Modern Geodynamics and Focal Mechanisms of Earthquakes near the Bushehr Nuclear Power Plant
A method for determining the focal mechanisms of earthquakes using the S-wave polarization direction for weak close seismic events is developed based on the detailed seismological studies carried out by the seismological expedition of the Institute of Physics of the Earth of the Russian Academy of Sciences in 1999–2001 near the Bushehr nuclear power plant (NPP) in Southern Iran. The results of the reconstruction of such determinations are compared with the focal mechanisms of strong earthquakes determined in ISC catalogs using the standard method and with modern concepts of tectonic deformation of the earth’s crust in a wide vicinity of the region under consideration. It has been established that this reconstruction is in good agreement with both the typification of movements in the foci of strong earthquakes and modern concepts about the nature of the deformation of the earth’s crust within the observation network. This allows us to recommend this method for reconstructing focal mechanisms in other regions.
Keywords:tectonic deformations geodynamics focal mechanisms of earthquakes kinematics of seismotectonic deformation
This work was supported by the Institute of Physics of the Earth of the Russian Academy of Sciences.
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