U-Pb (LA-ICP-MS) dating of detrital zircons from clastic sediments composing lowest part of Precambrian sequence of Northern Timan

Abstract

The article presents the first U-Pb data on the age of detrital zircons from clastic sediments of Rumyanichnaya Formation included in Barma Group which constitutes the lowest outcropped part of the Precambrian sequence of the Northern Timan. Age data (LA-ICP-MS) for 94 zircon grains from fine-grained aleuritic sandstone cover the range of 981–2582 Ma. Weighted average age of the two youngest zircons yields the age of 983±40 Ma which provides grounds to assume that sediment deposition took place in Late Riphean (Neoproterozoic). The accumulation of clastic sediments that compose the all three formations of Barma Group (~5 km thick) was controlled mostly with terrigenous material from eroded rock complexes coeval with crystalline complexes of Fennoscandia and Central Russian Belt.