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Tomographic methods are needed for estimating a velocity model that
varies rapidly along the lateral direction.
In previous reports I presented the theory (Biondi, 1988) and
the synthetic results (Biondi, 1989) of a velocity-estimation
method capable of reconstructing velocity anomalies shorter than the
cable's length.
In this report I present the results of applying the method
to the problem of
estimating a velocity anomaly from a real data set.
The data set is particularly interesting
for testing a velocity-estimation method
because the velocity anomaly
is shorter than the cable's length and it is not located near the surface
but it is centered at a depth of about 1.5 kilometers.
Therefore both the lateral and the vertical resolution
of the estimation method are tested by the problem presented by the data.
Furthermore the pull-down in the reflections caused by the anomaly
can be corrected only
if a good velocity model is used as an input for depth migration.

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** Up:** Biondi: Velocity from beam
** Previous:** Biondi: Velocity from beam
Stanford Exploration Project

1/13/1998