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Swiss Seismological Service (SED)

The Swiss Seismological Service (SED) at ETH Zurich is the federal agency for earthquakes. Its activities are integrated in the federal action plan for earthquake precaution.

Felt Earthquakes in Switzerland

Local Time
Mag.
Location
Felt?

No earthquakes felt in Switzerland within the last 30 days.

Latest Earthquakes

Local Time
Magnitude
Location
2019-05-24 18:29 1.5 Sarnen OW
2019-05-24 16:28 1.4 Chamonix F
2019-05-24 12:09 1.0 Bulle FR
2019-05-24 11:54 0.3 Saxon VS
2019-05-24 03:18 1.7 CHAMPERY VS
2019-05-23 11:59 1.0 Saas Fee VS

Swiss Earthquakes Counter

since 01.01.2019 
000

Recent earthquakes magnitude 4.5 or greater

Time (UTC)
Mag.
Region
2019-05-24 22:34:05 4.5 Eastern Caucasus
2019-05-21 08:58:20 4.7 Southern Greece
2019-05-15 16:53:46 4.8 Eastern Mediterranean Sea
2019-05-15 10:54:43 4.6 Southern Greece
2019-05-14 15:07:55 4.5 Ionian Sea
2019-05-13 21:27:32 4.5 Southern Greece
2019-05-13 16:57:16 4.9 Southern Greece
2019-05-13 15:31:25 4.5 SOUTHERN GREECE
2019-05-11 10:28:59 5.3 IRAN-IRAQ BORDER REGION
2019-04-29 18:02:43 4.6 Turkey
2019-04-29 04:43:17 4.8 Dodecanese Islands, Greece
2019-04-25 11:04:25 4.5 Southern Greece
2019-04-23 08:58:14 4.5 Albania

Recent earthquakes magnitude 6 or greater

UTC Time
Magnitude
Location
2019-05-23 08:45:18 6.1 Andreanof Islands, Aleutian Islands, United States
2019-05-19 14:56:50 6.2 Southeast of Loyalty Islands
2019-05-19 01:24:08 6.0 Vanuatu Islands
2019-05-19 01:23:29 6.3 Southeast of Loyalty Islands
2019-05-14 12:58:26 7.5 New Britain, Papua New Guinea, region
2019-05-12 19:24:50 6.1 Panama-Costa Rica border region
2019-05-09 23:48:42 6.1 Kyushu, Japan
2019-05-06 21:19:37 7.1 Eastern New Guinea, Papua New Guinea, region
NEWS

2019-05-24

Earthquakes and geothermal energy: lessons from Pohang

Earthquakes and geothermal energy: lessons from Pohang

In November 2017, a magnitude 5.5 earthquake shook the South Korean city of Pohang, injuring over 100 people and causing $300 million worth of damage. Just a short time later, suspicion arose that the quake might have been triggered by a nearby geothermal project. This impression was backed up by two scientific studies, one of which was written by employees of the Swiss Seismological Service (SED) at ETH Zurich (see the news article dated 26/04/2018). As a result, the South Korean government set up an international expert commission, whose members include Professor Domenico Giardini from ETH Zurich. This commission's recently published final report confirms that the geothermal project was indeed the cause of that highly destructive earthquake.

The commission examined the tectonic stress conditions, local geology, induced seismicity, drill data and details of the hydraulic stimulations associated with the geothermal project in Pohang, which was intended to construct a heat exchanger 4-5 km down in the crystalline bedrock. A similar petrothermal geothermal energy project was also attempted in Basel in 2006. Projects like this entail pumping fluid into the ground under high pressure. As expected, this triggers numerous minor quakes. Unnoticed by the operators, these injections in Pohang repeatedly set off earthquakes in quite a large previously unknown fault zone. This weakened the apparently tectonically pre-stressed fault line, leading to the magnitude 5.5 earthquake. Now that the causal link has been proved, the expert commission is asking what lessons can be learnt from the occurrence.

