode Location Database

Database

Select the database containing the georeferenced electrode positions. In order to look up the georeferenced locations, this database should share line names and one or two reference channel names with the IP database.

Script Parameter: GEOREFERENCE_IPDATABASE[*].GEOREFERENCE_DATABASE

Channel lookup

The lookup can be performed using one or two coordinates. If the electrode positions in the georeferenced CS are defined using a single coordinate channel, select Station. However, if the electrode positions in the georeferenced CS are defined using both the abscissa and ordinate, select Along line & Across line. Normally, this should be the same selection as for the local coordinate system.

Script Parameter: GEOREFERENCE_IPDATABASE[*]. LOCATIONS _LOOKUP_CHANNELS [0- Station (default), 1 – Along line& Across line]

X

Y

Z channel

Select the X,Y,Z georeferenced channel names from the electrode location database. These are the values that are transferred over to the IP database.

Script Parameter: GEOREFERENCE_IPDATABASE[*].[X|Y|Z]_CHANNEL

Electrode position channel(s)

If you selected the Station option above, you will be prompted to enter the Station channel name that contains the electrode positions along the survey line.

Script Parameter: GEOREFERENCE_IPDATABASE[*].POSITION_CHANNEL

If you selected the Along line & Across line option above, you will be prompted to enter the Along line & Across line channel names that together contain the electrode positions in the local coordinate system.

Script Parameter: GEOREFERENCE_IPDATABASE[*].REF_ALONG

Script Parameter: GEOREFERENCE_IPDATABASE[*].REF_ACROSS

Coordinate system

If the electrode location database carries projection information, it is shown here and gets transferred to the IP database. Otherwise, this field becomes enabled and you can specify the projection.

 

 

[*] {

 

= TWO_CHANNEL_LOOKUP
= empty

The parameter group adjusts to indicate if using a two channel lookup.

Application Notes

IP surveys are normally conducted on a local coordinate system. For practical reasons, the data QC is also generally conducted on a local coordinate system. Subsequently to display IP data with other geophysical and geological information, and to invert the data, it must be georeferenced.