DEEP STRUCTURE OF THE SCYTHIAN-URAL SEISMOGENERATING ZONE

The Scythian-Ural seismogenerating zone is associated with neoseismic dislocations trending northeast similarly to the Cyprus-Caucasus neoseismic left-lateral shear belt. This zone exhibits the occurrences of seismicity. To assess the conditions for the occurrence of seismic events within the Scythian-Ural zone it is necessary to know its deep structural features. Accordingly, the purpose of the present study was to investigate the deep structure of earthquake source zones based on the analysis and generalization of all geophysical data available. Based on the integrated geophysical data, there have been determined the deep structural features of the Scythian-Ural neoseismic dislocation zone. It is shown that the stress-strain state of the Earth’s crust and mantle within this zone is regionally caused by the horizontal compression forces of the Caucasus and the Urals folded systems, which led to the formation of a system of dislocations trending northeast from the Scythian Plate to the Urals folded system. Within the Scythian-Ural neoseismic dislocation zone, there have been identified heterogeneities caused by the decompaction of the Earth’s crust and mantle. The dynamics of decompacted rock complexes in local areas was formed under a combined effect of horizontal compression forces and tectonic dislocations, with the latter inherited from the lower crust and upper mantle. These dislocations are associated with source zones of strong earthquakes with a magnitude of 5 or higher. In the future, the results of the research can be used to identify potential strong earthquake sources within the studied areas.

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