Scientists know that this scenario has happened repeatedly in the last 10,000 years and will do so again. Oregon State University geologist Chris Goldfinger calculates the chance of a major quake at 40 percent in the next 50 years off the southern Oregon coast. The frequency decreases as you move north, but the nearly 800-mile Cascadia subduction zone, where these quakes originate, could rupture anywhere. The last one wiped out villages. The next one will threaten cities and bring a regional economy to its knees.

Nevertheless, for most of us, the threat seems as likely as getting hit by lightning. We know it could happen, but we don’t take it seriously. It feels remote. “The paradigm shift among the citizens of the Northwest has not yet taken place,” says Bob Yeats, emeritus professor of geology at Oregon State and author of Living with Earthquakes in the Pacific Northwest.

As recently as 30 years ago, most scientists didn’t think a major quake could happen here. But, says Yeats in an upcoming book, evidence from coastal marshes, seafloor canyons, GPS monitoring stations and native traditions tell a compelling story: The western edge of North America is locked against another part of the Earth’s crust, the Juan de Fuca Plate, which is diving beneath us. Like wrestlers in mortal combat, they occasionally break their hold on each other and lurch into a new position. Geologists have given such events a name right out of Saturday night wrestling — “megathrust.” When it happens, the landscape vibrates like a bass drum. Seismic waves pulse through the crust for three minutes or more. Some types of soil liquefy and spread out. Bridge and building foundations get pushed out of alignment. Other soils could amplify the shaking from below, subjecting buildings, especially high-rises, to even more violent motion.

Lifelines

Scott Ashford has seen the consequences of these quakes in Chile, Japan and New Zealand: buildings and bridges tilted and broken like toys, beachfront tourist towns reduced to rubble, pipelines squeezed out of the ground like toothpaste out of a tube, businesses closed or forced to relocate.

“Many of Oregon’s lifeline providers have shared research needs, whether it’s to improve our ground motion predictions, to assess liquefaction potential of Oregon soils or to develop retrofit technologies for our legacy systems.”

— Matthew L. Garrett, Director, Oregon Department of Transportation

The Oregon State Kearney Professor of Engineering is determined to soften the blow when Oregon’s turn arrives. In 2010, after viewing damage from a megathrust quake in Chile, Ashford developed the idea for the Cascadia Lifelines Program, a consortium of Oregon businesses, government agencies and universities. The goal is to save lives and to shorten the time it will take for the state and the nation to recover.

“If you look at the effect on the people and at recovery, a key part of our resilience is lifelines,” Ashford says. “Electric power, natural gas, transportation systems, telecommunications, drinking water, sewer. And critical facilities like the Port of Portland and the Portland International Airport. All of these lifeline providers have common challenges to prepare for this next earthquake. None by itself has the financial ability to fund the research necessary. My vision is to pursue research of common interest to develop cost-effective solutions to mitigate the Cascadia earthquake.”

Members of the consortium already include the Oregon Department of Transportation, Portland General Electric, NW Natural (Northwest Natural Gas), the Port of Portland, the Portland Water Bureau and the Bonneville Power Administration. Ashford is lining up others as well. Among their concerns are building standards, landslides, communications and recovery strategies. But first up on their research agenda is an Oregon State study of soil liquefaction, the phenomenon that compounds the damage caused by seismic shaking.

Soil Sleuths

Soils are often named for the places where they’re found. California’s state soil is called San Joaquin. In Washington, Tokul soil is named after a community in King County. Oregon’s state soil is Jory, named for a hill in Marion County where a family of that name settled in 1852. For geotechnical engineers, another local soil poses a potential risk in a megathrust earthquake: Willamette silt.

With a texture midway between sand and clay, this remnant of the ancient Missoula Floods underlies much of the Willamette Valley. From McMinnville nearly to Eugene, bridge piers, roads (I-5, U.S. Highway 99) and pipelines run through or on top of Willamette silt. It carries railroad tracks and electric transmission lines. Large parts of Salem sit on it, as do Albany, Corvallis and Sweet Home. It is up to 130 feet deep in some places.

