The First Results of U-Pb LA-SF-ICP-MS Dating of Detrital Zircons from Middle Riphean(?) Terrigenous Deposits of the Polar Urals

摘要

This paper reports the first results of U-Pb LA-SF-ICP-MS dating of detrital zircons from terrigenous deposits of the Miniseishor Formation, Nyarovei Group of the Kharbei Anticlinorium, the Polar Urals, presumably of Middle Riphean age, located at the Upper Precambrian Polar Ural section base. The data obtained give grounds for constraining the lower age interval of the Miniseishor deposit to the turn of 600 Ma ago. In addition, these data are indicative of the fact that identification of the Nyarovei Group as a Middle Riphean stratigraphic unit is wrong. The whole Nyarovei section was formed in a relatively narrow age interval at the end of the Late Riphean. Erosion products of the adjacent deeply metamorphosed rocks played a key role in the development of deposits throughout this group.