Overview
- An ETH Zurich–led team injected 750 cubic metres of water into boreholes at the BedrettoLab, triggering about 8,000 tiny earthquakes in a controlled trial.
- Sensors logged local magnitudes from about -5 to -0.14, which fell short of the magnitude‑1 target and were too weak to be felt at the surface.
- Seismic activity appeared not only on the chosen fault but also on faults that cross it, showing complex fault interactions.
- Operations ran remotely with no staff in the tunnel, and the team reported no surface effects and said the added risk was about one percent of the natural level.
- Researchers will adjust injection angles and flow for a new run in June to try to reach magnitude 1 and to test how nearby faults respond.