Scanning Seismic Data - SN Evaluation and AUTO Quality
This section describes an automatic process used to evaluate the signal-to-noise (SN) ratio of each record in a seismic data file [*(SR)*.dat]. Definition of SN ratio is based on the five attributes of an overtone record (processed from each seismic record) as outlined in the overview; Pattern, Coherency, Definition, Amplitude, and Energy. The evaluation results can be used to infer the overall "quality" of original seismic field records. In consequence, they can also be used to evaluate the relative confidence level of the final velocity (Vs) cross section by considering the record range that was responsible for specific lateral area in the cross section. Range of SN values and corresponding quality descriptions are presented in the table below:
Table 1: Description of SN evaluated and corresponding attributes.
||Best quality for AUTO process. Highly reliable results are expected
||Good candidate for AUTO process. Reliable results are expected
||Marginal quality for AUTO process. Results should be used with caution.
||Lowest quality for AUTO process. Results should be used with caution.
||Data should not be used for AUTO process.|