Earthquake near a major city with death toll 'unprecedented in human history' a matter of time: Professor Iain Stewart

by: Anthony Marx / The Courier-Mail

• Mega-cities built on fault lines
• More people living in danger areas
• Amazing map: A century of earthquakes

IT'S only a matter of time before a huge earthquake strikes a major city and results in a death toll "unprecedented in human history".

Well-known Scottish scientist Iain Stewart delivered that grim prediction yesterday in Brisbane during an address to a global geology conference.

Professor Stewart, a geologist and academic who has gained fame for multiple BBC television series on the planet, said the risk of disaster has grown because a growing number of mega-cities are built on or near major earthquake faults.

Large settlements since antiquity have been based on these fault lines because they also help provide water and are usually located near flat plains ideally suited for growing crops.

This "fatal attraction" to dangerous areas was "actually a good thing", because historically the trade-off was worth it since earthquakes were rare and most cities were not that large, he said.

While earthquakes today were often less destructive because of improved building codes, more people were affected because cities were larger, Prof Stewart told delegates at the 34th International Geological Congress.

Despite the danger of such hazards, people were still drawn to earthquake-prone California and the US gulf states, which were routinely hit by hurricanes.

Although it might seem that the number of natural disasters around the world is increasing, there are simply more people living in harm's way, and that fact creates the illusion. "We create the template that brings these disasters," Prof Stewart said.

Similarly, people want to live only 20m from the beach, even in regions liable to be struck by tsunamis. Even after properties have been destroyed, many owners vow to rebuild.

Further research was needed to understand why people continued to have such a high threshold for living in danger zones and why they often chose to ignore the science that could save their lives, he said.

‘The clock is ticking’: ‘Megathrust’ West coast earthquake could resemble Japan’s, studies say

by Randy Boswell

Two separate geological studies suggest the earthquake hazard in the transboundary region of the Pacific Coast of North America — including southern British Columbia — is significantly greater than previously believed, with both teams of U.S. scientists urging heightened readiness for a future offshore “megathrust” event that could compare with the one that triggered Japan’s catastrophe last year.

In one study, a 13-year, comprehensive analysis of the Cascadia earthquake-prone zone between Vancouver Island and Northern California, a team of researchers led by Oregon State University earth scientist Chris Goldfinger concluded that the “clock is ticking” ahead of a potentially devastating earthquake in the region within the next 50 years.

In a 184-page report published this week by the U.S. Geological Survey, the team compiled a detailed record of earthquakes in the Cascadia region going back to 8,000 B.C.

“Over the past 10,000 years, there have been 19 earthquakes that extended along most of the margin, stretching from southern Vancouver Island to the Oregon-California border,” Prof. Goldfinger stated in a summary of the study. “These would typically be of a magnitude from about 8.7 to 9.2 — really huge earthquakes.”

He added that the southern margin of Cascadia, encompassing southern Oregon and Northern California, “has a much higher recurrence level for major earthquakes than the northern end and, frankly, it is overdue for a rupture.”

But he cautioned: “That doesn’t mean that an earthquake couldn’t strike first along the northern half, from Newport, Oregon, to Vancouver Island.”

Co-author and OSU geologist Jay Patton also emphasized the likelihood of a major quake in the Pacific Northwest in the coming decades.

“By the year 2060, if we have not had an earthquake, we will have exceeded 85% of all the known intervals of earthquake recurrence in 10,000 years,” he said in the overview. “The interval between earthquakes ranges from a few decades to thousands of years. But we already have exceeded about three-fourths of them.”

The second study, which appears in the latest issue of the journal Geology, interprets new fault-zone temperature data along the Pacific Coast to conclude that the probable impact area of the next megathrust quake in the region could extend as much as 55 kilometres farther east than previous studies have suggested — raising the spectre that coastal cities such as Vancouver, Victoria, Seattle and Portland would experience significantly greater-than-expected seismic impacts when the next “Big One” strikes.

“If one is closer to the rupture area of an earthquake, then the ground shaking will be more intense, all other things being equal,” study co-author Glenn Spinelli, a research scientist with the New Mexico Institute of Mining and Technology, told Postmedia News. “Therefore, if the rupture area of a Cascadia subduction zone earthquake is closer to land, then the shaking on land will be greater.”

Mr. Spinelli — who published the study with former institute scientist Brian Cozzens, and recently completed a year of research with the Geological Survey of Canada in B.C. — noted that the goal of preparing for the next major Pacific quake is why U.S. and Canadian officials “have put considerable effort into estimating the potential … limit of seismicity for a potential large earthquake on the plate interface in the Cascadia subduction zone.”

He added that further research will be required to assess “just how much of a difference for potential ground shaking in Victoria, Vancouver, Seattle, etc., may result from an approximately 50-km landward shift” of the expected impact zone.

Prof. Goldfinger said in an interview that previous earthquake-hazard studies based on specific stretches of the Pacific Coast — such as parts of Washington state, where there have been long intervals between major quakes — have led some researchers to “downplay the hazard unknowingly,” pegging the likelihood of a disastrous event at only 10 to 15% within the next 50 years.

He said his team’s findings place that risk at up to 37% in some of the most vulnerable areas, such as parts of southern Oregon.

“At 10% or 15% [risk], earthquakes kind of fall into the category of potholes and repairing bridges and other things that need to be done over time,” said Mr. Goldfinger. “But if the real probability is something more like 30 to 40%, then this may happen long before we even start preparing for it.”

A Canadian earthquake-hazard study published in 2010 in the Geological Society of America Bulletin also concluded that the risk of a megathrust event in southern Cascadia was about twice as high as that in the northern part of the zone.

But even if the epicentre of the next monster quake were off the coast of California, GSC researcher Lucinda Leonard told Postmedia News at the time that the wall of sea water triggered by the event could well reach Canada.

“It’s fair to say that the probability of a major subduction earthquake is higher in the southern area, but we cannot be complacent in the north,” she said following the publication of that study. “Even if the next one ruptures only the southern part of the margin, the resultant tsunami will likely be hazardous to the B.C. coast.”

Panels call for urgent legislation to prepare for huge quake

By YOSUKE AKAI/ Staff Writer

Saying Japan’s very survival is at stake, two advisory panels urged the government to take immediate action--including finding an alternative capital--to prepare for an earthquake that could devastate the Tokyo area.

The working groups are discussing measures to deal with massive quakes that could be triggered by movement along the Nankai Trough as well as one directly under the capital.

In an unusual move, the groups called on the government to pass legislation for the quake-preparedness measures even before estimating the number of fatalities and damage from such temblors.

"There is a need for the entire society to deal with the two quakes that are expected to cause extensive damage," according to interim reports released on July 19 by the two working groups, respectively.

Passage of special measures laws would allow a wide area covered by the studies to take effective measures to deal with the possibility of the huge earthquakes.

The Nankai Trough extends from Suruga Bay near Shizuoka Prefecture to off the coast of Kyushu in southern Japan.

Special measures laws were passed in 1978 to deal with a possible Tokai quake and in 2002 to prepare for Tonankai and Nankai quakes. But there is no law for a unified response to a Nankai Trough quake with an expected magnitude over 9.0.

One estimate for possible damage from a Nankai Trough quake was 400,000 fatalities.

The two working groups have yet to come up with their own damage estimates. But their recommendation for swift passage of legislation underscores their sense of urgency from not being able to pinpoint when such a destructive quake might hit.

In preparing for a crippling quake directly under Tokyo, the interim report proposes selecting beforehand alternative sites that could provide back-up for capital functions. Among the cities named as possible alternative capitals were Sapporo, Sendai, Nagoya, Osaka and Fukuoka.

The interim report also called for measures to deal with long-period seismic ground movements and the huge number of people who will likely be stranded in Tokyo after a major quake.

It urged the government to secure revenues for the necessary measures, but it did not specify a figure. In the current fiscal year, about 480 billion yen ($6.1 billion) has been set aside for such measures.

The working group looking at a possible Nankai Trough quake is expected to release its estimates for fatalities and injuries as well as structural damage in late August. However, the group dealing with the quake expected to hit directly under Tokyo has not reached the stage of presenting specific estimates.

