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In order for the migration-demigration process to yield useful results, the
offset sampling of the CMPs, as well as the subsurface offset sampling of the
SODCIGs must satisfy the well-known aliasing condition:
with . This condition
is easy to satisfy for the CMPs but is much more difficult for the SODCIGs,
in particular for the water-bottom multiple which has a steep moveout as
shown in Figure . Therefore, if we want to attenuate the
water-bottom multiples we may need to interpolate the subsurface-offsets
before the adjoint migration. This will obviously increase the cost of the
adjoint migration. It may be better to attenuate the water-bottom
multiples in the time
domain since there moveout is predictable and apply the procedure described
here to the data without the water-bottom multiples.

** Next:** Muting in CMPs
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Stanford Exploration Project

4/5/2006