New data on detrital zircons from the sandstones of the lower Cambrian Brusov Formation (White Sea region, East-European Craton): unravelling the timing of the onset of the Arctida-Baltica collision

摘要

The basement of the northeastern periphery of the East-European Craton (EEC) is composed of volcanic-sedimentary sequences, volcanic rocks, granitoids, and rare ophiolite complexes. Geochronological data constrain their age from ca. 750 to 500Ma, and there is a consensus that these rocks represent relicts of a late Neoproterozoic-Cambrian Pre-Uralides-Timanides orogeny. Combining new integrated isotopic (U-Pb, Lu-Hf) and trace-element data (TerraneChrone((R)) approach) on detrital zircons from sandstones of the lower Cambrian Brusov Formation in the Mezen basin (White Sea region in the northeastern periphery of the EEC) with available studies on detrital zircons from Neoproterozoic-middle Cambrian (meta)sedimentary units of the northeastern periphery of the EEC allow us to conclude that (1) the onset of the Arctida-Baltica collision can now be constrained to the time interval between ca. 540 and 510Ma and (2) the Ediacaran-early Cambrian Mezen sedimentary basin was a basin on the Timanian passive margin of Baltica up to 540Ma, but was not a foreland basin of the Pre-Uralides-Timanides orogen.