Print this pageAbstract: A Case History on 3D Seismic Imaging in Hydrocarbon Exploration and Production
COLE, R.C., J.C.
DEKNATEL, S.M. DEVRIES, R. EAST, 
P.P.
GELDERBLOM, P. GERRITSMA, D.J. SMIT,
M. VANDERVEEN
Decision making in
hydrocarbon exploration and production depends critically on a sharp and
correct image of the subsurface. The most powerful technique with which
seismic data can be processed in order to obtain such an image is 3D pre-stack
depth migration. This technique is nowadays routinely used by many operating
units of Shell.
Despite the use of this technique,
the image is often vague and incorrect in areas with very complex subsurfaces,
for example the presence of overthrusts or saltdomes. Especially in these
areas the quality of the image can be enhanced when all the geological
information is used together with data from (physically) different types
of measurements. To sharpen such an image the seismic data processing can
benefit from well data (where sonic logs provide velocity information and
the depth of key horizons is known) and/or from gravity measurements (which
have a higher lateral resolution than seismic data). Uncertainties can
even be further reduced if the seismic processing carefully takes into
account the effects of elastic wave conversion (longitudinal waves convert
to transverse waves, and vice versa, when they hit a geological layer with
different elastic properties).
The case history that will
be presented shows the effect of the integration of these various techniques
and data
sets on the imaging of a complex salt dome. The level of confidence
in the interpretation of the image of the subsurface is increased significantly,
once all sources of information are integrated.
AAPG Search and Discovery Article #90942©1997 AAPG International Conference and Exhibition, Vienna, Austria