The Ordovician Thores volcanic island arc of the Pearya Terrane from northern Ellesmere Island formed on Precambrian continental crust

Ion microprobe UPb zircon dating of intermediate to felsic rocks coupled with bulk-rock geochemistry analyses and compared previously published data shows that the Thores Suite Pearya Terrane northern Ellesmere Island (Arctic Canada) represents an Early Ordovician (c. 490–470 Ma) suite formed in island arc setting. Interestingly, three out five dated samples contain abundant xenocrystic have ages spanning from c. 2690 Ma 520 Ma. The vast majority are Precambrian age typical Laurentia. youngest well-pronounced cluster around 580–570 is inferred be expression Timanide Orogen, traditionally ascribed Baltica. This geochronological dataset provides new insight on origin Terrane, which was thought due M'Clintock orogenic event commonly treated as independent Caledonian tectonism. We suggest a sliver continental crust within Iapetus Ocean. timing igneous activity recorded by consistent other arcs subduction-related metamorphic units occur Caledonides Scandinavia Svalbard. Hence, we volcanic closely associated equivalent developed Its juxtaposition successions explained large-scale, left lateral, strike-slip system operating along northeastern margins Baltica Laurentia, coeval main collision between two continents. responsible for multiple terranes contrasting histories can traced present day High Arctic, e.g. southwest Svalbard Terrane.