Research

The institute's research activities focus on seismic structural studies, monitoring seismology, developing methods related to monitoring seismology and earthquake research in the Fennoscandian region. Seismic structural studies and regional earthquake research serve both geophysical and geological basic research in the Fennoscandian region. The Institute of Seismology is responsible for seismic monitoring in the field of civil protection and nuclear test control based on international agreements.

Seismic monitoring is one of the four technologies used by the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification regime to monitor compliance with the Treaty. The objective of seismic monitoring is to detect and locate underground nuclear explosions and to distinguish them from other seismic events that happens daily, such as earthquakes.

The PCA project covers the activities that the Institute of Seismology will carry out in the operation and maintenance of the IMS primary seismic station FINES (PS17), Finland. The purpose of the project is to guarantee that the station meets the requirements of the International Monitoring System with respect to operational performance, technical characteristics, data availability and reliability.

CTBTO: PCA for IMS Primary Seismic Station PS17/FINES

CTBTO website

Leader: Jari Kortström, MSc

In the earthquake seismology group we focus on earthquakes, fault zone structure, modes of deformation along fault zones, and earthquake and fault zone interaction and triggering mechanisms on a local and regional scale. We analyze seismic waves emanated from earthquakes, but extract also information from the ambient seismic wave field or noise. The research depends on the application and development of analysis techniques for estimating earthquake source parameters, for structural imaging and for the monitoring of time dependent changes in crustal and fault zone materials on time scales ranging from seconds to years. Our work is based on processing large seismic data sets (big data at its very best) and has thus multiple connections to physics and atmospheric sciences (wave propagation), mathematics and medical imaging (inverse problems), and computer science (code development).

Seismic imaging constitutes a fundamental building block of Earth Science research that is practiced by a large community and applied across many scales. The analogy between ultrasonic medical sensors and spatially dense seismic arrays opens up an alternative way for seismic imaging that differs from tomographic methods. We research to what extend the near-field phenomenon referred to as “focal spot” in acoustics can provide simultaneous estimates of the local seismic velocity structure, azimuthal anisotropy, and proxies for intrinsic attenuation without solving an inverse problem.

Modern societies critically depend on sustainable natural resource production and renewable energy sources. Geothermal energy is in many ways an advantageous energy source for local heat and electricity production in densely populated areas. The low environmental impact compared to non-renewables, and the independence on atmospheric, climatic or weather patterns that severely constrain wind and solar technologies have led to a growing interest and use of geothermal energy production. The development of deep geothermal energy projects is, however, not without risks. Our group is dedicated to contribute to a sustainable and safe use of deep geothermal energy. We have been collecting an outstanding data set during the stimulation of the St1 Enhanced Geothermal System between 5 and 6 km depth below Otaniemi, Espoo, in summer 2018. The analysis of the induced earthquakes, and of the altered rock properties will help to mature the application of geothermal energy use in Finland. We target a comprehensive understanding of the rock types and their seismic response, their permeability and geochemical properties, and the location of faults; of the local temperature profile, the stress regime and stress orientations; and of the hydrological situation.

Leader: Gregor Hillers, Associate Professor

The European Plate Observation System (EPOS) is coordinating the integrated use of data, models and facilities from spatially separated Solid Earth research infrastructure (RI). The Finnish national initiative is a joint proposal of the Univ. Helsinki and Oulu, FGI, FMI, GTK, VTT MIKES and CSC. The RI consists of permanent and portable seismic and geodetic stations, magnetic observatories, portable electromagnetic arrays, geodynamic modeling and geophysical laboratories. The operation and maintenance of the RI is funded through host organization's annual budget. Upgrading and expanding of the RI and databanks, special campaigns are funded by grants. EPOS is implementing the long term strategic goals of the geoscientific institutes: leading role European Earth processes, natural hazards and resources studies, and easy access to large datasets.

Leader: Annakaisa Korja, Research director

FIN-EPOS website

EPOS in TUHAT database

People

Niina Junno, MSc

In the FLEX-EPOS RI project a national pool of geophysical instruments and multi-disciplinary geophysical superstations is created to solve fundamental research questions in seismology, geomagnetism and geodesy. FLEX-EPOS comprises infrastructure and pool of instruments, which can be used in large numbers in various study areas for short- and long-term data collection. The instrument pool is created, maintained and operated  in a national co-operation with four universities (Helsinki, Oulu, Turku, Aalto) and three research institutes (GTK, VTT, FGI). The greatly expanded observational capability will contribute to science by providing massive new datasets, observations and results, and strengthen and extend the role of FInland in the European Plate Observing System (EPOS).

