Excerpt:
Continental rifts hold immense potential for renewable geothermal energy, addressing the urgent challenge to transition from high-carbon to low-carbon energy sources. Here, we combine long-term geodynamic modelling with shorter-term reservoir rock mechanics modelling to evaluate the geothermal potential within the complex geological setting of the Upper Rhine Graben, France-Germany.

Summary:
Climate change has accelerated the shift towards alternative, environmentally friendly, and renewable energy sources to reduce global reliance on fossil fuels. Among these, geothermal energy stands out as a promising solution due to its independence from external environmental factors, low carbon footprint, and versatility in providing both baseload electricity and district heating. The Upper Rhine Graben (URG), situated along the border of France and Germany, is part of the intraplate European Cenozoic Rift System. The graben is widely recognized for its abundant geothermal resources, making it a key region for energy transition initiatives. However, the characterization of the URG’s geothermal potential remains poorly constrained due to its highly variable hydrothermal conditions and large observational gaps. Previous studies on fault criticality have often overlooked the role of historical plate movements, oversimplifying the intricate interactions that govern the thermal and structural evolution of the URG over the past ~40 million years.

This study explores how tectonics in different temporal and spatial scales influence the geothermal potential within a rift system. Using the numerical geodynamic code ASPECT coupled with the landscape evolution code FastScape, we simulate the lithospheric-scale development of fault networks within the URG under geodynamically realistic stress and strain conditions. An automated coupling mechanism will be implemented between ASPECT and the thermo-hydro-mechanical code GOLEM, integrating long-term basin geodynamic development with shorter-term heat and fluid flow simulations that involve rock and fracture mechanics. This multi-scale modelling approach is our attempt to improve the accuracy of geothermal drilling target identification. Throughout all modelling stages, we compare our models with available geological and geophysical observations.