This study presents the advantages of quantifying the model uncertainty for the example of the northern Upper Rhine Graben, a region known for its high geothermal potential in central Europe and its complex structural setting. In geothermal exploration, geological models are often taken as a nearly true representation of the actual subsurface. The public available models created of the northern Upper Rhine Graben are no exception to this reception. While these projects give a great insight into the geological structure, the lack of quantified uncertainty mapping limits practical use for engineering purposes. The limitation comes from the lack of quantitative knowledge, conveyed in the provided qualitative uncertainty ranges. Without a proper understanding of these ranges, exploration risks cannot be properly assessed.

This study explores the sources and impact of errors that lay ground to the structural uncertainty within a geothermal model in the northern Upper Rhine Graben. Error ranges of input data are used to establish probability distribution functions. With a custom-made stochastic workflow, using Monte Carlo simulation, maps of uncertainty are created for several formations and groups, indicating extent of uncertainty for their horizons. Furthermore, using several different sources of errors, the effects of uncertainty reduction by additional seismic and well data acquisition are explored.