A geothermal project causes the Strasbourg earthquake
People wearing face masks visit central Strasbourg, eastern France, August 5, 2020. French authorities have ordered people to wear face masks in outdoor public places in many major cities as the COVID-19 is spreading faster and admission to intensive care units increased again after a month of decline. (Photo by Geneviève Engel / Xinhua)
The city of Strasbourg, in eastern France, was rocked on Saturday by a 3.9 magnitude earthquake, the strongest to date in a series of shocks caused by a geothermal project now on hold.
The epicenter of the quake, which began at 5 a.m., was five kilometers below the surface, under the northern suburb of La Wantzenau, according to the National Seismic Monitoring Network (Renass).
A magnitude 2.3 aftershock was recorded five minutes later. Both events were classified by Renass as “induced” or caused by human activity.
While the shocks didn’t do much damage beyond creating cracks in homes, they rekindled controversy over the geothermal project, which was halted in late 2020 after a number of seismic incidents.
“It was really strong this time,” tweeted Alain Fontanel, one of the opposition leaders in Strasbourg city council. “The whole house shook for a few seconds. Thank you to the sorcerer’s apprentice of deep geothermal energy for this rude awakening.”
Fonroche Géothermie, the developer of the project, had previously acknowledged that its activities were at the origin of some of the earthquakes and clarified that Saturday’s event was also “linked to the return to equilibrium” of underground geological structures.
The project has been linked to 15 earthquakes with a magnitude of at least two since November 2019.
Local authorities ended the geothermal project in December 2020 after a series of more intense earthquakes, including one of magnitude 3.5 three days before the order.
“We have continued to see persistent seismic activity in recent months. The basement takes a while to react to shutdown [of the project], Jérôme Vergne, seismologist at the Strasbourg School and Observatory of Earth Sciences told AFP.
“What is surprising is that today we had the biggest earthquake in the streak,” he said.