The western margin of North America is an active subduction zone except for the zone along the Cascade Range, which is a transform fault boundary.

Question

Quizplus · Accepted Answer

The statement is incorrect. The zone along the Cascade Range is actually a convergent plate boundary where the oceanic Juan de Fuca Plate is being subducted beneath the North American Plate, similar to the rest of the western margin of North America. The transform fault boundary is located further north, where the Juan de Fuca Plate and the Pacific Plate are sliding past each other along the Queen Charlotte Fault.

The Western Margin of North America Is an Active Subduction