Cascadia subduction zone

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In 2011, an earthquake generated a devastating tsunami that was observed across the Pacific and caused tremendous local devastation in Japan. (Photo/Shunichi Koshimura)

By Michael Kuhne – AccuWeather

Stretching more than 600 miles (965 km) along the coastline from Vancouver Island down to California’s Cape Mendocino lies a sleeping, tectonic giant capable of causing massive devastation and drastically changing the face of the Pacific Northwest.

The Cascadia subduction zone rests beneath the waves approximately 62 miles (100 km) offshore where the oceanic Juan de Fuca Plate converges and slides under, or subducts beneath, the western edge of the North American continent.

The same fierce geologic forces which gave rise to the Cascade Range and cemented the region’s place in the Ring of Fire have also been responsible for massive earthquakes, volcanism and catastrophic tsunami events in the past.

Continue reading at AccuWeather: Preparing for the Unpredictable: Megaquake, Tsunami May Forever Alter the Pacific Northwest

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Thomas Leth-Olsen/Flickr

“It is coming. It is a certainty […] more than ten-thousand will die,” says Fox News anchor Shepard Smith

By Shepard Ambellas – INTELLIHUB

PACIFIC NORTHWEST (INTELLIHUB) — “Our operating assumption is that everything west of Interstate 5 will be toast,” a FEMA official told Kathryn Schulz of the New Yorker. “When the next full-margin rupture happens, that region will suffer the worst natural disaster in the history of North America.”, Schulz wrote about an anticipated future mega-quake.

“The worst natural disaster in the history of America is coming […] if I lived right now in the Pacific Northwest I would be considering moving — seriously,” Fox newscaster Shepard Smith warned his audience before going on to explain how a “colossal earthquake and […] tsunami” will likely strike the Pacific Northwest in the not too distant future.

“They [scientists] are all in agreement, it is absolutely coming,” said Smith, “a wall of water […] up to a hundred feet high and up to seven-hundred feet across.

“Houses […] dump-trucks […] schools” will be washed away, “thousands and thousands will not escape.”


Wake Up America/YouTube

“Seattle, Tacoma, Portland, and Olympia, Salem and Eugene wiped out. Altogether about 7 million people and that’s not including tourists.”

“These massive 9.2 earthquakes […] happen at regular intervals […] on average, according to scientists, about every 240 years.”, said Smith.

The segment, which was based on the New Yorker’s write-up, also featured top Astrophysicist Michio Kaku. Shockingly during the broadcast Kaku explained how the Cascadia Fault has already yielded evidence to “scientists” showing how “we could be long overdue for another big one.”

“In the inundation zone we have 70,000 that have almost no clue as to what could happen.”, said Kaku. Unfortunatly Smith already pointed out that the massive tsunami would likely hit about “fifteen minutes” after the earthquake leaving no time for people to flee.

Kaku also offered some advice, saying, “I would think twice” about living in the Pacific Northwest.”

“In the lifetime of some of our viewers they may see Seattle and Portland destroyed,” warned Kaku.

In preparation for such a disaster “Oregon OEM is urging all Oregonians to participate in the Great Oregon ShakeOut earthquake drill on Oct. 15 at 10:15 a.m. It is part of the nation’s largest earthquake drill, and last year more than 390,000 Oregonians participated. Register at http://shakeout.org/oregon/register/ and take steps to make your family safer.” — KTVZ 21

This article first appeared at INTELLIHUB: FEMA Official Warns: “[…] Everything West Of Interstate 5 Will Be Toast”, Massive Natural Disaster Coming

About the author:

Shepard Ambellas is the founder, editor-in-chief of Intellihub News and the maker of SHADE the Motion Picture. You can also find him on Twitter and Facebook. Shepard also appears on the Travel Channel series America Declassified. You can also listen to him on Coast To Coast AM with hosts, both, George Noory on “Chemtrails” and John B. Wells on the “Alternative Media Special“. Shepard Ambellas has also been featured on the Drudge Report, the largest news website in the entire world, for his provocative coverage of the Bilderberg Group. Shepard is an exclusive weapon of Intellihub.

