Signal and noise separation in prestack seismic data using velocity-dependent seislet transform |

To separate pegleg multiples from primaries, we transform the data using VD-seislet frame by involving different VD slope fields (Figure 7a) according to equations 7 and 10. The primary velocities and calculated velocities of different-order pegleg multiples are shown in Figure 6b. The estimated curves of multiple velocities indicate accurate trends in velocity spectra. We use a nonlinear shaping-regularization scheme (equations 12-13) to separate different wavefield components, which are shaped to be sparse in the corresponding VD-seislet frame domain (Figure 7b). In this example, the pattern number in equation 11 is selected to be 4. The separated wavefields are shown in Figure 8 and display reasonably accurate separation results.

hask,vscan
Synthetic model (a)
and velocity trends of primaries and multiples (b).
Figure 6. |
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dips,frame
VD slopes (a) and
VD-seislet coefficients (b).
Figure 7. |
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comp0,comp1,comp2,comp3
Separated
wavefields. Primaries (a), first-order multiples (b),
second-order multiples (c), and third-order multiples
(d).
Figure 8. |
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Signal and noise separation in prestack seismic data using velocity-dependent seislet transform |

2015-10-24