Translations:Vibroseis/2/en

During earlier days, the correlated vibroseis traces constituted the final result for interpretation. Today, we no longer consider it prudent merely to correlate the vibroseis trace with the swept-frequency signal because we now realize that this step inserts an interpreter wavelet at the front end of the processing sequence. Most processing is designed to deal with physical wavelets, which are causal. But the zero-phase interpreter wavelet is noncausal and two-sided and thus interferes with standard processing. In other words, the older initial correlation for vibroseis records should not be carried out. It only adds trouble. The signature-free trace described above avoids this trouble. Ideally, signature deconvolution should be carried out by each crew in the field so that processing centers receive clean records that are compatible with those coming from other seismic crews (Robinson and Saggaf, 2001).