Metasandstones of the Vilenga Formation of the Vetrenyi Belt: Composition, Isotopic-Geochronological Characteristic, and Provenances

Two primary and two subordinate age groups of detrital zircons are distinguished as a result of isotopic-geochronological studies of metasandstones of the Vilenga Formation of the Vetrenyi Belt. A zircon group with an age of 2751 +/- 7 Ma was potentially sourced from late granitoids (granodiorite-granite-leucogranites) abundant in the northern part of the Vodlozero domain. No source with an age of 2823 +/- 5 Ma has been identified in the adjacent part of the Karelian granite-greenschist area. The zircons with the age of 2874 Ma were sourced from rocks of the BADR (basalt-andesite-dacite-rhyolite) series and adakites of the Sumozero-Kenozero greenschist belt. Previous study of detrital zircon from basal horizons of sections of the Vetrenyi Belt (Toksha Formation), as well as the underlying rocks for the metasandstones (Kozhozero Formation), showed the same main age peaks, which may indicate a stable tectonic setting at the beginning of the Paleoproterozoic and a common provenance of clastic material. Intermediate-felsic rocks with an age of 2940 Ma could also have made a small contribution in the formation of metasandstones.