Researchers in southern Switzerland successfully triggered thousands of tiny earthquakes in a monitored setting, seeking to discover seismicity insights that could reduce risks.
Lead researcher Domenico Giardini explained that the goal was 'to understand what happens at depth when the Earth moves.'
The experiment, dubbed Fault Activation and Earthquake Rupture (FEAR-2), involved injecting 750 cubic meters of water into boreholes drilled into the tunnel's rock walls, aiming to provoke a magnitude-1 earthquake.
During the experiment, no people were in the tunnel for safety reasons, with everything managed remotely from the ETH Zurich lab in northern Switzerland.
In the end, some 8,000 small seismic events were induced along the targeted fault, but also along other faults running perpendicular to the main one, sparking local magnitudes ranging from -5 to -0.14.
The findings will help determine the best injection angles for reaching magnitude 1 at the BedrettoLab when researchers next give it a try in June.
Giardini stressed that the experiment was completely 'safe' and added only 'about one percent of what is the natural risk.'
