Advances in 3D earth modelling

3D earth modeling provides a critical foundation for much of the applied geosciences, including groundwater modeling. Objectives of groundwater modeling include meaningful interpretations of fluid flow, aquifer characteristics, contaminant transport, and other factors important to decision making. Modern 3D earth modeling systems are capable of providing the complex stratigraphic, folded, faulted, and fractured frameworks necessary for the most advanced fluid flow modeling. They are also capable of providing a powerful framework for interpreting the results, including data-constrained, quantitative assessments of uncertainty and risk. Such applications are demanding in terms of a visual and computational software environment, requiring the capability of multi-disciplinary 3D spatial modeling of complex geology. The values and uncertainty of many irregularly sampled, spatial rock-property variables must be consistently managed. The critical requirements of 3D modeling in this context are rapid transformation between 3D vector (wireframe) and raster (grid) models, the capability to simultaneously manage an arbitrarily large number of spatial variables on any model object, modeling of structural geological (volumetric) uncertainty, and modeling the uncertainty of spatial variables that are both continuous (e.g. porosity) and categorical (e.g. facies). Models must be built relatively rapidly and be convenient to edit as new data arise. Query capabilities are necessary to provide users with a dynamic interaction with the model, particularly the ability to quickly highlight spatial volumes in which a number of criteria are satisfied. Advanced 3D visualisation of the model and its variables is important for interpretation.