Determining the local earthquake origin time and Vp/Vs ratio using the Wadati diagram

Authors

  • Uyanga Bayaraa Seismological department, Institute of Astronomy and Geophysics, Mongolian Academy of Sciences, Ulaanbaatar, Mongolia https://orcid.org/0009-0002-3236-4135
  • Munkhsaikhan Adiya Institute of Astronomy and Geophysics, Mongolian Academy of Sciences, Ulaanbaatar, Mongolia
  • Daariimaa Badarch Institute of Astronomy and Geophysics, Mongolian Academy of Sciences, Ulaanbaatar, Mongolia

DOI:

https://doi.org/10.5564/mjag.v12i1.5204

Keywords:

Wadati diagram, velocity ratio (Vp/Vs)

Abstract

Seismological research encompasses a wide range of studies related to earthquakes. Determining the origin time, spatial distribution, and seismic velocity ratios of earthquakes occurring in a specific region, as well as compiling an earthquake database, provides fundamental and essential information for evaluating the spatial occurrence, recurrence patterns, and seismic hazards of that region. In this study, the origin times and velocity ratios of earthquakes were determined using the Wadati diagram method. The analysis was based on the recorded arrival times of P-waves and S-waves at seismic stations for 371 earthquakes that occurred within the territory of Mongolia and surrounding border regions. The results of the study indicate that the average seismic velocity ratio (Vp/Vs) was calculated to be 1.72.

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References

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Published

2025-12-30

How to Cite

Bayaraa, U., Adiya, M., & Badarch, D. (2025). Determining the local earthquake origin time and Vp/Vs ratio using the Wadati diagram. Mongolian Journal of Astronomy and Geophysics, 12(1), 65–70. https://doi.org/10.5564/mjag.v12i1.5204

Issue

Vol. 12 No. 1 (2025)

Section

Research Articles

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Copyright (c) 2025 Uyanga Bayaraa, Munkhsaikhan Adiya, Daariimaa Badarch

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