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Ongoing Projects

This page provides details of selected ongoing projects managed by or prominently featuring staff from the Swiss Seismological Service (SED). The list is not exhaustive; it merely covers selected key or large-scale projects. The projects are grouped together according to the main focus of their research.

Induced Seismicity

DESTRESS is a Horizon 2020 supported programme aiming to demonstrate methods of EGS (enhanced geothermal systems) and thereby expanding knowledge and providing solutions for a more economical, sustainable and environmentally responsible exploitation of underground heat. EGS allow a widespread use of the enormous untapped geothermal energy potential. DESTRESS improves the understanding of technological, business and societal opportunities and risks related to geothermal energy.

The concepts explored are based on experiences in previous projects (e.g. GEISER), on scientific progress and developments in other fields, mainly the oil and gas sector. Recently developed stimulation methods are adapted to geothermal needs, applied to new geothermal sites and prepared for the market uptake. The main focus lays on stimulation treatments with minimized environmental hazard, which address site-specific geological requirements. The overall objective is to develop best practices in creating a reservoir with increased transmissivity, sustainable productivity and a minimized level of induced seismicity. Existing and new project’s test sites, pilot and demonstration facilities were chosen to demonstrate the DESTRESS concept.

DESTRESS assembles an international consortium involving major knowledge institutes and key industry from Europe and South Korea to guarantee the increase in EGS-technology performance and accelerated market penetration.

Project Leader at SED

Prof. Dr. Stefan Wiemer

SED Project Members

Dr. Toni Kraft, Michèle Marti, Isabel Schlerkmann

Funding Source

SBFI

Duration

2016-2020

Key Words

EGS (Enhanced geothermal systems), induced seismicity, risk mitigation, stimulation, demonstration sites

Research Field

Induced Seismicity

Link To Project Website

Project Website

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In the last few years, major and damaging earthquakes were felt in regions supposedly affected by a low rate of natural seismicity. Such events have become an extremely important topic of discussion in both Europe and North America, since several major events were associated to industrial activities. The main focus of this proposed research is the study of induced seismicity during exploitation of natural underground resources. More specifically, this proposal focuses on one side on a detailed understanding of the deep fault and/or fractures reactivation associated with the fluid injection. On the other side, the proposed research plans to investigate the mitigation of large magnitude induced seismicity, which may pose at risk the affected population and structures, as well as acting as obstacle to the development of new techniques for the exploitation of deep underground resources. First the project aims to understand the physics associated with the induced seismicity caused by anthropogenic activities. Secondly, the project aims to investigate in which conditions fluid-induced seismicity can be used as a tool. For example, the shearing process of fault and fracture, or the creation of new fractures, are needed to increase the permeability, and hence to enhance the fluid circulation at depth, eventually resulting in a more efficient energy production. However, such processes may, at the same time, produce seismicity that can be felt by local population.

  • How is the induced seismicity affecting the growth of a geothermal reservoir? When does it act as a potential seal breaching during storage operation?
  • Is it possible to use induced seismicity to develop a high permeability system, while constraining the earthquakes maximum magnitude? Or can a gas be stored in a safe (no seismic) way?

Understanding the fundamental processes will help in finding new methods to safely extract energy, whose request nowadays is constantly increasing.

The project will address the above open questions by theoretical studies, laboratory, and applied fieldwork. I plan to use data collected from on-going experiments (laboratory and in-situ) to improve numerical models. Numerical tools to be used include: thermo-hydromechanical modeling (THM), discrete fracture network (DFN), and statistical, as well as hybrid simulators.

Project Leader at SED

Antonio Pio Rinaldi

SED Project Members

Dominik Zbinden (PhD)

Funding Source

SNF

Duration

2015-2018

Key Words

Numerical modeling, Geomechanics, Hydrogeology, Multi-scale

Research Field

Induced Seismicity, Geothermal Energy, CO2 sequestration

Proposal

Antonio Pio Rinaldi To induce or not to induce: an open problem. Study on injection-induced seismicity for GeoEnergy applications, from lab to field scale. Research proposal for SNFN-Ambizione Energy grant. PDF 

Presentations

Antonio Pio Rinaldi (2015). To induce or not to induce: an open problem. Study on injection-induced seismicity for GeoEnergy applications, from lab to field scale. PDF 

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Der SED konnte in den letzten Jahren mehreren schweizerischen Tiefengeothermie-Projekten bei der seismischen Überwachung zur Seite stehen und so einen konstruktiven Dialog mit Betreibern und kantonalen Behörden beginnen. Auf diesen Erfahrungen aufbauend, hat der SED erste Empfehlungen für kantonale Bewilligungs- und Vollzugsbehörden entwickelt, wie mit der Problematik der induzierten Seismizität in verschiedenen Phasen eines Tiefengeothermie-projektes umzugehen ist. Diese Empfehlungen beruhen jedoch bislang auf Erfahrungen aus nur wenigen gut dokumentierten Projekten. Die praktische Erfahrung mit ihrer Umsetzung fehlt in der Schweiz bisher weitgehend. Es ist deshalb schwer abschätzbar, wie gut diese Empfehlungen im lokalen Kontext (geologisch, politisch, kulturell) anwendbar sind und welche Anpassungen gegebenenfalls getroffen werden müssen. Eine weitere wichtige Fragestellung ist in diesem Zusammenhang, wie Richtlinien und Vorschriften aus anderen technischen oder behördlichen Bereichen mit seismologischen Empfehlungen zur Vermeidung von induzierter Seismizität wechselwirken und vereinbar sind. Mögliche Konflikte lassen sich häufig nur in der praktischen Umsetzung von Projekten und durch die enge Zusammenarbeit des Seismologen mit Genehmigungsbehörden und Betreibern aufdecken und lösen. Ebenso wichtig ist die regelmässige Überprüfung und Anpassung aller relevanten Richtlinien und Vorschriften auf der Grundlage des wachsenden Kenntnis- und Erfahrungsstandes. Wenn immer möglich sollte dies im Konsens mit allen Interessengruppen geschehen.

Im Projekt Geobest-CH wird der SED daher weiter grundlegende Datensätze zur Entstehung der induzierten Seismizität bei Tiefengeothermieprojekten in hoher Qualität und Auflösung sammeln, auswerten und interpretieren. Ausserdem kann der SED so die Kantons- und Bundesbehörden bei ihren Genehmigungs- und Überwachungspflichten in allen Phasen eines Tiefengeothermieprojektes seismologisch beraten und unterstützen. Der SED will so dazu beitragen gleiche Bewertungsmassstäbe bei der Umweltverträglichkeitsprüfung über kantonale Grenzen hinweg zu schaffen und kurz- bis mittelfristig die Vereinheitlichung, und damit eine erhebliche Erleichterung und Beschleunigung, dieses Verfahrens ermöglichen. Über eine zentrale Webseite soll die Öffentlichkeit unabhängig, aktuell und fachlich kompetent zum Thema induzierte Seismizität informiert werden, um eine sachliche Diskussion aller Interessengruppen zu unterstützen.

