, and
receiver, 
, spacing is 10m. Dominant frequency of the
wavelet is 30Hz. Migration experiments were performed using both
shot-profile and source-receiver algorithms. The analysis and conclusions are
valid for both shot-geophone and shot-profile migrations due to their
mathematical equivalence Biondi (2003); Shan and Zhang (2003). However,
in practice there are subtle differences between the two that
will be discussed later.
The data so generated has been imaged with a
split-step Fourier wave equation continuation migration kernel. The
same continuation operator has been implemented in both shot-profile
and source-receiver formulations. The complex valued image at the depth
of the reflector was extracted without the normal summation of the
frequency axis to aid in interpretation. Fourier transforms of the
surface location and subsurface offset axes were then applied. Both migration
strategies were used to examine several cases of data completeness.
For the shot-profile migration example, four cases were considered: 1)
shots at every receiver location, 2) shots at every tenth receiver location,
3) shots at every tenth receiver location imaged with a
band-limited source function, and 4) shots at every tenth receiver
location imaged with the selective energy imaging condition. For the
source-receiver example, three cases were considered: 1) migration of
all CMP's, 2) migration of CMP's from shot placements every tenth
receiver location, and 3) migration of subsampled data appropriately
filled with zero-traces to regain the size of the original data set.
Despite the large decimation of the data for these experiments, care
was taken to assure that the data were still appropriately sampled
after decimation to assure that the conclusions drawn from
these results are not due to acquisition aliasing.