Recent structures and tectonic regimes of the stress–strain state of the Earth’s crust in the northeastern sector of the Russian Arctic region

Resumo

A comprehensive investigation aimed at determining seismotectonic types of destruction and the stress–strain state of the Earth’s crust in the main seismogenerating structures of the Arctic–Asian seismic belt is conducted for the territory of the northeastern sector of the Russian Arctic region. Based on the degree of activity of geodynamical processes, the regional principles for ranking neotectonic structures are elaborated, and neotectonic zoning is carried out based on the substantiated differentiation of the corresponding classes. Within the limits of the Laptev Sea, Kharaulakh, and Lena-Anabar segments, we analyzed I the structural–tectonic position of the most recent structures, II the deep structure parameters, III the parameters of the active fault system, and IV the parameters of the tectonic stress field, as revealed from tectonophysical analysis of Late Cenozoic fault and fold deformations. Based on the seismological data, the mean seismotectonic deformation tensors are calculated to determine, in combination with geological and geophysical data, the orientations of the principal stress axes and to reveal the structural–tectonic regularity for tectonic regimes of the stress–strain state of the Earth’s crust in the Arctic sector of the boundary between the Eurasian and North American lithospheric plates.