AVO
Modeling: A Tool for the Specialist or a General Interpretation Aid?
Richard Cooper1, Lars Hübert2, Jack Dvorkin3, Jurgen Hoffmann2, Matthew Carr1,
and Alsing Selnes2
1 Rock Solid Images, Houston, TX
2 Rock Solid
Images, Oslo, Norway
3 Stanford University, Stanford, CA
Significant progress has been made in the use of AVO
inversion methods
for lithology and fluid prediction from seismic data. However,
AVO
results may
be ambiguous, and therefore not easy to interpret. Well-based forward
AVO
modeling is critical to prevent costly interpretation mistakes. However, rock
physics modeling in general, and
AVO
modeling in particular, are tasks usually
undertaken by a handful of specialists, thereby limiting the use
AVO
modeling.
Existing rock physics software and workflows are not easy to use which further
limits the widespread use of
AVO
modeling.
In this paper, we present a novel technology approach designed to move
AVO
modeling from the specialist's realm to the interpreter's realm, while
ensuring that the modeling is robust and valid. The workflow starts with the
assembly of a database of pre-processed well-log data. This step includes
petrophysical evaluation and Geophysical Well Log Analysis to ensure a
consistent and robust input dataset. A rock physics analysis is then performed
in order to determine the optimum effective medium models specific to the given
area or field (Rock Physics Diagnostics). Finally, the effective medium models
are uploaded to an easy-to-use analysis application for the interpreter to use
alongside standard seismic interpretation tools. The interpreter can now conduct
forward
AVO
modeling effectively and efficiently with robust, site specific rock
physics. The adoption of this workflow allows more rapid and reliable analysis
of
AVO
based prospects, resulting in reduced drilling risk.
AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005