Project Leader at SED

Toni Kraft

SED Project Members

S. Wiemer, M. Herrmann, A. Obermann, A. Mignan

Funding Source

energie-CH, Bundesamt für Energie

Duration

2015-2019

Key Words

Induced Seismicity, Induced Earthquake Hazard & Risk, Real-time monitoring, Support and consultancy

Research Field

Induced Seismicity, Induced Earthquake Hazard & Risk, Real-time monitoring, Support and consultancy

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Im Rahmen des Forschungsprojektes GeoBest führt der Schweizerische Erdbebendienst (SED) seit Frühjahr 2012 die seismologische Überwachung des Geothermieprojektes der Stadt St. Gallen durch. Dazu hat der SED in Zusammenarbeit mit den Sankt Galler Stadtwerken sechs neue Erdbebenmessstellen im Raum St. Gallen errichtet. Ziel der Überwachung ist es, mögliche kleine Erdbeben - sogenannte Mikrobeben - in der Umgebung der Tiefbohrungen zu detektieren und abzuklären, ob diese in Zusammenhang mit dem Geothermieprojekt stehen oder natürlichen Ursprungs sind. Ausserdem werden durch das Projekt wichtige Grundlagendaten für ein besseres Verständnis der Tiefengeothermie gesammelt, die als unentbehrlicher Erfahrungsschatz die Planungssicherheit der kantonalen Behörden und Projektbetreiber bei zukünftigen Geothermieprojekten gewährleisten sollen.

Nach der Einstellung des Geothermieprojekts im Frühjahr 2014 führt der SED die Überwachung in reduzierter Form für mindestens zwei weitere Jahre fort.

Project Leader at SED

Toni Kraft

SED Project Members

INDU group

Funding Source

Bundesamt für Energie, Sankt Galler Stadtwerke

Duration

2012-2017

Key Words

Research Field

Induced Seismicity, Real-time monitoring

Link To Project Website

Project Website

Publications

Edwards, B., Kraft, T., Cauzzi, C., Kastli, P., Wiemer, S. (2015). Seismic monitoring and analysis of deep geothermal projects in St Gallen and Basel, Switzerland. Geophys. J. Int. 201, 1020–1037. 

Obermann, A., Kraft, T., Larose, E., Wiemer, S. (2015). Potential of ambient seismic noise techniques to monitor the St. Gallen geothermal site (Switzerland). J. Geophys. Res. Solid Earth 120, 4301-4316. 

Diehl, T., Kraft, T., Kissling, E., Deichmann, N., Clinton, J. and Wiemer, S. (2014). High-precision relocation of induced seismicity in the geothermal system below St. Gallen (Switzerland). EGU General Assembly Conference Abstracts 16, 12541. 

Kraft, T., Wiemer, S., Deichmann, N., Diehl, T., Edwards, B., Guilhem, A., Haslinger, F. et al. (2013). The ML 3.5 earthquake sequence induced by the hydrothermal energy project in St. Gallen, Switzerland. AGU Fall Meeting Abstracts 1, 3. 

Kraft, T., et al. (2015). Lessons learned from the 2013 ML3.5 induced earthquake sequence at the St. Gallen geothermal site. Schatzalp Workshop on Induced Seismicity, Davos, Switzerland. 

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The exploitation of underground energy resources as well as the use and expansion of hydropower are, like any other energy technology, not risk free. To address this risk, we develop upon the holistic concept of risk governance and community resilience, advocating a broad picture of risk: In addition to risk analysis and risk management, we also investigate how risk-related decision-making unfolds when a range of actors is involved. This requires coordination and possibly reconciliation between a profusion of roles, perspectives, goals and activities. Developments include: a rigorous common methodology and a consistent modelling approach to hazard, vulnerability, risk, resilience and societal acceptance assessment of energy technologies; a stress test framework and its application to assess the vulnerability and resilience of individual critical energy infrastructures, as well as the first level of interdependencies among these infrastructures; standardized protocols, operational guidelines and/or softwares for monitoring strategies, hazard and risk assessment during all project phases (including real-time procedures), and finally for mitigation and related communication strategies.

Project Leader at SED

Prof. Stefan Wiemer

SED Project Members

Dr. Arnaud Mignan, Marcus Herrmann

Involved Institutions

ETH IfG, ETH D-BAUG, ETH D-USYS, ETH CRYOS

Funding Source

SCCER-SoE

Duration

2014-2017 (1st phase)

Key Words

Geo-energy, induced seismicity risk, risk governance, software

Research Field

Earthquake Hazard & Risk

Link To Project Website

Project Website

Reports / Deliverables

Mignan, A., Herrmann, M., Kraft, T., Diehl, T. and Wiemer, S. (2015). SCCER-SoE Science Report (Task 4.1) Link 

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The exploitation of underground energy resources as well as the use and expansion of hydropower, are, like all energy technologies, not risk free. The risks identified in the domain of deep geothermal are induced seismicity and other risks (e.g. borehole blowout, environmental risks). The hazard factors for hydropower are those classically affecting large arch or gravity dams, aggravated by the pronounced topography of the Alpine region and by the rapidly changing climatic conditions in the Alps. How these risks potentially impact our society, is, of course dependent on the vulnerabilities of our buildings, our infrastructure and our communities. Moving towards a safe and more resilient energy sector requires tools for hazard and risk assessment, particularly in the low probability-high consequence event settings. Furthermore, the tools have to be closely integrated with related communication and public engagement strategies, as perceived risks actually do impact energy source design and mitigation strategies. A comprehensive risk governance framework is necessary, but not yet existing. This project aims to develop such a framework by integrating risk assessment and related risk perception models and tools. This should lead to a communication strategy for future projects. We develop a holistic concept of risk governance from a truly multi-disciplinary perspective, advocating a broad picture of risk: not only does it include risk assessment and assessment of ability to recover, but it also looks at how risk perception and risk-related communication can be organized. This work is divided into 6 PhDs (attached to SCCER-SoE T4.1): Induced seismic risk (led by SED); Renewable energy risk management & optimization; Accident risks at dams; Vulnerability of the Swiss built environment; Multi-risks and interdependencies; Assessing and monitoring risk perception.

 

Project Leader at SED

Prof. Stefan Wiemer

SED Project Members

Dr. Arnaud Mignan, Marcus Herrmann

Involved Institutions

ETH IfG, ETH D-BAUG, ETH D-USYS, ETH CRYOS

Funding Source

SNF

Duration

2014-2017

Key Words

Geo-energy, induced seismicity risk, risk governance

Research Field

Earthquake Hazard & Risk

Reports / Deliverables

Mignan, A., Herrmann, M., Kraft, T., Diehl, T. and Wiemer, S. (2015). SCCER-SoE Science Report (Task 4.1) Link

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This is the 3rd subproject of the „ENSI – SED-Erdbebenforschung zu Schweizer Kernanlagen“ project.

Subproject 3 aims at studying the relevancy of induced seismicity for the disposal of nuclear waste at geological depth. We will update/develop physics-based modeling of induced seismicity, and we will apply such models to the case of nuclear waste disposal. Moreover, the approach will be validated by reproducing the observations from the “Fault Slip experiment” at Mont Terri underground laboratory. Finally, numerical modeling will be performed to study the seismicity induced by tunnel excavation, as well as to better understand the possible occurrence of seismicity by temperature changes around disposal site. Collaboration with Subproject 1 and 2 will be crucial to properly estimate the hazard and risk of induced seismicity on geological nuclear waste disposal.

Project Leader at SED

Donat Fäh

SED Project Members

Antonio P. Rinaldi, Luca Urpi

Involved Institutions

SED

Funding Source

Swiss Federal Nuclear Safety Inspectorate - ENSI

Duration

2014-2018

Key Words

Geomechanics, Induced seismicity, THM modeling

Research Field

Fields of Research

Earthquake Early Warning

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Scientists from the SED are exploring the potential of Earthquake Early Warning (EEW) in Central America. Funded by Swiss Agency for Development and Cooperation (SDC) at the Federal Department of Foreign Affairs (FDFA), scientists are the SED are working with colleagues at INETER, the agency responsible for monitoring seismicity in Nicaragua, to build and implement a prototype EEW system first in Nicaragua and hopefully extended to cover the wider region in Central America. The region suffers from large tsunamegenic earthquakes generated along the subduction zone (most recently M7.7 in 1992 and M7.3 in 2014), and also moderate crustal earthquakes that have in the recent past produced heavy damage, such as the M6.2 1972 earthquake that devastated Managua.

Earthquake Early Warning (EEW) is a tool that can rapidly characterize on-going earthquakes, and potentially provide seconds to 10s of seconds notification of impending strong shaking in advance of its occurrence. EEW can play an important role as part of a seismic risk reduction program, which is critical in the Central American region that has such a high seismic hazard. Additionally, making a seismic network capable of operating and maintaining an EEW system requires the network to achieve the highest standards in network performance - including station quality, speed and reliability of data communications, and robustness of the seismic network hub that runs the EEW software. Optimal network performance is also critical for other applications such as tsunami warning, volcano monitoring, and enables downstream scientific studies, eg on local Earth structure.

At the beginning of June, the SED visited INETER to evaluate the capability of the local seismic network and install first versions of the EEW software. Days after, on 9 June, a shallow M6.3 event occurred on the border with El Salvador that was detected by our system after 29s. Though optimisation is required to speed up the system, the infrastructure shows promise.

The project objectives are to 1) review the performance of, and propose improvements to the seismic network of Nicaragua, optimizing its capacity for EEW; and 2) to develop EEW algorithms tailored to the seismicity of Nicaragua and Central America, implement them in standard open source software available at INETER, and transfer operation to INETER.

A prototype EEW implementation will be developed that demonstrates the end-to-end functioning of the system and includes a limited number of recipients of EEW information. The project will propose the next steps towards a public EEW system for Nicaragua.

Project Leader at SED

John Clinton

SED Project Members

Yannik Behr, Maren Boese

Involved Institutions

INETER

Funding Source

Swiss Agency for Development and Cooperation (DEZA / SDC)

Duration

Jan 2016 - Jan 2018

Key Words

Earthquake Early Warning, Seismic Networks, Nicaragua, Central America, INETER, DEZA/SDC

Research Field

Earthquake Early Warning, Real-time monitoring, Network Seismology

Seismotectonics

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AlpArray is a European initiative to advance our understanding of orogenesis and its relationship to mantle dynamics, plate reorganizations, surface processes and seismic hazard in the Alps-Apennines-Carpathians-Dinarides orogenic system. The initiative integrates present-day Earth observables with high-resolution geophysical imaging of 3D structure and physical properties of the lithosphere and of the upper mantle, with focus on a high-end seismological array.

AlpArray is a major scientific collaboration with over 40 participant institutions. One of the main actions of the AlpArray initiative is to collect top-quality seismological data from a dense network of temporary broadband seismic stations. This complements the existing permanent broadband stations to ensure homogeneous coverage of the Alpine area, with station spacing on the order of 30km. 24 institutions are currently involved in the AlpArray Seismic Network (AASN), which will eventually install over 250 temporary stations in 12 countries. The AASN officially started on 1 January 2016 and will operate for at least 2 years. A complimentary ocean bottom seismometer (OBS) component is expected in 2017.

The Swiss contribution to the AASN is completed, with 23 temporary stations installed in Switzerland, Italy, Bosnia and Herzogovina, Croatia and Hungary. All national broadband stations also contribute to the AASN.

The Seismology and Geodynamics group (SEG) and the Swiss Seismological Service (SED) at the ETH in Zurich take leading roles in the project. Prof Edi Kissling is the project coordinator. Irene Molinari (SEG), John Clinton (SED) and Gyorgy Hetenyi (former SED, now at the University of Lausanne) lead AlpArray working groups, Irene Molinari also manages the Swiss component of the AASN.

More information is available on the project website.

Project Leader at SED

Edi Kissling (SEG)

SED Project Members

Irene Molinari (SEG), John Clinton, Stefan Wiemer, ELAB

Involved Institutions

Link

Funding Source

SNF

Duration

2015 - 2018

Key Words

Alps, earthquakes, seismic broadband network, tomography, geodynamics, surface process, orogenesis

Research Field

Seismotectonics, Real-time monitoring, Earthquake Hazard & Risk

Link To Project Website

Project Website

Proposal

(2013). Alp Array - Probing Alpine geodynamics with the next generation of geophysical experiments and techniques PDF 

Publications
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Um in Zukunft die Gefahren von natürlichen und induzierten Erdbeben besser abschätzen zu können, braucht es ein genaueres Verständnis von Verwerfungszonen in tektonisch aktiven Gebieten wie der Schweiz. Mit Hilfe geophysikalischer Abbildungsverfahren und geologischen Kartierungen wurden in den letzten Jahren zahlreiche Verwerfungen in den schweizerischen Alpen und im nördlichen Alpenvorland identifiziert. Allerdings treten in vielen Fällen Erdbeben abseits dieser kartierten Verwerfungen auf, was die Frage nach den tektonischen Prozessen und Mechanismen aufwirft, die diesen Erdbeben zugrunde liegen.  

Ziel dieses Projektes ist es, durch verbesserte geophysikalische Inversionsverfahren die Strukturen von Verwerfungszonen hochauflösend abzubilden und daraus Erkenntnisse über mechanische Eigenschaften der Bruchsysteme abzuleiten. Dazu werden unter anderem Verfahren der seismischen Tomografie mit hochauflösender Erdbebenlokalisierung kombiniert. Die Anwendung konzentriert sich auf zwei Regionen in der Schweiz: (i) einer äußerst aktiven Erdbebenzone nördlich des Rhônetals im Kanton Wallis, (ii) einer Verwerfungszone nahe St. Gallen, die während Stimulationsmaßnahmen für ein geplantes Geothermiekraftwerk aktiviert wurde.

