Abstract:
In the crustal history of the northeast of the European part of the USSR (including the northern Urals), the tectonic processes of the pre-Baikalian, Baikalian, Caledonian, Hercynian and Alpine stages were the most important. The geologic concepts of the polycyclic development of the Earth's crust and the more-or-less persistent synchronous events in its major structural elements have been confirmed. The most numerous age values obtained for one zone or another correspond to the last process that disturbed the K-Ar equilibrium in the systems studied, and pertain to the periods of consolidation of the major areas of the Earth's crust within specific geostructures. The culminations of the tectonomagmatic processes identified reflect global processes that caused radical transformations of the physical geographic conditions and ecological situation over the whole Earth.