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QC stack with statics is an interactive quality-control module for evaluating and editing surface-consistent static corrections. It stacks the entire dataset three times simultaneously — without statics, with the input statics applied, and with the output statics after any interactive editing — and displays all three stacked sections side by side so the processor can directly compare the improvement. The static correction is read from the connected static item and optionally modified by identifying and excluding bad traces.
Bad traces are identified interactively on the stack section or automatically using a semblance-based criterion. Traces marked as bad are excluded from the output statics, allowing the processor to remove corrupted or cycle-skipped corrections before applying the statics to the full dataset. The module also supports an optional sub-sequence for on-the-fly gather preprocessing before stacking.
The pre-stack seismic dataset on which the statics QC is performed.
Handle to the SEG-Y file for random-access trace reading during stacking.
Trace header table providing geometry and sorting information used to assemble CMP gathers for stacking.
Pre-sorted trace index enabling efficient CMP gather assembly across the full dataset.
RMS velocity model used to apply NMO correction internally before stacking. Required when the input gathers have not been pre-NMO-corrected.
Selects the type of static correction to be evaluated. Options: GStaticCorrectionItem (standard surface-consistent statics, default) or GAzimutalRefractionStaticCorrectionItem (azimuthal refraction statics). The selection controls which Input statics item and Output statics item connections are active.
The surface-consistent static correction to be quality-controlled and optionally edited. Connect the output of a statics estimation module (e.g., MF statics - surface consistent or Refraction statics solver) here. The module applies these statics when building the Stack with input statics section.
Container grouping NMO correction parameters applied internally before stacking.
Maximum NMO stretch limit, in percent. Default: 1%. Traces stretched beyond this fraction during NMO are muted before stacking. Set to a typical value of 20–50% for pre-stack statics QC.
Number of samples over which the velocity function is smoothed in the time direction before NMO application. Default: 10 samples. Smoothing reduces sharp transitions in the velocity function that could cause stretch artefacts.
When enabled (default: on), a bulk datum shift is applied before stacking using the Datum elevation and V0 replacement velocity. This ensures the stack section is referenced to a flat datum surface.
Datum elevation for the bulk datum shift, in metres. Default: 0 m. Active when Shift to datum is enabled.
Replacement velocity for the datum correction, in m/s. Default: 1500 m/s. Active when Shift to datum is enabled.
Maximum proportion of traces within a CMP gather that may be marked as bad before the entire CMP is excluded from the output statics. Default: 0.5%. Expressed as a fraction in the range 0.001–1. Increase this threshold if the dataset has many noisy traces that are individually bad but whose collective static can still be estimated reliably.
Container grouping parameters that control the automatic detection of bad static picks on the stacked section.
Minimum structural dip used in the semblance scan for bad-trace detection, in s/trace. Default: -0.004 s/trace. The auto-picker evaluates semblance along a range of dips to assess whether each trace is consistent with its neighbours.
Maximum structural dip for the semblance scan, in s/trace. Default: 0.004 s/trace. Set to cover the maximum expected local dip of the reflectors in the quality-control zone.
Dip increment for the semblance scan, in s/trace. Default: 0.004 s/trace. Finer steps increase sensitivity but raise computation time.
Half-width of the spatial aperture (in traces) used to compute semblance around each trace for bad-pick detection. Default: 1 trace. Larger values provide more stable semblance estimates but reduce sensitivity to spatially isolated bad traces.
Half-length of the time window used to compute semblance for bad-pick detection, in seconds. Default: 0.04 s. Set to cover at least one dominant reflection period.
Metric used to detect bad static picks. Default: By semblance. Options: By semblance, By SVR, By semblance row maximums ratio, By semblance differences, By SVR differences. The semblance-based criteria evaluate how well each trace fits the local stack; SVR-based criteria use a support-vector regression model for the detection. Use the default semblance method for most surveys; try the differences variants when the statics have already been mostly resolved and only subtle residuals remain.
Start of the time gate within which the auto-pick quality criterion is evaluated, in seconds. Default: 0 s (use the full stack). Set to the top of the zone of interest to avoid the criterion being influenced by shallow noise or water-bottom multiples.
End of the time gate for the auto-pick quality criterion, in seconds. Default: 0 s (use the full stack). Set to the base of the zone of interest.
Index of the trace to highlight in the stack display. Default: 0. When set to a non-zero value, the selected trace is highlighted in the Selected trace overlay on the stack view, facilitating focus on a specific CMP position during interactive QC.
Automatically scans the stacked section using the selected Auto pick criteria and marks traces with poor semblance scores as bad. The bad traces are displayed as markers on the stack view. After auto-picking, review the marked traces interactively and manually correct any false positives before generating the output statics.
Rebuilds all three stacked sections (before statics, with input statics, and with output statics) using the current state of the bad-trace mask. Run this action after any interactive editing of bad traces to refresh the display and verify the improvement before saving the output statics.