All language subtitles for S38E08 - Deadliest Earthquakes

In 2010, massive earthquakes rattle the
globe.

In Haiti, over 200 ,000 people are
killed.

Weeks later, cities half a world away in
Chile are leveled.

Half a million buildings damaged.

Around the globe, millions live above
active earthquake zones.

What caused these earthquakes?

And why are the subterranean tremors so
hard to predict?

We can't see earthquakes coming. That's
the problem. One minute, they're not

there. The next minute, wham.

Now, the race is on to find ways to warn
us of impending disaster.

And science is revealing new insights
into what is actually going on.

Beneath the surface.

It tells us something about the way
plates glide past each other that we had

clue about before.

But the clock is ticking.

And the next one could be in our own
backyard.

This is earthquake country. We don't
know when that earthquake or sequence of

earthquakes will occur, but they're
inevitable.

The earth -shattering truth behind the
deadliest earthquake.

Up next on NOVA.

and Discovering New Knowledge HHMI

and by the Corporation for Public
Broadcasting

and by contributions to your PBS station
from viewers like you. Thank you.

Port -au -Prince, Haiti.

January 12, 2010.

4 .53 p .m.

The city is hit by the western
hemisphere's deadliest earthquake in a

This busy metropolis is reduced to
rubble in less than a minute.

233 ,000 people lie dead.

Millions more are injured.

Or orphaned.

As 2010 unfolds,

more earthquakes strike around the
world.

Each time there is no warning and often
massive loss of life.

Scientists are working around the clock
to unlock the mystery of earthquake

prediction.

Within days of the Haiti catastrophe,
Professor Eric Calais, a seismologist

Purdue University, arrives on the
island.

Calais and his colleagues are at the
cutting edge of earthquake research.

They could see this disaster coming.

They'd known for years that a Haitian
earthquake was inevitable.

Today, Calais is leading a rapid
response mission to find out exactly

happened and to assess the risk of more
quakes.

For nearly a decade, he's used GPS
markers scattered throughout Haiti to

the ground shifting under the island.

We're headed to a place where we have
what we call a benchmark.

We have a precise position for that
benchmark before the earthquake, and now

we're going to measure its position
after the earthquake.

Many markers are placed in well -built
police stations.

Embedded in solid concrete roofs, they
survive the earthquake.

The benchmark that we're talking about
is not spectacular at all. It's a piece

of metal, stainless steel.

that we sealed at the top of this
building.

And there's a little dimple that's about
a millimeter wide.

And this is the point we've been
tracking over time. Since 2003, the

we measured this point.

Calais' GPS measurements reveal telltale
movements of the Earth.

Over a decade, The satellites track the

ground south of Port -au -Prince,
creeping east, and the ground north of

city, creeping west, at fractions of an
inch a year.

Then, during the quake, a huge slippage
takes place.

This location here moved by about 30
centimeters during the earthquake.

This is 30 centimeters, more or less,
something like that. So this whole area

here has moved 30 centimeters to the
east during that earthquake.

These movements are a clue to what
happened underground.

The earth ruptured nearly a foot along a
hidden fault line.

Most earthquakes originate in deep
fractures in the crust, miles beneath

surface.

These giant fractures crisscross the
globe, splitting the planet's 50 -mile

thick crust into around a dozen huge
rocky slabs.

The Earth is enclosed in a rigid shell,
if you like, and this shell is made up

of different plates, rigid rocky plates,
which move around at about the same

speed as your fingernails grow.

There's this sort of dance of the plates
going on all the time around the

planet's surface.

Geologists call this dance plate
tectonics.

The planet's internal heat moves the
huge plate.

Above the hottest zone, molten rock
rises and solidifies, creating new

crust.

The new crust jostles for space, forcing
crust on cooler edges to grind against

other plates.

or push beneath them.

But wherever or however plates collide,
they generate earthquake.

Earthquakes happen because these huge
chunks of rock that form the earth's

don't slide against one another nice and
smoothly.

They stick and they lock.

So you're getting this enormous
accumulation of strain and then you're

it released in a matter of seconds
during the earthquake.

The quakes can originate tens of miles
down, but the energy they generate

creates deadly vibrations on the
surface.

