Geophysical Characterization of the Gross Schoenebeck Low Enthalpy Geothermal Reservoir

Abstract The EU funded project I-GET is aimed at developing an innovative strategy for geophysical exploration of geothermal deep water systems. The strategy is to integrate all the available knowledge, from rock physics to seismic and magnetotelluric (MT) deep sounding. The magnetotelluric method is a natural-source electromagnetic method capable of imaging the subsurface electrical conductivity down to depths of several kilometers. Since electrical conductivity depends strongly on the presence of fluids, the magnetotelluric method is a very promising exploration technique for geothermal reservoirs. In this work we present results of MT experiments carried out in the study area which is located approximately 20 km north of Berlin. The MT data was collected along a 40 km-long profile centered on the well doublet and a second 20 km-long profile located 5 km to the east. The 2D inversion results show a good correlation of the resistivity model with tectonic structures. Several zones of high conductivity coincide with structural lows, probably due to sedimentation of more porous material or fluid accumulation. Two distinct conductors located at depths of 4-5 km could be related to a deep, highly fractured anhydrite zone.