Abstract: An Integrated Approach to Deep-Water Reservoir Prediction

Garfield, Timothy R. & David C. Jennette - Exxon Production Research Co.; Franklin J. Goulding & Donald K. Sickafoose - Exxon Exploration Co.

Accurate pre-drill predictions of deep-water reservoir facies, architecture and producibility are fundamental to the economic success of high-cost exploration and development projects in deep-water settings. Exxon has been able to reduce these predrill uncertainties and improve its success in reservoir prediction by using an integrated approach that is collaboratively supported by business-unit, technology, and research staff. Key facets of this approach include: 1) a readily accessible proprietary data base of subsurface and outcrop analog studies, 2) experimental and numerical modeling of sediment gravity flow transport and depositional processes, 3) seismic and sequence stratigraphic analysis, and 4) 3D seismic attribute and seismic facies analysis.

Underlying the reservoir prediction effort is Exxon?s global analog database populated with exploration and production analogs from a variety of settings and a comprehensive suite of carefully studied outcrops. These data include detailed facies architecture and dimensional data for deep-water channels and sheets, well-bore measurements of reservoir properties and associated geophysical parameters. Collectively they provide a statistical basis for reservoir prediction.

Analog selection is aided by relating numerical and experimental models of sediment gravity-flow transport and depositional processes to basin-specific controls on reservoir development such as provenance, transport distance and basin physiography. These models provide an improved understanding of characteristic depositional geometries for debris flow and turbidity current deposits, which aid in the subsurface identification of these facies types.

Sequence stratigraphy provides a framework for reservoir analysis and can be used to relate inferred changes in shelfal accommodation and sediment supply to observed vertical and along-slope variations in reservoir properties. Sequence stacking patterns on the slope and basin-floor reflect periods of waxing and waining coarse clastic influx and can be used to constrain pre-drill predictions of deep-water reservoir facies and net-to-gross.

3D seismic attribute analysis performed within a tightly constrained sequence stratigraphic framework yields a detailed understanding of vertical and lateral variations in reservoir properties of genetically related strata. When fully integrated, these data are the basis for more accurate characterizations of deep-water reservoirs in the subsurface and provide new insight into the complexities of deep-water sedimentation.

AAPG Search and Discovery Article #90933©1998 ABGP/AAPG International Conference and Exhibition, Rio de Janeiro, Brazil