Ore-Bearing Quartz-Light-Colored Mica Metasomatic Rocks in the Regional Precambrian Unconformity Zones in the Eastern Aldan Shield

This article summarizes research results obtained for Late Proterozoic (1.32-1.15 Ga) ore-bearing (U, Mo, V, Zn, and Ag) quartz-light-colored mica metasomatic rocks of the Uchur-Ulkan region in the eastern Aldan Shield. Large faults and zones with structural and stratigraphic unconformities govern the development of mineralization. The study of the mineral composition of metasomatic rocks resulted in identification of sericite, hydrosericite, and roscoelite metasomatic rocks with quartz. Wallrock metasomatic features were described in gneisses, marbles, and volcanosedimentary rocks, and metasomatic zoning was revealed in rocks of different types. The overprinted metamorphic processes could be related to Late Proterozoic rejuvenation processes and extraction of ore components from rocks of the Ulkan Complex (1.72-1.68 Ga) at the metamorphic basement of the Siberian Platform and its platform cover. It is concluded that structural settings, age, and a number of composition characteristics, uranium ore deposits in the eastern Aldan Shield are similar to the Canadian and Onega "unconformity-type" deposits.