Learder: Ilmo Kukkonen, Professor in solid earth geophysics

People

Timo Tiira, Research director

Niina Junno, MSc

Tommi Vuorinen, MSc

Members of the Helsinki University Geodynamics Group (HUGG) study processes involved in deformation of the Earth’s lithosphere. Our research focuses on quantifying the kinematics and dynamics of the tectonic, geomorphic and geodynamic processes that shape Earth’s outer rigid layer primarily using numerical modelling. Our cutting-edge predictive and interpretative numerical tools are connected with observations from the field, and geochronological, geophysical or remote sensing data. We are also actively involved in teaching in the Bachelor’s programme in Geosciences, the Master's programme in Geology and Geophysics, and the new Bachelor’s of Science in English programme that will launch in 2019.

Leader: David Whipp, Associate Professor

More information about the HUGG can be found on the HUGG wiki site.

We develop and evaluate new methods in monitoring seismology. The research is focused in developing automatic detection, location and event classification flows. Utilizing machine learning methods in the center of our research.

Projects

Auto­matic seis­mic event clas­si­fic­a­tion

Auto­matic iden­ti­fic­a­tion of seis­mic phases

Monitoring the monitoring

People

Timo Tiira, Research director

Jari Kortström, MSc

Marja Uski, Phil. Lic.

Kati Oinonen, MSc

Katriina Arhe, MSc

Toni Veikkolainen, PhD

David Whipp, Associate professor

Tuija Luhta, MSc

Tommi Vuorinen, MSc

Nordic EPOS - A FAIR Nordic EPOS Data Hub – is a consortium of the Nordic geophysical observatories delivering on-line data to EPOS Thematic Core Services. Nordic EPOS consortium comprises the Universities of Helsinki (UH), Bergen (UiB), Uppsala (UU), Oulu (UOULU) and Geological Survey of Denmark and Greenland (GEUS) and Icelandic Meteorological Office (IMO). The hub’s main objectives are to: a) increase awareness and usage of multi-disciplinary Nordic EPOS data, data products, software and service for scientific and societal problem solving, b) increase the amount of, and access to, Nordic FAIR data, and c) support data management of new data types and scientific expertise needed for safe and sustainable societies in Nordic countries and especially in the Arctic region.

Learder: Annakaisa Korja, Research director

Nordic EPOS website

Nordic EPOS in Tuhat database

People

Gregor Hillers, Associate Professor

Niina Junno, MSc

Tommi Vuorinen, MSc

Our research is focused on determining source mechanisms for recent earthquakes in Finland, on identifying active faults associated with earthquakes, and on gaining informa­tion on the in situ stresses causing earthquakes. We also develop automatic methods for analysing seismic events recorded by a sparse regional network.

Seismic hazard studies associated with nuclear power plants and enhanced geothermal systems are one of the recent topics.

Projects

Pre-instrumental earthquakes

Vyborg Rapakivi batholith seismicity

People

Päivi Mäntyniemi, PhD

Marja Uski, Phil. Lic.

Gregor Hillers, Associate Professor

Tommi Vuorinen, MSc

Timo Tiira, Research director

Tuija Luhta, MSc

In the Seismic risk - Mitigation of induced seismic risk in urban environments - project UH-VTT-GTK research consortium is studying, how to mitigate induced seismic risk associated with deep geothermal power stations in the Helsinki capital region. Small low magnitude earthquakes pose a risk to the critical tremor sensitive infrastructure such as hospitals, data centers, underground construction. Risk can be mitigated with transparent permitting, seismic monitoring and regional planning. The project will publish a set of seismic hazard maps of Finland and assess the potential impact of seismic waves on different parts of the capital area via 3D models: shear wave tomography, conceptual soil and bedrock model. In addition the project will study the different roles the national, regional and municipal governance in the wicked permitting processes. It will also study what sort of information and at what level of detail do the authorities need on induced seismicity and associated risks.

