Department of Seismotectonics

Department of Seismotectonics is concerned with studies of natural seismic phenomena linked to dynamic and tectonic development of structures in the earth crust, particularly in its upper part, and with studies of seismic phenomena induced by anthropogenic activities. The department develops applications for evaluations of geophysical monitoring, as well as monitoring devices and methodology for monitoring seismicity in earth crust and of its impact on stability of rock environment.

1. SEISMIC MONITORING 
The Department of Seismotectonics participates in operating permanent and temporary seismic stations distributed in several countries (the Czech Republic, Slovakia, Iceland, Ethiopia). Most of the stations belong to the European Plate Observing System (EPOS). The data are used for basic research and monitoring seismic activity to aid in seismic-hazard issues associated with important infrastructure.

2. SEISMIC AND VOLCANIC HAZARD
The seismic activity in the Czech Republic is moderate. However, significant seismic hazard is connected with strong earthquakes in the Eastern Alps. The department develops new methods for seismic hazard assessment of nuclear installations in the Czech Republic. Volcanic hazard is also an important research element with efforts made in developing models or scenarios of magma flow and magma behavior in low pressure conditions close to the surface and inside scoria cones.

3. SURFACE WAVES
A significant part of the research focuses on surface waves which are robust data that can be used to analyze the structure of near-surface zones not only on Earth but even on the Moon. Major efforts are directed toward inventing and validating new methodologies in both computational aspects and practical considerations related to field procedures and measurements.

4. INDUCED SEISMOLOGY
Study of microseismicity and induced seismicity includes case stories, mechanisms of microearthquakes, statistical analysis of induced seismicity and methodological aspects of the attenuation from weak events. It is critical  to find differences between natural and induced seismicity and geomechanically interpret observations in order to better understand the relationship between fluid injection and reservoir response.

International Cooperation

Institute of Methodologies for Environmental Analysis (IMAA) of the National Research Council of Italy (CNR) Tito
Italy

Cooperation with the Institute of Methodologies for Environmental Analysis (IMAA) of the National Research Council of Italy (CNR) (based on bilateral cooperation between the Czech and Italian Academy of Sciences) on improving the detection and localization of weak earthquakes in the area of High Agri Valle and oil fields in North America, velocity and attenuation model inversion (Wcislo et al., 2018) and differentiation between natural earthquakes and earthquakes triggered/induced by human activity (Vlček et al., 2018; Telesca et al., 2016).

University of Trieste(Università degli Studi di Trieste)
Italy

The methodology for analysis of surface waves was applied in the framework of informal cooperation with the University of Trieste (Italy) [some results were published in a conference proceeding and a chapter of the book Efficient Joint Analysis of Surface Waves and Introduction to Vibration Analysis: Beyond the Clichés (to be published by Springer).

New Mexico Highlands University
USA

Research on visualization of volcanic structures and magma emplacement. International field courses for students focused to volcanologya and visualization of inner structure of volcanoes using geophysical methods.

Technological University Bergakademie Freiburg
Germany

Cooperation with TU Bergakademie Freiberg, Geological Department, Head of the Department prof. Lothar Ratchbacher. In June and July 2018, a team member RNDr. Lucie Novakova, Ph.D. got a scholarship funded by DAAD. They studied thermochronological evolution of the Naab area (W part of the Bohemian Massif) using fission-track analysis.

United States Geological Survey
USA

Project GAP210/10/0925 "Rotational components of seismic waves for local shallow earthquakes and artificial sources" (2010-2013, GA0/GA)


Continuation of the project to the Ministry of Education-AMVIS "the six-continuous monitoring of seismic swarms in the areas of Long Valley Caldera and The Geysers, California."

Progseis, s r.o
Slovakia

Monitoring and analysis of seismic phenomena.

Petroleum Institute , Abu Dhabi
United Arab Emirates

Analysis of detection-induced seismicity at injection of wastewater

University of Memphis, Tennessee
USA

A bilateral project was formulated together with Dr. Charles Langstone, Center of Earthquake Research and Information, University of Memphis.

Arba Minch University
Ethiopia

Student mentoring, geohazard monitoring. Development projects financed by the Czech Development Agency.

King Saud University, Riyadh
United Arab Emirates

The research line about the joint acquisition and analysis of surface waves (Holistic Analysis of Surface Waves) was/is partly accomplished in cooperation with ISPRA and, during the March 2015 - March 2016 period, in the framework of the Visiting Professor Program of the King Saud University (Riyadh, Saudi Arabia). The implemented methodology was considered also for the Bachelor and PhD theses of two students (one from Italy/Ghana, the other from Iran).

Iceland Geosurvey ÍSOR
Island - Reykjanes Peninsula Region

Under the project "Earthquake swarms and their triggering mechanisms in diverse tectonic environments (Bohemian Massif, Mid-Atlantic Ridge, Western Alps)" we set up a seismic network on Reykjanes peninsula in the southeast Iceland. All 15 stations were placed during August/September of 2013 to monitor earthquake activity in this region for at least 2 years.
Measured data allow us to study the seismic source and to compare the seismic activity with other regions of earthquake swarms.
In 2010 we initiated a cooperation with Icelandic Met Office and started a common comparative study of West Bohemian and South Icelandic earthquakes. We analyzed catalogues of over 20 years of observations and we found out that the swarms in West Bohemia and South Iceland are alike.

