A methodological framework to assess the sensitivity and resolution of geophysical methods for deep fractured geothermal reservoirs in the Upper Rhine Graben

Deep geothermal exploration in the Upper Rhine Graben (URG) relies on geophysical imaging of deep fracture systems, fault zones and associated fluid pathways. Two end-member geothermal targets are commonly considered: Soultz-type (fractured crystalline basement) and Rittershoffen-type (major fault at the sediment to-basement interface). Motivation: In practice, geophysical methods involve trade-offs between imaging resolution, sensitivity to structural vs fluid-related contrasts, depth of investigation and operational cost. However, no target-oriented framework currently links geother mal target definition, acquisition design and expected geophysical response prior to survey implementation. Objective: Develop a structured methodological framework to evaluate which meth ods and acquisition configurations best constrain structural and fluid-related con trasts for deep fractured geothermal targets in the URG Methodological approach: The framework integrates geological and petrophysical priors into geo physical forward modelling simulations to assess method sensitivity and achievable resolution for rep resentative URG targets. Synthetic tests and benchmarking are performed under alternative acquisition configurations (airborne, grounded, downhole, or combination of both) before validation against real datasets.