Durch die Anwendung verbesserter Abbildungsverfahren erwarten wir zum einen neue Erkenntnisse über den Zusammenhang zwischen existierenden Verwerfungen und dem Auftreten von Erdbeben. Zudem sind die beiden Untersuchungsgebiete von hoher gesellschaftlicher Relevanz. Das Wallis ist die Region mit der größten seismischen Gefährdung der Schweiz und ein Großteil der gegenwärtigen Seismizität in diesem Gebiet steht in Verbindung mit der Erdbebenzone nördlich des Rhônetals. Die St. Gallen Verwerfungszone bietet Gelegenheit zur Untersuchung der Erdbebengefährdung im dicht besiedelten Molasse Becken, welches potentieller Standort zukünftiger Geothermieprojekte und atomarer Endlager ist.

Project Leader at SED

Tobias Diehl

SED Project Members

Edi Kissling, Stefan Wiemer

Funding Source

SNF

Duration

3 years

Key Words

seismicity, seismotectonic, earthquake location, seismic tomography, reflection seismics, induced seismicity, geothermal energy, fault zone, Rawil, St. Gallen, Valais, seismic hazard, Molasse basin

Research Field

Seismotectonics (main), but also: Induced Seismicity, Swiss Seismicity, Earthquake Statistics

Proposal

Diehl, Kissling, Wiemer SAMSFAULTZ: Structure And Mechanics of Seismogenic Fault Zones: Insights from advanced passive and active seismic imaging PDF 

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This project is carried out under a contract with the National Cooperative for the Disposal of Radioactive Waste (Nagra). It provides an independent monitoring of the earthquake activity in the area of the proposed nuclear waste repositories in northern Switzerland. Detailed microseismic analysis will help to identify active fault zones and provide insights into the underlying seismotectonic processes in the vicinity of proposed sites, which has direct implications on the seismic hazard assessment. The SED provides results of this project in a transparent manner and all data acquired are made available for public access (see SED declaration on transparency [link]).

Within this project, the Swiss Seismological Service (SED) constructed ten new seismic stations in northeastern Switzerland and southern Germany to improve monitoring capabilities for very small earthquakes. Monitoring of weak seismic events in this region is challenging, because the study region is densely populated and sediments of the Molasse basin dominate the surface geology. A novel step-wise optimization approach was developed to ensure an optimum configuration of the new stations. To reduce the seismic background noise, three of the ten new sites were equipped with borehole-sensors, located at depths of 120–150 m below the surface. The new stations are fully operational since December 2013 and will observe the local seismicity in northern Switzerland for a minimum of ten years.

The newly installed stations complement the five stations installed in 2003 under a first agreement with Nagra. With these ‘Nagra’ stations, together with stations of the Swiss National Seismic Network and stations of neighboring networks in Germany, the project aims to monitor earthquakes down to magnitudes of 1.0 and smaller in the study area. We intend to achieve an overall catalog completeness of Mc 1.3 throughout northeastern Switzerland and location errors less than 0.5 km in epicenter and less than 2 km in focal depth within the study region. Accurate earthquake locations are essential for seismotectonic interpretations. Within this project we therefore aim to improve location accuracy, especially for focal depths, of past and future earthquakes in the region.

Project Leader at SED

Tobias Diehl

SED Project Members

Florian Haslinger, Stefan Wiemer, Donat Faeh, Toni Kraft, John Clinton

Involved Institutions

Nagra

Funding Source

Nagra

Duration

2013-2019

Key Words

seismicity, seismotectonic, earthquake location, seismic hazard, Molasse basin, nuclear waste repositories

Research Field

Seismotectonics (main), but also: Swiss Seismicity, Real-time monitoring, Earthquake Hazard & Risk

Publications

Kraft, T., Mignan, A., Giardini, D. (2013). Optimization of a large-scale microseismic monitoring network in northern Switzerland. Geophys. J. Int. 19, 474-490. doi: 10.1093/gji/ggt225

Diehl, T., Korger, E., Clinton, J., Haslinger, F., Wiemer, S.  (2015). Annual Report on Network Performance and Seismicity 2014. ETH Zurich. 

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Bhutan, a kingdom in the Eastern Himalayas, is living in self-imposed isolation: in order to preserve local culture, traditions and the environment, foreigners can enter in groups and in limited number only. Consequently, our geoscientific knowledge is very limited compared to other parts of the orogen. The first geological map was compiled in 1983 by the famous Swiss geologist Augusto Gansser. From a geophysical perspective, Bhutan is almost a blank spot: only very limited information exists on seismicity which shows a lower level of earthquake activity compared to other parts of the Himalayas; there is knowledge neither of the structure nor of the physical properties of the crust and the lithosphere. Illuminating the deep structure of Bhutan and comparing it with the much better known Central Himalayas of Nepal is highly relevant both for evaluating the earthquake hazard and for improving our geodynamic picture of the orogen.

We conducted a temporary seismic experiment in Bhutan. Two densely spaced profiles across the orogen allow us to produce the first images of the structure of the lithosphere in the Eastern Himalayas, as well as give an insight into lateral variations along the mountain belt. Our network provides reliable information on seismicity in Bhutan and establishes the first seismic velocity model of the crust. Furthermore, we will apply ambient noise tomography to map the physical properties of the lithosphere. The results will be interpreted jointly with gravity data to build physical models of the Eastern Himalayas as well as to draw conclusions on its geodynamics. Especially, seismotectonic studies that we plan to conduct by comparing different segments of the Himalayas may shed light on the origin of the apparent seismic gap in Bhutan.

Augusto Gansser, "Geology Father of the Himalayas" and first geological mapmaker of Bhutan, has passed away earlier this year (2012), at the age of 101. We would like to dedicate this experiment to his memory.

Outreach

Project Leader at SED

György Hetényi

SED Project Members

Tobias Diehl, John Clinton, Julia Singer (SEG), Edi Kissling (SEG)

Involved Institutions ETH Zürich, Zürich, Switzerland; Department of Geology and Mines, Thimphu, Bhutan
Funding Source

SNF

Duration

3 years

Key Words

Himalaya, Bhutan, continental collision, seismology, geodynamics, geophysics, crust, lithosphere, earthquake, seismotectonics

Research Field

Earth structure, Seismotectonics, Geodynamics, Earthquake Hazard & Risk

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The Eastern, "straight" part of the Alps is home to a number of open questions. The most widespreadly known question is about lithospheric slab hanging beneath the Eastern Alps. Is it Adriatic (Lippitsch et al. 2003)? Is it European (Mitterbauer et al. 2011)? What is its extent and the related velocity anomaly?

Beyond carrying out tomographic calculations, one can also characterize the fabric of the lower crust with receiver functions. In the India-Asia collision zone this has helped to point out that the main lithosphere boundary is located at a very different place than the surface boundary of deformation. Anisotropic receiver function calculations are therefore one of the first tools to be applied on EASI data, with the main question of determining the role of the lower crust in shaping the orogen.