The amount of energy generated in the
biggest earthquakes are comparable to

many, many thousands of nuclear bombs
going off. There's a huge amount of

energy, absolutely vast.

Haiti lies directly above a network of
massive faults, where the Caribbean

meets the North American plate.

As the plates slowly creep past one
another, the rock distorts and stretches

like rubber, building up enormous
stress.

Since 2003, Calais and his colleagues
used ground movement data to calculate

stress levels at the plate boundaries.

Calais realized a deadly quake was
inevitable.

What we saw was a fault being loaded
just like a rubber band.

Simple math allowed him to calculate the
precise elastic strain on the fault.

The last earthquake on that fault
occurred about 250 years ago.

And it's building up elastic energy at 7
millimeters per year.

7 times 250 is about 1 .8 meters.

That's almost 6 feet of stored strain,
equivalent to 100 Hiroshima atom bombs.

Seismologists use a logarithmic scale to
measure earthquake strength.

Each number indicates a seismic wave ten
times larger than the number below.

A two is insignificant, but a seven or
above can be immensely destructive.

In 2008, Calais announced the Haitian
fault could generate an earthquake above

magnitude seven.

Two years later, His forecast proves
accurate.

Breaking news from Haiti tonight where a
massive 7 .0 earthquake struck... A

major earthquake measured at 7 .0.
History has crippled the country

.0. Calais came closer than anyone to
giving an accurate warning of the quake.

But like all seismologists, he had no
idea exactly when it would happen.

We cannot predict earthquakes.

We had no way of telling...

whether it was going to be today,
tomorrow, in 10 years, in 100 years. So

didn't put a date on it. And it's not
that we were afraid to put a date on it.

As a scientist, we can't.

Today, seismologists can calculate the
pressures on the plate boundaries.

But they can't predict when the fault
will rupture.

We can't see earthquakes coming. That's
the problem.

One minute, they're not there. The next
minute, wham.

Back in the lab, Calais now attempts to
find out how much stress remains in the

Haiti Fault.

It's bad news.

We saw on January 12th that only a small
portion of the fault actually ruptured.

The fault itself, from the Dominican
Republic all the way to the western end

the southern peninsula of Haiti, is
about 300 kilometers long.

And it's only a segment of 50 kilometers
in the middle that released.

its energy during the earthquake.

The rest of the fault remains under
stress.

Calais predicts that segments even
closer to Port -au -Prince could snap at

time.

Those segments have been brought
slightly closer to the next earthquake.

Again, what's the timeline?

We don't know.

Port -au -Prince is not alone in its
predicament.

Anywhere on the globe above an active
fault is vulnerable.

And the faster the underlying plates
move, the more frequent the quake. The

Middle East, South Asia, China, the
Pacific Rim.

In the absence of prediction, these
zones remain some of the world's

places.

And let's not forget California, home to
the San Andreas Fault.

This infamous fault system stretches 800
miles from Northern California

to the Mexican border.

Like the fracture under Haiti, it's a
vertical strike -split fault, meaning

plates grind past one another
horizontally.

But here, the plates move more than
three times faster at over an inch a

generating powerful earthquakes.

In the south, some sections have been
quiet for over 150 years.

Now, satellites measuring ground shift
reveal a buildup of stress energy

equivalent to 3 ,000 nuclear bombs.

The next rupture could be the big one.

And it's the L .A. region that's under
threat.

Tom Jordan of the Southern California
Earthquake Center has spent years

preparing for this quake.

We have something like 800 scientists
working together on a series of projects

trying to really understand the
earthquakes in Southern California,

have a very complex fault system, very
active, a lot of risk to the 20 million

people that live here.

This is earthquake country.

We don't know when that earthquake or
sequence of earthquakes will occur, but

they're inevitable.

The last lethal quake on the San Andreas
Fault system was the 1994 Northridge

earthquake, which killed over 60 people
and caused $20 billion of

damage.

And that was only a magnitude 6 .7.

Jordan and his team believe that levels
of stress now indicate the rupture on

the main fault could be 30 times
greater.

The city recently played out a worst
-case scenario.

We had an exercise that we developed for
Southern California in 2008.

We call it the Great Southern California
Shakeout.

We created a scenario of a very large
earthquake, magnitude 7 .8 earthquake,

the San Andreas Fault just east of Los
Angeles.

