О выделении на Урале палеозойских фаций континентального подножия

The allocation of the Urals Paleozoic continentalfoot facies

The Central Ural megazone composes the axial part of the Ural Mountains, where it forms a number of large megaanticlinoria. In the Southern Urals, it is established that the Central Ural megazone is composed of 4 different formation geodynamic complexes:Riphean, almost non metamorphosed sedimentary shallow water terrigenous carbonate complexes of the East European platform cover.Archean Paleoproterozoic polymetamorphic complexes representing marginal parts of the East European platform basement.morphism of the greemorphism of the greeschistschistacies. Tacies. Te Pa eozoice Pa eozoicTerrigenous deposits (aleuroschists, quartzite sandstones with subordinate interbeds of conglomerates, etc.) of great thickness, folded and meta morphosed in the greenschist facies. Among these strata, the Early Middle Paleozoic sedimentary complexes of the continental foot (Suvanyak complex and its analogues) are distinguished, which are comparable in all respects to modern analogues, but have undergone intense folding and metan f h lage of the Suvanyak complex is proved by the author's find of the Early Ordovician conodonts Oistodus aff. contractus Lind., Oistodus sp . Thus, for the first time in the Urals, we distinguished the Paleozoic schist-terrigenous facies of the continental foot (the Suvanyak complex and its analogues), which differ from the deposits of the continental slope adjacent to the west, in the first place by much greater thicknesses, since the siliceous sedimentation here is replaced by the terrigenous one. A very small share of coarse frag mental sediments in the Suvanyak complex most likely indicates a flat relief of the eroded eastern part of the East European platform. The present day width of the Suvanyak complex (20 km), taking into account the intense folding actually observed here, should be increased to 55 60 km. But the modern analogues, as a rule, are 3 4 times wider. It follows that the Suvanyak complex is only a surviving fragment of the initial sedimen tary prism of sediments of the continental foot, its marginal western part. And the eastern one, apparently most of the sediments of this type, were absorbed by the subduction paleozone, i.e. by the MUF (Main Ural Fault).