A recent Moho map compilation reveals another interesting features beneath the Eastern Alps and between the Europe and Adria plates: a Moho "gap" or "hole" (Spada et al. 2013). Near 47°N latitude and between 12° and 15.5°E longitude the crust-mantle boundary is not defined, or at least it does not appear as a sharp discontinuity. Mapping the extent of this hole, and characterizing the velocity gradient from crustal to mantle conditions is an interesting goal to tackle.

The relationship of the Alpine orogen to the adjacent foreland basin and the lithospheric blocks of the Bohemian Massif, with their own characteristic seismic signatures, is a structural target of EASI.

Our research methods include tomography, ambient noise analysis and receiver functions, with anisotropy included in all three types of investigations. The depth range of investigations encompasses the crust and the mantle lithosphere, down to the LAB.

Project Leader at SED

György Hetényi

SED Project Members

Edi Kissling (SEG)

Involved Institutions

Institute of Geophysics, Czech Academy of Sciences, Prague, Czech Republi; Universiy of Vienna, Vienna, Austria; ETH Zürich, Zürich, Switzerland; INGV Rome-Bologna-Genova, Italy

Funding Source

ETH (for the Swiss part)

Duration

2 years

Key Words

Alps, continental collision, seismology, geodynamics, geophysics, crust, lithosphere, earthquake, seismotectonics, slab, Moho

Research Field

Earth structure, Seismotectonics, Geodynamics

Realtime Monitoring

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InSight (Interior exploration using Seismic Investigations, Geodesy and Heat Transport) is a NASA Discovery Program mission that will deploy a single geophysical lander on Mars to study its deep interior. This is the first comprehensive surface-based geophysical investigation of Mars. The overarching mission goals are to illuminate the fundamentals of formation and evolution of terrestrial (Earth-like) planets by investigating the interior structure and processes of Mars, and more specifically to determine the thickness, structure and composition of the crust, mantle and core, and to measure the rate and distribution of seismic activity and the rate of meteorite impacts. The Mission should land in November 2018 and have a lifetime of about two Earth years. A set of 3-component broadband and short period seismometers (collectively known as SEIS) will be deployed beside the lander. In additional, InSight will also deploy a heat flow probe (HP3), a geodetic experiment (RISE), a magnetometer, and meteorological sensors. Seismological investigations of Mars have so far been based on modeling and synthetic data; starting in 2018, waveform data will be returned from Mars and the era of 'Seismology on Mars' will begin.

Building on our expertise and infrastructure for earthquake monitoring and seismic data processing on Earth, the SED will take the lead role in the building a catalogue of seismic events recorded by SEIS (the 'Marsquake Service’). This service will comprise automatic and reviewed event detection and characterization of local and teleseismic events, as well as meteor impacts. The goal of this service is to provide a comprehensive high-quality event catalogue for Mars that is critical to the SEIS project, in particular as input to the development of Martian crustal and deep structure models.

We are adapting advanced single-seismometer analysis techniques developed on the Earth to provide locations for Martian seismicity. Creating the Marsquake Service is a collaboration between the SED and the SEG groups at the ETH Zurich.

Project Leader at SED

Prof. Dr. Domenico Giardini (InSight Co-I)

SED Project Members

Dr. John Clinton (Seismic Network Manager, InSight Co-I)

Dr. Amir Khan (Affiliated Scientist)

Dr. Martin van Driel (PostDoc)

Dr. Maren Böse (Project Scientist)

Dr. Fabian Euchner (PostDoc)

Dr. Savas Ceylan (IT Specialist)

Funding Source

SNF / SSO

Duration

2015 - 2018

Key Words

Planetary seismology, Mars, InSight, single-station approaches, seismic monitoring

Research Field

Link To Project Website

Project Website

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SED installed 3 seismological stations in the surroundings of the Mont Terri rock laboratory (St Ursanne, Canton Jura): 2 in the tunnel (stations MTI01 and MTI02) and 1 at the surface (MTI03). The Engineering Seismology group is in charge of the site characterization of these 3 stations. Therefore, a literature review and geophysical experiments are performed in order to propose velocity models able to reproduce the ground motion observed at these stations.

Project Leader at SED

Donat Fäh

SED Project Members

Valerio Poggi, Clotaire Michel, Sacha Barman, Robin Hansemann

Involved Institutions

SED

Funding Source

Swisstopo

Duration

2013-2023

Key Words

Earthquake monitoring, Ground motion at depth

Research Field

Strong Motion Seismology

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Since 2009, the Swiss Seismological Service is renewing and expanding its strong motion network. During the first phase, a total of 30 new accelerometer stations have been installed between 2009 and 2013, both replacing existing strong motion dial-up stations and installing new stations. During the ongoing second phase, 70 more stations are planned to be installed by 2019, including 4 borehole installations. The renewal project of the Swiss Strong Motion Network was approved by the Swiss Federal Council in February 2009. The project is monitored and supervised by a steering committee headed by the Swiss Federal Office for the Environment (FOEN).

The goals of the enlargement of the Swiss strong motion network are a better spatial coverage of earthquake prone regions, a better understanding of site-effects and thus the verification and improvement of hazard models. The epicentral areas of relevant past earthquakes have been instrumented in the first phase, namely Aigle (1584), Glarus (1971), Sarnen (1964), Sion-Sierre (1946), Yverdon (1929), Visp (1855), St. Gallen Rhine Valley (1796/96), Altdorf (1774), Brig (1755), Basel (1356), Churwalden/Vaz (1295/1991), etc. Further, the city areas of Zürich, Geneva, Basel, Bern, Lausanne, St. Gallen, Lucerne, Sion, Solothurn, Locarno, Chur, Sierre are relevant sites for free-field installation.

In the second phase, additional epicentral areas of past earthquakes are targeted, Churwalden (1295), Ardez (1504), Ardon (1524), Arbon (1720), Kreuzlingen (1911), and Moudon (1933), among others. Further urban areas are instrumented as well, e.g. Biel, Fribourg, Neuchâtel, Thun, Winterthur.

The site selection is always a trade-off between the scientific objectives and the level of vibration disturbances. Modern stations are sensitive enough to record also small earthquakes, but the signal-to-noise ratio may be too low due to traffic and industries. At all sites, geophysical measurements are performed to characterize the site response. Recorded signals can then be interpreted, and sites classified according to the amplification at the site, which is basic information for improved site-specific seismic hazard studies.

Project Leader at SED

Donat Fäh

SED Project Members

Manuel Hobiger, Christian Scherrer, Clotaire Michel, Franz Weber, John Clinton, Carlo Cauzzi

Involved Institutions

BAFU

Funding Source

BAFU

Duration

2013-2019

Key Words

SSMNet, strong motion, site characterization

Research Field

Swiss Seismicity, Earthquake Hazard & Risk

Publications

Michel C., Edwards B., Poggi V., Burjánek J., Roten D., Cauzzi C. & Fäh D.  (2014). Assessment of Site Effects in Alpine Regions through Systematic Site Characterization of Seismic Stations. Bull. Seismol. Soc. Am.  104(6).  Link  doi: 10.1785/0120140097

Historical Seismology

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The goal of this project is the historical-critical revision of the Swiss earthquake catalogue for the pre-instrumental and early instrumental period of systematic earthquake observations in Switzerland, 1878–1963, with a special focus on events of intermediate magnitude reaching epicentral intensities of IV–VI (EMS-98).