And we asked the question, what would
happen if that earthquake occurred?

The conclusions?

Over $200 billion of damage, millions of
people displaced, and thousands of

dead.

If this earthquake would have happened
in reality, there would have been

buildings coming down. We know that
there would be no water now in certain

areas. That's what this exercise is all
about.

If scientists are right, millions of
people face a massive disaster.

The Fender asphalt is very capable.

You might say it's locked and loaded.

With so much at stake, some
seismologists are exploring new methods

forecasting when a quake will happen.

Probing deep inside the hazardous
faults, they're learning to listen for

Anza Borrego State Park, Southern
California.

This rig is drilling for something more
precious than gas or oil.

It's part of an ambitious attempt to
find the holy grail of seismology.

Underground activity that could warn of
the next major earthquake.

Geologist Frank Vernon is in charge.

So this is your third drill string here?

Third stick. Third stick going in?

They're just a few hundred feet from the
San Jacinto Fault, an active offshoot

of the San Andreas system.

We actually have a lot of earthquakes
occurring in here. As I said, we've had

four magnitude fives in the past decade.
We have magnitude fours on the average

about once a year.

Four days ago we had a magnitude 5 .6 10
kilometers over here It's a very unique

place. So this is the reason why we want
to work here

The team

uses the rig to plant sensors deep into
the rock Embedding them 800 feet

down shielded from surface noise here As
clashing plates squeeze

and distort along the fault line, tiny
tremors and pressure changes are

produced.

The sensors detect them.

Any one of these signals could be the
clue that a major quake is imminent.

You're measuring the change in shape of
the Earth right underneath us in these

boreholes. When an earthquake happens,
you will see a change in that shape.

There will be slight changes that we can
observe.

But identifying a specific tremor or
pressure change that always precedes a

major quake hasn't been easy.

Over the last four years Vernon's team
has surrounded the fault with eight

borehole sensor stations.

They've recorded many small earthquakes
and are now sifting through a huge

amount of data.

The race is on to find a signal that is
common to all of them.

We're a long way from real earthquake
prediction.

It's not like we're going to achieve it
today or tomorrow.

That's quite a bit further down the
road.

Though they haven't found it yet, this
method of forecasting earthquakes holds

promise for the future.

But for now, the earthquakes keep on
coming.

Just weeks after Haiti, another massive
quake.

Chile, South America.

February 27th, 2010.

Three in the morning.

This quake reaches an incredible
magnitude 8 .8, the fifth largest ever

recorded.

Daybreak revealed the scale of the
damage.

Half a million homes damaged or
destroyed, and hundreds dead.

The quake is so violent, it accelerates
the Earth's rotation, knocking a

millionth of a second off the length of
the day.

It's nearly 500 times larger than the
Haitian tremor.

So why is this quake so powerful?

Soon after the disaster, geologist Mike
Beavis arrives in Chile to find answers.

This place repeatedly has...

huge earthquakes right now the number
one and the number five earthquakes of

recorded you know history are right here
so that makes this the world champion

place for big earthquakes all of chile's
strong quakes originate off its pacific

coast so that's where buddha is looking
for evidence the island of santa

maria sits just 60 miles east of the
boundary of the south american plate and

the nazca plate This falls under the
Pacific Ocean triggers the enormous

This beach is one of the closest points
to the offshore epicenter.

At the base of the cliff, Beavis notices
a white spree, a clue to the quake's

sheer power.

All right, so here we are looking at
this big rock. It's in situ.

It's got all of this white concretion,
which is something that forms under the

sea. It's got seaweed and there are
actually limpets and muscles and things

attached to the rock. I can see some
right up there, more than four feet

my head.

What this is telling you is that the
whole coastline jumped up two to three

meters.

There's two minutes the ground shaking
like crazy and during that two minutes,

this whole coastline lifted up.

And all these marine creatures are now
stranded in the air.

The eight feet of uplift happens because
the plates here are not grinding past

one another side by side, like the
faults under Haiti and California.

They are subducting, one pushing beneath
the other.

When the fault ruptures, the overriding
plate punches upwards, creating an

extremely powerful quake.

When you're getting subduction, the
overriding plate is actually being

the plate that's being pushed down. And
that, over time, accumulates a massive

amount of energy.