For media inquires, interviews, questions or suggestions for this author, email: shepard@intellihub.com.

Read more articles by this author here.

earthquake

By Chris Carrington

In just 48 hours, South America has been rocked by volcanic explosions and a series of earthquakes.

The news has been full of the 8.2 magnitude quake that struck Chile, but since then they have suffered 27 more quakes of magnitude 5+, three of which were more than 6+ and a 7.6 not long ago at 0553 GMT. On top of this there have been literally dozens of minor quakes.

Panama has had two 6+ quakes some hours apart and numerous smaller shocks. El Salvador, Argentina and Mexico have both experienced 4.2+ tremblors in the last 24 hours and Puerto Rico is currently experiencing smaller quakes of a magnitude between 2 and 3.

Ubina volcano in Peru, quiet for four decades, is throwing up ash which has forced the evacuation of several villages around the base of the mountain.

Ubina is not alone. Reventador in Peru is also erupting as are volcanoes in Mexico (Colima) and Guatemala (Santa Maria, Fuego and Pacaya). Another dozen are showing minor activity and a further 16 are marked as showing signs of unrest. You can see the full list here.

Unknown

The jury is out on whether one part of the Ring of Fire can affect another area of a seismically active belt that runs around the Pacific rim and with so much activity south of the Cascadia Fault I hope they are right.

The Cascadia Fault is a subduction zone, an area where one of the tectonic plates is forced underneath the plate it collides into. In the case of Cascadia, the Juan de Fuca Plate is moving under the North American Plate. These plates have been locked together since 1700, 313 years. A particular feature of the Cascadia Fault is that it doesn’t produce small quakes, it remains still and silent until the pressure gets too much and one of the plates slips, giving rise to a mega-thrust earthquake of massive force. These quakes can be compared to the Indonesian quake of 2004 and the Japanese quake of 2011.

The Cascadia fault is long, very long, just over 800 miles (1300km) in length. Based on the findings of the scientists, the tsunami caused by the 1700 event moved inland for more than 60 miles, wiping out everything in its path. Of course in 1700 Seattle wasn’t there, neither was Vancouver, San Francisco, Portland or any of the other cities and metropolitan areas currently occupied by millions of people.

The Cascadia, courtesy of its length, will give rise to a long quake if the whole fault ‘unzips’ at the same time, as it’s believed to have done in 1700. The first P waves will travel the length of the fracture in a minute or two. The S waves that follow, the ones that cause the real damage, are slower and will cause shaking and movement for about five minutes though their speed can vary depending on the rock they are traveling through.

Any buildings not built to withstand earthquakes will collapse. Depending on the duration and magnitude of the quake it cannot be assumed that even ‘hardened’ buildings will remain standing. Many areas have sedimentary basins under urban sprawl and this amplifies the waves and the damage they cause.

Within approximately 20-30 minutes the tsunami will roll in. Unlike normal waves which have a few yards between them the tsunami waves can have hundreds of miles between them. The entire wall of water displaced when the plates slip hurtles outwards in all directions from the epicenter of the quake. As the waves approach the continental shelf the water at the back of the wave starts to catch up with the water at the front of the wave, which has slowed down as it moves up the incline that marks the start of the continental land mass. Its this that allows the water to build up and give the tsunami its characteristic ‘wall of water’ appearance.

The water will just keep on coming, flowing forward taking almost everything in its path with it. It may or may not be followed by more waves, there is no way to know if it will be a solo wave or a series until it happens. There is also no way to know in advance how deep the water will be. The tsunami caused by an earthquake in Lituya Bay Alaska in 1958 reached 1720 feet. (source)

Surviving an earthquake and tsunami is very challenging, but recognizing that should the Cascadia rupture, a tsunami is almost certain to follow gives you a firm footing to plan from. Don’t wait and see. Subduction earthquakes come into the mega-thrust category, and there are rarely, very, very rarely foreshocks. These faults lie silent for decades, sometimes for centuries before they rip. The forces released are unimaginable as it has been building, unreleased since the last time it ripped, in the case of the Cascadia 1700. 313 years worth of tension that will distort and bend the sea bed. The displacement of water in the ocean above the rupture will send a tsunami out in all directions.

You will have 20-30 minutes to get to higher ground. Knowledge about your location, the terrain, and the distance to higher ground will all impact your survival. All the drills in the world won’t help you if you are faced with a 50ft wall of water.

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Contributed by Chris Carrington of The Daily Sheeple.

Chris Carrington is a writer, researcher and lecturer with a background in science, technology and environmental studies. Chris is an editor for The Daily Sheeple. Wake the flock up!

 

By John Darling

Sitting on a major fault line, Oregon is “like an eight-and-a-half-month pregnancy, due any time now” for a major earthquake, a geologist with the Oregon Office of Emergency Management told an overflow crowd Friday in Medford.

“We’re in the zone, and we’d darn well better get ourselves ready for it,” said Althea Rizzo, geology hazard coordinator for OEM.  “A lot of you may have moved here from California to escape them, but the fact is, Oregon is earthquake country.”

About half the hands went up when Rizzo asked how many had been through a California earthquake.

Rizzo said there’s a 37 percent chance the Big One will happen in the next 50 years.

A major earthquake would cripple transportation on Interstate 5 as  bridges and overpasses collapse from two to four minutes of ground shaking, possible very severe, with stressful aftershocks for weeks.

“It’s going to shake here,” she said. “Single-family homes will bounce off their foundations. Landslides will cause transportation between I-5 and (Highway) 101 on the coast to be cut off for three to five years.”

A big quake will cause liquefaction, in which the ground, if saturated with water, will “turn to pudding,” causing hardware, such as sewer systems, septic lines and gas tanks, to rise up out of the earth.

Lines from Washington state gasoline refineries cross 15 rivers, leaving them vulnerable to quake tremors, she says. Most of these were built in the mid-20th century, with no thought to making them quake-resistant, she says, adding that they would be offline for at least six months.

Electrical power would be down from one to three months until transformers and the electrical grid get going again, she says.

A region’s markets have food enough for only three days, so families should store at least three weeks of nonperishable food — tuna, beans, freeze-dried items — and other vital commodities, such as toilet paper.

Rizzo advocates planning on the household, regional and statewide levels before the inevitable quake emanates from the “big, bad, ugly” Cascadia Subduction Zone, which runs 600 miles from about Eureka, Calif., to the north end of Vancouver Island.

The North American tectonic plate, on which the Rogue Valley rests, is moving southwesterly a couple of inches a year, overriding oceanic plates and building up tension. When the tension is released, she said, it causes far-reaching land quakes and lifts an enormous amount of sea water, which will slam the Oregon Coast with tsunamis.

Partial quakes happen on an average of every 240 years. The last one was in 1700, so it’s been 213 years. Quakes of the entire length of the zone come every 500 to 600 years and governments should expect those to be 9.0 or more on the Richter scale — tremendously devastating.

They cannot be predicted, Rizzo said.

Another blow to Oregon would come if vital utilities and transportation were cut off for so long that major businesses left the state and took jobs and money with them.

A dozen years ago, Oregon authorized $2 billion in bonds to bolster infrastructure in schools, community colleges and emergency services, but the recession, she said, took that off-track.

Rizzo urged several hundred local residents to spread the word to family and friends to take first-aid and Community Emergency Response Team training, store supplies and get to know your neighbors and people who have training and tools.

Communities must assess risks to buildings, roads, power, water and sewer lines, she said, adding that people should learn to “drop, cover and hold” and practice getting to safe places in their homes. Wall art should be screwed down, big furniture, water heater and bookcases secured, and heavy items kept close to the floor, not up high where they could fall on people.

“You need to practice this over and over because when it’s happening you’re not going to be able to think,” she said. – Mail Tribune

Cascadia Earthquake Model

 

The Great Oregon Shake-Out will be held at 10:17 a.m. Oct. 17 to do the “drop, cover and hold on” drill. Details of this and all other quake information can be found at www.oregon.gov/omd/oem.

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NOAA/NGDC image of the Atlantic crustal age of the ocean floor. Geologists have detected the first evidence that a passive margin in the Atlantic ocean is becoming active. The team mapped the ocean floor and found it was beginning to fracture, indicating tectonic activity around the apparently passive South West Iberia plate margin. (Credit: Mr. Elliot Lim and Mr. Jesse Varner, CIRES & NOAA/NGDC)

A new subduction zone forming off the coast of Portugal heralds the beginning of a cycle that will see the Atlantic Ocean close as continental Europe moves closer to America.

Published in Geology, new research led by Monash University geologists has detected the first evidence that a passive margin in the Atlantic ocean is becoming active. Subduction zones, such as the one beginning near Iberia, are areas where one of the tectonic plates that cover Earth’s surface dives beneath another plate into the mantle — the layer just below the crust.

Lead author Dr João Duarte, from the School of Geosciences said the team mapped the ocean floor and found it was beginning to fracture, indicating tectonic activity around the apparently passive South West Iberia plate margin.

“What we have detected is the very beginnings of an active margin — it’s like an embryonic subduction zone,” Dr Duarte said.

“Significant earthquake activity, including the 1755 quake which devastated Lisbon, indicated that there might be convergent tectonic movement in the area. For the first time, we have been able to provide not only evidences that this is indeed the case, but also a consistent driving mechanism.”

The incipient subduction in the Iberian zone could signal the start of a new phase of the Wilson Cycle — where plate movements break up supercontinents, like Pangaea, and open oceans, stabilise and then form new subduction zones which close the oceans and bring the scattered continents back together.

This break-up and reformation of supercontinents has happened at least three times, over more than four billion years, on Earth. The Iberian subduction will gradually pull Iberia towards the United States over approximately 220 million years.

The findings provide a unique opportunity to observe a passive margin becoming active — a process that will take around 20 million years. Even at this early phase the site will yield data that is crucial to refining the geodynamic models.

“Understanding these processes will certainly provide new insights on how subduction zones may have initiated in the past and how oceans start to close,” Dr Duarte said. – Science Daily

Story Source:

The above story is reprinted from materials provided by Monash University.

Journal Reference:

  1. J. C. Duarte, F. M. Rosas, P. Terrinha, W. P. Schellart, D. Boutelier, M.-A. Gutscher, A. Ribeiro. Are subduction zones invading the Atlantic? Evidence from the southwest Iberia margin. Geology, 2013; DOI: 10.1130/G34100.1

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Understanding the size and frequency of large earthquakes along the Pacific coast of North America is of great importance, not just to scientists, but also to government planners and the general public. The only way to predict the frequency and intensity of the ground motion expected from large and giant “megathrust ” earthquakes along Canada’s west coast is to analyze the geologic record.

A new study published today in theCanadian Journal of Earth Sciencespresents an exceptionally well-dated first record of earthquake history along the south coast of BC. Using a new high-resolution age model, a team of scientists meticulously identified and dated the disturbed sedimentary layers in a 40-metre marine sediment core raised from Effingham Inlet. The disturbances appear to have been caused by large and megathrust earthquakes that have occurred over the past 11,000 years.

One of the co-authors of the study, Dr. Audrey Dallimore, Associate Professor at Royal Roads University explains: “Some BC coastal fjords preserve annually layered organic sediments going back all the way to deglacial times. In Effingham Inlet, on the west coast of Vancouver Island, these sediments reveal disturbances we interpret were caused by earthquakes. With our very detailed age model that includes 68 radiocarbon dates and the Mazama Ash deposit (a volcanic eruption that took place 6800 yrs ago); we have identified 22 earthquake shaking events over the last 11,000 years, giving an estimate of a recurrence interval for large and megathrust earthquakes of about 500 years. However, it appears that the time between major shaking events can stretch up to about a 1,000 years.

