Change the Fiducial Numbering

In Oasis montaj, data are most typically referenced by fiducial (sample) number. You can, however, change the fiducial numbering at any time. Common reasons for changing the numbering are to correct sample positioning errors or to re-sample data (i.e., change the fiducial increment).

Change the Fiducial Numbering of a Channel (NEWFID GX)

Make sure the database you want to use is open.
On the Database Tools > Channel Tools menu, select Change Channel Fid or run the NEWFID GX. The system displays a dialog.
Select the channel (column) that you want to re-number.
Specify the new fiducial start and/or the new increment. (If the new start or increment is not specified, the current setting for start or increment will remain the same.)
Select the current line, selected lines, or all lines for processing.
Click OK. The system re-numbers the fiducials.

Change the Fiducial Numbering (and Interpolate Data) Based on a Reference Channel (REFID GX)

You can also change the reference (fiducial number) to match that of a distance, time or other channel as required.

For example, you may want to resample based on a distance channel. This type of manipulation can make sense, if you are performing Fast Fourier Transforms and want to create a new distance-based channel that is mathematically and physically more meaningful.

Or, 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.

Make sure the database you want to use is open.
On the Database Tools > Channel Tools menu, select Re-fid a Channel or run the REFID GX. The system displays a dialog.
Specify the input and output channels (columns) that you want to use as source and target channels.
Specify the channel, for instance, a time channel that you want to use as a reference.
Specify the new data increment or leave blank to use the default: smallest value in the reference channel.
Specify the new data increment or leave blank to use the default: nominal data increment of the reference channel.
Specify the gap (data with increments larger than this value are not interpolated). The default is 1.5 times the data increment.
Click OK. The system creates the new channel. The system places the re-fidded and interpolated data in the specified output channel.
The new channel should only be viewed or processed with other channels that have been resampled using the same reference channel.

Use Reading Numbers as Fiducials

If you do not have a station column in the data, or if you do not need to merge new imported data at a later date, it is not necessary to use the fiducial numbers. In this case, Oasis montaj will simply number the data on each line starting at fiducial number 0 and incrementing by 1 for each reading.

If you must import and merge more data at a later date, you may either append the data to the end of existing lines using the Merge Append option, or you can simply create new lines with the new data by using the Append option.

Use Station Numbers as Fiducials

If the data is organized as line and station, and the data file contains a X, Y and station columns, you can use the station number as the data fiducial within Oasis montaj. This has the advantage that new data that is added to the database at a later time can be merged based on the line and fiducial values.

To specify the station column as the fiducial, enter the name "Fiducial" as the channel name for the fiducial column in the import template. When you import additional data at a later date, use the same template and specify Merge as the import mode.