Seismic Data Compression And Its Effect On the Amplitudes

We investigate the impact of lossy seismic data compression on the amplitudes of a North Sea 2-D seismic data set processed conventionally. Processing includes attenuation of waterbottom multiples, true amplitude recovery, predictive deconvolution, attenuation of peg-leg multiples, prestack time migration, and stacking. Two sequences of the lossy compression method are investigated. In the first sequence the seismic data are compressed before predictive deconvolution (denoted predecon compression), while in the second sequence the seismic data are compressed after predictive deconvolution (denoted post-decon compression). Both prestack and poststack amplitude analysis are performed. For pre-decon and post-decon compression, compression ratios between 7.5:1-15:1 and 15:1-30:1, respectively, provide excellent reconstruction quality of the seismic data set. In general, migration and stacking reduce the effect of the coding noise at all compression levels, while for high compression ratios (i.e., much greater than 10:1) the coding noise has a destructive effect on the predictive deconvolution step and on the two applied multiple attenuation methods.