A M4.6 earthquake hit central Switzerland on Monday night, March 6, 2017. This is the strongest quake to hit the country within the last 12 years.
While no damage was reported, police in the cantons of Bern, Aargau, Zurich and Graubünden received dozens of calls from worried residents who felt the quake.
The quake struck at 9.12pm at a depth of 5km under the summit of the Ortstock mountain in the canton of Glarus, around 6km west of the town of Linthal.
So many people visited the SED’s website after the earthquake that it crashed.
Statistically earthquakes of this size happen once every few years in Switzerland.
About a dozen aftershocks were detected after the main event, with more to be expected in the coming days. It is however unlikely that there will be an earthquake with a similar or even larger magnitude than the main shock but this cannot be excluded.
The last quake of a similar magnitude occurred just over the French border in Vallorcine in 2005 but was felt widely in the Swiss canton of Valais. Last year’s biggest quake was a M4.1 near Leukerbad in the Valais in October.
Around ten quakes of between 3 and 4 magnitude hit the country every year, with a 4+ quake expected every 1-3 years. Strong earthquakes, classified of 6 magnitude or above, occur once every 50-150 years. The last, a 6.2, hit Sierre in 1946, meaning Switzerland is due another large one by around 2040.
Switzerland experienced 880 earthquakes in 2016, slightly more than the 40-year average, but such variations are normal say officials!