1.8 Processing Selected Gathers It may be desirable to restrict ANOMALOUS_AMP_ATTEN to process only selected portions of the input data. For example, if it is possible to identify certain parts of the input dataset as the areas where anomalous noise is a problem then one could use more aggressive thresholds on this area while leaving the non-noisy regions untouched. This allows the SFM to attack the noise while reducing the risk of removing useful signal from the data. The GATHER_SELECT parameter set may be used to specify a condition to use to either include or exclude gathers from processing. Gathers that are included are put through the normal actions of ANOMALOUS_AMP_ATTEN. Gathers that are excluded from processing are written to output with no changes to the seismic data. The intended use for this option is to run some type of data analysis SFM against the input data and to insert a diagnostic value into the trace header. This value can then be used to decide whether or not to apply the ANOMALOUS_AMP_ATTEN processing.