Age and provenance of the Precambrian Middle Timan clastic succession: Constraints from detrital zircon and rutile studies

Abstract

The Precambrian sedimentary succession of Middle Timan provides important information on the coeval history of Baltica prior to assembly of the Rodinia supercontinent. This study comprises a comprehensive integrated provenance study based on samples collected from Precambrian clastic rocks of the Chetlassky Kamen and Volsko-Vymskaya Ridge. The maximum depositional age of the studied succession is constrained as latest Mesoproterozoic – earliest Neoproterozoic based on the youngest detrital zircon and rutile ages. Metasandstone samples within the succession are arkose, sublitharenite and litharenite. The distributions of detrital zircon U-Pb ages from the studied metasedimentary rocks are very comparable, yielding approximately 50% Mesoproterozoic ages within the ranges 1470 – 1550 and 1170 – 1370 Ma, 45% Paleoproterozoic ages and 5% Archean ages, with predominant populations grouping at 2500–2700 and 1800–1900 Ma. Comparable detrital zircon age distributions within the coeval strata of northern Baltica suggest a common provenance area. Analysis of detrital rutile suggests the widespread distribution of latest Mesoproterozoic – earliest Neoproterozoic metamorphism within the provenance area. A comparison of detrital zircon age distributions from the coeval strata of Baltica and Laurentia also revealed a striking similarity. Therefore, we suggest that clasts were in fact predominantly sourced from the Grenvillian-Sveconorwegian Orogen, with possible reworking of older zircon grains from older sedimentary rocks involved in the deformation and uplift. Our data support the tectonic model invoking a continuation of the Grenvillian-Sveconorwegian Orogen further to the east across the Barents Sea from its closest modern outcrop in Scandinavia.