Natural Hazards

, Volume 42, Issue 3, pp 493–514 | Cite as

Tectonic stress, seismicity, and seismic hazard in the southeastern Carpathians

  • Alik Ismail-ZadehEmail author
  • Vladimir Sokolov
  • Klaus-Peter Bonjer
Original Paper


Intermediate-depth earthquakes in the Vrancea region occur in response to stress generation due to descending lithosphere beneath the southeastern Carpathians. In this article, tectonic stress and seismicity are analyzed in the region on the basis of a vast body of observations. We show a correlation between the location of intermediate-depth earthquakes and the predicted localization of maximum shear stress in the lithosphere. A probabilistic seismic hazard assessment (PSHA) for the region is presented in terms of various ground motion parameters on the utilization of Fourier amplitude spectra used in engineering practice and risk assessment (peak ground acceleration, response spectra amplitude, and seismic intensity). We review the PSHA carried out in the region, and present new PSHA results for the eastern and southern parts of Romania. Our seismic hazard assessment is based on the information about the features of earthquake ground motion excitation, seismic wave propagation (attenuation), and site effect in the region. Spectral models and characteristics of site-response on earthquake ground motions are obtained from the regional ground motion data including several hundred records of small and large earthquakes. Results of the probabilistic seismic hazard assessment are consistent with the features of observed earthquake effects in the southeastern Carpathians and show that geological factors play an important part in the distribution of the earthquake ground motion parameters.


Intermediate-depth earthquake Vrancea Seismic intensity Peak ground acceleration Probabilistic seismic hazard assessment 



Carpathian Arc Lithospheric X-Tomography


Fourier amplitude spectra


Horizontal-to-vertical Fourier spectral ratio


Intensity scale


Peak ground acceleration


Probabilistic seismic hazard assessment


Response spectra amplitude


Very hard rock



The constructive comments and suggestions of two anonymous reviewers are gratefully acknowledged. We are very thankful to M. Martin and F. Wenzel for useful discussions on the regional seismic tomography and seismic hazard. This research was supported by the Collaborative Research Center SFB 461 “Strong Earthquakes”, French Ministry of Research, and Russian Academy of Sciences.


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Copyright information

© Springer Science+Business Media, Inc. 2007

Authors and Affiliations

  • Alik Ismail-Zadeh
    • 1
    • 2
    • 3
    Email author
  • Vladimir Sokolov
    • 1
  • Klaus-Peter Bonjer
    • 1
  1. 1.Geophysikalisches InstitutUniversität KarlsruheKarlsruheGermany
  2. 2.Institut de Physique du Globe de ParisParisFrance
  3. 3.International Institute of Earthquake Prediction Theory and Mathematical GeophysicsRussian Academy of SciencesMoscowRussia

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