LUTON, LARRY C. and CORINE PRIETO , Integrated Geophysics Corp., Houston, Texas
Accurate depth conversions reduce risk is not a new concept. The
challenge lies in the proper selection of velocity data and model types
that will generate
accurate depths for the prospective area.
Velocity information is available from a number of different sources. Well
velocity
data is available from checkshots, vertical seismic profiles, sonic logs and geological
tops. Seismic imaging velocities (stacking and migration) are interpreted from various
seismic processes (2D/3D DMO, 2D/3D Prestack Time and Depth Migration).
There are many velocity model types
. They range from a single function to detailed 3D
model and can be average velocity, interval velocity, root mean square velocity or depth.
The type of model and procedure selected is influenced by available data, lithology and
geophysical acquisition and processing parameters.
Our Gulf of Mexico example will illustrate the gains in prospect resolution by using
the correct data set and the benefits to calibrating well
and imaging data sets for that
area. We will also show the refinement gained from the integration with interpretations
such as seismic derived fault interpretation and/or salt geometry from a 3D-gravity model.
AAPG Search and Discovery Article #90908©2000 GCAGS, Houston, Texas