■ Abstract The Cordilleran orogen of western North America is a segment of the Circum-Pacific orogenic belt where subduction of oceanic lithosphere has been underway along a great circle of the globe since breakup of the supercontinent Pangea began in Triassic time. Early stages of Cordilleran evolution involved Neoproterozoic rifting of the supercontinent Rodinia to trigger miogeoclinal sedime...

1) An accretionary prism with a constant width of approximately 75 km does exist; 2) The morphology of this prism varies rapidly along the arc and is linked, firstly to the morphology and structure of the upper part of the dipping plate and, secondly to the presence of volcanic island acting as sediment sources; The island arc and its connecting structural features such as troughs at the rear o...

Wrangellia consists largely of an oceanic plateau, a vast outpouring of basalt and more Mg-rich magma that erupted onto the ocean floor and was subsequently accreted to the western margin of the North American plate. Flood basalts form extensive sequences on Vancouver Island and are believed to have formed by melting in a mantle plume (an upwelling zone of hot mantle rock). They form the oceani...

Plate reconstructions of the Panthalassa Ocean typically portray a simple system diverging plates surrounded by active margins, yet geological and seismic tomographic records demonstrate that intra-oceanic subduction existed. Here, we reconstruct plate tectonic evolution pre-Cretaceous Oku-Niikappu island arc, remnants which are exposed on Hokkaido, Japan. This arc formed at Jurassic zone separ...

Continental arcs have an episodic magmatic activity over long-time periods, which is believed to modulate long-term climate. Island also the potential release large amount of CO 2 into atmosphere, but whether they display history throughout their lifespan that contributes (>10 Ma) climate changes remains open question. To set additional constraints on island arcs, here we examine fresh b...