Its verdict on the project is far from positive. Indeed, looking back it can pinpoint failings at all stages of the undertaking. Before work began, geological studies had shown that some fractures were critically pre-stressed. Bearing in mind the proximity to a medium-sized city with a major industrial port, this finding should have prompted an adjustment of the project's risk assessment. Then the first hydraulic stimulations began at borehole PX-2. The geological reports state that large quantities of the fluid pumped into PX-2 seeped away. This is unusual, constituting another alarm signal, an indication that the borehole ran through a sizeable interference zone. Locally, the spillage of the injected fluid increased the pressure on the fault zone and already triggered numerous small earthquakes early on. Yet this increased induced seismicity was only analysed after the magnitude 5.5 earthquake.

The commission also looks into the two-month period between the last hydraulic stimulations and the damaging quake. This time lag has repeatedly been interpreted as indicative of no connection between the geothermal project and the earthquake. However, the report invokes findings from other projects which prove that induced seismicity often does not stop when hydraulic stimulations come to an end. The commission recommends involving the respective authorities and all relevant experts in the run-up to future projects, to draw up a comprehensive risk analysis and then keep it constantly updated. Furthermore, a reliable real-time monitoring system has to be set up, the processes and injection strategy must be constantly reviewed and, if need be, corrected, and risk mitigation measures need to be formally noted down and communicated.

Shortly after the earthquake in Pohang, the canton of Jura called for a review of the risk analysis for the planned petrothermal geothermal energy project in Haut-Sorne. The operator, Geo-Energie Suisse, has written an appraisal, which the SED is currently examining on behalf of the canton, taking account of all the known findings from Pohang. The SED is also involved in research work at the Bedretto Underground Laboratory for Geoenergies. There, along with other national and international partners, ETH Zurich, is conducting research to ascertain whether geothermal energy can be exploited safely, efficiently and sustainably using any existing technologies or procedures.

 

Science article "Managing injection-induced seismic risk"

Report by the commission (in Korean and English – scroll down and click on link to PDF file)

Science article "The November 2017 Mw 5.5 Pohang earthquake: A possible case of induced seismicity in South Korea"

2019-05-15

Seismic water feature

Seismic water feature

You don't need to go far to watch the ocean waves. The water feature of the fountain at the seaside resort of Enge in Zurich shows how the waves of the Atlantic, the Mediterranean or the Baltic Sea are behaving, in real time. At least, this is the signal most frequently transmitted to the fountain's control system by the Swiss Seismological Service's seismic station at ETH Zurich in Degenried, near the Dolder. Roughly once a week, the dynamics of the fountain change, whenever a major earthquake occurs somewhere in the world. With a bit of luck you might even see smaller-scale Swiss earthquakes.

Although Switzerland's seismic network, comprising over 150 stations, is designed to record earthquakes, it can actually do much more. In addition to capturing the movements of ocean waves, the highly sensitive measuring devices detect the sounds emanating from forests, the noise made by flowing traffic and explosions in quarries. The Swiss Seismological Service (SED) only systematically analyses recorded seismic data after earthquakes and explosions. The Aquaretum, the fountain in Lake Zurich, uses a small frequency range of the existing signal, which causes the harmonic motion of the fountain's jets of water.

In all, 12 water jets propel the water shoots up to heights of as much as 35 metres. They are arranged in four groups of three, representing the acceleration, speed and path of the transmitted signal respectively. These three parameters are also fundamental for analysing seismological data.

The Aquaretum was gifted to population and visitors of Zurich by the Zurich Insurance Group and made with the support of Fischer Architekten, the sound artist Andres Bosshard and the team from Metallatelier.

2019-04-25

The underground rock laboratory where even the smallest quakes are of interest

A unique research facility, the "Bedretto Underground Laboratory for Geoenergies", in the Bedretto valley in the Canton of Ticino is currently nearing completion. Together with national and international partners, ETH Zurich will investigate technologies and processes that should enable the safe, efficient, long-term use of geothermal energy. The Swiss Seismological Service at ETH Zurich is installing seven additional seismic stations in and around the rock laboratory. These instruments will be sensitive enough to record even the minutest tremors in the surrounding area.

The Bedretto Lab will be inaugurated on 18 May 2019. Take the opportunity to visit this unique rock laboratory and explore the history of the Alps deep inside a mountain. What's more, in front of the entrance tunnel leading to the lab you can learn more about the work that will be done there, test your knowledge by completing a rock quiz, see how core samples are produced and acquaint yourself with the various measuring systems used.

Register here for a free tour (in German or Italian).

Click here for some practical transport information.

