Flagship stimulation experiment in the deep underground laboratory
Currently, medium-scale experiments are carried out at the Grimsel Test Site. The project is divided into three main phases, namely a characterization phase, a stimulation phase and a circulation phase. The characterization phase includes geophysical and geological imaging of faults and fractures, and determination of the actual stress field by means of small hydro-fracturing experiments. During the stimulation phase, fault zone will be pressurized until slip occurs, and the associated permeability creation, pore pressure propagation, deformations and seismicity will be monitored. In a second step of the stimulation phase the massive rock mass between the faults will be hydro-fractured, which allows the circulation experiments to be conducted. The characterization phase could be completed in 2015, and it is expected that the stimulation experiments will be finished by the end of 2016. The entire medium-scale experiment will be finished by the end of 2017. On the basis of the results, the following large-scale experiment will be established.
The total budget of the experiment is in the order of 6.5 Mio CHF, whereby 1.8 Mio CHF were contributed by Shell donation to ETHZ and a grant by EKZ. The remaining costs are covered through the SCCER-SoE, ETHZ and UniNe.