Page 394 - Acquisition and Processing of Marine Seismic Data

7.4 RADON VELOCITY FILTER 385

FIG. 7.19 (A) A brute stack section, and its τ-p domain predictive deconvolution results with a constant prediction lag of
α ¼ 160 ms for different operator lengths of (B) n ¼ 160 ms, (C) n ¼ 200 ms, and (D) n ¼ 240 ms. M represents the first-order
seabed multiple.

Because the velocity used in NMO correction is undercorrected one (like the hyperbolas of
almost always higher than the velocity of the multiple reflections) exhibits positive residual
multiples, multiple reflection hyperbolas cannot moveout value. If the hyperbola is exactly flat-
be completely flattened and they exhibit a resid- tened after NMO correction, as expected for
ual moveout shown by Δt 1 , Δt 2 , and Δt 3 in primaryreflections, then therewillbenoresidual
Fig. 7.20B. An overcorrected reflection hyperbola moveout in the τ-p domain. Therefore, when
produces negative residual moveout, while an we transfer the NMO corrected gather in