Evaluation and comparative analysis of stress and deformations in seismic hazard zones in Bulgaria and adjacent lands

Main Article Content

Valentina Nikolaeva Protopopova
https://orcid.org/0000-0002-1776-0220
Emil Alexandrov Botev

Abstract

In this paper an attempt to elucidate the geodynamic situation in Bulgaria and adjacent lands from a seismological point of view is proposed. The fault plane solutions of 418 earthquakes and corresponding stresses and deformations are also analyzed. For the purposes of the quantitative stress and strain modeling, a seismic zonation is carried out and the Bulgarian territory and surroundings are divided in nine seismic hazard zones. The main seismological and focal mechanisms characteristics for each zone are presented. The stress tensors for the zones/fault systems are calculated by inversion of the focal mechanisms data using the technique of Gephart [1990]. The released strain is computed by means of the moment tensors of focal mechanisms according to the relation of Kostrov [1974]. In general, the obtained mean strain tensors show some agreement with the calculated mean stresses. Several local discrepancies and the whole geodynamic situation are analyzed in the light of some present tectonic hypotheses. On the basis of the analysis of the seismicity, stress and deformation on the territory of North Balkans are presented.

Article Details

How to Cite
Protopopova, V. N. and Botev, E. A. (2020) “Evaluation and comparative analysis of stress and deformations in seismic hazard zones in Bulgaria and adjacent lands”, Annals of Geophysics, 63(2), p. GD224. doi: 10.4401/ag-8125.
Section
Geodynamics and Tectonophysics
Author Biographies

Valentina Nikolaeva Protopopova, National Institute of Geophysics, Geodesy and Geography – Bulgarian Academy of Sciences

Department of seismology and seismic engineering, Assistant Professor

Emil Alexandrov Botev, National Institute of Geophysics, Geodesy and Geography – Bulgarian Academy of Sciences

Department of seismology and seismic engineering, Professor