The enormous areas of plate that shift,
and the huge uplift produced,

give these epic quakes their name.

Megathrust.

And they have a chilling side effect.

Tsunami. The uplift raises the sea
above, creating a wave.

It travels across the ocean at over 500
miles per hour, wreaking havoc.

In 2004, a 9 .3 megathrust.

150 miles offshore leads to the infamous
indian ocean tsunami that kills almost

a quarter of a million people

in

2010 the chile quake generates its own
tsunami engulfing coastal villages

like dichotto

The wave destroys over 90 % of the town.

Mike Beavis and geophysicist Frederick
Bloom survey the aftermath.

Oh my goodness, there's a... looks like
a child's sock hanging up 20 feet above

our heads.

Yeah.

I think that sock is probably the high
water mark.

Oh, that's...

Easily 30 feet above sea level.

Easily 30 feet. Yeah. My goodness.

Nobody stood a chance here.

When the leading edge of a tsunami hits
a shallow shoreline, it slows down.

But as the faster water behind backs up,
the wave swells.

Here in Dechato, the wave reaches the
upper floors of buildings.

Looks like the water took out the
drywall about halfway up the second

Yeah, about one time.

It wastes damage everywhere.

Look at this. Fish on the floor.

My goodness.

Lots of fish.

You're next to the fish. No olvides.
Don't forget.

Today, I will be thinking of you. Happy
Valentine's Day.

Wow.

I hope these people knew what to do when
it happened.

The wave's height explains its
destructive power.

A 30 -foot wave exerts a pressure
equivalent to the weight of a battle

As it flows in and out, it scours the
earth, destroying foundations and

undermining buildings.

Well, when I was a surfer, they used to
tell us that one cubic meter of water

weighed about a ton. You know, if you've
got a 30 -foot wave, there's an awful

lot of force.

It's like a wall of water that comes in
and never goes away. So the currents are

just pushing and pushing and pushing for
minutes in the same direction and just

rip everything apart.

It just doesn't stop coming.

Predicting and forecasting megathrusts
is critical for North America.

The Aleutian Fault causes many quakes
along Alaska's coast.

And in the 1980s, seismologists realized
the Cascadia Fault that lies off of

Oregon and Washington is also active and
can generate powerful megathrusts.

The cities of Portland, Seattle, and
Vancouver

are all at risk from a quake that could
strike above magnitude 8.

Forecasting the likelihood of the next
Cascadia quake is vital.

On land, evidence is hard to find.

But offshore, the answer is being
discovered, buried in the mud.

a cold storage room at Oregon State
University.

Here, hovering a few degrees above
freezing, are tubes containing clues to

the quakes that have hit this region in
the past few thousand years.

They're the prized possession of
Professor Chris Goldfinger.

These are essentially a deep -sea
library. These are core samples

in oceanographic expeditions over the
last 50 years or so.

So these core samples can show us things
about paleoclimate and, in my case,

earthquakes.

Goldfinger spent the last decade
collecting these cores directly from the

Cascadia subduction fault off the coast,
punching deep into the sea floor and

extracting columns of sediment.

But each core tells an earthquake story.

They're formed from layers of sandy
deposits laid down over huge periods of

time.

Thousands of years of history are
contained in a few yards of mud.

They're essentially a tape recorder,
just like a sound tape recorder records

everything that happens in a room. These
cores record everything that happens to

the sea floor over time.

To help forecast the next Cascadia
quake, he needs to know how often they

in the pack.

Undersea earthworms create huge
landslides that coat the sea floor.

They deposit distinct identifiable sandy
layers.

This is a sandy layer left by a
megathrust landslide.

You can see that at the base of this
Sand layer, there's a very sharp base.

This is one telltale sign of a type of
deposition that happens just after an

earthquake.

But to distinguish one earthquake from
another, Goldfinger must probe deeper

into each sample.

Using the CT scanner really
revolutionizes how we can look inside

Each one of them seems to have a special
character, a unique fingerprint.

We can compare those from one place to
another and use that to trace the

earthquakes along the length of the
seduction zone.

Before this study, only 19 earthquakes
in 10 ,000 years were identified in this

region.

Based on that, the odds of a quake
happening here over the next 50 years,

estimated to be at most 1 in 7.

But Goldfinger's CT analysis of the core
sample identifies over 20 previously

unknown quakes.

