Seismotectonic Analysis and Development of the Mathematical Model of the Stress-Strain State of the Earth’s Crust in the Zone of Collision of the Western Tien Shan with the Pamir Arc

Abstract

The seismotectonics of the Western Tien Shan is determined by collisional processes in the zone of interaction between the Southern Tien Shan and the Pamir arc. This process contributes to maintaining the high seismic potential of the region, as evidenced by the destructive earthquakes that have taken place here from ancient times to the present and their traces - seismic dislocations. Strong earthquakes are genetically associated with areas of intense movements in recent and modern times, with zones of active faults. An improved map of the active faults of the Western Tien Shan has been constructed and, on its basis, a mathematical model of the stress-strain state has been constructed using the Stokes equations. At the same time, the dynamic influence zones of the South Fergana and North Fergana faults are additionally included in the model. At the same time, a significant correction was obtained in the distribution of stresses in the earth’s crust of the region. The velocity fields of modern movements of the Western Tien Shan corresponding to GPS data are analyzed. The displacement velocity vectors are grouped in the direction into several zones. The nodes of intersection or articulation of movements of different directions are assigned to the most tectonically stressed areas. The most active seismic zones are identified on the basis of these nodes and the resulting stresses. They are compared to similar areas with a high concentration of strong earthquakes.