“We don’t really know anything about how Willamette silt responds to earthquakes,” says Ben Mason, an assistant professor of civil engineering at Oregon State. What he does know is that, as soils go, it doesn’t take much water for it to change from being dry and crumbly to taking on the properties of a liquid. “It has a low plasticity index. What that means is that it can liquefy during an earthquake,” he says. At least theoretically.

To find out for sure, Mason has collected Willamette silt from the Oregon State campus. Last winter, he and a colleague, Li Zheng from the Nanjing Hydraulic Research Institute in China (Li wants to know how earthen dams will perform during an earthquake), placed soil samples the size of hockey pucks in a device that simulates conditions deep underground. They subjected the samples to repeated, precisely controlled cycles of shaking. As a piston shook the sample, simulating seismic waves, sensors measured changes in volume and in water pressure inside the soil.

As the shaking continued, “the water pressure builds up, builds up and builds up and eventually the soil will act like a liquid,” says Mason. “And that’s when we say liquefaction happens.” In effect, he explains, soil structure breaks down, water oozes from pores where it had been bound and the soil turns into a mass with the consistency of pea soup.

We can see liquefaction in action when we walk on a beach, Mason adds. “If you run, you cause these minor liquefaction events. It’s a very dynamic load hitting the sand.” Water is forced out from between the grains and pools briefly on the surface. In contrast, water underground has nowhere to go. As Mason’s experiments show, pressure rises. The question is: Will it get high enough to trigger liquefaction? If it does and the soil happens to be on a slope, it can spread out, jeopardizing any structure that is in the way, such as a bridge pier, building foundation or pipeline.

Mason’s experiments are the first to be supported by Cascadia Lifelines Program funding. His lab is one of the few on the West Coast with the ability to subject soils to a wide range of precisely controlled earthquakes. His “cyclic simple shear” device can be programmed to mimic seismic waves with varying duration and strength. With accurate information about Willamette silt, engineers will be able to design structures that can minimize the damage from the possibility of soil movement caused by liquefaction. Engineering firms are already contacting him to test soil samples for project design purposes.

Buildings and Bridges

Most schools, city halls, bridges, commercial buildings and other structures in Oregon were built before the possibility of big earthquakes was taken seriously. “We don’t know how these buildings will perform (in an earthquake),” says Andre Barbosa, an Oregon State structural engineer. “We have a very rough idea. We know by year and type of construction, whether this or that building may behave well or not so well. But we don’t really know.”

Because seismic stresses were not even recognized in the state’s building codes until 1974, our infrastructure and architectural heritage are highly vulnerable. According to the Oregon Resilience Plan, a report produced by the Oregon Seismic Safety Policy Advisory Commission (OSSPAC) in 2013, nearly half of 2,193 schools assessed in the state have a high to very high potential for collapse. More than a third of the 2,567 bridges in the state highway system were built with no seismic considerations. All nine of Portland’s bridges over the Willamette were built before seismic codes were in force, although some have been strengthened.

But estimating vulnerability is only the start, says Barbosa, who specializes in structural performance in earthquakes. Engineers also need to evaluate strategies for retrofitting old structures and improving standards for new construction. Toward that end, Barbosa conducts experiments on building and bridge components in the Oregon State structures lab, which boasts the second-largest “strong floor” on the West Coast. It allows researchers to simulate earthquake forces up to 1 million pounds on frames up to two stories high. In a project for the Oregon Department of Transportation, Barbosa is evaluating the performance of high-strength reinforcing steel (aka “rebar”) to resist long-duration shaking.

That fills an important need in the Northwest where subduction zone earthquakes are likely to last three to five minutes or more. In contrast, crustal earthquakes, such as those along the famed San Andreas Fault in California, typically last 30 seconds or less. The difference adds up to higher demands on buildings, especially where the frequency of the seismic waves matches a structure’s internal characteristics.

“The main objective of our modern building codes is life safety,” Barbosa adds. “We design structures so that people can evacuate in case of strong shaking. The structure can vibrate back and forth, but it is designed not to collapse. That’s the life safety design approach.”

