Local Grid Refinement Methods for Basin Modeling
Local grid refinement (LGR) is applied in reservoir simulation routinely for structured and unstructured grids and implemented in commercial simulators. It is used to add detail where justified by data availability and to keep a coarse resolution where less data are available.
In basin modelling, LGR has not yet been implemented. It could be used in situations where seismic data are available at individual structures or prospects but not elsewhere in kitchen areas or within the sedimentary cover. Even more importantly, for appraisal studies, a data set may be available at reservoir resolution that may have to be integrated with the basin scale to model the impact of basin scale fluid flow on the reservoir.
Presently, tartan grids allow to refine the grid in x,y directions but waste a lot of grid cells in areas where refinement is neither necessary nor wanted. Vertical grid refinement is performed where the stratigraphic grid needs to be enriched to model fluid flow. In order to better represent data availability (basin versus prospect/structure of interest) and to save computing time, it is preferable to have a lateral and vertical grid refinement that only treats areas where information is available
The BasinLGR project has developed numerical methods that allow to treat two or more imbricated Cartesian grids refining in all three spatial directions with several levels of refinement. Fluid flow is performed on refined grid while thermics remain on the coarse grid.
Full Basin 4-D Modeling
2004 AAPG International Conference and Exhibition Technical Program