The principal objective of this research project is to document magmatic evolution within an exposed crustal section of a Jurassic island-arc complex that was accreted to the North American continent. Rock units representative of the lower, middle and upper crustal levels of the Bonanza arc of Vancouver Island and others representative of preexisting crust into which the magmatic rocks were emplaced will be studied by detailed field work, geochemical analysis, and geochemical modelling. The study should elucidate the internal structure of the arc and the chemical evolution of arc magmas as they pass through and interact with the surrounding crust.