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This module attenuates acquisition footprint noise in 3D post-stack seismic data by applying a 2D spatial smoothing filter slice by slice. For each time slice in the seismic cube, the module computes the instantaneous envelope and instantaneous phase using the Hilbert transform, applies a configurable inline and crossline smoothing operator to the envelope, and then reconstructs the output trace by multiplying the smoothed envelope by the cosine of the instantaneous phase. The result suppresses coherent spatial amplitude variations caused by irregular receiver geometry (footprint) while preserving the underlying reflectivity signal.
Use this module on stacked 3D data after migration when periodic spatial amplitude striping related to the acquisition geometry is visible in time slices or amplitude maps. The Load Volume and Apply Slice custom actions allow interactive QC of the footprint removal result on individual time slices before running the full volume.
Container for the standard input data connections. Connect this to the output of the preceding module in the processing sequence.
The input 3D seismic gather (Common-Offset or stacked volume) on which footprint removal is performed. The gather must be organized as a crossline-over-time gather at each inline position, or as a continuous-offset (CO) gather, so that the module can assemble a 3D cube internally for slice-by-slice processing.
The index of the time slice to display when using the interactive Apply Slice custom action. Changing this value updates the In, Out, and Footprint visualisation panels so you can inspect the footprint removal quality at a specific time level before processing the entire volume.
The time sample index (count from zero) at which footprint smoothing begins. Slices above this index are passed through unchanged. Set this to skip the shallow water-bottom or direct-arrival zone where the footprint attenuation is not needed or would be harmful.
The amplitude threshold below which traces are treated as zero-amplitude (dead) for the smoothing step. The default is 0. Increase this value to exclude low-energy traces in areas of minimal fold from contributing to the smoothed envelope, preventing the footprint estimator from being biased by near-zero signal in under-sampled regions.
Container for the 2D spatial smoothing filter parameters applied to the instantaneous envelope on each time slice.
The half-width of the smoothing filter in the inline direction (number of traces). The default is 10. Increase this value to smear the footprint estimate over a larger inline distance, producing stronger attenuation of long-wavelength inline amplitude striping.
The half-width of the smoothing filter in the crossline direction (number of traces). The default is 10. Typically this should be set to the same value as Smooth inline for isotropic footprint attenuation. Increase it independently if the acquisition footprint pattern is predominantly in the crossline direction.