Researchers Generate Earthquakes in the Alps

An earthquake to better understand earthquakes: Researchers have triggered an artificial earthquake in the Alps. Researchers from RWTH Aachen, ETH Zurich, and the Italian Instituto Nazionale di Geofisica e Vulcanologia (INGV) in Rome were involved in the project. The goal of the experiment is to better predict earthquakes in the future.

The earthquake was triggered in the BedrettoLab, a tunnel under the Gotthard Massif in the Swiss canton of Ticino. There, researchers attached hundreds of sensors, such as tiltmeters and strain gauges, to so-called faults – these are zones of weakness in the rock where earthquakes can be triggered. The sensors are so sensitive that they registered a major earthquake that occurred off the northeast coast of Japan on April 20.

To trigger the quake, water was injected into the fault zone under high pressure. This caused “an entire cascade of smaller earthquakes,” RWTH announced. “The experiment was very successful,” summarizes Florian Amann, one of the leaders of the project called Fault Activation and Earthquake Rupture (Fear).

Important insight into earthquake physics

With their sensors, the team was able to gain important insight into earthquake physics. It is important to better understand what happens before a quake. A major earthquake is the result of thousands of small quakes that develop.

“There is a lot of information contained in this development,” explains Amann. The numerous microquakes make it possible to trace where stresses have built up and dissipated and where stresses have led to the shearing of part of the fault zone.

According to the researchers, the quake had a “magnitude just below zero” and was not perceptible on the surface. However, this is not relevant for the research work: “A major, violent earthquake is not physically much different from a small earthquake,” explains Amann. Advantage of the operation: Normally, earthquakes are detected by sensors located on the Earth's surface, often far away. Within the Fear project, the team was able to capture data directly at the origin of an earthquake.

The BedrettoLab is a decommissioned, 5.2-kilometer-long tunnel under the 3192-meter-high Pizzo Rotondo. ETH Zurich converted it into an underground laboratory. Research is conducted there not only on earthquakes but also on geothermal energy.

(wpl)