Wait? What?!? I live in the Pacific Northwest. Holy Cow!
The Northwest owes its hazard-prone future to what’s happening underground. Beneath a line of volcanoes that stretches from British Columbia to northern California and includes Mount St. Helens, Mount Rainier and Mount Shasta, one of the Earth’s plates is wedged beneath another.
The fault line is called the Cascadia subduction zone, and it shakes every few hundred years when the plates shift. The quaking, which can last for minutes, triggers a tsunami that follows 10 to 20 minutes later and reaches heights of up to 15 feet.
Records show that 20 earthquake-generated tsunamis have struck the Northwest in the last 10,000 years — an average of one tsunami every 500 years. The last one happened nearly 310 years ago, on January 26, 1700.