GPS bolsters view that big Cascadia quakes could hit inland

Major earthquakes occurring along the Cascadia subduction zone off the coast of Washington state could strike closer to the state’s urban areas than some models have suggested, a new study notes.

GPS data gathered at dozens of sites throughout western Washington hint that slippage along the interface between the North American and Juan de Fuca tectonic plates could occur as deep as 25 kilometers below the Earth’s surface, says Timothy I.