Usage Of Multiple Simulation Grids For Basin Modeling
Publication Date: 2013-Jan-23
The IP.com Prior Art Database
Usage of multiple simulation grids for Basin Modeling
Basin modeling usually comprises of a variety of different modeling parts: Starting from the reconstruction of geometries at paleotimes, (de)compaction of the rock matrix, pore pressure prediction, temperature analysis, and geomechanics.
The time-evolution of the geological relevant processes in a sedimentary basin is commonly described by a set of coupled partial differential equations (PDE), e.g. a heat-flow equation for the temperature analysis and a pore-water flow equation for the pore pressure prediction. The resulting set of equations is typically too complex to be handled analytically, so one usually relies on a numerical analysis. Rock properties like porosity, permeability or thermal conductivity are taken as constant within small parts of the basin, i.e. grid cells. By using this discretization of the problem combined with a finite element analysis, it is now possible to solve these partial differential equations on a computer. The numerical effort depends on the total number of cells used, i.e. when the number of cells is increased (and hence the spatial accuracy of the simulation) the computational costs are increasing as well. It is obvious that the number of cells needed to faithfully represent a sedimentary basin is strongly related to the homogeneity of the model. When a homogenous model with only minor spatial variations of the rock properties is considered, typically only a small number of cells is required. On the other hand, for a model with strong inhomogeneities this number has to be increased.
Modern basin simulators can handle models up to a size of a few hundred million cells. Limiting factors are restricted computation times and resources, however, it is highly desired to further enhance the spatial simulation accuracy, i.e. to increase the number of cells of the basin model.
Summary of the Invention
Anew gridding concept is considered which significantly improves the performance of basin simulators, hence enabling the user to create and simulate basin models with a higher accuracy than with prior art technology. The idea of this invention is simple: instead of using the same grid for all basin modeling processes, one could use different grids for different processes. This allows the simulator to focus the computational resources on (geo)physical processes where a high resolution is involved, while for other processes for which a high resolution is not involved, the computational costs can be reduced significantly.
Detailed Description of the Invention Including Examples and Drawings
As discussed in the introduction, the number of cells needed to faithfully simulate a basin model depends on the homogeneity of the model. The level of homogeneity can vary dramatically when considering different (geo)physical processes.
Let us start with considering the pore press...