Further information about the rock laboratory

2019-04-23

First potential marsquakes detected

First potential marsquakes detected

On 19 December 2018, the NASA InSight mission placed a seismometer on the surface of Mars. It aims to record marsquakes in order to to gain a better understanding of the planet’s interior. Since the very first day, the data recorded is continuously scrutinized by the Marsquake Service led by ETH Zurich, operated by the Seismology and Geodynamics group and the Swiss Seismological Service. At first, the data mostly showed the frequency and intensity of dust devils, whirlwinds which are very common on Mars. This already proved that the seismometer was performing well. On 6 April 2019 (Sol 128, 15:32 local Mars time), researchers from ETH on duty for the Marsquake Service discovered a potential marsquake in the data. It is the first signal that appears to have come from inside Mars, even though its exact cause is still an on-going scientific investigation.

Three other signals of likely seismic origin occurred on 14 March, 10 April, and 11 April 2019. These signals are more ambiguous to the InSight team than the one on 6 April, but do not appear to be clearly associated with atmospheric disturbances or other known noise sources. They are smaller than the event on 6 April and were only detected by the more sensitive broadband sensors. The team will continue to study these events to try to determine their origin.

Based on these first records, marsquakes seem to be distinct to earthquakes. According to their size and long duration, they are more similar to quakes recorded on the Moon by the Apollo programme. Whereas on Earth plate tectonics is the dominant process that provokes quakes, on the Moon the cooling and contraction causes tremors. The relevant processes at Mars are not yet fully understood. In any case, stress is built up over time until it is strong enough to break the crust. Different materials can change the speed of seismic waves or reflect them, allowing scientists to use these waves to learn about the interior of a planet and model its formation. The events recorded until now are too small to provide useful data on the deep Martian interior. Nevertheless, they mark a milestone of the InSight mission, proving the efficiency of the data processing and analysis capabilities, both developed at ETH Zurich.

TOPICS

Earthquake

Help, the Earth Is Shaking!

Help, the Earth Is Shaking!

Earthquakes are inevitable, but the damage they may be expected to cause can be mitigated in relatively simple ways. Find out the recommended behaviour before, during and after a powerful earthquake.

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Knowledge

Earthquake Country Switzerland

Earthquake Country Switzerland

Switzerland experiences between 1'000 and 1'500 earthquakes a year. Swiss citizens actually feel somewhere between 10 and 20 quakes a year, usually those with a magnitude of 2.5 or above. Based on the long-term average, 23 quakes with a magnitude of 2.5 or above occur every year. Find out more about the natural hazards with the greatest damage-causing potential in Switzerland.

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Alerting

Always Informed

Always Informed

If you want to be kept informed at all times, here you will find an overview of the various information services provided by the Swiss Seismological Service (SED).

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Knowledge

Earthquake Hazard

Earthquake Hazard

In Switzerland, earthquakes are the natural hazard with the greatest potential for causing damage. They cannot currently be prevented or reliably predicted. But, thanks to extensive research, much is now known about how often and how intensely the earth could shake at a given location in the future. Consult a variety of different maps using our interactive web tool to find out how likely certain earthquakes are in Switzerland.

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Research & Teaching

Fields of Research

Fields of Research

We are often asked what staff at the SED do when no earthquakes are occurring. The answer is they conduct research in a variety of fields, constituting SED's main scientific activities described in our research field section.

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About Us

Swiss Seismological Service (SED)

Swiss Seismological Service (SED)

The Swiss Seismological Service (SED) at ETH Zurich is the federal agency responsible for monitoring earthquakes in Switzerland and its neighboring countries and for assessing Switzerland’s seismic hazard. When an earthquake happens, the SED informs the public, authorities, and the media about the earthquake’s location, magnitude, and possible consequences. The activities of the SED are integrated in the federal action plan for earthquake precaution.

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Earthquakes

Earthquake Monitoring

Earthquake Monitoring

Around 10 to 20 times a year you will hear or read about an earthquake occurring in Switzerland. However, the vast majority of quakes recorded by the SED go unnoticed by the general public because they fall below the threshold of human perception and can only be detected by sensitive measuring devices. The Swiss Seismological Service (SED) operates a network of more than 150 seismic stations across Switzerland.

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Research and Teaching

Products and Software

Products and Software

Go to our Products page for access to seismic data and various apps.

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