Grant project reference: GAP210/12/2336

(Eidgenössische Technische Hochschule Zürich-ETH)
Switzerland

The characterization of building vibrations through an analysis of microtremor data (see GHM techniques) was accomplished thanks to cooperation with a Swiss company (www.roXplore) and a researcher from the Institute for Geotechnical Engineering, ETH Zürich, Switzerland.

The Earth Science Institute of the Slovak Academy of Sciences
Slovakia

Monitoring and analysis of seismic phenomena.

C3RN - Central and Eastern Europe Earthquake Research Network
Europe

An association of countries for improving the monitoring of seismic activities in the border regions and to enhance the collaboration between countries and seismological institutions in Central and Eastern Europe.

Geological Survey of Ethiopia
Ethiopia

Geological mapping, mapping of geohazards and their mitigation. Development projects financed by the Czech Development Agency.

Institute of Earth Sciences, Academia Sinica, Taipei
Taiwan

5D seismic monitoring and interpretation of the seismicity in the Hualien region at East coast of Taiwan.

Institute of Geology and Geophysics of the Chinese Academy of Sciences,Beijing, China
China

Cooperation with prof. Yibo Wang and his team.

Institute of Geophysics, Polish Academy of Sciences (Instytut Geofizyki Polskiej Akademii Nauk, IGF PAN), Warszawa
Poland

Developing and application of the methodology of active/passive source structural imaging supplemented by the work related to seismic signal denoising and monitoring.

Institute for Environmental Protection and Research (Istituto Superiore per la Protezione e la Ricerca Ambientale - ISPRA), Rome
Italy

The research line about the joint acquisition and analysis of surface waves (Holistic Analysis of Surface Waves) was/is partly accomplished in cooperation with ISPRA and, during the March 2015 - March 2016 period, in the framework of the Visiting Professor Program of the King Saud University (Riyadh, Saudi Arabia). The implemented methodology was considered also for the Bachelor and PhD theses of two students (one from Italy/Ghana, the other from Iran).

Results

Heat extraction calculations for deep coaxial borehole heat exchangers: matrix analytical approach

2023

Matyska, C., and E. Zábranová (2023) Heat extraction calculations for deep coaxial borehole heat exchangers: matrix analytical approach, Geophys. J. Int. 235, 2323-2338, 
doi: 10.1093/gji/ggad367

MASW? A critical perspective on problems and opportunities in surface-wave analysis from active and passive data (with few legal considerations)

2023

The difference between the standard MASW (Multichannel Analysis of Surface Waves) approach, based on data obtained from a set of vertical geophones, and the analysis of data obtained from a single three-component (3 C) geophone has been demonstrated to provide more information and thus enable reliable shear-wave velocity profiles (VS profiles) to be efficiently obtained. This is possible because surface-wave analysis can be effectively carried out considering not phase velocities but group velocities, with the obvious benefit that while for the phase-velocity analysis multi-offset data are necessary, the definition of the group velocities can be accomplished from single-offset data (i.e. from the data of one single sensor).

Publication:
Dal Moro, G., (2023). MASW? A critical perspective on problems and opportunities in surface-wave analysis from active and passive data (with few legal considerations), Physics and Chemistry of the Earth, 130, 103369, doi: 10.1016/j.pce.2023.103369
 

Image
MASW
Fig. Field image from a palaeoseismological survey. The eroded bank where the simple site stratigraphy is clearly exposed: a soft-silt sequence lies over a series of gravel layers (mud-gravel contact).


 

Seismic lectures. Volume waves, surface waves, 2D sections and amplifications

2023

Dal Moro, G. (2023). Book: Lezioni di sismica (Onde di volume, di superficie, sezioni 2D e amplificazioni), Dario Flaccovio Editore, 248p., 166 color figures, 
ISBN 9788857911946.

New Velocity Structure of the Nový Kostel Earthquake-Swarm Region, West Bohemia, Determined by the Isometric Inversion

2023

Málek, J., Brokešová, J., and O. Novotný (2023) New Velocity Structure of the Nový Kostel Earthquake-Swarm Region, West Bohemia, Determined by the Isometric Inversion, Pure Appl. Geophys. 
doi: 10.1007/s00024-023-03250-w

Harmonic Seismic Wave Generator and Seismic Prospection Assembly

2023

Málek, J. (2023) Patent č. CZ 309648 B6, Generátor harmonických seismických vln a sestava pro seismickou prospekci

Surface waves as a cost-effective tool for enhancing the interpretation of shallow refraction seismic data

2023

Mazanec, M., and J. Valenta (2023) Surface Waves as a Cost-Effective tool for Enhancing the Interpretation of Shallow Refraction Seismic Data, Acta Geodyn. Geomater., 20, 3(211), 121-138, 
doi: 10.13168/AGG.2023.0012

