| Abstract |
Several geothermal power plants are planned for one of the most promising regions in Germany, the Upper Rhine Graben (URG). Induced seismicity can have a strong impact on the viability of such projects. For instance at the Basel/Switzerland Deep Heat Mining site, located at the southern end of the URG, after massive hydraulic fracturing in 2006/2007 several earthquakes with magnitudes of up to 3.4 occurred. An expert report on this seismicity has led to a final stop of the project. To prevent other geothermal projects from this fate a prognostic of possible induced seismicity and measures to limit the maximum magnitude are currently one of the most important geothermal research topics. Based on a geometric GOCAD model of the German federal state Hessen, covering the northern part of the URG, a large scale heat transport model was developed. For regions where geothermal exploration is planned, coupled thermo-hydro-mechanical (THM) models can be computed. The THM modelling is based on a FEFLOW model for the thermo-hydro coupling together with a plug-in for the (linear elastic) mechanical coupling. The approach is demonstrated exemplarily for a site, using literature data |