Basin modeling can be divided into two main areas: maturity modeling and migration modeling. Studies that focus entirely or primarily on maturity questions are usually carried out using 1D software. In 1D modeling, we model individual locations independently of each other. Regional studies can easily be carried out by modeling multiple locations that can include calibration wells, non-calibration wells, and pseudowells.
Migration-modeling studies, in contrast, normally utilize 2D or 3D software designed specifically for the purpose of modeling fluid flow. Migration-modeling software can in turn be divided into the traditional Darcy-flow software, which treats basins with technology based on that used in reservoir simulations, and a variety of alternatives, including invasion percolation (IP) and ray tracing.
Our philosophy is that accurate prediction of fluid-flow (migration) patterns is not usually possible because of significant uncertainties about permeability along the various possible migration pathways. Unrecognized heterogeneities in permeability create uncertainties that can range from minor in some very homogeneous settings to extremely large where non-matrix permeability is dominant over matrix permeability. The inability of basin-modeling software to predict (and thus to include properly) non-matrix permeability has been recognized for a long time (e.g., Larson et al., 1993), but has not received much attention and thus remains a major problem that can limit the confidence in migration-modeling output. We believe that a non-Darcy approach is more adaptable for modeling settings where non-matrix permeability is important.
The second key pillar of our philosophy is that the most valuable product obtained from modeling is not the calculated number of barrels of oil generated and migrated, but rather the knowledge that is acquired during the process of building and optimizing the models themselves. Since most learning occurs during construction of the 1D models (where questions about thermal history, tectonics, and reconstruction of unconformities are addressed), we emphasize 1D modeling as a stand-alone technology. In focusing on the process of building and optimizing our models more than on obtaining final output from the modeling simulations, we are emphasizing the journey rather than the destination. Finally, in the process of building these models, we focus on integrating all aspects of geology with each other: tectonics with sedimentation rates and lithologies, tectonics with heat-flow history, and paleobathymetry and paleoelevation with tectonics, eustasy, and isostasy. We believe that increasing the depth and breadth of one’s geologic understanding is the best way to generate new play concepts, refine old concepts, gain a competitive advantage, and ultimately be highly successful in petroleum exploration.
Our desire to build the best possible, fully-integrated, and consistent geologic models requires the use of software that is highly compatible with this goal. We thus use Novva, our new 1D modeling software. When we want to model migration, we use Trinity® software, because we believe it provides an effective way to model hydrocarbon flow in most geological systems.