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Shift multi-line gathers applies static time shifts and optional phase rotations to seismic gathers across multiple 2D lines or 3D sub-volumes simultaneously. The module is designed for multi-line geometry conditioning workflows where individual lines need to be corrected relative to each other — for example, to remove residual static differences at line intersections before cross-line merging or joint inversion.
Shift values are loaded from an external ASCII file (produced by a cross-line tie or intersection analysis workflow). The module reads each input line, applies the spatially interpolated time shift trace-by-trace, optionally rotates the phase, and writes the result to a new SEG-Y output file. The output files have the same name as the inputs with a configurable suffix appended. If no suffix is specified, the original files will be overwritten after user confirmation.
A collection of trace header sets — one per input seismic line. Each entry provides the spatial positions (bin coordinates X, Y) of all traces on that line. These positions are used to match traces against the intersection points loaded from the ASCII shifts file, so that the correct time shift is assigned to each trace.
A collection of SEG-Y data handles — one per input seismic line, paired in order with the Trace headers collection above. Each handle points to the SEG-Y file from which the seismic data will be read and to which the shifted output will be written (with the configured suffix). The number of handlers must match the number of trace header sets exactly.
A text string appended to each input file name (before the extension) to form the output file name. For example, if the input is line01.sgy and the suffix is _shifted, the output will be written to line01_shifted.sgy. The default suffix is _shifted. If you clear this field and leave it empty, the module will ask for confirmation before overwriting the original input files in place.
The maximum distance (in meters) within which a trace position is considered to match an intersection point from the loaded shifts file. For each trace, the module finds the nearest intersection point using a spatial search tree. If the distance between the trace and that nearest point is within this aperture, the corresponding shift value is applied. Traces outside the aperture receive no shift correction. The default value is 5 m. Increase this value if your lines have coarser spatial sampling or if intersection coordinates contain rounding errors. Decrease it if lines pass very close together and you need to avoid applying the wrong intersection shift.
When enabled, the module displays the loaded shift values as a point map in the Location map view, coloring each trace position by its assigned time shift. This is useful for visually verifying that shifts have been loaded correctly and are distributed as expected across all lines before running the computation. The default is off. Enable it when you want to inspect the shift map after loading from the ASCII file.
Specifies the SEG-Y encoding format used when writing output files. This includes the data sample format (e.g., IBM floating point, IEEE floating point, 16-bit integer) and other binary header settings. Set this to match the format expected by downstream applications or to preserve consistency with the input files.
Defines how trace header fields are mapped in the output SEG-Y files. The default option is Geomage Format. Select an alternative format if the output must conform to a different header convention used by your processing system or interpretation software.
Selects whether the module runs on the CPU or GPU. For this module the computation is lightweight and CPU execution is typical.
Controls whether the processing is distributed across multiple compute nodes in a cluster environment.
Sets the minimum number of lines processed per distributed job chunk.
When enabled, restricts the number of CPU threads used on each distributed node to the value set in the Number of threads parameter.
An optional label appended to the distributed job name to distinguish this run from others in the cluster queue.
When enabled, allows manual specification of CPU core affinity for this process, overriding the system default scheduling.
Specifies the CPU cores to which this process should be bound when Set custom affinity is enabled.
Sets the number of parallel CPU threads used for the shift computation. Increasing this value speeds up processing when many lines are shifted in one run. The module applies shifts trace-by-trace across all lines in parallel up to this thread limit.
When enabled, the module is bypassed entirely and no processing is performed. This is useful for temporarily disabling this step in a workflow without removing it from the sequence.
The module writes one output SEG-Y file per input line. Each output file is named by appending the configured suffix to the original file name. The output data contains the same geometry and trace headers as the input, but with each trace shifted in time according to the spatially interpolated static correction derived from the loaded ASCII shifts file. If phase rotations were specified in the shifts file, these are also applied to each trace before writing.
Opens a file browser to select a tab-delimited ASCII text file containing the intersection shift table. The file must have exactly 10 tab-separated columns per data row: intersection X coordinate, intersection Y coordinate, and fields describing line names, time shifts (in seconds), and phase rotations (in degrees) for the two intersecting lines at each point. This action populates the internal shift database used during execution. After loading, enable Update GUI to verify the spatial distribution of shifts in the Location map view.
Removes all currently loaded shift and rotation values from memory after user confirmation. Use this action before reloading a revised shifts file to ensure no stale data from a previous load is retained.