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To obtain the estimates of the primaries and multiples in data space we
need to apply the inverse of the migration operator to the muted SODCIGs
of the primaries and the multiples. Here I used the adjoint of the migration
in lieu of the inverse. To assess just how good the
adjoint migration is in recovering the kinematics of the data, I first
applied the adjoint migration to the unmuted migrated SODCIGs (with the
correct velocity) and
I show the comparison between a CMP gather of the original dataset and the
migration-adjoint migration result in Figure . Clearly,
the kinematics of the reflections have been recovered fairly well, except
at the large offsets of the water-bottom primary for which the subsurface
offset sampling in the SODCIGs was a little coarse given its steep moveout
as seen in Figure (below -400 m). In the next subsection
I show that adaptive subtraction recovers these amplitudes very well.
**cmp_inv
**

Figure 6 Estimated multiples (a) and estimated
primaries (b). Some multiples leaked into the estimate of the
primaries and some primaries leaked into the estimate of the multiples.

Figure shows the
result of applying adjoint migration to the muted SODCIGs. The left panel
corresponds to the estimated multiples whereas the right panel corresponds
to the estimated primaries. Obviously, some primary energy remains in the
estimated multiples and some energy from the water-bottom primary remain
in the estimated primaries.

** Next:** Adaptive subtraction
** Up:** Methodology for attenuating the
** Previous:** Muting the primary and
Stanford Exploration Project

4/5/2006