Guest Contributor John Rolls
The Giant, Underestimated Earthquake Threat to North America
The enormous fault off the coast of the Pacific Northwest has been silent for three centuries. But after years of detective work, geologists have discovered that it can unleash mayhem on an epic scale.
Now scientists are calling attention to a dangerous area on the opposite side of the Ring of Fire, the Cascadia Subduction Zone, a fault that runs parallel to the Pacific coast of North America, from northern California to Vancouver Island.
This tectonic time bomb is alarmingly similar to Tohoku, capable of generating a megathrust earthquake at or above magnitude 9, and about as close to Portland, Seattle, and Vancouver as the Tohoku fault is to Japan’s coast.
Decades of geological sleuthing recently established that although it appears quiet, this fault has ripped open again and again, sending vast earthquakes throughout the Pacific Northwest and tsunamis that reach across the Pacific.
What happened in Japan will probably happen in North America. The big question is when.
Experts say an event of this kind occurs roughly every 400-600 years, and the area is now overdue for a similar quake that could leave thousands dead or displaced.
Worst-case scenarios show that more than 1,000 bridges in Oregon and Washington state could either collapse or be so damaged that they are unusable.
The main coastal highway, US Route 101, will suffer heavy damage from the shaking and from the tsunami.
Traffic on Interstate 5 — one of the most important thoroughfares in the nation — will likely have to be rerouted because of large cracks in the pavement.
Seattle, Portland and other urban areas could suffer considerable damage, such as the collapse of structures built before codes were updated to take into account a mega-quake.
The last time the region faced a ‘Big One’ was in 1906 when San Andres unleashed an earthquake that killed roughly 3,000 people.
This summer’s drill, dubbed Cascadia Rising, will test to see how local and state emergency responders, Fema, and a number of military groups work together.
At the U.S. Geological Survey (USGS) lab in Menlo Park, seismometers peg the quake at magnitude 8.1, and the tsunami detection centers in Alaska and Hawaii begin waking up the alarm system with standby alerts all around the Pacific Rim.
Early morning commuters emerging from a BART station in San Francisco feel the ground sway beneath their feet and immediately hit the sidewalk in a variety of awkward crouches, a familiar fear chilling their guts.
Then another little rough spot on the bottom of the continent snaps off.
The chances of a 9.0 earthquake slamming the Pacific Northwest are disturbingly high. Introducing a novel way to engage the threat: reported science fiction.
There is a 22 percent chance that by the time you finish reading this sentence, there will have been an earthquake somewhere on earth.
This is a probability that is hard to grasp—it seems both obvious and diffuse. The world is a big place, and most earthquakes are relatively small.
But consider this: Geologists put the chance of a full rupture of the Cascadian Subduction Zone—that’s the fault line off the coast of California, Oregon, Washington, and British Columbia—at 7-15 percent over the next years.1 This would result in a 8.7 to 9.3 Mw earthquake. The biggest quake in recorded history, the 1960 Valdivia quake in Chile, weighed in at 9.5 Mw; and the recent 2011 Tōhoku earthquake off the coast of Japan measured at 9.0 Mw. Relatively speaking, there is a significant chance the Pacific Northwest region will see an earthquake of historical magnitude in the not-so-distant future.
EXTREME DANGER of another, even larger earthquake than the massive 7.1 which struck south of Mexico City earlier this week.
Roads in the area have begun OUT-GASSING . . . they appear to be Breathing . . . meaning the earth below is being squeezed so hard, it is venting gas from deep in the earth. This is a major warning sign of a pending, Extremely Large earthquake!
I cannot over-state the danger of what we see taking place in the video above. The fact that this road is moving up and down, and hissing as underground gas comes out, is an absolute warning sign that another Extremely Large earthquake is pending in that region.
What’s taking place to cause this gassing is that the earth is being squeezed with so much pressure, gas is venting out of the surface. All that squeezing means something very big is building underground.
Because Portland has been my hometown for nearly nine years, I went looking for answers about this chance event, if and when it were to happen here. I found thousands of pages worth of studies and reports, written by hundreds of public employees who’ve long been working on this very question.
The Federal Emergency Management Agency, the Oregon State Office of Geology and Mineral Industries, the Oregon Department of Transportation, the Oregon Office of Emergency Management, the Portland Bureau of Emergency Management, the city Bureau of Transportation and even the Parks Department—all of these agencies and more have taken a crack at telling parts of the story about what might happen during a Cascadia Subduction Zone event.
The accounts, informed by geologists, seismologists, geographers, engineers, transit experts, and city officials, are detailed, compelling, and often exhaustive.
Some of it is quite alarming. One study declared the possibility that of 2,671 bridges in the “strong” shaking zone, 399 would be at least partially destroyed, and 621 heavily damaged.4 That means 38 percent of the region’s bridges, out of service, all at once.
There are systemic vulnerabilities affecting Oregon as well. Nearly all the petroleum products for the entire state are imported through one particular area of Northwest Portland.5 Despite being a modern state, Oregon is still cut off from the rest of the country by its terrain, and connected by only a limited number of roads, railroads, and sea lanes.
I read hundreds, if not thousands of other facts, possibilities, probabilities, and potentialities like this, which remind me how amazing it is that our society holds together even in the best of times.
But these reports, too, are strictly in the language of estimates, in scenarios, in potential plans. And naturally so; there are no guarantees in engineering, let alone in emergencies.
It is impossible for anyone to say exactly which bridges will collapse, which roads will be blocked, and which buildings will have electricity and sewer service.
Similarly, there is no way to predict exactly how many people will die: either immediately, or in the long and difficult rebuilding process when water and electricity may be scarce. But there are estimates. There are scenarios.
I took to telling myself, if it’s going to happen, it’s going to happen. But fate is a solipsistic wall erected between oneself and the world—a world which is always comprised of confounding, frustrating, and mysterious facts.
With a time line of 41 events the science team at OSU has now calculated that the California–Oregon end of Cascadia’s fault has a 37 percent chance of producing a major earthquake in the next years. The odds are 10 percent that an even larger quake will strike the upper end, in a full-margin rupture.
Given that the last big quake was 312 years ago, one might argue that a very bad day on the Cascadia Subduction Zone is ominously overdue. It appears that three centuries of silence along the fault has been entirely misleading. The monster is only sleeping.
Being prepared always is a perfect move towards living an enjoyable life.
You need to prepare for both success and failure simultaneously.
Being alert could save the lifestyle of your friends, relatively and more importantly your valuable life.
Bad things that are anticipated to occur need to be prepared for perfectly because they are inescapable, such as global warming.