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

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.

U-Pb (LA-ICP-MS) dating of detrital zircons from clastic sediments of upper part of Precambrian basement of Northern Timan

The article presents the first U–Pb data on the age of detrital zircons from clastic sediments of Yambozero Formation (Barmin Group) which constitutes the upper part of the Precambrian sequence of the Northern Timan. Age data for 80 zircon grains (LA-ICP-MS) cover the range of 989–2713 Ma. Weighted average age of the three youngest zircons yields the age of 1004±15 Ma which provides grounds to assume that sediment deposition took place in late Riphean (Neoproterozoic). The accumulation of clastic sediments of Yambozero Formation was controlled mostly with terrigenous material from eroded rock complexes coeval with crystalline complexes of Fennoscandia and Central Russian Belt.

Age of lower Paleozoic rocks composing erosional outliers on Manpupuner Ridge (Northern Urals)

The article presents the first U-Pb data on the age of the rocks composing scenic erosional outliers located on the Manpupuner Ridge in the Northern Urals. Based on the analysis of the ages of detrital zircons micaceous quartzites exposed on the Manpupuner Ridge are thought to belong to Lower Ordovician Telpos Formation. Sources of clastic material are supposed.