A Novel Integrated Approach to Stochastic Deepwater Reservoir Modeling Using Sequence-Stratigraphic and Geomorphic Constraints

Matthew J. Pranter, Zulfiquar A. Reza, and Paul Weimer
University of Colorado, Boulder, CO

In deepwater reservoir modeling, it is important to properly represent the spatial distribution of architectural elements to account for pore-volume distribution and the connectivity of reservoir sand bodies. This is especially critical for rock and fluid-volume estimates, reservoir performance predictions, and development-well planning.

This new integrated stochastic reservoir modeling approach accounts for stratigraphic and geomorphic controls to generate the reservoir architecture and is conditioned to seismic and well data. Information on stratal-package evolution and sediment provenance can be integrated into the reservoir modeling process. A slope-area analytical approach is implemented to account for topographical constraints on channel and sheet-form reservoir architectures. A sediment source curve is simulated based on inferred paleo-channel direction statistics (from outcrop and stratigraphic studies) and simulated high-frequency eustatic sea-level curve. Based on these geomorphic and sedimentological constraints, architectural elements (channels, lobes, sheets) are built into the model sequentially (in stratigraphic order). Channel avulsion is modeled based on its dependence on sediment source and local topography. Information from detailed stratigraphic studies and other data sources is accounted for during different stages of the modeling process.

Integration of realistic geological and engineering attributes into numerical reservoir models is vital for optimal reservoir management. This approach is unique in that it is constrained more directly to geomorphic and sedimentological parameters than traditional object-based or surface-based techniques for stochastic deepwater reservoir modeling.

AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005