In addition to living in earthquake country, Barbosa has a personal connection to such events. He grew up in Lisbon, Portugal, which suffered a cataclysmic earthquake and tsunami in 1755. Geologists now estimate that it approached the strength of the 1700 megathrust earthquake in the Pacific Northwest. Since then, Portugal and the Northwest have experienced thousands of smaller quakes centered in local faults, but there have been no large events of the kind seen recently in Chile and Japan. “The problems we have in Portugal are the same as we have here in Oregon,” he says. “The return period for large earthquakes is very long. People just don’t remember.”

Nevertheless, Oregon is taking a leadership role in planning. Elsewhere, agencies and regions (the San Francisco Bay Area) have developed a holistic approach to resilience, but Oregon is the first to do so at the state level. “Through OSSPAC,” says Barbosa, “Oregon is doing something that is amazing.”

Sliding Slopes

When Michael Olsen pulls up a map of the Oregon Coast Range on his computer, he sees wide swaths of red dots. Each one represents landslide-prone areas identified through the highly accurate lens of a remote sensing technology known as LIDAR (“light detection and ranging”). The Oregon State civil engineer and Hoffman Faculty Scholar specializes in the emerging field of geomatics, which is land surveying on steroids. Geomatics practitioners analyze landscapes by combining remote sensing data (from the ground, the air or planetary orbit) and large spatial datasets for soils, vegetation, precipitation, streams and other features.

In the Coast Range, Olsen and his graduate students are assembling LIDAR data and layering it with what engineers know about the terrain. Working with the Oregon Department of Transportation, their goal is to estimate the likelihood of earthquake-triggered landslides near highways that link the I-5 corridor with coastal communities.

These mountains might be beautiful, but Olsen’s picture isn’t pretty. “The Coast Range consists of very loose soils that are of very poor quality. They don’t have a lot of strength to them,” he says. In an emergency, “barriers along these lifeline corridors would be a big problem. Even a small landslide can close down a road for a day or two.”
And it doesn’t take much to start Coast Range soils moving. Based on the locations of previous slides and knowledge of soil types, it appears that slopes as low as 10 to 15 percent are vulnerable to sliding. “That isn’t that much. It’s pretty scary that it’s that low,” Olsen says.

Landslides are hardly a new phenomenon in Oregon, but they are more common in some years than in others. The winter storms of 1996-97 generated an estimated 9,500 landslides, mostly in western Oregon. Scientists at the Oregon Department of Geology and Mineral Industries (DOGAMI) have calculated that, while economic losses exceed $10 million in a typical year, they exceeded $100 million that winter.

Although all Coast Range roads pass through slide-prone terrain, some may be less vulnerable and easier to re-open than others. Such information, says Olsen, will help ODOT prioritize roads for earthquake recovery purposes.

A Statewide Effort

By coordinating these and other research investments, Cascadia Lifelines meets an important need for state agencies and utility companies and fills a critical niche in statewide preparedness efforts. Spurred by the state Legislature, scientists, utility companies and agencies are evaluating risks and identifying solutions to mitigate the most significant impacts of the next megathrust earthquake. Schools and other public buildings have been assessed, and retrofits have begun. Roadways are being ranked for vulnerability to landslides and bridge failures. On the coast, evacuation routes are being marked to help coastal residents and visitors escape the tsunami zone.

“Given the nature and wide-ranging impact of seismic activity, it is appropriate that a consortium of organizations engaged in building, operating and maintaining critical infrastructure in Oregon could work together to identify and address concerns about improving seismic resilience.”

— Grant Yoshihara, Vice President, NW Natural

In 2011, Oregon’s Earthquake Commission (aka the Oregon Seismic Safety Policy Advisory Commission or OSSPAC) assembled experts to lay out the risks and recommend a series of steps for the next 50 years. It released a final report — The Oregon Resilience Plan — last February. “The broad picture of what needs to be done is pretty straightforward,” says Ian Madin, chief scientist for DOGAMI and an Oregon State alum who helped to lead the planning. “We need to strengthen our infrastructure so that it physically resists the effects of the earthquake, so that it is either undamaged or easily repairable.”

Engineers know how to design earthquake-resilient structures, say Madin and Ashford. They can “harden” foundation soils to resist liquefaction and construct bridges and buildings that can survive shaking. Such measures carry a stiff price tag, but the return on investment can be positive. For example, says Ashford, after the earthquake in Christchurch, New Zealand, earthquake preparedness steps saved $10 for $1 spent.

Power to Recover

Ultimately, recovery is about more than engineering. It is about assistance for a traumatized citizenry, strategies for keeping small businesses afloat, security to prevent looting, radio systems that will work after cell-phone towers and land lines go down and policies that allow restoration projects to be fast-tracked. In Chile, Ashford adds, electricity was crucial for recovery efforts. Water pumps in rural areas, for example, couldn’t even be tested until power was restored. In New Zealand, homeowners insure against earthquakes as well as fire.

The government helped businesses get back on their feet by creating a temporary mall out of shipping containers. Grants kept paychecks flowing to employees who otherwise would have qualified for unemployment. Some businesses provided food and fuel to employees’ families so that workers could focus on the job of rebuilding without worrying if their loved-ones were safe.

Individuals need to prepare as well. “I’m a big believer in personal responsibility,” says Ashford. He has installed an electrical generator port on his home, keeps extra medication on hand and fills his truck’s fuel tank when it hits half empty. “Every family needs to be prepared to be on their own for a few days. Every community needs to be prepared to be on its own. If you are expecting the government to come in immediately with assistance, it may take many days or weeks for that help to arrive.”

But Yeats, an emeritus professor in geosciences at Oregon State University, has been mapping fault lines for more than 40 years and can tell you when a quake is overdue. And he can tell you what areas of the world are most likely to suffer the greatest impact when one occurs.

Robert Yeats has led public workshops in earthquake-prone areas around the world.

So it wasn’t a fluke when Yeats told a reporter from Scientific American last year that Port-au-Prince straddled a time bomb, not a week before a magnitude 7.0 earthquake devastated the city. Yeats drew his conclusion from decades of mapping fault zones around the world and from understanding that when builders ignore geological processes, things can go horribly awry.

“I don’t have any second sight. It’s something anyone working on this problem would be aware of,” says Yeats. “It’s just a question of, ‘Do you keep that to yourself, or do you tell people about it?’”

Yeats has crafted a good portion of his career around telling people about it. Consider it his personal mission, but Yeats isn’t into doom. He’s wants to make sure that people recognize the danger and do something about it.

That’s why he wants people to participate in the Great Oregon ShakeOut, the first statewide earthquake drill on Jan. 26. Yeats helped champion the event to increase the public’s awareness of what a major earthquake would be like. But his involvement runs even deeper than that. The ShakeOut might not have come to Oregon at all if it hadn’t been for OSU researchers, including Yeats, who in the mid-1980s were among the first to suggest that Oregon is subject to massive subduction zone earthquakes.

79 and Active

Yeats, who is 79 years old and still active in earthquake research, has played a key role in the field. His technique of using oil-well data to map faults in three dimensions has provided the Northwest with a more detailed look at the extensive, active fault network in the region. It also gave Yeats a niche in mapping faults worldwide: No one had used the wealth of oil-well data to identify volatile seismic areas.

His outreach work has been passionate and consistent for more than 20 years. He has written books about earthquakes for non-scientists. He’s taught students from California to the Northwest about earthquake risk. He’s advised governments and community groups. He’s made sure his findings and practical advice have received news media attention.

Meanwhile, Yeats’ protégés have made groundbreaking discoveries. To date, he has mentored more than 50 graduate students. Among them is OSU professor of marine geology and geophysics Chris Goldfinger, whom Yeats advised during the latter’s graduate studies at OSU. Goldfinger has used Yeats’ mapping techniques in part to demonstrate that the Northwest has experienced repeated, significant earthquakes over the past 10,000 years — and that we will experience them again. Goldfinger also models the paths that tsunamis could take if they strike the Northwest coast after a major Cascadia subduction zone quake.

“A lot of scientists stay detached from the meaning of what they do, and from the outcome. Bob didn’t have that barrier,” says Goldfinger. “I like the personal model that makes everything tie together and be more relevant to what you do every day. And Bob’s still doing that.”

Another of Yeats’ former students is Andrew Meigs, OSU associate professor of geology, who is carrying on Yeats’ 30 years of work in the Pakistani Himalayas.

Yeats finds hope for the future in OSU research on earthquake and tsunami awareness. “OSU is really a leader in this arena,” he says. It leads to practical applications: tsunami evacuation plans and earthquake resistant bridges.

Yeats has been so important to his students that 30 of them donated a total of $500,000 to create an endowed professorship in his honor.

Get Ready and ShakeOut

Saving lives is what the Great Oregon ShakeOut is about, and that’s why it’s important to Yeats.
On Jan. 26, thousands of people throughout Oregon participated in a drill to help them understand how to prepare for, respond to and recover from a catastrophic earthquake. The National Science Foundation, Federal Emergency Management Association and U.S. Geological Survey sponsored the event.

For Yeats, though, it isn’t enough. He wishes every Oregonian would participate. But considering that the last major Northwest earthquake occurred more than 300 years ago, it’s not only easy for people to overlook the threat, it’s nearly impossible for them to conceive of it.

At the Cascadia subduction zone, the Juan de Fuca plate dives beneath North America (illustration courtesy of the Oregon Department of Geology and Mineral Industries

“We had a really bad one in 1700, but that was forever ago to most people here,” Yeats says. Jan. 26, in fact, was the 311th anniversary of that big quake, which was so strong, it is believed to have altered the physical makeup of the Oregon and Washington coasts to a stunning degree. Written records from Japan, which was hit by a 30-foot tsunami, and geological evidence on the Oregon Coast detail its severity.

And that’s what Yeats wants people to understand. Severe earthquakes like that don’t just happen once in a region. They happen repeatedly, and the key to minimizing damage and casualties is realizing that the Northwest is a region rife with seismic activity — and being ready for it.

In other regions, the threat may feel real because large earthquakes have happened more recently. Californians have photos of the 1906 San Francisco earthquake, which led to a fire that devastated the city. They have images of the Cypress Street Viaduct collapsing in 1989’s Loma Prieta quake branded into their memories. They have their own experiences with waking in the night to shaking. It’s why more than 6 million California residents were expected to participate in their ShakeOut.

1971, San Fernando Valley

California earthquakes, in fact, were instrumental in Yeats’ transformation from geologist to messenger. In 1971, he was teaching at Ohio University after working as a petroleum geologist for Shell Oil in southern California. In February of that year, a catastrophic earthquake struck the San Fernando Valley, where he had thought of relocating his family. “It just shows how fate works,” Yeats says. “If I had moved there, my wife and children would have all been there, in their house. And possibly in danger of losing their lives.”

It made Yeats think of all the mapping data he and others were amassing for the oil industry, and using it to determine where the most volatile fault lines were throughout the world. For the next three decades, mapping faults in three dimensions became Yeats’ specialty. It carried him to a department head position at Oregon State in 1977 and around the world, from New Zealand to Afghanistan to Japan.

But Yeats began to wonder if publishing papers and discussing his findings with the scientific community was enough. “I realized what we did — mapping faults — people needed to know about, whether it’s the citizens of Port-au-Prince or the Oregon Coast,” Yeats says. “Because we have a hazard there, and we have to take it seriously and do the preparations necessary so people won’t get killed.”

Once the scientific community understood that there was an earthquake hazard in the Northwest, a conclusion in which Yeats was instrumental, he began to educate the public. He sent the message through news releases and talked to reporters about the potential for Cascadia subduction zone earthquakes. In the mid-80s, he was raising public awareness of earthquake problems in a region that was relatively quiet, unlike California.

Yeats created an undergraduate course at Oregon State called “Living with Earthquakes in the Pacific Northwest.” He taught students how the Northwest’s earthquake vulnerability was discovered and how society responded to that threat when it came to state legislation and to the practical aspects of daily life such as building codes and insurance premiums. The class also taught students how they could respond individually and within their communities to the threat.

Eventually, his notes turned into a book of the same name, published by the OSU Press in 1998. “The book, now in a second edition published in 2004, focuses on getting people to do simple things,” Yeats says. “Bolt older houses to the foundation. Make sure there’s a wrench near the intake valve on your gas meter. Have a disaster plan.”

Although Yeats wrote the book for students, it reached a wider audience: legislators, high school principals, local officials and emergency managers. And it’s still in print, just as his class is still being taught online and in the classroom. Yeats recently gave a copy of the book to the city manager of Bend, Ore., a city that straddles an active fault line.

In 2001, Yeats published the even more ambitious, “Living with Earthquakes in California.” The book describes how California admitted to its “earthquake problem” and helps communities and individuals to prepare.

Yeats also talks to local groups and consults with cities all over the region about infrastructure and new development projects. He’d like Oregon to catch up with California in terms of seismic awareness. “Oregon has upgraded building codes, but we still need to do what California has done and make an inventory of unsafe buildings. Oregon has not done that,” Yeats says.

2011, Cannon Beach to Kabul

But towns in Oregon, such as Seaside and Cannon Beach, regularly conduct tsunami drills with elementary school students. Statewide, and the Department of Geology and Mineral Industries is taking the lead in raising earthquake awareness. “I’d say the general person on the street is aware that we’re in earthquake country. When I first came here, that wasn’t the case,” Yeats says. “Oregon’s had some real leadership, but we have a long way to go.”

Yeats says he can get through to some people, but alerting the public to a potential danger isn’t the same as telling them about a danger that has a date, time and place. And telling people doesn’t mean they’ll listen. It’s a dilemma he’s faced throughout his professional career. It’s human nature, Yeats says, to be unable to appreciate a threat that seems abstract, or that might happen centuries into the future. It’s a little like the children’s book character Chicken Little warning that the sky is falling.

“You ask people the same questions you’d ask the president of Haiti a week before the quake: ‘You’re on a fault running outside your city. It’s going to go. It’s going to kill a lot of people.’ But they say, ‘Is it going to happen during my term of office? You’re not sure? Thanks for your time.’ Can you blame them?” he asks.

Yeats persists in this frustrating mission because, he says, “People are responsive, but the general public has to be reminded, and you have to keep reminding them.”

His latest book, Active Faults of the World, will be published by Cambridge University Press in 2011. The book is part of an international collaboration to create an online worldwide active-fault database. With it, Yeats hopes he can help prompt officials in other earthquake “time bomb” spots — Kingston, Jamaica; Tehran, Iran; Kabul, Afghanistan; Karachi, Pakistan — to take precautionary action. He hopes his message reaches people before it’s too late.

Researchers at Oregon State University – who in the mid-1980s were among the first in the nation to suggest that Oregon is subject to massive subduction zone earthquakes – have helped define the faults placing Oregon residents at most risk, supported efforts to boost building codes, and more recently have studied earthquake disasters all over the world to identify what makes the difference between tragedy and survival.

“It’s been a long struggle to convince Oregonians that these risks are real, that it will happen here and we have to prepare for it,” said Bob Yeats, a professor emeritus of geology at OSU and international leader in earthquake science and history. “Earthquakes can’t be predicted with any precision, but they can be prepared for, we can save lives, and the Oregon ShakeOut is a great thing to help raise the awareness of what we should do.”

That preparation, OSU experts say, should be reflected in everything from personal knowledge to homeowners analyzing the risk areas in their own residences, disaster plans, community infrastructure, well-enforced building codes, zoning considerations and better public awareness of risks.

Yeats wrote a book published in 2004, Living with Earthquakes in the Pacific Northwest, which outlines in more detail many of the same issues that will be explored in the Great Oregon ShakeOut.

The catastrophic event a year ago in Haiti provides perhaps the most vivid illustration of earthquake disasters, and a 7.2 magnitude earthquake in southwest Pakistan on January 19 was a reminder of the Earth’s near-constant tectonic activity. But these events are just some of many and can have markedly different results.

• In 2003, an earthquake of magnitude 6.6 occurred on a strike-slip fault near Bam, Iran, which was constructed largely of aging mud/brick structures. Almost 90 percent of the buildings were destroyed and almost 40,000 people died, nearly one out of every four residents.

• A few days later, the San Simeon earthquake in California hit on a reverse fault with magnitude 6.5. No buildings with even partial seismic retrofitting collapsed, and only two people died.

“We saw essentially the same thing with the recent 7.1 earthquake in New Zealand, where they have strong building codes and no one died,” Yeats said. “And of particular interest for us in Oregon should be the Chilean subduction zone earthquake last February, which was huge at magnitude 8.8 and is quite similar to what we may expect on the Oregon Coast during its next subduction zone quake.”

