Page 408 - Acquisition and Processing of Marine Seismic Data

7.7 SURFACE-RELATED MULTIPLE ELIMINATION 399

FIG. 7.34 A stack section (A) before and (B) after SRME (top) and their corresponding autocorrelograms (bottom).
M represents surface-related multiples.

matching filter between predicted and While most multiple elimination methods are
recorded multiples is designed and applicable in 2D and unable to account for 3D
applied. effects, SRME can be formulated in 3D,
v. Adaptive subtraction: Recorded shots and although it is much more expensive and com-
predicted multiples are compared and the plex to apply. Application of 2D SRME to 3D
multiples are adaptively subtracted from data is not recommended, since the accuracy
the input. of the prediction depends on the amount of
crossline dip. If the 3D survey is dense enough
Although several multiple suppression with no feathering, and contains large apertures
approaches exist in the marine seismic data for in-line and crossline directions, then the
processing industry, SRME is one of the most multiples are almost completely eliminated by
effective and widely used methods today. Its 3D SRME. However, existence of feathering
main advantage is that it does not require any on the streamers and too narrow apertures,
model of the subsurface structure, such as especially for long offsets, commonly restrict
velocity information, seafloor picking, etc. the success of 3D SRME.