PI: Annakaisa Korja

People

Timo Tiira, Research Director

Gregor Hillers, Associate Professor

Päivi Mäntyniemi, PhD

Toni Veikkolainen, PhD

Niina Junno, MSc

Tommi Vuorinen, MSc

Kati Oinonen, MSc

Annukka Rintamäki, MSc

We study structure of the Lithosphere in all scales.

Projects

KOKKY Deep Seismic Sounding in Tuhat Database

SOFI Deep Seismic Sounding in Tuhat Database

Seismicity and 3D seismic velocity structure in Kuusamo area

Seismicity, faults and 3D seismic velocity structure in Pyhäjoki area

Monitoring Network in Pyhäjoki

Tomographic imaging of seismic velocity structure beneath southern and central Finland

A tomographic crustal velocity model of the central Fennoscandian shield

Hyvönen, T., Tiira, T., Korja, A., Heikkinen, P., Rautioaho, E., SVEKALAPKO Seismic Tomography Working Group & Komminaho, K. 2007 julkaisussa : Geophysical Journal International. 168, 3, s. 1210-1226

WARR seismic profiling in Ukraine

COGITO-MIN in Tuhat Database

COGITO-MIN project website

People

Timo Tiira, Research director

Annakaisa Korja, Research director

Kari Komminaho, Msc

Toni Veikkolainen, PhD

 

Below are some examples of potential thesis topics related to seismology or supervised by personnel from the institute of seismology.

  1. Hydrothermally altered mineralized systems: Seismic reflection properties of rocks (Kukkonen, Koivisto)
  2. Processing and analysis of seismic reflection data in exploration and mining camps (Koivisto, Kukkonen)
  3. Induced seismicity in enhanced geothermal systems (Kukkonen, Korja)
  4. Data processing and interpretation of seismic data from Siilinjärvi phosphate mine for mine planning (Koivisto)
  5. Applicability of Open quake software to Finnish conditions (Mäntyniemi, Seismology)
  6. Automatic assessment of seismic intensity for felt earthquakes in Finland (Mäntyniemi, Seismology)
  7. Harmonization of internet macroseismology in Fennoscandia (Mäntyniemi, Nordic colleagues)
  8. Several projects associated with the analysis of seismic data collected by 100+ stations around the 2018 geothermal reservoir stimulation in Otaniemi/Espoo (Hillers, Seismology)
  9. Several projects associated with crustal and fault zone monitoring and imaging using ambient noise correlations (Hillers, Seismology)
  10. Refocusing and time reversal (Hillers, Seismology)
  11. Automatic identification of seismic signals from frost events using deep learning (Tiira, Seismology)
  12. Detection and identification of glacier based seismic signals in Antarctica using unsupervised machine learning (Tiira, Seismology)
  13. Automatic detection of seismic events in urban areas, comparison of methods (Tiira, Seismology)
  14. Seismic signal onset estimation by combining different methods and machine learning (Tiira, Seismology)
  15. Study of dissimilarities of microearthquakes in concise earthquake populations with self-organizing maps (Tiira, Seismology)
  16. Influence of seismic station locations on data acquired and threshold event size, Kouvola, Finland (Vuorinen, Oinonen, Seismology)
  17. Ablative subduction in the Andes: An alternative mechanism for removal of mantle lithosphere? (Whipp)
  18. Quantifying rates of bedrock landsliding in mountainous regions and their implications for landscape erosion (Whipp)
  19. Effects of orographic precipitation on mountain evolution in 3D (Whipp)
  20. Where does landslide-derived sediment go and how long does it take? (Whipp)
  21. Mapping erosion in steep mountain landscapes using detrital thermochronology (Whipp, international colleagues)
  22. Paleoproterozoic plateaus: Implications for lithospheric evolution and crustal metamorphism (Whipp)
  23. Ground-motion characteristics of induced seismicity compared to natural earthquakes (Vuorinen)
  24. Radiogenic heat production model of the lithosphere based on geochemistry and seismic data (Kukkonen, Veikkolainen)
  25. Geoneutrinos and radiogenic heat production of the Earth (Kukkonen, Veikkolainen)
  26. Tectonothermal environment of the Wiborg rapakivi batholith (Veikkolainen)
  27. Geophysical properties of the Pyhäsalmi area (Veikkolainen)
  28. Low temperature thermochronology Fission track & He-U-Th-methods (Whipp, Kukkonen)
  29. Modeling of thermochronological data (Whipp, Kukkonen)

Below are some examples of the recent thesis titles related to the Institute of Seismology.

