Earthquake near St. Gallen clearly felt

The Swiss Seismological Service (SED) at the ETH Zurich has registered an earthquake with a magnitude of 3.6 at a depth of 4 kilometers in the morning of July 20, 2013, at 5:30 local time near St. Gallen. The earthquake was felt widely in the region. With an earthquake of that magnitude and depth, slight damage to buildings cannot be ruled out.

The quake is likely directly related to the tests and stimulation activities in the borehole of the planned St. Gallen geothermal project, where numerous micro-earthquakes have already occurred at the base of the borehole in recent days. In the night of July 19 to July 20, 2013, the number and magnitude of earthquakes increased significantly. An initial, slightly more powerful earthquake with a magnitude of 2.1 occurred at 2:40 local time on the morning of July 20. This earthquake was possibly felt in the immediate area in individual instances.

The seismic activity seems to be decreasing in the course of the morning of July 20; a few small additional earthquakes have been recorded since the early hours, though these have not exceeded 1.4 in magnitude. However, further quakes cannot be ruled out within the next days, according to our assessment.

The SED continues to monitor seismic activity around the clock, and will investigate the earthquakes in greater detail.