Simulating Hydraulic Fracture Stimulations at the EGS Collab: Model Validation from Experiments 1 and Design-Phase Simulation for Experiment 2

Abstract

The EGS Collab project focuses on intermediate scale (~10‐20 m) EGS reservoir creation processes and related model validation at crystalline rock sites. It offers a great opportunity to validate computer simulations against extensive field observations that provide definitive characterization of the outcomes of hydraulic stimulations. In each of the two sets of Collab experiments, extensive modeling was performed to support experiment design. These modeling results constituted the basis for post-experiment validations. For Experiment 1, which focused on hydraulic fracturing, design-phase modeling successfully predicted the hydraulic fracture’s strong tendency to propagate toward the drift. However, the role of rock fabric in determining fracture growth pattern was not realized until a significant discrepancy was observed in validation. The final enriched results matched well with experiment results. We also report simulation results to support Experiment 2 design, which will be validated after the experiments.