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The SC Statistics module collects amplitude and phase statistics from the seismic dataset to support surface-consistent (SC) processing workflows. It analyses seismic energy separately for each source and receiver location across a user-defined frequency band, building a spectral profile for every station in the survey. The resulting statistics are used by the SC Amplitude Correction and SC Deconvolution modules to equalise source- and receiver-side imbalances in amplitude and phase.
The module operates in two stages that can be run sequentially or independently using the Custom Actions: first, raw statistics are built across the configured frequency band; second, a surface-consistent amplitude solution is computed by iterative least-squares inversion. The graphical output includes a location map, gather views, a spectrum histogram, and an amplitude-frequency map for QC.
The SEG-Y data handle connecting to the pre-stack seismic dataset from which statistics will be gathered. All traces in the defined offset and time window are used to build the surface-consistent model.
The trace header vector providing source and receiver station identifiers used to assign amplitude statistics to each surface location.
An optional pre-computed statistics file. When provided, this file is loaded instead of re-building statistics from the raw data. Use this to re-run the inversion step with different solver settings without re-reading the entire dataset.
Parameter group controlling how the spectral statistics are collected from the data. The frequency band is divided into steps and amplitude statistics are built independently in each sub-band.
The width of the cosine taper (in Hz) applied at the edges of each frequency sub-band when computing the spectral statistics. A taper of 10 Hz creates a smooth transition between bands and reduces spectral leakage. Default: 10 Hz.
The lowest frequency (Hz) included in the statistics analysis. Set this to the low-cut frequency of the useful signal band. Frequencies below this value are excluded from the surface-consistent model. Default: 1 Hz.
The highest frequency (Hz) included in the statistics analysis. Set this to the high-cut frequency of the useful signal band to avoid measuring noise-dominated spectral characteristics. Default: 90 Hz.
The frequency step (Hz) used to divide the analysis band into sub-bands. Smaller steps produce a finer spectral resolution in the statistics but increase computation time. Default: 5 Hz.
Parameter group controlling the iterative solver that decomposes the amplitude statistics into separate source (CS) and receiver (CR) correction terms. The correction terms are computed independently at each frequency step.
Selects the decomposition domain for the surface-consistent amplitude solution. CS CR decomposes the data into source and receiver components only. CS CR Offset adds an offset-dependent term, which is useful when significant offset-dependent amplitude variations are present (e.g., AVO anomalies). Default: CS CR Offset.
The number of iterations performed by the least-squares solver when computing the surface-consistent amplitude corrections. Increase this value if the solution has not converged (check the amplitude correction maps for smooth, geologically reasonable patterns). Typical values are 20–500. Default: 10.
The minimum amplitude threshold (as a percentage) below which a statistics sample is excluded from the surface-consistent inversion. Samples with very low energy (e.g., dead or noisy traces) are filtered out to prevent them from biasing the correction. Default: 0.01%.
The number of traces loaded into memory at once when reading the seismic dataset. Larger buffer sizes improve I/O throughput on fast storage systems but require more RAM. Default: 5000 traces.
The beginning of the time window (in seconds) used for collecting amplitude statistics. Set this to the top of the reflection zone of interest, below the mute zone. Default: 0 s.
The end of the time window (in seconds) used for collecting amplitude statistics. Set this to the deepest target horizon of interest. Default: 10 s.
The shortest source-receiver offset (in m) included in the statistics. Near-offset traces may be affected by direct wave or refraction energy; increase this value to exclude them. Default: 0 m.
The longest source-receiver offset (in m) included in the statistics. Far-offset traces may have reduced signal-to-noise ratios; reduce this value to exclude them if necessary. Default: 100000 m.
The apparent velocity (in m/s) of the first-arriving energy, used to define a mute cone that excludes direct arrivals, refractions, and air-wave energy from the statistics. Samples arriving before this velocity curve are discarded. Default: 100000 m/s (effectively no first-break mute).