The subsurface of the Aachen-Weisweiler area with its Carboniferous and Devonian carbonates is a green-field target location for testing and developing deep geothermal energy systems in North Rhine-Westphalia, Germany. Despite subsurface mining, surface mapping and isolated deep exploration wells and crustal seismic data, only sparse information on the deeper structures (down to 4,000 m), the spatial distribution of the reservoirs and reservoir properties has so far been recorded and/or published. Therefore, the complex structures of the faulted and folded Paleozoic layers remain unknown requiring further investigations. With the “Field Scale Laboratory for Deep Geothermal Energy Rhineland”, we aim to characterize the subsurface of the Aachen-Weisweiler area including its structural uncertainties, to quantify the reservoir properties of the carbonates and their associated parametric uncertainties to better describe the geological risk in exploring the reservoirs. Firstly, we constrain a geological model based on the publicly available surface and subsurface data and quantify its structural uncertainties. The model and the uncertainties are revised after the integration of vintage and newly acquired seismic data. Planned deep exploration wells will provide further constraints for the structural model but also deliver in-situ measurements of reservoir properties and geomechanical properties for subsequent thermo-hydraulic-mechanical modeling. The investigations contribute to the characterization of the potential geothermal reservoirs in this region, aid in the exploitation of the reservoirs, finding drilling locations for wells, and expand geological knowledge of the carbonates from other regions into Germany, hence, de-risking the geothermal plays in the Aachen-Weisweiler area.