Episodic Volcanism in the Buck Creek Complex (Central British Columbia, Canada): A History of Magmatism and Mantle Evolution from the Jurassic to the Early Tertiary

摘要: The Buck Creek volcanic complex of the Intermontane Superterrane Canadian Cordillera records a long history activity from Cretaceous through to Eocene, when magmatic peaked, Miocene. Its basement includes primitive continental arc rocks Jurassic Hazelton Group (∼200 Ma; mainly basalt and andesites) emplaced prior accretion Stikinia during Mesozoic. In contrast, in post-accretionary complex, major pulse volcanism started with extrusion margin calc-alkaline (basaltic andesites rhyolites) Tip Top Hill Formation (∼85 Ma). Their Nd-Sr isotopic compositions resemble those pre-accretionary Group. However, this was more evolved its crust significantly thicker than Hazelton. Mafic both suites were generated spinel-bearing mantle source. Eocene volcanics (∼50 Ma) evolve...