Hearts of Cascadia are twice as active
as previously thought.

This means the chance of a megathrust
isn't 1 in 7, it's 1 in 3.

This isn't just a remote possibility,
this is a likely possibility.

Those numbers mean that chances are
actually pretty good that it's going to

happen in our lifetime, that it will
actually happen in the next 50 years.

A megathrust quake along the Cascadia
Fault would also generate a deadly

tsunami.

In the front line are towns on the
Oregon coast.

like Cannon Beach.

When the earthquake hits, this town will
not only suffer intense shaking, but

the power of the deadly wave.

Yumei Wang knows the challenge the
community faces.

The Cascadia earthquake and tsunami will
definitely occur.

The question is when.

Cannon Beach will be devastated.

We're going to have several minutes of
strong ground shaking and then about 20

minutes before the tsunami starts
rolling into town.

If a tsunami was on its way right now
and I was standing right here, I would

die.

The velocities would be tremendous. You
wouldn't be able to outrun it.

The tsunami can look like a breaking
wave, but rather than receding back, it

would just keep rushing in.

The people of Cascadia face a deadly
double hit, but there may be hope.

A hundred miles north of Cannon Beach,
scientists are finding traces of a new

type of super deep earthquake, one that
may help revolutionize earthquake

forecasting.

The Olympic Peninsula, Washington State.

These peaceful forests hide a secret.

Beneath, something is stirring.

Imperceptible to human senses, a silent
earthquake is taking place.

Every 14 months, tiny tremors vibrate
the ground for weeks at a time.

They're so quiet, no one knew they
existed.

But now, scientists are taking a closer
look, and what they see might be

the future of earthquake forecasting.

Should be around here somewhere.

I see it.

Ken Crager of the University of
Washington has spent years on the trail

silent quake.

His challenge is to find out what causes
them.

For years, the earthquake tremor signals
were hidden among vibrations generated

by machinery.

crashing waves, even the wind in the
trees.

These signals that we're seeing now,
which we now know as tremor, they've

going on forever, and we've viewed them
as noise in the past because we had no

idea what they were. As time goes on, we
often find that one person's noise is

another person's signal.

To isolate the signals, Krager uses
seismometers that can distinguish

deep tremors from weak, shallow tremors.

These are buried just about a foot or so
underground.

Make sure they're nice and quiet. But
the signals that we're trying to record

are about 40 kilometers, way down there.

Here we go.

A stomp test helps calibrate the
seismometer.

The signals we're actually looking to
try to get out of these are very much

quieter than the stomping I'm doing,
maybe a thousand times smaller, very,

subtle signals.

And there we go, three beautiful spikes.

Now, Krager's data reveals new insights
into how the plates move deep down.

Most earthquakes occur around 15 miles
down, where the plates are locked.

But around 25 miles down, there's a
hotter zone.

Here, the plates lock briefly.

Every few years, they slip.

with only a slight amount of shaking.

It's called slow slip, and it generates
the silent quake.

It was very exciting because it tells us
something about the way plates slide

past each other that we had no clue
about before.

Identifying slow slip tremors could be
critical in signaling larger quakes.

During a slow slip, the chance of a
major quake may double.

Every time the deep lake slips, stress
increases on the locked crust above.

Eventually, a slip could trigger a major
quake.

Detecting the onset of these silent
quakes could provide a warning that a

quake may be imminent.

I'm optimistic about the future. I think
that in principle, a slow slip may

precede big earthquakes.

And so it's possible that by
understanding slow slip better, we'll be

predict earthquakes in the future.

Slow slip research is in its infancy.

For now, seismologists must rely on
other factors.

to determine earthquake threat levels
earthquakes can be triggered by other

quakes energy released by one quake can
travel along

a fault causing it to unfasten like a
zipper what happens then is it transfers

strain onto the next bit and it brings
forward the time that that ruptures

generates another earthquake and then
that does the same to the next bit of

fault

This domino effect was recently observed
near the U .S.-Mexican border.

Mexicali, April 4th, 2010.

A magnitude 7 .2 quake strikes close to
this border town.

No one is killed, but over the following
month, it triggers a series of smaller

quakes spreading over the border.

Could the transferred stress eventually
trigger the big one in Southern

California?

