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Working on migration to zero-offset (MZO) in variable velocity
media, I encountered a problem with the formulation of my MZO operator:
while the operator is accurate in depth variable velocity, it is defined
in the offset-wavenumber domain, and therefore has to be applied
to all the offsets at the same time. As people apply DMO to
constant-offset sections,
I had to look at how to separate the operator so it could
be applied to individual offsets. My MZO
formulation (Popovici, 1993)
is very similar to prestack migration in Fourier
domain which also applies a phase-shift operator
in offset-wavenumber domain.
Therefore I decided to apply the offset separation technique
to prestack Fourier domain migration as it is a well known
operator and researchers are more familiar with its formulation.
I present two methods for applying phase-shift migration to separate
constant-offset sections. One method is faster when applied to all
the offsets at the same time. However, this method migrates
all the constant-offsets at the same time, so it is inefficient
when a single constant-offset migrated image is desired.
The second method
migrates one constant-offset at a time, but requires more time
to migrate all the offsets.

I also discuss the source of artifacts present in offset domain
and explain how they can be avoided by a careful implementation
of the algorithm.

** Next:** DSR equation
** Up:** Popovici : Offset separation
** Previous:** Popovici : Offset separation
Stanford Exploration Project

11/16/1997