An epicentre is the vertical projection of a hypocentre (seismic focus) on the earth's surface (the place located directly above a hypocentre), generally specified in terms of its geographic coordinates (longitude and latitude).

The values along the Richter scale correspond to the strength of an earthquake, referred to as its 'magnitude'. The scale was developed by American scientist Charles F. Richter in 1935. Even today, the size of an earthquake in Switzerland is usually expressed in units on the Richter scale (M_Lhc local magnitude). However, as time passed it became apparent that the Richter scale is only suitable for measuring earthquakes within a given range of magnitudes and distances. For this reason, other magnitude scales were developed.

Earthquakes of intensities ranging from VI to VII can potentially damage the types of buildings generally constructed in Switzerland. This corresponds roughly to a magnitude of 5.

Destructive damage can be expected above an intensity of IX or a magnitude of around 6.

Close to the epicentre, some earthquakes above a magnitude of 2.5 can already be felt.

The impacts of an earthquake on the earth's surface (i.e. on buildings, people, the environment and infrastructure) are described using a 12-point intensity scale.

The intensity of an earthquake depends on its location and is determined by its magnitude, the distance from the earthquake epicentre and the geology (subsurface).

One way the Swiss Seismological Service (SED) ascertains how and where earthquakes are felt is by means of an online questionnaire that the public can fill in.

No, for decades now scientists have been looking for reliable warning signs of an impending earthquake, but so far their search has been in vain. Perhaps earthquakes are natural hazards, chaotic, non-linear processes that we will never be able to reliably predict. Or maybe scientists will find a hot lead yet. Only time will tell!

However, something we can calculate is the earthquake (or seismic) hazard and risk. Earthquake hazard indicates where and how frequently over a set time period certain shaking can be expected to occur. Earthquake risk quantifies the possible effects of earthquakes on buildings and the associated financial and human losses.

Although the terms are often mistakenly used as synonyms, they have different meanings. Therefore, always be careful when using these two terms:

While earthquake hazard estimates how often and how strongly the ground could shake at given locations in the future, earthquake risk quantifies the possible effects of earthquakes on buildings and the associated financial and human losses.

Before a strong earthquake

Buildings should be built to withstand earthquakes. Any items that could fall down should be  secured.

During a strong earthquake
If inside a building, you should seek cover, move away from any windows and shelves, and wait until the environment is safe.

If outside or in a vehicle, you should stay a safe distance from buildings, bridges, trees, pylons and tunnels. Stop the vehicle and do not leave it during the quake.

After a strong earthquake

You should brace yourself for aftershocks and use the radio, television and internet to stay informed.

Induced earthquakes are earthquakes triggered by human activity. In Switzerland, man-made quakes occur are mainly in connection with related to geothermal energy projects. However, earthquakes can also be triggered by other underground activities. For example when injecting CO₂ or wastewater into the subsurface in the context of conventional or unconventional extraction of crude oil or gas through fracking or in mining or tunnel construction. Furthermore, man-made alterations to the earth’s surface can also trigger earthquakes, for example when filling or draining reservoirs with water.