Understanding controls on temperature anomalies in the Wörth area of the Upper Rhine Graben by integrating static and dynamic data at the regional scales

The Upper Rhine Graben (URG), located in southwestern Germany, is well-known for its exceptional geothermal potential. As part of the European Cenozoic Rift System, it is characterized by complex fault-fracture networks that facilitate deep fluid flow leading to zones of pronounced heat anomaly, with geothermal gradients up to 100 °C/km. The geothermal site Wörth am Rhein of URG is an important target for deep geothermal energy production due to its high subsurface temperatures (> 160 °C) in the sedimentary aquifers as Muschelkalk and/or Buntsandstein, which can be used for industrial heating purposes. This type of geothermal play system is catalogued as non-magmatic, convection-dominated, fault-controlled. Recently published work suggests that the URG is characterized by large confined convection cells associated with hydraulically active fault zones.

Therefore, it is of paramount importance to understand, on a regional scale, the main factors and mechanisms that control the distribution of the thermal field in this type of geothermal play. Hence, in order to minimize the associated exploration risks, it is necessary to develop 2D/3D thermal-hydraulic (TH) models on a regional scale that combine existing static and dynamic data with robust numerical modeling following a stepwise complication approach. This integrated procedure provides valuable insights into the geothermal potential of the Wörth area and provides a framework for similar studies in other geothermal regions with similar geological settings. The results of this work contribute to the development of more efficient and sustainable geothermal energy development strategies and support the transition to renewable energy sources.