Geology of National Parks, 3D and Photographic Tours
View of the ferry dock at Edmonds, WA (west side of Puget Sound) with the high peaks of the eastern Olympic Mountains in the distance. The high peaks are part of the Olympic Peninsula, much of which is within Olympic National Park.
The core of the Olympics is composed of relatively young oceanic rocks (Eocene to Miocene) that have been accreted onto the western coast of Washington. This region is a plate boundary where oceanic crust has been subducted beneath the North American tectonic plate. During this process, some strata are scraped off the oceanic plate and added to the margin. The rocks in the Olympics have experienced a range of metamorphic alteration, folding, and faulting during their migration from the ocean floor to the high peaks region now exposed in the Olympia Highlands of northwestern Washington (Harris and others, 1997; Rau, 1987; Tabor, 1987).