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The methodology to attenuate the multiples consists of four basic steps:
prestack migration of the data with a migration velocity
such that .
Estimation of the multiples and the primaries by tapered mute of the SODCIGs
to eliminate the primaries and the multiples, respectively. Adjoint migration of the estimated primaries and multiples and adaptive subtraction of the
estimated multiples from the original data with the estimated primaries
used as a weighting function to restrict the adaptive subtraction to the
multiples only.
I will now illustrate each of these steps with one gather of the synthetic
dataset.
**sodcigs1
**

Figure 4 SODCIG migrated with the correct velocity
(a) and with 90% of the correct velocity (b).