To ensure correct interpretation of the large amount of heterogeneous scientific and non-scientific earthquake records, it is essential to investigate the historical, scientific and technological context of their production. This is achieved through the approaches of historical sciences. The proposed work relies on a systematic investigation and a historically sound assessment of the reliability and factuality of historically reported events.

By the use of descriptive primary and secondary sources, macroseismic intensity fields will be established for intermediate-size earthquakes with an intensity in the range IV–VI (EMS-98). This will facilitate the assessment of event parameters such as magnitude, location and depth in a calibrated procedure that will be developed in the project. These parameters are verified by the analysis of the historical seismograms of the Swiss Seismological Service’s early instrumental station network.

Project Leader at SED

Donat Fäh

SED Project Members

Remo Grolimund

Funding Source

SNF

Duration

2015-2018

Key Words

Historical Seismology, Interdisciplinary, Historical Seismogram Analysis, Macroseismics, History of Science and Technology

Research Field

Swiss Seismicity, Earthquake Hazard & Risk, Historical Seismicity

Link To Project Website

Project Website

Engineering Seismology

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The second phase of this project (previously refered to "Expertengruppe Starkbeben") is split into 2 subtasks with the main goal to improve regional and local seismic hazard assessment in Switzerland; with particular focus to the sites of potential regions of nuclear repositories. These sub-projects are:

Subproject 1 aims to improve models and develop methods for the prediction of strong ground motion in Switzerland at the surface and at depth. Two main approaches are investigated: ground motion prediction equations (GMPEs) and stochastic simulation models. Both approaches require calibration to the local seismicity and careful consideration of their extrapolation to large magnitude events which have, as yet, not been instrumentally recorded in Switzerland. We use recordings of local seismicity in addition to numerical modelling results (subproject 2) to calibrate the predictive models for use in engineering practice.

Subproject 2 is focused on earthquake scenario modeling for Switzerland and exploration of the physical limits on ground motion. Our modeling combines realistic dynamic rupture along irregular fault surfaces and wave propagation in complex heterogeneous media at high frequency. Moreover we investigate the plastic and non-linear behavior of soft sediments at the Earth surface, conducting CPT measurements to calibrate our numerical models.

Subproject 3 focuses on numerical modeling the induced seismicity during tunnel excavation. Simulations will be performed using both thermo-hydro-mechanical coupled model and statistical model. We will investigate the risk of inducing seismicity during short-term active tunnel excavation and at later time. Numerical simulation will be also performed to match the fault slip experiment at Mont Terri. Finally, the results will be used as input for Subproject 1 and 2.

Project Leader at SED

Donat Fäh

SED Project Members

Walter Imperatori, Marco Pilz, Antonio Rinaldi, Luca Urpi

Funding Source

Swiss Federal Nuclear Safety Inspectorate - ENSI

Duration

2014-2018

Key Words

Ground motion prediction equations, ground motion modelling, induced seismicity

Research Field

Swiss Seismicity, Earthquake Hazard & Risk

Reports / Deliverables

D. Fäh, S. Wiemer, D. Roten, B. Edwards, V. Poggi, C. Cauzzi, J. Burjanek, M. Spada, R. Grolimund, M. Gisler, G. Schwarz-Zanetti, P. Kästli (2012). Expertengruppe Starkbeben. ENSI Erfahrungs- und Forschungsbericht 2011, 173-182. Eidgenösisches Nuklearsicherheitsinspektorat ENSI.  PDF 

D. Fäh, S. Wiemer, B. Edwards, V. Poggi, D. Roten, R. Grolimund, M. Spada, J. Wössner (2013). Expertengruppe Starkbeben. ENSI Erfahrungs- und Forschungsbericht 2012, 173-181. Eidgenösisches Nuklearsicherheitsinspektorat ENSI.  PDF 

D. Fäh, S. Wiemer, B. Edwards, V. Poggi, D. Roten, R. Grolimund, M. Spada, B. Schechinger, J. Woessner (2014). Expertengruppe Starkebeben. ENSI Erfahrungs- und Forschungsbericht 2013, 161-170. Eidgenösisches Nuklearsicherheitsinspektorat ENSI.  PDF 

D. Fäh, S. Wiemer, B. Edwards, V. Poggi, D. Roten, R. Grolimund, M. Spada, B. Schechinger , T. Tormann, J. Woessner (2015). Earthquake Strong Motion Research. ENSI Erfahrungs- und Forschungsbericht 2014, 171-180. Eidgenösisches Nuklearsicherheitsinspektorat ENSI.  PDF 

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This group gathers the researchers with competences in site characterization in order to discuss and improve the work performed for different projects involving site characterization, especially for sites with new seismic stations. The available tools for processing, archiving and disseminating are shared within the group. The group is responsible for setting up and filling the SED database for site characterization. A process of review has been established in order to validate the work done before it is made public.

The group reviewed the 30 sites of the SSMNet Renewal phase 1, 6 sites of SSMNet stations in Basel installed in the frame of the Basel Erdbebenvorsorge project, the 10 sites of the NAGRA Network, the installation site of stations in the area of the Mont Terri rock laboratory, 2 sites of SSMNet stations in Liechtenstein and the currently installed sites of the SSMNet Renewal Phase 2.

Project Leader at SED

Donat Fäh

SED Project Members

Clotaire Michel, Jan Burjanek, Manuel Hobiger, Marco Pilz, Walter Imperatori, Ulrike Kleinbrod, Stefano Marano, Carlo Cauzzi

Funding Source

Site characterization projects (SSMNet reneval project (BAFU), NAGRA, Canton BS and others)

Duration

Since 2010

Key Words

Site characterization, strong motion stations, broadband stations, site response, site effects, site amplification, field

Research Field

Earthquake Hazard & Risk, Engineering Seismology

Link To Project Website

Project Website

Publications

Michel, C., Edwards, B., Poggi, V., Burjanek, J., Roten, D., Cauzzi, C. and Fäh, D. (2014). Assessment of site effects in Alpine regions through systematic site characterization of seismic stations. Bulletin of the Seismological Society of America 104(6), 2809-2826. doi: 10.1785/0120140097

Burjánek, J., Edwards, B. and Fäh, D. (2014). Empirical evidence of local seismic effects at sites with pronounced topography: a systematic approach. Geophysical Journal International 197(1), 608-619. doi: 10.1093/gji/ggu014

Edwards, B., Michel, C., Poggi, V. and Fäh D. (2013). Determination of Site Amplification from Regional Seismicity: Application to the Swiss National Seismic Networks. Seismological Research Letters 84(4), 611-621. doi: 10.1785/0220120176

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Within this project, new signal processing techniques for the analysis of ambient vibrations are developed. The focus is on the development of single-station methods and the adaptation of existing techniques to large arrays.

