A timeline for the reconstruction of Upper Rhine Graben hydrothermal fracture mineralization events

The Upper Rhine Graben (URG) is the central part of the European Cenozoic Rift System and holds a huge geothermal potential due to a reduced Moho depth and active hot brine convection cells. In addition to that appealing potential, hydrothermal brines of the URG show high Lithium concentrations. Yet, investors-relying deep geothermal energy companies face difficulties to predict fracture network permeability before drilling operations. This problem induces techno-economic risks, which frighten investments and in turn hinder the wide development of deep geothermal energy use. The goal of this work is to provide input data to develop modelling tools to help predict fracture network permeability before drilling operations. We will integrate data from both the French and German side of the URG, which is seldomly done in studies. Here we present a timeline that we’ll use as a data compilation base to reconstruct the URG setup and hydrothermal fracture clogging history. Once identified, the fracture clogging events will be deeper characterized to be implemented in a reconstruction model. A characterization of mineralized fractures all around the URG shoulders will help to complete the list of hydrothermal clogging events identified in the Black Forest (Permian, Jurassic-Cretaceous and Paleogene) and will allow to simulate the rate of precipitation in mineralized fractures and thus their clogging potential.