BU earthquake expert says that safer infrastructure can help
prevent catastrophic destruction and quake-safe reconstruction
could save lives in the future. Around 4 am local time on Monday,
February 6, two tectonic plates slipped past each other just 12
miles below southern Turkey and northern Syria, causing a 7.8
magnitude earthquake. It was the largest earthquake to hit
Turkey in over 80 years. Then, just nine hours later,
a second quake—registered at 7.5 magnitude—struck the same region.
The double whammy of intense shaking collapsed thousands
of buildings and killed over 20,000 people, leaving behind
a humanitarian crisis in an already vulnerable area. The
epicenter of the quakes was near the city of Gaziantep, where
there are currently hundreds of thousands of Syrian refugees.
Aleppo, a city in Syria that has been destroyed by civil war,
also felt the brunt of the earthquakes.
Seismologists consider Turkey a tectonically active area, where
three tectonic plates—the Anatolia, Arabia, and Africa
plates—touch and interact with each other. The two major
fault lines surrounding it, the North Anatolian Fault and the
East Anatolian Fault—which has a slip rate of between 6 and 10
millimeters per year—are gradually squeezing the country
westward toward the Mediterranean Sea. Yet, many buildings in
the region are not built to withstand large earthquakes,
according to the US Geological Survey (USGS), making the
Two major faults, the North Anatolian Fault and the East
Anatolian Fault, are gradually squeezing Turkey westward
toward the Mediterranean Sea, putting the region at risk
for earthquakes. Courtesy of Mike Norton, Wikimedia Commons
Why were the two earthquakes so catastrophic? To put their
cascading devastation into context, The Brink spoke with
Abercrombie about why the region is at high risk for earthquakes
and what can be done to warn people about an impending shake
before it’s too late.
How do you study earthquakes?
Some scientists go out and measure how much it [a fault] slipped.
People like myself are using the seismic waves and their
frequency content, because the frequency spectrum contains
information about the area of fault that slipped. I’m really
interested in what controls an earthquake. We know earthquakes
happen mostly on the faults. But there could be a big fault that
doesn’t seem to do anything for hundreds or thousands of years.
Then suddenly, within seconds, a crack bigger than you can believe
moves at speeds of kilometers a second. How do you go from one
thing to the other?
To understand the earthquake hazard around here, for example,
we have to look at earthquakes that happen elsewhere. Can we
take these earthquakes in Syria and Turkey and try to understand
what might happen if we had a similar-sized earthquake, which
we will, in California? I’m looking to understand how the seismic
waves propagate through the Earth, how much energy stays in them
as they travel, which is different in different parts of the Earth
because the rocks are different. The earthquake itself may be different too.
Once a place has a big earthquake, does that make it more likely to happen again?
That’s something we would like to know. In the short term,
we think it’s less likely. It’s hard to imagine how you
could have a magnitude 7.8 on that piece of fault again,
because there has to be a buildup [of stress] on the tectonic
plates for the plates to move. Since they’re only moving
at a few centimeters a year, it takes a while for that to
happen. For some bizarre reason, if there’s still some slip
waiting to happen while everything’s already shaking up,
another big earthquake could happen, but usually that doesn’t happen.
What improvements would you like to see as far as how earthquakes are handled?
We’d obviously love to be able to predict earthquakes.
As I said, I’m a bit skeptical because you’d still be
left with the destruction. Currently, earthquake scientists
are working to better their hazard forecasting to prepare
people for earthquakes. There’s also lots of work being
done in laboratories. Another area of research is improving
hazard maps to make them more dynamic, but that is more for
the long term so we can see changes with time. At the opposite
end of the scale, is earthquake early warning. It’s working
in California, Oregon, and Washington, and various other parts
of the world. Anyone can get an app on their phone so when an
earthquake happens, and the seismometers start to move, they
get an alert at speeds faster than the seismic waves travel.
This can be very useful to massively minimize damages—it
enables emergency services to be prepared and people can
turn off their gas tanks, turn off the water, and “drop,
cover and hold.” The BART [transit system] in Northern
California is using that, so as soon as they get an alert,
all the trains stop.
Provided by the IKCEST Disaster Risk Reduction Knowledge Service System