2024-09-12
The second multi-day hydraulic stimulation was finished successfully at the end of August. A team of about ten people monitored a stimulation lasting for about three days, injecting water with a pressure of 20 MPa.
As anticipated, the injection triggered a high level of microseismicity: our real-time monitoring workflow detected several thousand tiny earthquakes. The two largest events reached a magnitude of around -1.0. This is equivalent to when rocks rupture in an area of one meter in diameter and move by up to 1 millimetre.
The experiment was conducted according to a previously designed protocol. With the new remote-control system, the entire experiment and monitoring could be conducted from a control room at ETH Zurich and the Barracke near the tunnel entrance in Ronco, with no one in the tunnel.
Now, the team is busy analysing the rich data set and preparing for the next experiments in November and December 2024.