Single-station methods represent an extremely valuable tool. The use of a single station further simplifies the measurement procedure thus enabling a more time and cost effective survey.

Assumptions on the wavefield used when processing small arrays may be no longer valid when analyzing large arrays. For this reason, we investigate adaptations of existing techniques to large arrays.

Target applications of the methods developed within this project include microzonation studies in Switzerland and investigation of the characteristics of the Swiss Molasse Basin.

Project Leader at SED

Donat Fäh

SED Project Members

Stefano Maranò, Dario Chieppa (PhD)

Funding Source

SNF

Duration

Since 2014

Key Words

Ambient vibrations, surface waves

Research Field

Earthquake Hazard & Risk, Signal Processing

Publications

Maranò, S., Fäh, D. and Loeliger, H.-A.  (2015). A state-space approach for the analysis of wave and diffusion fields. Acoustics, Speech, and Signal Processing, 2564-2568. IEEE Int. Conf. . doi: 10.1109/ICASSP.2015.7178434

Statistical Seismology

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Recent discoveries include: Non-volcanic tremors (NVT), strong heterogeneity of the relative stress distribution, temporal and along-fault variable aseismic creep, repeating earthquakes, slow slip events. Based on the insight that was gained from these previous studies, we will be able to develop and calibrate an indicative stress-meter for the Earth’s crust. In this project we link for the first time the statistical analysis of the size distribution of earthquakes with complementary observations of fault movement.

This yields an improved understanding of the nature of fault loading cycles. Therefore, the results will provide key understanding to unravelling the predictability of earthquakes and has the potential to radically change the assessment of local seismic hazard for selected well-understood and well-monitored faults.

Project Leader at SED

Prof. Dr. Stefan Wiemer

SED Project Members

Nadine Staudenmaier, Dr. Thessa Tormann

Funding Source

SNF

Duration

2013-2017

Key Words

Non-volcanic tremors (NVT), strong heterogeneity of the relative stress distribution, slow slip events

Research Field

Earthquake Statistics, Seismotectonics

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Quantifying time-varying seismicity rates is fundamentally important to protecting people who live in areas subject to extreme earthquake shaking. One primary difficulty with such assessment is determining how faults interact. Some recent studies have noted the ability of passing earthquake waves to increase the 'triggerability' of a fault in a delayed form of dynamic stressing: after seismic waves pass, faults are more prone to fail in a subsequent earthquake. The deadly Canterbury earthquake sequence has characteristics that suggest it was promoted by such distant, delayed, dynamic triggering. The sequence is also compatible with a model in which low-strain rate areas are efficient at storing and transferring static stresses. This has implications for earthquake clustering and the generation of damaging ground motion. We will apply recently-developed techniques in concert to address three questions: 1) Can we quantify distant and delayed triggering in this sequence? We will address this by correlating increased geodetic crustal velocities in Canterbury following the 2009 M7.8 Dusky Sound earthquake that occurred hundreds of km away. We will apply source scanning and template matching techniques to search Canterbury for microseismicity that was triggered by the M7.8 event. 2) Do earthquakes in low-strain rate areas exhibit more clustering and longer aftershock sequences than their high-strain rate counterparts, and do these earthquakes produce stronger ground motions? We will build a comprehensive model of earthquake generation in low-strain rate areas by using an earthquake simulator to model the evolution of the sequence. 3) Can the simulator model we develop demonstrate skill in seismicity forecast experiments? The model developed in this project could provide a true step change and bring seismology closer to bridging the gap between probabilistic forecasting and deterministic modelling of earthquake hazard.

Project Leader at SED

Dr. J. Douglas Zechar

SED Project Members

Yifan Yin

Involved Institutions

GNS Science

Funding Source

ETH

Duration

2015-2018

Key Words

Delayed dynamic triggering; earthquake physics; earthquake simulator; earthquake forecasting

Research Field

Earthquake Hazard & Risk, Earthquake Statistics

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Our present knowledge about earthquakes does not yet allow us to reliably forecast earthquakes. Therefore, the study of precursors is an essential step in the direction of earthquake forecasting. Precursors can be anomalous seismic patterns or other phenomena such as peculiar animal behavior, or electromagnetic anomalies etc., which indicate the incidence of a large event. We focus in our studies on seismic precursors, namely quiescence, which is expressed through reduced seismic activity, accelerated seismicity (ASR) and short term foreshocks. The mentioned precursors are observed in many selected earthquake sequences in the past. However, there is skepticism if these precursors happen systematically; some studies explain their occurrence rather as a random temporary perturbation of normal seismicity which is accidentally followed by a large earthquake.

We believe that systematic investigations on the occurrence of precursors give essential evidence for or against their existence. We chose to perform these investigations with statistical tools, hence by evaluating location, time and magnitudes of earthquakes from several regional earthquake catalogs of the world, to obtain representative precursor statistics.

We find that small earthquakes, as they occur more frequently, could facilitate the detection of precursory patterns (Mignan, 2014). We study statistical models used to describe earthquake occurrence and the impact of the choice of the lowest magnitude on them (Seif et al, 2016, submitted). Using these models we evaluate if foreshock occurrence differs from normal seismicity. We also want to specify how often foreshock patterns are followed by large events or not (true/false alarm rate). In the future remaining precursory patterns, quiescence and accelerated seismicity, will be investigated in the same way. We hope that the statistical analysis will allow us to better understand the physical processes which lead to the occurrence of precursors.

Project Leader at SED

Dr. Arnaud Mignan

SED Project Members

Stefanie Seif, Dr. Jeremy Zechar, Prof. Stefan Wiemer

Funding Source

ETH Grants

Duration

2013 - 2017

Key Words

Precursors, foreshocks, cut-off magnitude, ETAS

Research Field

Earthquake Statistics, Earthquake Forecasting

Publications

Mignan, A. (2014). The debate on the prognostic value of earthquake foreshocks: A meta-analysis. Scientific reports, 4:4099. doi: 10.1038/srep04099

Seif, S., Mignan, A., Zechar, J., Werner, M. and Wiemer, S. Estimating ETAS: the effects of truncation, missing data, and model assumptions

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Statistical seismology is the application of rigorous statistical methods to earthquake science with the goal of improving our knowledge of how the earth works. Within statistical seismology there is a strong emphasis on the analysis of seismicity data in order to improve our scientific understanding of earthquakes and to improve the evaluation and testing of earthquake forecasts, earthquake early warning, and seismic hazards assessments. Given the societal importance of these applications, statistical seismology must be done well. Unfortunately, a lack of educational resources and available software tools make it difficult for students and new practitioners to learn about this discipline. The goal of the Community Online Resource for Statistical Seismicity Analysis (CORSSA) is to promote excellence in statistical seismology by providing the knowledge and resources necessary to understand and implement the best practices.

CORSSA covers a wide variety of themes:

Introductory Material
Statistical Foundations
Understanding Seismicity Catalogs and Their Problems
Models and Techniques for Analyzing Seismicity
Earthquake Predictability and Related Hypothesis Testing

Each of these themes includes a series of articles that are listed in the CORSSA Table of Contents. The series of themes was devised to make it easy for the reader to focus on their personal requirements to get an introduction to statistical seismology, or to learn about the basics of earthquakes, statistics, and/or the intricacies of seismicity catalogs before moving onto applications.

