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This module reconstructs synthetic source and receiver positions for each trace in a 2D dataset by combining the trace CDP position, its offset value, and the survey's stack (crooked) line geometry. For every trace, the CDP picket location along the line is determined, and the source and receiver are then placed symmetrically on either side of that point at a distance equal to half the absolute offset value. The resulting coordinates are written back into the trace headers as updated source and receiver positions.
This module is useful when source and receiver coordinate headers are missing or unreliable in a 2D survey and only CDP number and offset are available. The stack line defines the physical path of the acquisition line, so all computed source and receiver positions follow the true geometry of the survey. Note that this module is marked as deprecated; it is retained for backward compatibility with older processing workflows.
The collection of seismic trace headers to be processed. Each trace must have a valid CDP bin assignment and an offset value stored in its headers. The module uses the CDP position to locate each trace on the stack line and uses the offset to calculate where the source and receiver should be placed. Binning must have been applied to the traces before running this module; if no bin information is found, the module will report an error.
The 2D stack (crooked) line that defines the physical path of the seismic survey line. This line provides the spatial framework used to convert picket distances into real-world XY coordinates. The stack line must include valid first and last picket and CMP reference points. The module can optionally extend this line beyond its endpoints (see the Distance parameter) so that source and receiver positions for near-end traces can be computed correctly.
The distance (in meters) by which the stack line is extended beyond both its start and end points before computing source and receiver locations. Default value: 0 m (no extension).
For traces near the ends of the line, the half-offset may place the source or receiver beyond the physical extent of the stack line. Set this value to a distance at least as large as the maximum half-offset in your dataset to ensure all synthetic positions can be computed. The line is extended linearly in both directions following the local azimuth of the endpoint segment. If all traces fall well within the interior of the line, this parameter can be left at 0.
Controls which side of the CDP point the source and receiver are placed on. Default value: off.
When this option is off (default), the source is placed at CDP + half-offset and the receiver at CDP - half-offset along the line picket. When this option is on, the assignment is reversed: the source is placed at CDP - half-offset and the receiver at CDP + half-offset. Choose the setting that matches the sign convention used for offset in your dataset's trace headers, so that the reconstructed source and receiver positions correctly reflect the actual shot-receiver geometry.