Deep beneath Swiss Alps, researchers trigger 8,000 tiny quakes in controlled test

Researchers have made the ground shake in southern Switzerland, triggering thousands of tiny earthquakes in a monitored setting, as they seek to discover seismicity insights that could reduce risks. "It was a success!" said Domenico Giardini, one of the lead researchers on the project, as he inspected a crack in the rock wall lining a narrow tunnel far below the Swiss Alps.

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Reached by specially adapted electric vehicles that slide through the dank darkness along concrete slabs laid over a muddy dirt floor, the deep underground laboratory is the ideal location to create and study earthquakes, Giardini said. "It is perfect, because we have a kilometer and a half of mountain on top of us... and we can look very close at the faults, how they move, when they move, and we can make them move ourselves," he told AFP.

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During the experiment, no people were in the tunnel for safety reasons, with everything managed remotely from the ETH Zurich lab in northern Switzerland. When AFP visited the Zurich lab a day into the experiment, scientists were excitedly discussing the first signs of seismicity on the monitors.

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In the end, some 8,000 small seismic events were induced along the targeted fault, but also, surprisingly, along other faults running perpendicular to the main one, sparking local magnitudes ranging from -5 to -0.14. "We did not reach the target magnitude that we had set, but we reached just below," Giardini said. That alone was a huge success, he insisted, pointing out that although there had been previous efforts to create tiny earthquakes in lab settings, it was "never at this scale and never this deep."