Earthquake Damage: Are Bad Maps to Blame?

A new study argues that earthquake-hazard maps didn't give engineers and seismologists a full picture of several recent quakes' dangers

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YOMIURI SHIMBUN / AFP / Getty Images

The badly damaged Japanese town of Yamada on March 12, 2011, a day after a massive 9.0-magnitude quake and tsunami hit the Tohoku region

Everyone makes mistakes — and sometimes, those mistakes can be deadly. Flawed hazard maps may be partly blamed for the devastation that accompanied the devastating earthquakes that have struck Japan, Haiti and China in recent years, according to a new study published in the journal Tectonophysics.

Hazard maps are guides to estimate how bad the earthquake danger is in any given area, and seismologists and engineers use them to gauge earthquake risk. But the maps can be oversimplified, largely because the mapmakers don’t have enough data about earthquake history in their areas of interest. As such, the study says, they often work off their own preconceptions — and the maps don’t do too well when those assumptions are wrong.

(PHOTOS: Japan One Year Later: Photographs by James Nachtwey)

“We’re playing a complicated game against nature,” study co-author and earth-and-planetary-sciences professor Seth Stein said. “It’s a very high-stakes game.”

The study looked at three of the biggest earthquakes in the past five years, and whether the damage had been accurately predicted by the hazard maps:

Japan
The Tohoku earthquake of 2011 released 150 times more energy than hazard maps predicted. The maps estimated that an earthquake in the area would probably reach 7.5 on the Richter scale and that the Tohoku area was a lower-risk region than other parts of Japan. That March, the 9.0-magnitude earthquake that ravaged the area left tens of thousands dead, obliterated buildings and led to a meltdown at the Fukushima nuclear power plant.

Haiti
In 2001, hazard maps predicted low ground motion in Haiti based on recent earthquake data for the region. Had the maps taken a longer-term view of earthquake history, they would have shown that over history Haitian earthquakes are generally more damaging, and the 7.1-magnitude earthquake that ravaged Port-au-Prince in 2010 might have been a little more manageable.

China
Mapmakers assessed the Longmenshan fault as low risk, but they may not have considered the gradual movement across the fault that would eventually build enough tectonic pressure to cause a 7.9-magnitude earthquake in Sichuan province. This mistake came from a lack of evidence for large earthquakes on the fault over the past thousand years, according to the study.

The researchers who conducted the Tectonophysics study propose two changes to current mapping approaches: communicating the uncertainties of each map to users and checking each map against a reference map. Perhaps most important, however, is the authors’ recommendation that mapmakers approach their jobs with a “sense of humility and caution.” Nature is full of exceptions and surprises, and even the best hazard maps can’t stop the planet from breaking the rules sometimes.

Thean is a contributor at TIME. Find her on Twitter at @tarathean. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.

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32 comments
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swathesbalakrishna k
swathesbalakrishna k

Our present achievement itself a testimony for our past mistake on which we achieved strength of imagination to conquer any situation on our living place .

Only after seeing alone one can tackle and over come and not otherwise. 

Will Taggart
Will Taggart

Even a 3-year-old can probably figure out the mapmakers are coerced by local government to minimize the map projections and data in a pathetic bid to keep the public as dis-informed as possible about the realistic effects of earthquakes. If they were to actually provide the truth, then they might have to spend billions of their stolen money on preventative and safety mechanisms. They know it's much better for them to lie to the people, and have others lie for them, in order to keep their personal apple-carts as stable and as full as always. Criminals are not stupid, but the common people absolutely are, so they will always take full advantage of that difference.

Yves Konigshofer
Yves Konigshofer

If the maps understate the risk for a major earthquake (or other hazard), more people will likely die during one.  If the maps overstate the risk, people may end up paying far too much for construction, insurance, etc. in preparation for an event that is unlikely to happen in their lifetime.  However, even accurate maps are of little use if people choose to ignore them.  Just look at cities like San Francisco where many live in homes that should be retrofitted and where many do not have earthquake insurance.

man4earth
man4earth

Real-time earthquake maps from the USGS are not showing all earthquakes, for example in the last two or three weeks there have been three quakes at the mouth of Mobile Bay Alabama showing on the Earthscope ANF website but not on the USGS site. A couple of weeks ago there was a quake reported by WLOS 13 news in Asheville North Carolina, they contacted PARI where the spokesman said it did not register on the Richter scale, that quake was not displayed on USGS real-time maps until 24 hours later, it was somewhere around a 2.0, and never was displayed on the Earthscope site. There are many other examples.

