WBGeo: An Automated Framework for Geosystem Modeling with Advanced Mesh Generation Capabilities

WBGeo (WorkBench for Digital Geosystems) aims at automating the workflow from geological data integration to structural modeling, mesh generation, numerical simulation, and visualization. The framework is designed as a collaborative project, enabling the systematic and reproducible development of geoscientific models while reducing manual intervention across the entire modeling pipeline.

One of the core components of WBGeo is the generation of computational meshes tailored to complex geoscientific workflows. The framework supports three mesh representations: implicit structured meshes, explicit structured meshes, and explicit unstructured meshes. This flexible design allows users to select an appropriate meshing strategy based on model complexity, data availability, and computational requirements.

Implicit structured meshes are generated from volumetric structural models in which lithological information is defined on a regular grid. The meshing procedure operates directly on the implicit representation of the structural geological model and produces a structured hexahedral mesh suitable for numerical simulations based on finite element or finite volume/difference methods.

For explicit structured meshes, vertices are first extracted directly from the geological surfaces as provided by the structural model. Each geological layer is first discretized using a uniform, user-defined number of interpolated points to ensure consistent lateral resolution across all layers. Subsequently, vertical refinement between adjacent layers is performed using a user-defined number of subdivisions, allowing controlled resolution along the depth direction. To preserve mesh quality and avoid numerical instabilities, the minimum vertical distance between corresponding points in adjacent layers is evaluated using a user-defined threshold. If this distance falls below the specified limit, one of the points is adjusted vertically by a predefined amount to enforce the minimum separation. Following this correction step, hexahedral elements are constructed, resulting in a structured mesh suitable for efficient numerical simulations.

For explicit unstructured meshes, vertices are obtained directly from the structural model geometry. The surfaces are then interpolated and discretized, and the resulting geometry is passed to the Gmsh Python API for mesh generation. After determining intersections between surfaces and performing geometric fragmentation, tetrahedral elements are generated. One of the main components of unstructured meshes in the workflow is the inclusion of fault planes, and engineering objects such as wells, mining shafts, point sources, or additional internal planes, which are difficult to represent within a structured mesh framework.

By supporting both structured and unstructured meshing strategies within a unified workflow, WBGeo enables users to balance computational efficiency and geometric complexity while maintaining reproducibility and consistency across geosystem modeling applications. The generated meshes can be exported to different formats such as exodus, abaqus, feflow to be used by different commercial and open-source simulation packages.