The crystalline basement of the Upper Rhine Graben is a major target for deep geothermal exploration due to the generally high reservoir temperatures and the increased radiogenic heat production. The geothermal potential is strongly dependent on the lithology because mainly the thermal but also the hydraulic properties are affected by the rock type. For this reason, the so far most detailed 3D model of the basement in the northern Upper Rhine Graben was developed based on existing structural models, in particular the Hesse 3D 2.0 and GeORG models. Since only a few boreholes fully penetrate the thick sediment cover, additional magnetic and gravity data provided valuable information on the geometry of the deep horizons. To interpret the Bouguer anomalies reasonably with respect to the crystalline basement, the regional gravity field and sedimentary effect were subtracted from the observed data. In comparison to the commonly applied deterministic modelling approaches, a stochastic joint inversion of the gravity and magnetic anomalies was performed that utilizes the principles of a Monte-Carlo-Markov-Chain simulation. For an appropriate attribution of the model units, existing petrophysical databases of the region have been used and in addition, the magnetic susceptibility of more than 430 rock samples was measured. High-resolution voxel models of the density and susceptibility distribution were generated as a result of the inversion, which allow conclusions about the crustal composition under the sedimentary formations. An interpretative map of the basement geology, derived from the inversion results, is presented.

由于普遍的储层温度高和放射性热产生增加，上莱茵河格拉本上层的结晶基底是深层地热勘探的主要目标。地热势在很大程度上取决于岩性，因为主要的热学性质和水力性质都受岩石类型的影响。因此，根据现有的结构模型，特别是黑森州的3D 2.0和GeORG模型，开发了迄今为止最北部的上莱茵格拉本北部地下室的最详细的3D模型。由于只有几个钻孔完全穿透了厚厚的沉积物覆盖层，因此额外的磁场和重力数据提供了有关深层地层几何形状的有价值的信息。为了对晶体基底合理地解释布格异常，从观测数据中减去区域重力场和沉积作用。与常用的确定性建模方法相比，利用蒙特卡洛-马尔可夫链模拟的原理进行了重力和磁异常的随机联合反演。为了对模型单元进行适当的归类，已使用了该地区现有的岩石物理数据库，此外，还测量了430多个岩石样品的磁化率。反演的结果是生成了密度和磁化率分布的高分辨率体素模型，这可以得出有关沉积地层下地壳组成的结论。给出了从反演结果推导出的地下室地质解释图。