Seismic moment tensor and focal mechanism for earthquake of February 22, 2024 in eastern Slovakia (12:54:15 UTC, 21.75E°E, 49.03°N, depth 9 km, ML3.0)

Authors

  • D.V. Malytskyy Carpathian Branch of S. Subbotin Institute of Geophysics of NASU, Lviv, Ukraine; Institute of Rock Structure and Mechanics of the Czech Academy of Sciences,, Ukraine
  • L. Fojtikova Institute of Rock Structure and Mechanics of the Czech Academy of Sciences, Prague, Czech Republic, Czechia
  • J. Malek Institute of Rock Structure and Mechanics of the Czech Academy of Sciences, Prague, Czech Republic, Czechia
  • O.A. Astashkina Carpathian Branch of S. Subbotin Institute of Geophysics of National Academy of Sciences of Ukraine, Lviv, Ukraine, Ukraine
  • A.R. Gnyp Carpathian Branch of S. Subbotin Institute of Geophysics of National Academy of Sciences of Ukraine, Lviv, Ukraine, Ukraine
  • M.S. Dobushovskyy Carpathian Branch of S. Subbotin Institute of Geophysics of National Academy of Sciences of Ukraine, Lviv, Ukraine, Ukraine
  • R.M. Pak Carpathian Branch of S. Subbotin Institute of Geophysics of National Academy of Sciences of Ukraine, Lviv, Ukraine, Ukraine
  • M.O. Melnyk Lviv Centre of Institute of Space Research of National Academy of Sciences of Ukraine, Lviv, Ukraine, Ukraine
  • V.G. Nikulins SIA Geo Consultants, Riga, Latvia, Latvia
  • V.V. Ignatyshyn S.I. Subbotin Institute of Geophysics, National Academy of Sciences of Ukraine, Kiev, Ukraine, Ukraine

DOI:

https://doi.org/10.24028/gj.v47i2.322470

Keywords:

focal mechanisms, waveform inversion, seismic moment tensor, direct waves, seismic stations, earthquakes

Abstract

The accuracy of the focal mechanism solution can depend very significantly on the number of stations used, especially in the case of weak earthquakes and sparse networks. We describe the procedure for retrieving the seismic moment tensor for the earthquake of February 22, 2024, which happened in Eastern Slovakia, using a limited number of seismic stations. We use records from only two stations of the Slovakian network: sk19 (49.25 °N, 21.93 °E) and sk20 (49.21 °N, 21.61 °E). The moment tensor inversion of high-frequency seismogram data in this study is based on a point source approach using the matrix method for the direct waves. The process involves generating records in displacements using the frequency and wave-number integration technique for an elastic horizontally layered medium. A method is presented for moment tensor inversion of only direct P- and S-waves, which is less sensitive to path effects modelling than reflected and converted waves, significantly improving the method’s accuracy and reliability. The location and origin time of the event are considered known. Based on forward modelling, a numerical technique is developed for the inversion of observed waveforms for the of moment tensor M(t) components obtained by generalized inversion.

References

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Published

2025-04-07

How to Cite

Malytskyy, D., Fojtikova, L., Malek, J., Astashkina, O., Gnyp, A., Dobushovskyy, M., Pak, R., Melnyk, M., Nikulins, V., & Ignatyshyn, V. (2025). Seismic moment tensor and focal mechanism for earthquake of February 22, 2024 in eastern Slovakia (12:54:15 UTC, 21.75E°E, 49.03°N, depth 9 km, ML3.0). Geofizicheskiy Zhurnal, 47(2). https://doi.org/10.24028/gj.v47i2.322470

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