The Timan-North Urals region: deep structure, substantive-structural evolution, age boundaries

The present state of geological study of a large subarctic region including the north of the Urals, Pai-Khoi, Kanin-Timan Ridge and the Pechora Syneclise is shown. New isotope-geochronological data on metamorphogenic zircons are given, which unambiguously indicate that the Lower-Precambrian complexes are present within the Timan-North Urals region. The results of 3D modeling confirm the idea that they are fragments of the crystalline basement of the East-European platform, in- volved in the structures of the Timanides and the northern part of the Uralides. It is established that the lower age boundary of the Upper Precambrian formations of the Timan-North Urals region is close to the boundary of the Middle and Late Ri- phean and, most likely, does not go beyond the Late Riphean, and the time of for- mation of the collisional orogen Timanides is limited to the Vendian, possibly to the very beginning of the Cambrian. The beginning of the formation of basal deposits of the Paleozoic, testing the processes of large-scale continental riphogenesis, which subsequently have led to the spreading and opening of the Paleo-Ural Ocean, refers to the Cambrian and Ordovician boundary, and the ophiolites, as fragments of the oceanic crust, were formed in the Ordovician.