According to Scott Ashford, professor and head of the School of Civil and Construction Engineering at OSU, Chile is actually a case of what Oregon should aspire to.

This image shows the general motion of Pacific Northwest landforms as the terrain is squeezed and moved by tectonic forces. (Graphic courtesy of Rob McCaffrey, Bob King and Suzette Payne, Portland State University)

“Because it has had subduction zone earthquakes with much more frequency than the Pacific Northwest, the buildings, roads and infrastructure in Chile are actually more earthquake resistant than here in Oregon,” Ashford said.

“There was loss of life in Chile, but all things considered they did pretty well in maintaining what I think of as their lifelines, the roads, bridges, power supplies and other things that you most urgently need in a disaster,” he said. “We haven’t made the progress in that area that we should, and I think we’re already starting to forget some of the lessons and awareness we had just a year ago after the Chilean quake.”

Ashford said a good first step would be to assess all of the state’s vulnerabilities in the event of a major earthquake, and then prioritize which areas to tackle first with whatever funding can be made available.

Things could be worse, and in many parts of the world they are. Later this spring Yeats will publish another book, Active Faults of the World, which will explore the many cities around the world which have the potentially disastrous combination of poor construction practices, heavy population and major, active earthquake faults. Ranging from Kabul (Afghanistan), to Karachi (Pakistan), Istanbul (Turkey), Tehran (Iran), Caracas (Venezuela), and Kingston (Jamaica), there are many more tragedies waiting to happen.

The good news, OSU researchers say, is that Oregon, like Chile, does not fit that desperate category – but that’s not saying there isn’t room for improvement.

“As this statewide drill illustrates, we’re just now beginning the type of widespread, public education about earthquake risks and preparation that we’ve needed for a long time,” Yeats said. “That should continue permanently, but there’s also more that could be done.”

Among possible improvements, the OSU researchers said, might be:

• Crustal faults in Oregon, aside from the Cascadia Subduction Zone, should be better identified;

• It could be required that the sites of proposed construction be evaluated for earthquake fault and landslide hazards, as is done in California;

• The landslide risks associated with earthquakes should also be better considered in housing, road and infrastructure decisions;

• More attention should be paid to “lifeline” infrastructure such as electricity and gas supplies, water and sewers, roads and bridges;

• Existing programs of seismic retrofitting should be encouraged and expanded;

• More work could be done with LiDAR sensing technology to identify faults and landslides, which is available in Western Oregon through the Oregon Department of Geology and Mineral Industries;

• Efforts should be expanded to educate not just residents but also tourists on the Oregon Coast about the risks and disaster plans associated with subduction zone earthquakes and resulting tsunamis. Many of those who died in the Chilean earthquake were tourists on summer vacation.

Although the subduction zone earthquake issues have gotten most of the recent headlines, Yeats said, the risks from crustal faults in the Pacific Northwest should not be underestimated. The Corvallis Fault runs right underneath a local high school and through residential areas. The Portland Hills Fault runs through downtown Portland. It’s not known whether either of these faults is active or not.

Similar crustal faults underlie both Tacoma and Seattle, the other two major urban areas in the two states, and in one case near Seattle a major public works facility is being built right on top of a fault.

“There are people all over the Pacific Rim who understand and have prepared for earthquake disasters they know will happen,” Yeats said. “Now we’re gaining a better understanding of those risks here in Oregon and Washington. There’s still a lot to do, but it’s a good start.”

March 15, 2010: “The Bridge Team’s goal for today was to determine the geographical extent of bridge damage from the Chilean earthquakes. We did this by driving nearly 450 miles south along Route 5 (the Pan American Highway) from Santiago to Temuco, keeping along the outer edge of the zone of strong shaking (about 50 miles or so inland). To put this into Pacific Northwest context, it would be very similar to driving from Seattle to southern Oregon along I-5 after a Cascadia Subduction Zone earthquake off the Oregon/Washington coast.”
— Blog post from OSU civil and construction engineer Scott Ashford

Ashford visited Chile as a member of the international Chile Earthquake Reconnaissance Team sponsored by the Earthquake Engineering Research Institute. The quakes that have devastated Chile and Haiti in recent months, he notes, are reminders that Oregon, too, sits poised for heavy shaking. The Cascadia Subduction Zone shifts abruptly every 300 to 400 years or so, and the next time it does, experts predict destruction and dislocation from the Pacific shoreline inland to Portland and the Willamette Valley. A tsunami could follow in the earthquake’s wake.