I have a sense of foreboding right now.
We're a little bit nervous because that

could be foretelling the possibility of
a big rupture on one of the faults here

in Southern California.

You know, I think the chances of us
having a large earthquake are very

significant.

But could earthquake threat levels ever
rise globally?

Could the recent Haiti, Chile and Mexico
quakes all be related to a global

increase in seismic activity?

Over the last few years, the concept of
global clustering of earthquakes has

gained some ground.

Geologists have suggested that there is
this global clustering with maybe a

cycle of 50 years, and that it's related
in some way to stress changes in the

Earth's crust as a whole.

There may be some common phenomenon
occurring that's causing more

But there's no proof that global
clustering was a factor in 2010.

Seismic activity was within normal
levels.

The Haiti earthquake, magnitude 7, is
not particularly rare, and we might see

several, a dozen of those maybe a year.
The great earthquakes like Chile,

magnitude 8 and above, we see about one
of those a year.

2010 stands out because its earthquakes
killed nearly a quarter of a million

people.

When we get earthquakes that cause a lot
of damage, kill a lot of people, our

awareness of earthquakes rises, and
that's what we're seeing now.

It is nothing anomalous in terms of the
seismic activity.

This is the Earth doing its thing. This
is what we have to expect in terms of

large earthquakes.

The recent tragedies are a reminder that
despite almost a half century of

research, seismologists are no closer to
predicting earthquakes.

The task may be impossible.

Thirty, forty years ago, we were very
optimistic that earthquake prediction

kind of around the corner. We thought
there was a lot of new information and

understanding of the earthquake process
that would allow us to predict

earthquakes. Now, in fact, there are
some suggestions we may never be able to

predict earthquakes with high certainty.

Without high certainty, getting people
to take action is difficult.

For a prediction to be useful to any
degree at all, we have to be sure that

earthquake is going to happen. 50 % is
no good. You're not going to have to

evacuate a major city and involve
massive disruption of the population and

industry and commerce and everything
else on the idea that an earthquake has

50 % chance of happening.

If prediction is going to be useful, it
has to be 100 % certain.

But you don't always need to predict a
quake to sound the alarm.

Having even a few seconds to respond
could save lives.

And earthquakes make this possible by
generating their own warning signal.

Dr. Richard Allen works at the
University of California at Berkeley, a

built above the Haywood Fault in
Northern California.

This is an expansion joint in the
stadium, and you can see that it opened

a result of the continual motion on the
fault.

It comes right beneath the stand,
continues across the field, beneath the

post, and on across campus.

The Haywood fault runs parallel to the
San Andreas, on the other side of the

Francisco Bay.

Berkeley's location makes it a perfect
place for ShakeAlert.

America's first earthquake early warning
system.

Earthquakes generate different types of
seismic waves, radiating out faster than

speeding bullets.

Traveling at over 15 ,000 miles per
hour, the fastest are the primary, or P

waves, but they rarely cause more than a
jolt.

They're followed by the slower S waves
and surface waves.

These slower waves generate the large
ripples in the ground and cause most of

the damage.

That's where this crucial warning time
comes from, the difference between the P

wave and the S wave.

In a rupture on the San Andreas Fault,
the P wave would come rushing across the

Bay Area at about 7 kilometers per
second.

We can detect it, we can issue a warning
before the much slower S -wave

gradually comes across, does all of the
damage.

Providing adequate warning is a race
against time.

The P -wave must be detected and the
alert sounded in a split second before

destructive S -waves follow.

The tools for the job are kept
underground or buried deep in hillside

This

was built after the Second World War to
monitor nuclear tests now we use it for

our research

These

are the finest Swiss -made seismometers.

Their precision allows them to detect
very weak tremors, locating earthquakes

and estimating their magnitude with
extreme accuracy.

Alan and his team have connected over
400 seismometers in a huge network

California.

Buried beneath the soil, they wait for
the next quake.

Ready to sound the alarm the moment a P
wave is detected.

Each of these stations is sampling the
ground shaking at 100 samples per second

with huge volumes of data.

And by having very fast computers and
very efficient new algorithms, we can

process it all simultaneously within
just a fraction of a second.

The speed of an electronic warning
signal is much faster than the slower S

-waves, providing critical seconds to
prepare.

