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Statics - Surface Consistent Experimental computes surface-consistent residual static corrections by cross-correlating NMO-corrected CDP gathers against a CMP stack model trace. The module operates as a sequence-level procedure that processes the full dataset in multiple iterations, decomposing the measured time shifts into source and receiver components using a least-squares approach. Optionally, it can also compute and apply a residual moveout (RMO) correction at each CMP location to further flatten the gathers before the surface-consistent decomposition step.
Note: This module is deprecated and retained for legacy workflow compatibility. For new projects, consider the current Surface Consistent Statics workflow.
The seismic dataset to process. Connect from the preceding module in the sequence. The data should be NMO-corrected unless Input gathers type is set to Gathers without NMO.
The SEG-Y file handle used for random-access reading of the input data during multi-iteration processing.
Trace header table containing source and receiver geometry. Used by the solver to associate computed time shifts with their corresponding surface locations.
Start time (s) of the cross-correlation window used to estimate residual static shifts. Default: -0.001 s (use full trace length). Set to the two-way time of the shallowest reflector of interest to exclude shallow noise from the analysis window.
End time (s) of the cross-correlation analysis window. Default: -0.001 s (use full trace length). Set to the two-way time of the deepest reflector of interest.
Replacement velocity (m/s) used to convert solved delay times into time-shift corrections when applying a datum shift. Default: 1500 m/s. Set to the same replacement velocity used in the associated datum static correction step.
Maximum allowed residual static shift (s) per trace. Default: 0.02 s. Minimum: 0.001 s. Shifts estimated to exceed this value are clipped. Set to the maximum expected residual after first-pass long-wavelength statics have been applied; typical values are 0.010–0.040 s.
Number of solver iterations used to converge the surface-consistent static decomposition. Default: 10. Minimum: 1. Each iteration re-estimates the source and receiver statics from the residual misfit of the previous pass. Most datasets converge in 5–15 iterations. Inspect the convergence diagnostic to confirm the solution has stabilised.
Determines how the cross-correlation peak is selected. Default: Global. Global selects the absolute maximum of the cross-correlation function within the allowed shift range. Local selects the first local maximum that exceeds a user-defined percentage of the global maximum, which can help avoid cycle-skip artefacts on noisy data. When Local is selected, the Local max within percent of global parameter becomes active.
When Pick max mode is Local, specifies the minimum amplitude of a local peak as a fraction of the global maximum (0 to 1). Default: 0.10. A value of 0.10 means any local peak at least 10% as large as the global maximum is considered a valid pick. Increase to require a stronger peak; decrease to allow weaker local peaks. Active only when Pick max mode is Local.
When enabled (default), a short-wavelength CMP correction is computed and applied in addition to the main surface-consistent statics. This removes residual shift patterns that are common to all traces in a CMP gather. Disable if the long-wavelength static solution alone is sufficient or if the CMP correction introduces artefacts. When enabled, the CMP aperture parameter becomes active.
Spatial radius (m) around each CMP location used to gather neighbouring CDPs when computing the CMP correction. Default: 250 m. A larger aperture produces a smoother CMP correction map; a smaller aperture captures more local detail. Active only when Use CMP correction is enabled.
When enabled, the module estimates and applies a residual moveout correction to each gather before the surface-consistent decomposition. Default: off. Enable when the input data has residual NMO velocity errors that could bias the static estimates. When enabled, the Tau aperture, Delta tau, Min fold, and RMO smooth step parameters become active.
Half-aperture (s) of the tau (time shift) search range used for the RMO semblance scan. Default: 0.1 s. The RMO correction is searched within ±Tau aperture around the current NMO-corrected reflection time. Active only when Use RMO correction is enabled.
Step size (s) of the tau search grid during the RMO semblance scan. Default: 0.001 s. Smaller values give a finer scan resolution at the cost of longer computation. Active only when Use RMO correction is enabled.
Minimum number of live traces required in a CMP gather for the RMO correction to be computed at that location. Default: 10. Locations with fewer live traces are skipped to prevent unstable semblance estimates. Active only when Use RMO correction is enabled.
Spatial smoothing radius (m) applied to the RMO correction map before it is subtracted from the data. Default: 100 m. Larger values produce a smoother RMO correction, which helps prevent over-correction of spatially sparse data. Active only when Use RMO correction is enabled.
Time radius (s) around a user-picked horizon used when computing the horizon-guided cross-correlation analysis. Default: 0.030 s. Traces are cross-correlated within a window centred on the horizon pick ± this radius. A larger radius captures more signal energy but may include events from adjacent reflectors.
Container grouping the stack display parameters. Enable Create stacks to compute and display inline and crossline base stacks within the module interface for QC.
When enabled, the module builds inline and crossline stacked sections through the survey volume for display in the Graphics panel. Default: off. Enable before running to enable interactive QC of the statics solution.
Inline number for which the inline base stack is displayed. Active when Create stacks is enabled.
Crossline number for which the crossline base stack is displayed. Active when Create stacks is enabled.
Container grouping the NMO correction settings applied to raw gathers before the statics analysis.
Specifies whether the input data is already NMO-corrected or requires on-the-fly NMO. Default: NMO Gathers. Select Gathers without NMO to let the module apply NMO internally using the provided Vrms model before computing the statics.
RMS velocity model used for internal NMO correction when Input gathers type is set to Gathers without NMO. Connect from a velocity analysis module.
Maximum NMO stretch (as a decimal fraction, e.g., 1 = 100%) applied during internal NMO correction. Default: 1. Samples stretched beyond this threshold are muted.
Number of samples used to smooth the velocity function in the depth/time direction before applying internal NMO. Default: 10 samples. Smoothing prevents abrupt velocity changes from generating high-frequency NMO artefacts.
Container grouping the datum shift settings. When Shift to Datum is enabled, the module applies an elevation static to move data from topography to the specified processing datum before cross-correlation.
When enabled, applies a datum shift to the data before computing statics. Default: off. Enable when the data has not already been shifted to the processing datum.
Target datum elevation (m) for the shift-to-datum operation. Default: 1000 m. Active when Shift to Datum is enabled.
Container grouping the horizon-guided cross-correlation settings. A horizon can be picked interactively in the inline and crossline display panels to guide time-window cross-correlations on specific reflectors.
Name of the currently active horizon layer. Select the horizon to view or edit from the drop-down list populated by the horizon import or interactive picking operations.
Grid spacing (m) used to interpolate the picked horizon in the X direction when creating the horizon map. Default: 200 m. Minimum: 1 m.
Grid spacing (m) used to interpolate the picked horizon in the Y direction. Default: 200 m. Minimum: 1 m.
Container grouping the settings used when importing a horizon from an ASCII file via the Import horizon ASCII custom action.
Specifies whether the horizon times in the ASCII file are measured from the processing Datum or from Topography. Default: Datum.
Reference datum elevation (m) used when the Location is set to Datum. Default: 0 m.
Units of the time values in the ASCII horizon file. Default: Milliseconds. Select Seconds if the input file contains times in seconds.
Runs a full-fold CMP stack of the input data to create the base reference stacks used for cross-correlation and QC display. Execute this action before picking horizons or computing the statics solution.
Opens a file browser to load a horizon from an ASCII text file. The imported horizon is used to guide the cross-correlation analysis window. Configure the Import horizons from ASCII params settings before using this action.
Saves the currently active horizon (selected by Current layer) to an ASCII text file for use in other modules or external applications.
Recomputes the horizon interpolation map from the current set of user picks or imported horizon data, applying the Interpolation step X and Y grid parameters. Run this action after modifying picks to refresh the displayed horizon map.