Cascadia Subduction Zone One of Earth’s Top Hazards, Comes into Sharper Focus
Off the coasts of southern British Columbia, Washington, Oregon, and northern California lies a 600-mile-long strip where the Pacific Ocean floor is slowly diving eastward under North America. This area, called the Cascadia Subduction Zone, hosts a megathrust fault, a place where tectonic plates move against each other in a highly dangerous way.
The plates can periodically lock up and build stress over wide areas eventually to be released when they finally lurch against each other. The result: the world's greatest earthquakes, shaking both seabed and land, and generating tsunamis 100 feet high or more.
Such a fault off Japan caused the 2011 Fukushima nuclear disaster. Similar zones exist off Alaska, Chile, and New Zealand, among other places. At Cascadia, big quakes are believed to c...