New wave warning systems already operate
in high earthquake risk countries like

Japan.

When detected, trains automatically
halt, gas mains seal, and alerts sound

many schools, businesses, and homes.

With ShakeAlert in place, Californians
will be able to take similar evasive

action.

I do not want to be surprised by the
next big earthquake.

Instead of being surprised by sudden
shaking, I want my phone to start

at me so I can get underneath the table.

Earthquake alert. Five seconds
remaining.

And I think that's very reasonable to
see that happening here in California in

the next five years or so.

But there are limits.

If a quake is hundreds of miles away,
ShakeAlert could provide up to two

warning. But the closer it is, the less
warning is possible.

P -wave warning systems help, but
they're not the answer.

If you're right on top of the earthquake
epicenter, if it's happening right

underneath you, then P -wave detectors
are of no use. The earthquake will hit

you before they can do anything at all.

Many scientists now believe the real
answer to the earthquake threat lies in

engineering, not geology.

In the January 2010 quake, the vast
majority of Haitians who die are killed

collapsing buildings.

As most seismologists will tell you,
it's buildings that kill people, not

earthquakes. If we construct it properly
in most areas of high seismic hazard,

then the death tolls would drop
dramatically.

The challenge for engineers is to design
buildings that can survive destructive

vertical and horizontal shaking.

Engineers now use enormous shake tables
to test new designs.

Their huge hydraulic pistons mimic
powerful tremors.

Results are helping revolutionize
building designs.

Damaging earthquake motion is minimized
using deformable or floating foundations

or offset by complex counterweight.

Skyscrapers are built with confidence in
some of the most earthquake -prone

regions on the planet.

In the U .S. and in most developed
countries, Construction in earthquake

is now controlled by building codes.

But in places like the Pacific Northwest
Coast, the engineering challenge is

greater.

Buildings here must also deal with
tsunamis.

Right down that coastline.

There is a problem with big waves coming
in after this earthquake and I'm not

convinced that the communities there are
prepared for that at all.

These images are from the 2004 Indian
Ocean tsunami.

There is nowhere to run.

The fast -flowing debris destroys one
building after another.

Residents along the Cascadia Fault in
the Pacific Northwest face the same

But one Oregon town is trying to change
all that.

The residents of Cannon Beach have a
unique plan to keep their heads above

water.

They're planning an extraordinary new
city hall.

What we're looking to do is to tear down
this building and replace it with a new

building that is both earthquake and
tsunami resistant.

This design is called a tsunami vertical
evacuation refuge, a survival platform

over 30 feet high with space for over 1
,000 people, most of the population.

Extensive testing recreates the impact
of intense shaking, waves, debris, and

scouring from the tsunami, ensuring the
structure can withstand punishment.

It can take very large forces, not just
water with sand, but also

parts of buildings and cars coming and
slamming into the building.

Tensioned steel cables hold it together.

and recenter it after the earthquake.

Reinforced concrete pillars allow water
and debris to flow through or minimize

impact with their rounded profile.

And extra deep foundations keep it
standing as surrounding soil washes

This building will remain intact.

It would be possibly the only building
left standing in this whole

What we have in mind is ideally to have
dozens of these up and down the

coastline so that all of the low -lying
communities with tsunami hazards have

these to protect their people.

These revolutionary designs may
transform many buildings along the coast

death traps to life -saving.

Over the last quarter century,
Seismologists have made huge strides in

understanding how and why earthquakes
happen, and calculating where, if not

when, they will strike.

The disasters of 2010 prove that
prediction remains tough.

But the knowledge engineers now gather
can make us safer.

I don't think we can ever expect to
conquer earthquakes in the sense that we

predict them to the day and we can cope
with them so that no lives are lost and

no buildings fall down.

We have to live with them. They're a
natural phenomena.

They've occurred throughout Earth
history. They're going to continue to

What is...

crucial is that we be able to live with
earthquakes and to sustain earthquake

damage in a way that we can bounce back.

We are looking to develop resilient
communities, communities that can deal

these effects in a smart way. We want to
keep disasters from turning into

catastrophes.

Surviving an earthquake comes down to
how well you prepare for the worst.

Until seismologists make a breakthrough
in prediction, communities must be ready

for the unexpected.

Because the next quake could strike at
any time.

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