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This module is deprecated and is no longer recommended for new projects. Use the current Radon demultiple or HR Radon multiple attenuation modules instead.
Multiples Suppression attenuates multiple reflections in pre-stack seismic gathers using a velocity-based stretch-mute approach. The module applies NMO correction to the input gather using the supplied RMS velocity field, stretches the corrected traces by a user-defined factor to discriminate multiples (which stretch more than primaries after NMO), and then mutes the stretched portion. When subtraction mode is enabled, the predicted multiple model is adaptively subtracted from the input gather rather than hard-muted. The module accepts both parabolic (Up) and linear (Down) stretch-mute directions to handle different multiple geometries.
Container for the standard input data connections. Connect this to the output of the preceding module in the processing sequence.
The input pre-stack seismic gather on which multiple suppression is applied. This gather should be in the offset-time domain and must have trace geometry (bin header) assigned.
The RMS velocity gather used to apply NMO correction before the stretch discrimination. Connect this to the output of a velocity analysis module or a velocity model reader. The module selects the velocity trace nearest to the current input gather location.
The fractional stretch threshold used to discriminate multiples from primaries after NMO correction, expressed as a percentage. The default is 1 (100%). After NMO, a sample is considered to belong to a multiple and is muted if the stretch at that offset-time position exceeds this factor. Reduce this value to remove more energy (more aggressive muting); increase it to preserve shallow events at the cost of less multiple attenuation.
The number of neighbouring traces used in the lateral smoothing of the multiple model before subtraction. The default is 10. Increasing this value applies more lateral averaging, which can stabilise the subtraction in areas of low S/N but may over-smooth lateral multiple variations.
Reserved parameter — not used in the current implementation. The default is 10.
Selects the direction of the stretch-mute discrimination. Up (default) mutes samples above the stretch threshold, targeting surface-related multiples that have higher moveout than primaries. Down mutes samples below the threshold, targeting events with lower moveout such as interbeds.
When enabled (default: true), the module subtracts the predicted multiple model from the input gather rather than applying a hard mute. Subtraction mode preserves primary energy that overlaps with multiples in the stretch zone. Disable this option to apply a conventional hard stretch mute without adaptive subtraction.