To help Oregonians prepare, Oregon Sea Grant outreach specialist Patrick Corcoran is working with coastal communities. “We may have as little as 15 minutes’ warning for a potential tsunami, and the damage from an earthquake could be immediate,” says Corcoran, who coordinates the Coastal Storms Program at OSU. “We all need to be prepared to help ourselves.”

Ashford and Corcoran are among more than a dozen OSU faculty who are sharing their expertise in engineering, geology, communications and marine sciences with Chilean colleagues.

More information on tsunami preparedness is available at OSU Extension.

In one of the Earth's most active fault zones, OSU geoscientist John Nabelek and colleagues are defining the forces that created Mt. Everest and threaten millions of people. (Photo courtesy of John Nabelek)

On a computer generated diagram of seismic profiles from Nepal and Tibet, John Nabelek traces a thin blue line. “That’s the interface between the Indian and the Eurasian tectonic plates,” he says. The earthquake-prone, mountainous terrain above it is home to an estimated 40 million people.

“It is very steep. In earthquakes, landslides come tumbling down,” says Nabelek, an associate professor in Oregon State University’s College of Oceanic and Atmospheric Sciences. “Construction is not up to par, so there, you’re looking at a huge disaster.”

With support from the National Science Foundation (NSF), Nabelek leads an international team of scientists on a quest to understand the underlying geology of the Himalayas. In 2009, they created the most complete seismic image of the Earth’s crust and upper mantle in the region and discovered some unusual geologic features that may explain how it has evolved. The study is known as Hi-CLIMB, Himalayan-Tibetan Continental Lithosphere during Mountain Building.

“The research took us from the jungles of Nepal, with its elephants, crocodiles and rhinos, to the barren, wind-swept heights of Tibet in areas where nothing grew for hundreds of miles and there were absolutely no humans around,” Nabelek says. “That remoteness is one reason this region had never previously been completely profiled.”

Waterbed Geology

A lack of scientific consensus on how two continental plates collide has led to competing theories about the Himalayas. Some researchers have proposed that the heat generated by the collision has melted so much rock that the Tibetan plateau floats above it as though on a waterbed.

“There could be small pockets of fluid, but our study shows there are not large amounts of fluid here,” says Nabelek. “The building of Tibet is not a simple process. In part, the mountain building is similar to pushing dirt with a bulldozer, except in this case, the Indian sediments pile up into a wedge that is the lesser Himalayan mountains.”

The interface between the subducting Indian plate and the upper Himalayan and Tibetan crust is the Main Himalayan thrust fault, which reaches the surface in southern Nepal. The new images show that it extends from the surface to mid-crustal depths in central Tibet, but the shallow part of the fault sticks, leading to historically devastating mega-thrust earthquakes.

“The deep part is ductile and slips in a continuous fashion. Knowing the depth and geometry of this interface will advance research on a variety of fronts, including the interpretation of strain accumulation from GPS measurements prior to large earthquakes,” Nabelek adds. The study is continuing with funding from NSF and the Air Force Research Laboratory.

Nabelek also studies the Cascadia subduction zone, in which the relatively dense Juan de Fuca plate dives beneath North America. “The advantage of working in Tibet is that you can get on top of it. You can work on it. With the Cascadia, most of the mega-thrust is offshore about 100 miles.”

His emphasis in Cascadia is in the southern portion of the Juan de Fuca plate offshore from the Oregon-California border, a region known as the Gorda Deformation. Scientists don’t yet know why so much seismic activity occurs in this area. Most of the Juan de Fuca plate is relatively calm.

In another project funded by the NSF-EarthScope program, Nabelek will use the crustal imaging techniques employed in Nepal and Tibet to study the Earth’s crust under parts of Nevada. That project is scheduled to start this summer.

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