Saturday, July 27, 2019

The Coming Earhquakes:

What Do NASA And The US Government Know That We Dont Know?

According to the director of the Southern California Earthquake Center, Thomas Jordan, "the San Andreas fault appears to be in a critical state and as such, could generate a large earthquake imminently". Describing the situation at the southern end of the fault as "locked, loaded and ready to go", as Strange Sounds reported in this July 21st storythere has not been a major release of stresses in the southern portion of the San Andreas fault system since 1857 so the stress between the Pacific plate and the North American plate have kept building up since then, over 150 years worth of energy.
And while the Strange Sounds story reports that we've had periodic big quakes along the San Andreas that have been both catastrophic and have helped to alleviate some of the energy along the fault line that's been building up, experts are warning it's just a matter of time before the energy accumulated over the past 150+ years explodes in a catastrophic megaquake. 
In 1906, some of these stresses were catastrophically released in the San Francisco Bay area in a 7.8 magnitude event and again, in northern California, during the 6.9 magnitude 1989 Loma Prieta earthquake. Events of these magnitudes, however, have not occurred along the San Andreas fault in the south of the state – the 1994 Northridge event was associated with a nearby, but separate, fault system – leading to the suggestion that one is imminent and, given the amount of stress that might actually have accumulated, when it arrives it will be the “Big One”.

Yet as we'll also explore within the next section of this story below, the 'big one' hitting the San Andreas isn't even the biggest earthquake threat now facing the United States, with the Cascadia Subduction Zone potentially set to pop off a quake that might make the 'big one' along the San Andreas fault look like a leisurely walk in the park. 

As the New Yorker had reported as their subtitle of this July of 2015 story titled "The REALLY Big One", "one day, a gigantic earthquake will destroy a sizeable portion of the Pacific Northwest, it's just a matter of time." The first sentence that went with the lead photo seen above of their story: "The next full-margin rupture of the Cascadia subduction zone will spell the worst natural disaster in the history of the continent.

As Strange Sounds had reported in this January 29th story titled "The MEGA Cascadia earthquake is OVERDUE and could strike the west coast of the US at any moment – creating huge 30 metre-high tsunami waves within seconds – Prepare for this apocalyptic event", according to geologist Yumei Wang of the Oregon Geology and Mineral Industries, the major earthquake in the Cascadia region is already more than 50 years overdue. Will we witness it in our lifetime? 

The following excerpts come to us from this New Yorker story saved at Archive, a story that all of the geophysicists, volcanologists and seismologists that Steve Quayle and his production crew are interviewing for a new project he is working on consider the finest journalistic article written to date on the true dangers of Cascadia.

Most people in the United States know just one fault line by name: the San Andreas, which runs nearly the length of California and is perpetually rumored to be on the verge of unleashing “the big one.” That rumor is misleading, no matter what the San Andreas ever does. 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.

Just north of the San Andreas, however, lies another fault line. Known as the Cascadia subduction zone, it runs for seven hundred miles off the coast of the Pacific Northwest, beginning near Cape Mendocino, California, continuing along Oregon and Washington, and terminating around Vancouver Island, Canada. The “Cascadia” part of its name comes from the Cascade Range, a chain of volcanic mountains that follow the same course a hundred or so miles inland. The “subduction zone” part refers to a region of the planet where one tectonic plate is sliding underneath (subducting) another. Tectonic plates are those slabs of mantle and crust that, in their epochs-long drift, rearrange the earth’s continents and oceans. Most of the time, their movement is slow, harmless, and all but undetectable. Occasionally, at the borders where they meet, it is not.

Their story then gave us a little 'hand game' that we can try along at home that helps illustrate what the Cascadia Subduction Zone is facing before dropping the bomb on us; such a quake when finally released could be between an 8.0 magnitude quake and an 8.6, "and if the entire zone gives way at once, the magnitude will be somewhere between 8.7 and 9.2"

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.

Without moving your hands, curl your right knuckles up, so that they point toward the ceiling. Under pressure from Juan de Fuca, the stuck edge of North America is bulging upward and compressing eastward, at the rate of, respectively, three to four millimetres and thirty to forty millimetres a year. It can do so for quite some time, because, as continent stuff goes, it is young, made of rock that is still relatively elastic. (Rocks, like us, get stiffer as they age.) But it cannot do so indefinitely. There is a backstop—the craton, that ancient unbudgeable mass at the center of the continent—and, 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.

Flick your right fingers outward, forcefully, so that your hand flattens back down again. 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. By the time the shaking has ceased and the tsunami has receded, the region will be unrecognizable. 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.

And as we hear in the final video below as was reported in this July 12th story over at Strange Sounds, the San Andreas Fault and the Pacific Northwest are not the only areas overdue for a killer quake, with the 150-mile-long New Madrid Seismic Zone way overdue for a monstrous quake which experts recently warned has a terrifying 40% chance to blast in the next few decades, impacting 7 states – Illinois, Indiana, Missouri, Arkansas, Kentucky, Tennessee and Mississippi – with 715,000 buildings damaged and 2.6m people left without power.

Way back in 1811 and 1812, a series of over 1,000 earthquakes rocked the Mississippi River between St. Louis and Memphis. One was so powerful that it caused the river to run backwards for a few hours. The infamous New Madrid earthquakes of 1811-1812 rang church bells in Boston, which is 1,200 miles from St. Louis.
As the Strange Sounds story reports, the New Madrid fault has an impact zone ten times as big as its more famous San Andreas cousin and as this November of 2018 story over at the Fullerton Sun had reported, that threat, and the fact that the New Madrid is already well overdue for its next set of massive quakes, have one US General shaking.:

We're not ready for the next big one.

No one knows when the next "big one" will arrive.

The New Madrid Seismic Zone is buried 100-200 feet underground, according to the Missouri Geological Survey. It's primarily monitored by using seismographs, instruments that can measure earthquakes large and small, to detect the frequency of micro-quakes along the fault.

Seismologist — earthquake scientists — also look at historical data, both recorded by people and in the soil and rock itself, to calculate the frequency of past major quakes along the fault. That allows them to guess how frequently large earthquakes occur along the fault.

The current best guess, the MGS states, is that the NMSZ is about 30 years overdue for a magnitude 6.3 earthquake — one strong enough to damage ordinary buildings and overturn heavy furniture. A magnitude 7.6 earthquake, as serious as the 1811-12 series, may arrive by 2069.

Seismologists project the shockwaves from a magnitude 7.6 quake in the NMSZ would reach Callaway County, resulting in slight-to-moderate damage in well-built buildings and some broken chimneys. However, the disruption to utilities could be severe and lasting.

"I've seen firsthand when there's unrest on the civil side," Danner said. "What happens when you don't have sewer, water, electric and gas for weeks at a time — and you have a population that's well-armed?"

With luck, we won't be finding out any time soon.

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