Project Leader at SED

Dr. J. Douglas Zechar

SED Project Members

Stefan Wiemer

Funding Source
Duration

2011-present

Key Words

Statistical seismology, aftershocks, declustering

Research Field

Earthquake Hazard & Risk, Earthquake Statistics

Publications

Zechar, J.D., Hardebeck, J., Michael, A., Naylor, M., Steacy, S., Wiemer, S. and Zhuang, J. (2011). Community Online Resource for Statistical Seismicity Analysis. Seismological Research Letters. doi: 10.1785/gssrl.82.5.686

Numerical Modeling

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This is the 1st subproject of the „ENSI – SED-Erdbebenforschung zu Schweizer Kernanlagen“ project.

This subproject aims to improve source-scaling and attenuation models and to develop methods for the prediction of strong ground motion in Switzerland both at the surface as well as at depth. Two main approaches are investigated: ground motion prediction equations (GMPEs) and stochastic simulation models. Both approaches require adaptions to the local seismicity and careful consideration of their calibration to Swiss conditions. The stochastic model corresponds to the current state of research and has some advantages over the empirical attenuation relationships, as it is possible to adjust the model to specific local site conditions. The complete understanding in terms of physical parameterization of such models is crucial in order to decouple different effects, which allow building robust predictive models that scale appropriately to large magnitude events. To this regard, a model from Japanese data is now being developed that will allow the review of the Swiss model for large magnitudes in the different distance ranges and at various rock sites which have, as yet, not been instrumentally recorded in Switzerland. Moreover, we will use recordings of local seismicity in addition to numerical modeling results of related projects to calibrate the predictive models. The long-term goal is to develop an improved stochastic simulation model for Switzerland allowing existing uncertainties to be reduced. In future, such models will also allow an assessment of ground motion caused by induced seismicity due to the activation of existing fractures and/or the generation of new fractures.

Project Leader at SED

Donat Fäh

SED Project Members

Marco Pilz

Involved Institutions

Department of Earth, Ocean and Ecological Sciences, University of Liverpool

Funding Source

Swiss Federal Nuclear Safety Inspectorate - ENSI

Duration

2014-2018

Key Words

Ground motion prediction equations, stochastic ground motion models

Research Field

Swiss Seismicity, Earthquake Hazard & Risk

Publications

Edwards, B. & Fäh, D.  (2014). Ground motion prediction equations Link  doi: 10.3929/ethz-a-010232326

Edwards, B., Ktenidou, O.-J., Cotton, F., Abrahamson, N., Van Houtte, C. and Fäh, D (2014). Epistemic Uncertainty and Limitations of the Kappa0 model for Near-surface Attenuation at Hard Rock Sites. Geophysical Journal International 202(3). doi: 10.1093/gji/ggv222

Edwards, B. and Fäh D. (2013). A Stochastic Ground‐Motion Model for Switzerland. Bulletin of the Seismological Society of America 103, 78-98. doi: 10.1785/0120110331

Edwards, B., Michel, C., Poggi, V. and Fäh, D. (2013). Determination of Site Amplification from Regional Seismicity: Application to the Swiss National Seismic Networks. Seism. Res. Lett. 84(4), 611-621. doi: 10.1785/0220120176

Poggi, V., Edwards, B. and Fäh, D (2013). Reference S-wave velocity profile and attenuation models for ground-motion prediction equations: application to Japan. Bulletin of the Seismological Society of America 103(5), 2645-2656. doi: 10.1785/0120120362

Poggi, V., Edwards, B. and Fäh, D. (2012). Characterizing the vertical to horizontal ratio of ground-motion at soft sediment sites. Bulletin of the Seismological Society of America 102(6), 2741-2756. doi: 10.1785/0120120039

Poggi, V., Edwards, B. and Fäh, D. (2011). Derivation of a Reference Shear-Wave Velocity Model from Empirical Site Amplification. Bulletin of the Seismological Society of America 101(1), 258-274. doi: 10.1785/0120100060

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This is the 2nd subproject of the „ENSI – SED-Erdbebenforschung zu Schweizer Kernanlagen“ project.

Realistic modeling of earthquake ground motions can be achieved only if the causative fault and the medium where waves propagate are described accurately. In earthquake scenario simulations for Switzerland, we combine state-of-the-art dynamic rupture along irregular fault surfaces and wave propagation in complex heterogeneous media at high frequency. Besides ordinary faulting due to accumulation of tectonic stress, we consider fault rupture induced by human activities, such as fluid injection. In such broadband simulations, the interaction between the seismic wave field and the medium occurs at multiple levels and scales. Therefore, we couple high-resolution 3D basin models with random velocity heterogeneity and complex topography to correctly model resonance, mode conversion and scattering of seismic waves. Along with source and path effects, near-surface site conditions represent an important factor controlling ground motions since soft sediments can significantly amplify the shaking observed during an earthquake. Depending on the level of input ground motion, liquefiable soils have the potential to generate excess water pressure resulting in high-frequency acceleration pulses. Advanced constitutive models of liquefiable soils require the knowledge of so-called dilatancy parameters that describe the potential to generate excess water pressure. These parameters can be determined from field observations by analyzing cone penetration test (CPT) measurements. Accurate modeling of liquefiable soils is essential to reliable prediction of earthquake site response and can help explore the physical limits of ground motion.

Project Leader at SED

Donat Fäh

SED Project Members

Walter Imperatori, Marco Pilz, Jan Burjanek

Involved Institutions

San Diego Supercomputer Center

Funding Source

Swiss Federal Nuclear Safety Inspectorate – ENSI

Duration

2014-2018

Key Words

Ground motion, scattering, non-linearity, site effects, CPT

Research Field

Engineering Seismology

Publications

Imperatori, W. and Mai, M. (2015). The role of topography and lateral velocity heterogeneities on near-source scattering and ground-motion variability. Geophys. J. Int. 202(3), 2163-2181. doi: 10.1093/gji/ggv281

Gallovic, F., Imperatori, W. and Mai, M. (2015). Effects of three-dimensional crustal structure and smoothing constraint on earthquake slip inversions: Case study of the Mw6.3 2009 L’Aquila earthquake. J. Geophys. Res. Solid Earth. 120(1), 428–449. doi: 10.1002/2014JB011650

Roten, D., Olsen, K.B., Day, S.M. and Fäh, D.  (2014). Expected seismic shaking in Los Angeles reduced by San Andreas fault zone plasticity. Geopys. Res. Lett. 41(8), 2769-2777. doi: 10.1002/2014GL059411

Roten, D., Fäh, D. and Bonilla, L.F. (2014). Quantification of cyclic mobility parameters in liquefiable soils from inversion of vertical array records. Bull. Seism. Soc. Am. 104(6), 3115-3138. doi: 10.1785/0120130329