# Earthquakes: noticeable events, magnitude 2.5+, since 1975 A thematic map of the Atlas of Switzerland, the national atlas published by ETH Zurich. The map is drawn in the browser; this file describes it and lists its variants and links, but not the data values shown on the map. - Map: https://atlasderschweiz.ch/en/theme/earthquakes-noticeable-events-magnitude-2-5-since-1975/ - Short title: Earthquakes: noticeable events - Map id: 437 - Categories: Nature and Environment › Geology and raw materials › Earthquakes - Keywords: Geology, Seismic activity - Published: 2017-04-25 - Last revised: 2023-01-17 - Content language: English - Other languages: [Deutsch](https://atlasderschweiz.ch/de/thema/erdbeben-spuerbare-ereignisse-mit-magnituden-2-5-seit-1975.md), [Français](https://atlasderschweiz.ch/fr/theme/seismes-tremblements-perceptibles-au-moins-magitude-2-5-depuis-1975.md), [Italiano](https://atlasderschweiz.ch/it/tema/terremoti-eventi-avvertibili-magnitudo-2-5-dal-1975.md) ## Description Earthquakes are caused by a sudden release of stress along faults in the earth's crust. The continuous motion of tectonic plates causes a steady build-up of pressure in the rock strata on both sides of a fault until the stress is sufficiently great that it is released in a sudden, jerky movement. The resulting waves of seismic energy propagate through the ground and over its surface, causing the shaking we perceive as earthquakes.Generally, earthquakes occurring in Switzerland results from collisions between the European and the African lithospheric plates. Induced quakes are caused by human activity, like tunnel construction, filling reservoirs and implementing geothermal or fracking projects. Intensity: Measure of earthquake size in terms of the observed effects at the Earth's surface. In Europe earthquake intensities are classified from I to XII according to the European Macroseismic Scale (EMS-98), previously also known as the Mercalli Scale. (Examples: light structural damage = intensity VI; heavy structural damage = intensity VIII.) *Magnitude:* Measure of earthquake size in terms of the energy released at the source. It is calculated from the amplitude of the instrumentally measured ground motion (seismograms). Magnitudes are calculated by a variety of different methods that result in slightly different values. However, ultimately they are all related to the well-known Richter Scale. The magnitudes given here correspond to the so-called moment-magnitude. Using its digital monitoring network, on average the Swiss Seismological Service (SED) registers two earthquakes a day in Switzerland and neighboring countries, making a total of between 500 and 800 quakes a year. Usually, around 10 to 15 of these events are strong enough (i.e. have a magnitude of 2.5 or above) to be felt by the local population.In principle, near the epicenter, earthquakes with a magnitude of 2.5 or above can be felt. Only rarely do we receive earthquake notifications for events with a magnitude of just under 2. Earthquakes with magnitudes of 3 or higher are felt by large numbers of people; at magnitudes of between 4 and 5 they can be felt within a radius of up to 200 kilometers; and at magnitudes of 5 or more they can be felt up to several hundred kilometers away under some circumstances. ## Sources - Swiss Seismological Service: [Earthquake Country Switzerland](http://www.seismo.ethz.ch/de/knowledge/earthquake-country-switzerland/) ## Data sources - SSS (2016): [Earthquake catalog ECOS-09](http://ecos09.seismo.ethz.ch/index.html) - SSS (2023): [Earthquake Catalog of Switzerland, ECOS](http://www.seismo.ethz.ch/) ## Data owners - [Swiss Seismological Service (SED)](http://www.seismo.ethz.ch/) ## Citation The terms of use ask to name the Atlas of Switzerland and the data owners, and to keep the source references in exports, screenshots and embeds. Cite the map as: > Atlas of Switzerland (2023): Earthquakes: noticeable events, magnitude 2.5+, since 1975. ETH Zürich. Map data © SED. https://atlasderschweiz.ch/en/theme/earthquakes-noticeable-events-magnitude-2-5-since-1975/ ## Variants The map has 6 variants. Levels: variant → time. The `u` value of a variant selects it in the links below. - Overview - Earthquakes since 1975: `u=A8QAAABz` (default) - Detail - 1975-1985: `u=A8oAAAB0` - 1986-1995: `u=A8kAAAB0` - 1996-2005: `u=A8gAAAB0` - 2006-2015: `u=A8cAAAB0` - since 2016: `u=A8YAAAB0` ## Links Replace `{u}` with the `u` value of a variant above, or leave out `u={u}` for the default variant. The map opens at its full extent; a link cannot set the map position. - Map: https://atlasderschweiz.ch/en/theme/earthquakes-noticeable-events-magnitude-2-5-since-1975/?u={u} - Short link, stays valid when the title changes: https://atlasderschweiz.ch/en/t/437/?u={u} - Side by side with another map: https://atlasderschweiz.ch/en/comparison/?lt=437&lu={u}&rt={id of the other map}&ru={u of the other map, or leave out} Embed in another website (allowed by the terms of use, as long as the source references stay visible): ```html ``` In the embed URL, `dm` sets what is shown: `e` the map with its title bar (default), `p` also the values of an object clicked on the map, `m` only the map with a button that opens it in the atlas. `ig=1` (default) lets the map react to scrolling and dragging only after a click into it, `ig=0` right away. The size can be changed in `style`. For the use and citation of maps and data, see the [terms of use](https://atlasderschweiz.ch/en/terms-of-use/).