Some Estimates of the Stress–Strain State of the Earth’s Crust of the Russian Platform

Based on literature data and original constructions of the focal mechanisms of earthquakes within the Romashkinskaya seismically active zone of the Tatar Arch for 1992–1995, additional information was obtained on the nature of the stress–strain state in the central Russian Platform, which is a “white spot” on the well-known world stress maps (WSM). Predominant subhorizontal uniaxial compression in the southeast–northwest direction is established, which is agrees well with the observed regional maximum horizontal stress field SHmax in Western Europe. As one of the possible reasons for this orientation of this compression, along with a plate tectonics interpretation, a system of planetary tectonic fracturing of rock material is proposed. This fracturing, in light of the ideas obtained here on the nature of the stress–strain state of the crust, can be understood as numerous planes of thrust and shear dislocations that formed during deformation of crustal material under horizontal compression in the indicated direction.