Print this pageBeyond Structure: 
Geophysics
for Reservoir Management
(Lithology, Fluids, and Fluid Movement)
PENNINGTON, WAYNE D.
It has always been recognized that there is more information in a typical
geophysical survey than simply structure of the subsurface. Recent advances in
geophysics and related fields have moved the industry toward an ability to
predict rock types and fluid saturants and their temporal changes. This has
freed the geophysicist from conventioin: instead of simply presenting a
structural map to a geologist for interpretation, the geophysicist is now (or
should be!) a part of a team including geologists and engineers, refining the
interior of the volume described by the structural maps. The successful
geophysicist may be an integral part of a reservoir management team, helping to
site development wells and providing detailed input to reservoir simulators.
This geophysicist also draws on many areas of expertise including wellbore
measurements, laboratory studies, scaling relationships, engineering properties
of fluids, and rock mechanics.
Three advances were required to occur in order to take advantage of
geophysics for reservoir management: improved geophysical imaging; new wellbore
measurements; and improved theories of rock physics.
The possibility of reducing ambiguity in seismic interpretation has led to
the introduction
of a new term: Seismic Petrophysics, defined here as the
careful and purposeful use of rock physics data and theory in the interpretation
of seismic observations. In order to make the fullest use of seismic
petrophysics, we need to (a) develop appropriate-use scenarios for the
geophysical tools and theories, and (b) develop appropriate easy-to-use and
understand techniques and services. Education, or technology transfer, will be a
key to this advance, as will field testing of some of the competing tools and
theories.