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Computes surface-consistent static corrections by fitting the timing of a picked horizon to a reference datum. The module solves for per-source and per-receiver time shifts that, when applied, bring the specified horizon as close as possible to a flat reference level. The solution uses an iterative least-squares conjugate-gradient method. A misfit chart is produced automatically so you can monitor convergence and decide when a satisfactory solution has been reached.
Use this module when you have a reliable horizon pick (for example, a first-break or a shallow reflector) and want to derive surface-consistent statics that align that horizon to a flat datum. It is an effective data-driven alternative to model-based elevation statics and can also be applied to residual statics after an initial correction.
The seismic trace header dataset containing geometry information (source and receiver coordinates, bin locations, and datum values) for all traces. This is the primary geometry input required by the module. If source and receiver datums stored in the headers differ from each other, the module will issue a warning that the data may not be on a common datum.
The horizon picking dataset containing one or more picked horizon layers. The module reads the two-way time values at each bin location and uses them as the target times to flatten. The specific horizon layer to use is selected with the Selected hoizon parameter.
Controls the sign of the computed static shifts. Forward (default) — shifts traces upward (earlier in time) so the selected horizon aligns to the reference datum. Reverse — applies opposite-sign shifts to undo a previously applied forward correction.
Zero-based index of the horizon layer to use from the Input horizons dataset. Default: 0 (first layer). If the index exceeds the number of available layers, the module reports an error and stops.
Number of least-squares conjugate-gradient solver iterations. The misfit chart updates after each iteration. Default: 10. If the misfit curve is still decreasing at the last iteration, increase this value. Typical range: 5–50.
The surface-consistent static correction table containing one time-shift value per unique source location and one per unique receiver location. Connect this output to an Apply statics module to apply the corrections to your seismic data.
A Misfit chart plots the residual misfit against iteration number and updates after each iteration. A flat misfit curve indicates convergence; if still declining at the last iteration, increase Number of iterations and re-run.