Lithospheric structure along the Queen Charlotte margin in western Canada: Constraints from flexural modeling

The Queen Charlotte fault zone along the western margin of Canada, a right-lateral transform, is part of the boundary between the Pacific and North America plates. Combining reflection and refraction surveys and flexural modeling, we place limits on the amount of underthrusting of the Pacific plate beneath the North America plate. Results from our two-dimensional elastic modeling suggest 10-15 km of underthrusting along the northern Queen Charlotte Islands, in agreement with the amount of underthrusting inferred from plate motion models.