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2024-05-16

First long-term injection experiment successfully finished

First long-term injection experiment successfully finished

At the end of April, the BedrettoLab team successfully conducted their first long-term injection experiment. The experiment lasted several days aiming to generate an earthquake of about magnitude 0 and monitor it from close by.
Following a week of preliminary tests and a four-day preparation phase, high-pressure hydraulic stimulation commenced, with around-the-clock real-time monitoring. The target earthquake occurred at 6 o'clock in the morning of 30 April, somewhat earlier than expected, achieving the experiment's goal and prompting the cessation of injection.

In an earthquake of this magnitude, the rock moves along a plane by about 1-2 millimeters over an area of roughly 5-by-5 meters. This rupture lasts only a millisecond and radiates seismic waves, which our sensitive monitoring arrays are designed to capture. The waves are much too weak to be felt at the surface.
The seismology team uses these detailed recordings of such a small event to study the physical processes that occur during an earthquake. A better understanding of such processes may lead to improvements in earthquake risk mitigation and management in the future. It also contributes to better management of induced seismicity related to deep geothermal energy projects. Currently, the team is analyzing and modeling the collected data, and preparing the next long-term injection scheduled for autumn.