Geophysical research: article

Mining Institute of the Ural Branch of the Russian Academy of Sciences
Journal: Geophysical research
Tome: 22
Number: 2
Year: 2021
Pages: 5-30
UDK: 550.31+550.34+55(084.3)+502.58.001.18
DOI: 10.21455/gr2021.2-1
Full text
Keywords: geodynamically unstable zones, geological and geophysical parameters, deep structure, Geographical Information Systems, low seismic activity regions
Аnnotation: The results of forecasting geodynamically unstable zones for the territories of Western and Eastern Europe, Ural and Western Siberia are discussed. In these zones the condition, properties and dynamics of the ongoing processes are such that they tend to destabilization under the influence of regional and global tectonic forces, which is manifested in seismicity. The method of identification of the geodynamically unstable zones based on the complex of geological and geophysical data and calculation of the seismic potential was developed on the example of the West Ural region located within the eastern margin of the East European platform, the Pre-Urals foredeep and the Western Ural folde zone. It was applied to the east of the Russian, Pechora, West-Siberian plates and the territory of the United Kingdom of Great Britain and Northern Ireland. The studies were conducted in the Geographic Information System “GEO”. The developed profile method for identifying geodynamically unstable zones made it possible to expand the number of forecast parameters for all considered regions. A unified database has been formed to identify such zones in any low seismic region. Data on geophysical fields were supplemented by analysis of the tectonics of the regions, as well as by deep geophysical exploration. The analysis of the horizontal gradients of the gravitational field, the anomalous magnetic field and the depth of the Moho discontinuity, as well as deep seismic sounding of the earth's crust was carried out. The databases of individual regions were subsequently supplemented with parameters that were not previously used to identify geodynamically unstable zones. The connections of these zones with the deep structure of the regions were determined, which makes it possible to substantiate their existence and clarify their location. The performed studies indicate the possibility of the existence of such zones in any low seismic regions of the world.