Print this page ABSTRACT: A methodology to build a 3D geological model of 
reservoir
from well data
using seismic information
Anantraksakul, Nawee1, Brigitte Doligez2,
Philippe Joseph2, Patrick Pouclee3, and Jean Pouzet3
(1) PTTEP, Bangkok, Thailand
(2) IFP, Rueil Malmaison, France
(3) Total Fina, Paris La
Defense Cedex, France
New advances in geostatistical modeling allow to integrate qualitatively or
quantitatively geologic and geophysical data for a better reservoir characterization. This
is illustrated on a real field example from offshore thailand, where the reservoirs are
sand dominated amalgamated fluvial to deltaic channels.
A 3D seismic survey throughout the prospective section has been analyzed and calibrated
in order to classify selected seismic attributes in terms of probabilities of occurrence
of lithologies classes. This seismic information has been integrated as constraints in the
geostatistical simulations
of the reservoirs using the extension of the truncated gaussian
simulation method to non stationary cases. The constraint may be qualitative when the
seismic images can be interpreted and are used as a background to draw limits between
zones of different geology. The constraint may also be quantitative when a correlation
between the seismic information and the cumulated sand proportion is possible ; in that
case the seismic information is directly used in the kriging system for the local
estimation of sand proportions. Several tests are presented, using different hypotheses
and different types of seismic constraints to illustrate their impact on the final results
in terms of net sand maps of the simulated reservoirs and of final estimation of the oil
and gas volumes in place.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia