** Next:** Choosing the migration velocity
** Up:** Alvarez: Multiple attenuation
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There are several important issues with the above methodology that can
impact the quality of the results. Making sure that the adjoint migration
operator is a good approximation to the inverse of the migration operator
can probably provide the biggest improvement. Here I used a standard
wave-equation migration without any compensation for the migration Jacobian.
Other important factors that are relatively easy to control are: choosing the
right migration velocity, avoiding aliasing for the adjoint migration of the
SODCIGs, choosing the appropriate tapered mutes for the estimation of the
primaries and the multiples, choosing the threshold amplitude to compute
the weight mask and muting the direct wave and the water-bottom primary
reflection. I will discuss my current understanding of these issues now: