OK, Portland and Seattle Wonkers, this is a public service announcement. We are going to need you to find buddies in the comments section (which does not exist), and beg them to let you crash on their couch, because you guys are going to have a REALLY BIG EARTHQUAKE. Yeah, maybe you already knew that, but the rest of America is finding out now, thanks to a fascinating long-read in The New Yorker on what may end up being the biggest natural disaster in U.S. American history. This isn’t some wussy San Andreas Fault 7-point whatever business, this is more along the lines of the 2011 quake in Tōhoku, Japan, which registered 9.0 on the Richter scale and triggered the tsunami that triggered the Fukushima nuclear reactor meltdowns. This is big shit.
You see, it all has to do with something called the Cascadia Subduction Zone, where the Juan de Fuca plate (which is under the ocean) is smooshing itself up under the North American plate (which is on North America), and it has no place to go, because it’s smooshed up against another plate. If you’re into the science of how this happens, go read the article, but here is the gist, involving fun hand exercises:
Take your hands and hold them palms down, middle fingertips touching. Your right hand represents the North American tectonic plate, which bears on its back, among other things, our entire continent, from One World Trade Center to the Space Needle, in Seattle. Your left hand represents an oceanic plate called Juan de Fuca, ninety thousand square miles in size. The place where they meet is the Cascadia subduction zone. Now slide your left hand under your right one. That is what the Juan de Fuca plate is doing: slipping steadily beneath North America. When you try it, your right hand will slide up your left arm, as if you were pushing up your sleeve. That is what North America is not doing. It is stuck, wedged tight against the surface of the other plate.
The North American Plate is Not Doing That, and therein lies the problem. Instead, the edge of the Juan de Fuca plate is pushing against and under it, and the North American Plate is “bulging upward and compressing eastward,” and it will continue to do that until … well, until it doesn’t anymore. At that point it will slam back westward, “like a spring,” and that will be when you all die. WE’RE NOT JOKING, THIS IS SERIOUS. The New Yorker explains that this could happen in two ways, and one of them is very, very bad and will register somewhere between 8.0 and 8.6 on the Richter scale. The other way is worse:
If the entire zone gives way at once, an event that seismologists call a full-margin rupture, the magnitude will be somewhere between 8.7 and 9.2. That’s the very big one.
Okay, convinced yet? Let’s talk about the tsunami this will cause:
When the next very big earthquake hits, the northwest edge of the continent, from California to Canada and the continental shelf to the Cascades, will drop by as much as six feet and rebound thirty to a hundred feet to the west—losing, within minutes, all the elevation and compression it has gained over centuries. Some of that shift will take place beneath the ocean, displacing a colossal quantity of seawater. (Watch what your fingertips do when you flatten your hand.) The water will surge upward into a huge hill, then promptly collapse. One side will rush west, toward Japan. The other side will rush east, in a seven-hundred-mile liquid wall that will reach the Northwest coast, on average, fifteen minutes after the earthquake begins.
Now, the Japanese will have quite a warning for this tsunami, because they will be watching one of their weird game shows where a girl jerks a guy off while he does karaoke, but then there will be a breaking news alert about how there is a tsunami coming, due to the Pacific Northwest just got ruint. The tsunami on this side of the Pacific will start within 10 to 30 minutes:
For the seventy-one thousand people who live in Cascadia’s inundation zone, that will mean evacuating in the narrow window after one disaster ends and before another begins. They will be notified to do so only by the earthquake itself—“a vibrate-alert system,” Kevin Cupples, the city planner for the town of Seaside, Oregon, jokes—and they are urged to leave on foot, since the earthquake will render roads impassable. Depending on location, they will have between ten and thirty minutes to get out.
And what will everything be like after the tsunami is over?
Kenneth Murphy, who directs FEMA’s Region X, the division responsible for Oregon, Washington, Idaho, and Alaska, says, “Our operating assumption is that everything west of Interstate 5 will be toast.”
For the uninitiated, that includes “Seattle, Tacoma, Portland, Eugene, Salem (the capital city of Oregon), Olympia (the capital of Washington), and some seven million people.” But you knew that, if you live in the Northwest, why are you people just sitting there reading this, shouldn’t you be getting boxes and looking into Omaha real estate, ooh it’s nice there this time of year, Omaha.
Because here’s the other kicker: When scientists finally discovered that this damn Cascadia Subduction Zone existed, they were able to figure out approximately how often she blows a gasket, and that number is every 243 years. The last one happened in 1699, long before any of you hipsters discovered Seattle and Portland before it was cool. Well guess what, the Cascadia Subduction Zone was way ahead of YOUR hippie ass, and she’s OVERDUE.
Seriously, please do read the whole article, because the way scientists discovered all this is absolutely fascinating. It involves Japanese history and tree rings and sucking deposits off the ocean floor, cool stuff like that, and it’s Good Science.
And as we said, some of you Seattle and Portlandia (Vancouver too, run for your lives!) people probably are like “duh we know this,” but your governments aren’t doing near enough about it (or maybe it’s just that it’s too little, too late) and your Wonkette is just concerned about you, so come on. You can go stay with Dok in Idaho.