The point is, if data is used from only one of these sites it will not provide adequate information for good decision making.

Vincent Wolf
Vincent Wolf

If you want to see the worst flawed map in existence it's the one produced by the USGS for Southern California.  Totally unrealistic maximum 7.5 scenario's will be updated soon with 8.5+ shockers--similar to the recent pair of 8.2 and 8.6 shockers in the Sumatra area that too were strike-slip faults that the USGS said could NEVER produce a quake that large.

Recent research by several California Universities are beginning to show that the periods of quakes have been substantially down played by the USGS as well. Their research says an 88 year period on Fort Tejon and Wrightwood but the USGS keeps saying it's 250 years. Total BS.

Lives are at stake here.

The USGS has been underplaying the risks for over 40 years to protect it's own property values and cater to the whims of rich real estate agents.

caveman664
caveman664

Hello Vincent, It would be nice to see where your information might be posted online.  Which CA universities do you refer?  If California is subject to an 88 year major earthquake cycle,  they have apparently must have missed the  last two or three cycles (They were first settled in 1780-ish)? Finally, which property values to which you refer.  I'm not too sure the USGS owns much land.   

IDontThinkSo2
IDontThinkSo2

Gee, you wouldn't think predicting the future would be that hard.

LoudRambler
LoudRambler

 You can - to a degree.

 The point about Tohou earthquake specifically is that in the aftermath the area was - obviously - studied to death, and it was uncovered that Tohou came from a previously unknown crack in the fault line.

 Japanese may have a little bit spotty history on graft and corruption, but they have stellar track record when it comes to competence and thoroughness, so it boils down that often things you didn't know about will blow in your face very badly without no person to blame and no way of stopping it before the fact.

ozonator
ozonator

“Real seismologists insist that predicting earthquakes is impossible” (“Italy Earthquake: Are Scientists Really Responsible for Deaths?”; uk.ibtimes.com, 9/20/11).

Kristen R Turner
Kristen R Turner

However, even accurate maps are of little use if people choose to ignore them.  Just look at cities like San Francisco where many live in homes that should be retrofitted and where many do not have earthquake insurance. http://Unlimitedjoys.blogspot....

ozonator
ozonator

The USGS is currently making it's ok earthquake reports corresponding to regions, geological features, and significant geopolitical units into meaningless drivel corresponding to the nearest obscure village (earthquake.usgs.gov).  So yes, bad maps are to blame. In fairness, at least 1/3 of all geologists are wretched humans, 1/3 are saints, and none with ever get a Nobel Prize for science.

nullhogarth
nullhogarth

Apparently Time.com doesn't use editors, or bother to read their copy before publishing it.  Please have a look at the first two paragraphs of the article for examples that led to my drawing this conclusion.

Phoenix31756
Phoenix31756

Map reading by the so-called wizards don't do no good!

Just ask those engineers who allowed Nuclear Reactors too being built on fault lines, like in California ! 

Gary McCray
Gary McCray

The maps were all seemingly based almost entirely on recent historic local data.

Science can actually do a much bigger job of calculating new events than these maps seem to have depicted.

Also, politicians like to downplay anything potentially problematic, my guess is the maps were also watered down in response to external pressure.

Funny, real earthquakes don't much care what politicians think or well tolerate inadequately thought out predictions.

In the end, they simply are what they are.

s0cialseven
s0cialseven

willie wonka kidnapped me and molested me.

RobertSF
RobertSF

Maybe bad maps are the problem in Japan, but in places like Haiti or the Middle East, it's just shoddy construction practices. Earthquakes in the 5.0-6.0 range aren't supposed to level towns like they do in Turkey, Iran, etc. if reinforced steel is used properly.