Hydraulic injection tests in the pilot EGS borehole PVGT-LT1 in Litoměřice, Czechia

2023

Fischer, T., Vlček, J., Dědeček, P., Řihošek, J., Zimmermann, G., Holeček, J., Mazanec, M., Rukavičková, L., Janků, L., and E. Káldy (2023) Hydraulic injection tests in the pilot EGS borehole PVGT-LT1 in Litoměřice, Czechia, Geothermics, 115, 102805, 
doi: 10.1016/j.geothermics.2023.102805

Induced Microseismic Event with Strong Rupture Directivity and Superimposed Attenuation Effects

2023

During hydraulic fracturing of a shale reservoir in China, fracture directivity for an induced microseismic event of Mw~1.2 recorded by a dense surface star network of seismometers was determined For this purpose, We use the duration of the initial P-wave arrivals as a proxy for the peak frequency content The observed directional and offset dependence of the peak frequencies can be explained by superposed directionality effects of fast, possibly superstrong, fracture propagation and attenuation, allowing the orientation of the fracture plane of the event to be determined.

Publication:
Wcislo, M., Staněk, F., Gallovič, F., Wu, S., and I. Pšenčík (2023) Induced Microseismic Event with Strong Rupture Directivity and Superimposed Attenuation Effects, Seismol. Res. Lett. 94, 1455-1466,  doi: 10.1785/0220220229
 

Image
Induced Microseismic Event with Strong Rupture Directivity and Superimposed Attenuation Effects.
Fig. Induced microseismic effect of Mw~1.2, crack directivity: a) logarithms of observed peak frequencies, color scale corresponds to the range with 5% cut-off of highest/lowest values (3.51)/(4.20); b-c) logarithms of peak frequencies for the best-fit models of two different scenarios, considering (b) attenuation only (c) attenuation and directivity. The black star indicates the epicentre of the earthquake.


 

 

Heat extraction calculations for deep coaxial borehole heat exchangers: matrix analytical approach

2023

Matyska, C., and E. Zábranová (2023) Heat extraction calculations for deep coaxial borehole heat exchangers: matrix analytical approach, Geophys. J. Int. 235, 2323-2338
doi: 10.1093/gji/ggad367

Tools for the efficient analysis of surface waves from active and passive seismic data: exploring an NE-Italy perilagoon area with significant lateral variations

2022

Publication: Dal Moro, G., and J. Stemberk (2022). Tools for the efficient analysis of surface waves from active and passive seismic data: exploring an NE-Italy perilagoon area with significant lateral variations, Earth, Planets and Space, 74, 140 (2022), DOI: 10.1186/s40623-022-01698-z

Geophysical imaging of tree root absorption and conduction zones under field conditions: a comparison of common geoelectrical methods

2022

Publication: Majewski, R. S., Valenta, J., Tábořík, P., Weger, J., Kučera, A., Patočka, Z., and Čermák, J. (2022). Geophysical imaging of tree root absorption and conduction zones under field conditions: a comparison of common geoelectrical methods. Plant and Soil, 1-27, DOI: 10.1007/s11104-022-05648-2

Services

Sofware Download

Isometric Method

A novel algorithm called Isometric Method (IM) for solving smooth real-valued non-linear inverse problems has been developed. Model and data spaces are represented by using m+1 corresponding vectors at a time (m is the dimension of model space). Relations among vectors in the data space are set up and then transferred into the model space thus generating a new model. If the problem is truly linear, this new model is the exact solution of the inverse problem. If the problem is non-linear, the whole procedure has to be repeated iteratively. The basic underlying idea of IM is to postulate the distance in the model space in such a way that the model and data spaces are isometric, i.e. distances in both spaces have the same measure. As all model-data vector pairs are used many times in successive iterations, the number of the forward problem computations is minimized. There is no necessity to deal with derivatives. The requirement for the computer memory is low. IM is suitable especially for solving smooth medium non-linear problems when forward modelling is time-consuming and minimizing the number of function evaluations is topical. 
The code on this page is available in MATLAB. Please, do not hesitate to contact us for more information: malek [at] irsm.cas.cz.

 

Program Refract3D

Program for 3D seismic refraction data processing using the modified time-term method. 
download current version 0.2 | source code | manual | article Valenta and Dohnal (2007)

 

Program DISECA

 Matlab code for dispersive waveform calculation of the surface wave. Calculation is based on summation the particular frequency components with the introduction of phase shifts, corresponding to velocity dispersion and given distance from a seismic source.
download program

 

Program SVAL

A program for surface waves analysis, dispersion curves determination and inversion and their forward modeling.
download program

 

PhaseCorr

A program designed for surface wave phase velocity estimation using the two-station method.
download program

 

Program LocErr

A program for estimation of expected uncertainties of relative location in a network of seismic stations.
download program

Matlab code for visualization of outputs from program LocErr.
download program

 

MouseTrap: Python/ObsPy module for automated detection of long-period disturbances in seismic records. 
ISOLA-ObsPy: Python/ObsPy module for automated moment tensor inversion.