  1. Metiäinen, Nelli, 2019: South American subduction zone processes : Visualizing the spatial relation of earthquakes and volcanism at the subduction zone. Master's thesis.
  2. Luhta, Tuija, 2019: Petrophysical properties of the Kylylahti Cu-Au-Zn sulphide mineralization and its host rocks. Master's thesis.
  3. Laakso, Viveka, 2019: Testing of Reflection Seismic, GPR and Magnetic Methods for Mineral Exploration and Mine Planning at the Siilinjärvi Phosphate Mine Site in Finland. Master's thesis.
  4. Väkevä, Sakari, 2019: Using Three-Component Data for Seismic Interferometry Studies at the Kylylahti Mine, Eastern Finland. Master's thesis.
  5. Pinola, Hannu, 2019: Maatutkaprofiilien syvyyskalibrointi CMP-luotauksella esimerkkikohteissa Helsingissä ja Hollolassa. Master's thesis.
  6. Schütt, Jorina, 2018. 3D dynamics of crustal deformation along the western Andean margin. Doctoral thesis.
  7. Aalto, Aleksi, 2017. Development of a Web GIS Application and Data Management Practices for Integrating Geological and Geophysical Data. Master's thesis.
  8. Tuomi, Hilkka, 2016. Seismic forward modelling constraints for seismic ore exploration at the Kylylahti Cu-Co-Zn-Ni-Ag-Au sulfide deposit. Master's thesis.
  9. Vuorinen, Tommi, 2016. New Fennoscandian Empirical Ground Characterization Model. Master's thesis.
  10. Lammi, Hannu, 2015. Numerical Modelling of Mid-Crustal Flow Applied to Svecofennian Orogeny. Master's thesis.
  11. Heinonen, Suvi, 2013. Seismic reflection profiling for massive sulfide exploration in Finland. Doctoral thesis.
  12. Hellqvist, Niina, 2013. FIRE 2 ja 2a -linjojen rakenteen mallintaminen seismistä attribuuttianalyysiä apuna käyttäen. Master’s thesis.
  13. Koskinen, Paula, 2013. Orientation of faults and their potential for reactivation in the present stress field in Finland. Master’s thesis.

Ongoing theses related to institute of seismology include:

  1. Vuorinen, Tommi: Analysis of induced seismicity of Otaniemi Enhanced Geothermal System. Doctoral thesis.
  2. Junno, Niina: Seismic properties of ores and structures controlling ore deposits: new insights from data mining and seismic forward modeling. Doctoral thesis.
  3. Tsarsitalidou, Christina: Focal spot imaging applied to data from dense seismic arrays. Doctoral thesis.
  4. Rintamäki, Annukka: Geological and geophysical constraints on induced seismicity related to enhanced geothermal systems. Doctoral thesis.
  5. Luhta, Tuija: Vyborg Rapakivi batholith seismicity. Doctoral thesis.
  6. Hällsten, Jennifer: Methodological consideration of macroseismic data in Finland: revisiting the Lappajärvi earthquake (ML 3.8) February 17, 1979. Master’s thesis.
  7. Rantanen, Aleksi: Influence of arc magmatism on crustal temperatures and strength in continental subduction zones. Master’s thesis.
  8. Yijun Wang: Tectonics of strain partitioning in the southern Andes of Chile. Master’s thesis.
  9. Ylä-Mella, Lotta: Forward and inverse modelling of cosmogenic radionuclides in high-latitude glaciated landscapes. Master’s thesis.
  10. Arola, Eemil: Local magnitude estimates for earthquakes induced during a geothermal reservoir stimulation. Master's thesis.
  11. Voutilainen, Ahti: GMPE for the capital region of Finland, and comparing natural and induced seismic events. Master's thesis.
  12. Hanski, Ida-Maria: Finnish National Seismic Network: location errors, detection thresholds and network vulnerability. Master's thesis.

Publications related to the Institute of Seismology are found in Tuhat research database.

List of publications prior to 2010 can be found here.