Re-Fid a Channel

Use the Database Tools > Channel Tools > Re-Fid a Channel menu option (REFID GX) to change the fid sampling of a channel to be based on a reference channel. This is normally done to resample a database based on a distance channel, in which case the new fiducial will be distance.

The option is also available in the Geophysics extension under the 1D FFT > Advanced Settings > Re-Fid Back to Fiducial menu.

Re-Fid a Channel dialog options

Channel to re-fid	Select the data channel to be re-sampled. Script Parameter: REFID.IN
Resampled output channel	New re-sampled out-put channel. Script Parameter: REFID.OUT
Fid reference channel	Select the Fiducial reference channel. Script Parameter: REFID.REF
New start fiducial	The required new start fiducial. Leave blank to use the default which will be the smallest value in the reference channel. Script Parameter: REFID.START
New fiducial increment	The required new data increment. Leave blank to use the default, which will be the nominal data increment of the the reference channel. Script Parameter: REFID.INCR
Maximum gap to interpolate	The gaps in the data larger than this will not be interpolated. The default is 1.5 times the data increment. Script Parameter: REFID.GAP
Interpolation method	The interpolation method to use, one of "Linear", "Minimum Curvature", "Akima" or "Nearest". Script Parameter: REFID.METHOD

Application Notes

The new channel should only be viewed or processed with other channels that have been resampled using the same reference channel.

For example, if you wish to work with a data channel using evenly sampled ground units, create a distance channel using the DISTCHAN GX, then resample the X, Y and data channels to the data increment that you require. The X, Y and data fiducials now represent ground distance units.

If you refid a channel, the channel can be resampled in relation to other channels and/or the original fiducial. The system places a red line underneath the channel name to indicate this.