The Cascadia fault line just became as popular as the San Andreas fault line thanks to a New Yorker earthquake article, which discussed 2015 earthquake predictions in addition to the possibility of a devastating tsunami wiping out the coastline of California, Oregon, and Washington state. But is the Cascadia subduction zone really capable of producing a megaquake?
In a related report by the Inquisitr, some scientists actually believe an oarfish sighting can be used for earthquake predictions since they may give a hint about the geological processes occurring deep under the ocean.
The New Yorker article does not begin by describing the “really big one” in detail. At first, they detail why exactly the San Andreas fault line is over-hyped in comparison to the Cascadia fault line.
“Every fault line has an upper limit to its potency, determined by its length and width, and by how far it can slip. For the San Andreas, one of the most extensively studied and best understood fault lines in the world, that upper limit is roughly an 8.2—a powerful earthquake, but, because the Richter scale is logarithmic, only six per cent as strong as the 2011 event in Japan.”
The Cascadia subduction zone, on the other hand, has a greater potential for devastation. It runs from Cape Mendocino, California, all the way up to Vancouver Island, Canada. It is noted that the Cascadia fault line is slowly being compressed over time at a rate of 30 to 40 millimeters a year. While the earth is relatively elastic, their earthquake prediction claims a megaquake may be possible once this elasticity reaches its limit.
“Sooner or later, North America will rebound like a spring. If, on that occasion, only the southern part of the Cascadia subduction zone gives way—your first two fingers, say—the magnitude of the resulting quake will be somewhere between 8.0 and 8.6. That‘s the big one. 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.”
Well, at least we now know the next movie sequel Dwayne “The Rock” Johnson will be starring in.
Joking aside, the worst part about the earthquake prediction is the tsunami. If the Cascadia fault line ruptures as described, the shifting of the tectonic plate would displace a monstrous amount of seawater, which would in turn send a giant wave hurtling at the coasts of California, Oregon, and Washington State.
While this description by the New Yorker sounds scary, some may wonder if scientists are really making earthquake predictions which make out the Cascadia subduction zone to be a killer. Ian Madin, a geologist and chief scientist at Oregon Department of Geology and Mineral Industries, believes the Cascadia fault line could in fact cause a megaquake.
“As the two plates collide,” Madin says, “the fault gets stuck, eventually slipping when enough stress builds up to produce a great earthquake…. On top of that, we have a lot of mountainous terrain that is highly susceptible to landslides, large areas that are susceptible to liquefaction, and 300 miles of coast that will be inundated by tsunamis that will arrive within 15 to 20 minutes of the earthquake and may locally reach elevations of 100 feet above sea level.”
According to FOX4KC, a megaquake prediction by Dr. Chris Goldfinger, a marine geologist and professor at Oregon State University, claims the Cascadia fault line suffers an earthquake once every 250 years. This is dangerous because he says, “We’re 300 years into a 240 year cycle.” Goldfinger claims the southern region around California and Oregon has a 35 to 40 percent probability of having a megaquake in the next 50 years, while the northern region around Washington state and Canada only has a 10 to 15 percent probability of occurring.
Just how devastating would this megaquake be? The Oregon Resilience Plan claims a megaquake along the west coast could cause $30 billion in damage within Oregon alone. Kenneth Murphy, who directs FEMA in the areas which would be affected by the quake, says that this megaquake could kill around 13,000 people. Another 27,000 would be injured, and millions would be displaced from their damaged and destroyed homes.
“Our operating assumption is that everything west of Interstate 5 will be toast,” Murphy said. “This is one time that I’m hoping all the science is wrong, and it won’t happen for another thousand years.”
Kevin Cupples, the city planner for the town of Seaside, Oregon, notes that if the earthquake predictions about the Cascadia fault line are correct then tourists and the elderly will be in deep trouble.
“We can’t save them,” Cupples says. “I’m not going to sugarcoat it and say, ‘Oh, yeah, we’ll go around and check on the elderly.’ No. We won’t.”
These dire earthquake predictions may be alarming, but it should be noted that earthquake predictions are notoriously unreliable. Robert J. Geller, professor of earth and planetary science at the University of Tokyo’s Graduate School of Science, once wrote that making an earthquake prediction “seems to be the alchemy of our times.”
At the same time, scientists are warning the public about the Cascadia fault line since it truly is possible for a megaquake to occur. The goal is for the public to have an awareness of when there is a heightened risk, but without spreading unnecessary fear or panic over potentially unpredictable earthquakes. In the mean time, Hollywood is certain to capitalize on the hype by making a Cascadia movie.
[Image via IT Pro Portal]