9804961 Kodama The Cordillera of western North America is composed of an amalgamation of tectonic terranes, attached at various times onto the stable North American craton, after being transported variable distances from their origins. This transport and amalgamation history is not well known and has given rise to several conflicting ideas. These proposals address two important but conflicting and mutually exclusive hypotheses, namely whether the Insular superterrane, presently in western British Columbia, originated in the Cretaceous north of California (no or small northward movement) or from far to the south, near Baja California. The work will be a careful reassessment of prior data and the assumptions underlying those data. Results are expected to help resolve the important controversy about the origins of the Insular terrane.