Major and trace element compositions and Sr-Nd-Pb systematics of crystalline rocks from the Dawson Range, Yukon, Canada

Geochemical (major, trace, and rare earth elements) and isotopic (Nd, Sr, a nd Pb) data of the Devono-Mississippian Wolverine Creek Metamorphic Suite, mid-Cretaceous Dawson Range batholith, mid-Cretaceous Casino Plutonic Suite , and Late Cretaceous plutons provide new information on the origin and evo lution of the rocks from the Dawson Range in west-central Yukon, northern C anadian Cordillera. Isotopic and other geochemical data for the Wolverine C reek Metamorphic Suite metasedimentary rocks indicate that the detrital com ponents were derived from two distinct provenances: (1) the North America c raton, which contributed evolved felsic, upper crustal material; and (2) a calc-alkaline arc, which shed juvenile mafic-intermediate material. The geo chemical affinity of the metaigneous rocks indicates that the Yukon-Tanana terrane represented a continental arc during Devonian-Mississippian times, with magmas derived from geochemically primitive sources and partial meltin g of the Yukon-Tanana terrane supracrustal rocks. The Dawson Range batholit h likely represents crustally derived magmas from the Yukon-Tanana terrane during the mid-Cretaceous, with the contemporaneous Casino Plutonic Suite r epresenting a late-stage fractionate of these magmas. The Late Cretaceous p orphyry Cu mineralization is genetically related to plutons derived from ma ntle-source magmas related to active subduction.