“The last megathrust earthquake originating from the Cascadia subduction zone occurred in 1700 AD. Therefore, we are now in the risk zone of another earthquake. Even though it could be tomorrow or perhaps even centuries before it occurs, paleoseismic studies such as this one can help us understand the nature and frequency of rupture along the Cascadia Subduction Zone, and help Canadian coastal communities to improve their hazard assessments and emergency preparedness plans.”

“This exceptionally well-dated paleoseismic study by Enkin et al., involved a multi-disciplinary team of Canadian university and federal government scientists, and a core from the 2002 international drill program Marges Ouest Nord Américaines (MONA) campaign,” says Dr. Olav Lian, an associate editor of theCanadian Journal of Earth Sciences, professor at the University of the Fraser Valley and Director of the university’s Luminescence Dating Laboratory. “It gives us our first glimpse back in geologic time, of the recurrence interval of large and megathrust earthquakes impacting the vulnerable BC outer coastline. It also supports paleoseismic data found in offshore marine sediment cores along the US portion of the Cascadia Subduction Zone, recently released in an important United States Geological Survey (USGS) paleoseismic study by a team of researchers led by Dr. Chris Goldfinger of Oregon State University.

In addition to analyzing the Effingham Inlet record for earthquake events, this study site has also revealed much information about climate and ocean changes throughout the Holocene to the present. These findings also clearly illustrate the importance of analyzing the geologic record to help today’s planners and policy makers, and ultimately to increase the resiliency of Canadian communities. “

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Researchers say a massive earthquake and tsunami could soon strike the Northwest US coast, killing more than 10,000 people, flooding entire towns, and causing economic damages totaling $32 billion.

An alarming report published by the Oregon Seismic Safety Policy Advisory Commission warns about the dire effects of the quake and claims that it is imminent and could strike anytime. The report, which was compiled by a group of more than 150 volunteer experts, was requested by the Oregon legislature in order to adequately prepare for the looming disaster.  

The last high magnitude earthquake in the region occurred in the year 1700 in the Cascadia Subduction Zone. The quake had a magnitude between 8.7 and 9.2, and geologists in 2010 predicted that there is a 37 percent change of another suck quake occurring within 50 years. The new report claims that there is a 100 percent chance of a monster earthquake occurring in the region – but scientists don’t know when.

“This earthquake will hit us again,” Kent Yu, an engineer and chairman of the commission, told lawmakers. “It’s just a matter of how soon.”

Jay Wilson, vice chairman of the commission that put together the report, told AP that “we’re well within the window for it to happen again.”

With no time frame for the predicted earthquake, Oregonians need to be constantly prepared for one. The report warns of death and devastation ranging from British Columbia to Northern California, the worst of which will strike Oregon.

“Oregonians as individuals are underprepared,” Maree Wacker, chief executive officer of the American Red Cross of Oregon, told AP.

An earthquake, together with the resulting tsunami, could leave Oregonians withoutwater, power, heat, telephone services, and in some cases, gasoline. After a deadly earthquake and tsunami hit Japan in 2011, lawmakers grew concerned that a similar disaster could occur in the US. The report says that geographically, Oregon and Japan are almost identical – but that Japan was far more prepared than Oregon would be if it faced the same fate.

The most recent report is not the first warning of an imminent high-magnitude quake. In 2012, researchers at Oregon State University published a study concluding that there is a 40 percent chance of a major earthquake in the Coos Bay, Ore., region during the next 50 years.

The Northwest US is long overdue for an earthquake, and it’s only a matter of time before the coast once again witnesses a quake with a magnitude higher than 8.0.

“By the year 2060, if we have not had an earthquake, we will have exceeded 85 percent of all the known intervals of earthquake recurrence in 10,000 years,” Jay Patton, co-author of the Oregon State University’s research, said in a press release. “The interval between earthquakes ranges from a few decades to thousands of years. But we already have exceeded about three-fourths of them.”

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