The interim report, warning that a Nankai Trough quake could trigger a tsunami 20 to 30 meters high, called on areas with indented coastlines to construct levees and move schools and social welfare facilities to higher ground. It also suggested building those structures to greater heights.

In addition, the reports said construction of straight evacuation routes on flatter areas are needed, as well as measures to make evacuations using cars more efficient.

Radioactive waste at Fukushima threatens second nuclear catastrophe

By Hiroko Tabuchi, Matthew Wald.

TOKYO: What passes for normal at the Fukushima Daiichi nuclear plant today would have caused shudders among even the most sanguine of experts before an earthquake and tsunami set off the world's second most serious nuclear crisis after Chernobyl.

Fourteen months after the accident, a pool brimming with used fuel rods and filled with vast quantities of radioactive caesium still sits on the top floor of a heavily damaged building, covered only with plastic.

The public's fears about the pool have grown in recent months as some scientists have warned that it has the most potential for setting off a new catastrophe. The three nuclear reactors that suffered meltdowns are in a more stable state, but frequent quakes continue to rattle the region.

The worries gained new traction in recent days after the operator of the plant, Tokyo Electric Power Co., or TEPCO, said it had found a slight bulge in one of the walls of the reactor building, stoking fears over the building's safety.

To try to quell such worries, the government sent the Environment and Nuclear Minister to the plant on Saturday, where he climbed a makeshift staircase in protective garb to look at the structure supporting the pool, which he said appeared sound. The minister, Goshi Hosono, added that although the government accepted TEPCO's assurances that reinforcement work had shored up the building, it had ordered further studies because of the bulge.

Some outside experts have also worked to allay fears, saying that the fuel in the pool is now so old that it cannot generate enough heat to start the kind of accident that would allow radioactive material to escape.

But many Japanese have scoffed at those assurances and point out that even if the building is able to withstand further quakes, a claim that they question, the jury-rigged cooling system for the pool has already malfunctioned several times, including a 24-hour failure in April. Had the failures continued, they would have left the rods at risk of dangerous overheating.

Government critics are especially concerned, since TEPCO has said the soonest it could begin emptying the pool is late next year, dashing hopes for earlier action. ''The No. 4 reactor is visibly damaged and in a fragile state, down to the floor that holds the spent fuel pool,'' said Hiroaki Koide, an assistant professor at Kyoto University's research reactor institute and one of the experts raising concerns. ''Any radioactive release could be huge and go directly into the environment.''

The fears over the pool at reactor No. 4, amplified over the web, are helping to undermine assurances by TEPCO and the Japanese government that the Fukushima plant has been brought to a stable condition and are highlighting how complicated the clean-up of the site, expected to take decades, will be. The concerns are also raising questions about whether Japan's all-out effort to convince its citizens that nuclear power is safe kept the authorities from exploring other - and some say safer - options for storing used fuel rods.

''It was taboo to raise questions about the spent fuel that was piling up,'' said Hideo Kimura, who worked as a nuclear fuel engineer at the Fukushima Daiichi plant in the 1990s. ''But it was clear that there was nowhere for the spent fuel to go.''

The worst-case situations for reactor No. 4 would be for the pool to run dry if there is another problem with the cooling system and the rods catch fire, releasing enormous amounts of radioactive material, or that fission restarts if the metal panels that separate the rods are knocked over in a quake. That would be especially bad because the pools, unlike reactors, lack containment vessels to hold in radioactive material.

Attention has focused on No. 4's spent fuel pool because of the large number of assemblies filled with rods that are stored at the reactor building.

According to TEPCO, the pool at the No. 4 reactor, which was not operating at the time of the accident, holds 1331 spent fuel assemblies, which each contain dozens of rods.

Professor Koide and others warn that TEPCO must move more quickly to transfer the fuel rods to a safer location. But such transfers have been greatly complicated by the accident. Ordinarily the rods are lifted by cranes, but at Fukushima those cranes collapsed during the series of disasters that started with the earthquake and included explosions that destroyed portions of several reactor buildings.

TEPCO has said it will build a separate structure next to reactor No. 4 to support a new crane. But under the plan, released last month, the fuel removal will begin late next year.