| Seismic oil exploration
requires the processing of large scale
data sets. One of the main goals is
to convert the seismic data (time
histories at receivers) into depth
maps of the underground in the search
for stratigraphic oil traps and other
likely places for the precise drilling
of producing wells.
In complex geological areas the
most advanced technique is depth
reverse time migration using full
wave equation techniques. All migration
techniques are as good as the velocity
model that is used and therefore
are iterative in nature: from coarse
models to more precise ones. In
general, that requires considerable
computing time and manual interaction.
Seismic travel time ray tracing
or eikonal based tomography showed
some early promise in helping automate
the velocity improvement process
but it was dimmed to be too hard
to implement practically, because
of the need to pick interpreted
travel times from unprocessed seismic
data. In the last few years a new
set of techniques have arisen that
uses depth residuals in depth migrated
common offset sections that are
considerably easier to identify
and that can be picked automatically.
We show in this talk how to convert
a travel time tomography code into
one that can process depth residuals
and exemplify its use in some large
scale real data sets.
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