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Trim statics - Edit applies spatial smoothing or median filtering to a field of per-trace trim static shifts that was previously calculated by Trim statics - Calculate. Because individual cross-correlation estimates can be noisy, especially on gathers with low signal-to-noise ratio, spatial editing reduces outlier shifts and produces a geologically consistent correction surface before the shifts are applied to the data.
The module can operate in two modes. In Gather mode it reads the trim static values stored in the trace headers of the incoming gather and writes the smoothed values back to the output headers. In Trace headers on disk mode it reads and updates trim static values directly from a stored trace header file, which is useful for editing previously saved statics without reprocessing the full seismic sequence. After editing, connect the output to Trim statics - Apply to shift the traces.
The seismic dataset whose trace headers contain the trim static shifts to be edited. Connect the output of Trim statics - Calculate or a data-load module here.
Handle to the SEG-Y file for the primary dataset. Required for the Gather work mode when trace data is accessed alongside the headers.
Trace header table carrying the per-trace trim static values (written by Trim statics - Calculate) to be spatially filtered.
Current gather from the processing sequence. Used in Gather work mode to provide spatial context for the smoothing aperture.
Stack line passed through for downstream modules.
Crooked-line definition for 2D surveys processed along irregular acquisition lines.
3D bin-grid definition used for inline/crossline addressing of the spatial smoothing aperture in 3D surveys.
Pre-sorted trace index used to efficiently locate neighbouring gathers within the smoothing aperture.
Handle to the on-disk trace header storage file. Required when Work mode is set to Trace headers on disk, allowing the module to read and update the trim static field directly without loading the full seismic dataset.
Selects the data source from which trim static values are read and to which the smoothed values are written. Default: Gather.
In Gather mode the module processes each gather as it flows through the sequence and updates the trim headers in memory. In Trace headers on disk mode the module operates directly on a saved trace header file, editing all traces in a single pass without re-reading seismic amplitudes. The disk mode is efficient for post-processing the static field after the main processing sequence has completed.
Path and filename for the output file when Work mode is Trace headers on disk. The smoothed trim static values are written to this file. If the file already exists, its handling is controlled by the Rewrite output if exists option.
Controls how data is written to the output file in Trace headers on disk mode. Direct writes each block immediately as it is processed. Append adds data to the end of an existing file. Use Append when continuing an interrupted processing run or when combining results from multiple partial runs.
Number of trace headers read or written in a single I/O operation when working in Trace headers on disk mode. Larger values improve disk throughput but require more memory. The default is suitable for most datasets; increase it on systems with fast storage and ample RAM.
When enabled, an existing output file at the specified path is overwritten without prompting. When disabled, the module will abort or warn if the output file already exists, preventing accidental data loss.
Forces the output file to be recreated from scratch even if Rewrite output if exists is disabled. Use this option when you need to guarantee a clean output file at the start of a reprocessing run.
The trace header field that identifies which trim static shift is associated with each trace within a gather. Default: OFFSET. In most pre-stack workflows the offset uniquely identifies a trace within its gather. Select DATA_USE if the workflow uses that header field for trace identification instead.
Half-width of the spatial smoothing aperture in the inline direction, measured in number of CMPs. Default: 2. The filter considers all gathers within ±ApertureInline CMPs of the current position. Larger values produce smoother statics but may smear genuine short-wavelength variations. For 2D surveys this value controls the along-line aperture.
Half-width of the spatial smoothing aperture in the crossline direction, measured in number of CMPs. Default: 2. For 2D surveys or single-line geometries this parameter can be set to 0. In 3D surveys match the inline and crossline apertures to the expected lateral wavelength of the near-surface static variation.
Spatial filter type applied to the trim static field. Default: Median.
The Smooth option computes a weighted average of the static values within the aperture, producing a gradually varying correction field. Use Smooth when the statics are expected to vary slowly and continuously across the survey.
The Median option replaces each value with the median of its neighbourhood, which is more robust to outliers caused by bad traces or cycle-skip errors. The Confidence interval parameter is applied only with the Median filter to further reject values that differ excessively from the local median.
Threshold for outlier rejection when Edit type is Median, expressed as a fraction in the range 0–1. Default: 0.9. Values that fall outside the top (1 − ConfidenceInterval) fraction of the local distribution are flagged as outliers and replaced by the local median. A value of 0.9 means that only the top 10% most deviant statics are replaced. Increase this threshold towards 1.0 for more aggressive outlier removal; decrease it towards 0.5 to preserve more of the original variation.
When enabled, g-Platform automatically connects compatible data items from the preceding module in the sequence. Disable this option if you need to manually wire specific input connections.
Determines how the module responds when NaN or infinity values are detected in the input data. Fix replaces bad values with zero before processing. Notify logs a warning and continues. Continue silently proceeds without modification.
Cache parameters controlling how SEG-Y data blocks are pre-loaded into memory for the Trace headers on disk work mode. Tuning these parameters can improve I/O performance on large surveys by reducing the number of individual read operations.
Selects the compute device for processing. CPU execution is the default and is available on all systems. GPU execution can accelerate the spatial filtering on large 3D surveys when a compatible CUDA device is present.
Options for distributing the static editing across multiple processing nodes in a cluster environment.
Minimum number of gathers dispatched to each processing node as a single work unit. Larger values reduce scheduling overhead at the cost of less fine-grained load balancing.
Caps the number of CPU threads used per cluster node. Useful when the node hosts other concurrent jobs and full-core utilisation would cause resource contention.
Text appended to the distributed job name for identification in cluster job queues. Useful when running multiple simultaneous processing flows.
Enables manual specification of CPU core affinity for the processing threads. When disabled, the operating system scheduler assigns cores automatically.
The specific CPU core or core range to which the processing threads are pinned. Only active when Set custom affinity is enabled.
Number of parallel CPU threads used for processing. Set to 0 to use all available logical cores. Reducing this value can free resources for other concurrent processes.
Enables execution of custom scripts before and/or after this module runs. Use this option to trigger external tools, send notifications, or perform file management tasks as part of the processing flow.
Path to a script that is executed immediately before the module starts processing. Can be used to prepare input files or check preconditions.
Path to a script that is executed immediately after the module finishes. Can be used to copy or archive the output files or notify downstream processes.
When enabled, this module is bypassed and input data is passed through unchanged. Use Skip to temporarily disable static editing without restructuring the processing sequence.
The primary output dataset with updated trim static values in the trace headers. Connect this to Trim statics - Apply to apply the smoothed shifts to the seismic traces, or to a save module to archive the corrected header field.
SEG-Y file handle propagated downstream for use by subsequent read/write modules.
Updated trace header table containing the spatially edited trim static shift values, ready to be consumed by Trim statics - Apply.
The output gather with trace amplitudes unchanged and updated trim static headers. Connect to the next module in the sequence.
Stack line passed through unchanged for downstream modules.
Crooked-line definition passed through to downstream modules.
Bin grid passed through to downstream modules, unchanged.
Sorted trace index passed through to downstream modules.