The Cascadia convergent margin, which flanks the western side of Oregon, Washington and Vancouver Island, marks the subduction boundary between North America and the Juan de Fuca plate. The forearc region is underlain by lower Eocene basalt except in Olympic Peninsula section where uplift has tilted the basalt into a sleep east-plunging anticline and has exposed the underlying Olympic subduction complex. This research will continue a project aimed at understanding this anomalous uplift and its causes. Results are important to the timing and geometry of the Olympic subduction complex and has application to understanding other ancient subduction complexes.
