Let’s learn about
earthquakes
How to defend yourself against earthquake disasters

An earthquake canstrike at any time,at any place.

Let’s learn about
earthquakes anddisaster prevention!

The Headquarters for
Earthquake Research Promotion

It’s an earthquake! What would you do if one happened?
Earthquakes can strike at any time, at any place.
Earthquakes are more frightening than anything. They strike suddenly, and it is difficult to exactly
know when and where they will strike. That’s why we need to understand earthquakes correctly
and acquire knowledge for coping with them.

AtschoolWhengoing toand fromschoolSchool buildings damaged by an earthquake:
The Great Hanshin-Awaji Earthquake Disaster, 1995

A concrete block wall collapsed by an earthquake:
Niigata Chuetsu Earthquake, 2004

*Photo provided by Kobe City

*Photo provided by Tohoku UniversityAthome
An earthquake really canstrike around us at any time,
can’t it?

A house whose ground floor was crushed completely:
Niigata Chuetsu Earthquake, 2004
*Photo provided by Tokyo Metropolitan University

It’s an earthquake! What would you do if one happened?
I’m scared! Earthquakes
are so powerful!

Earthquakes bring a variety of disasters.

Japan has suffered from many earthquakes and sustained a great deal of damage.
Due to their strong vibration of ground surfaces, earthquakes cause the collapse ofhouses and buildings, fires, landslides, or liquefaction of the ground. Occasionally,
many lives are lost due to these consequences. If earthquakes occur at the bottomof the sea, the resulting tsunami can do tremendous damage to large areas. An
example of this is the 2011 off the Pacific Coast of Tohoku Earthquake.

Fires caused by an earthquake: The Great Hanshin-Awaji Earthquake Disaster, 1995

An advancing tsunami wave: The Great East Japan Earthquake Disaster, 2011

*Photo provided by Mr. Katsuyuki Abe*Photo provided by Miyako City, Iwate Pref.

Landslides: The Iwate-Miyagi Nairiku Earthquake, 2008

Liquefaction: The Great East Japan Earthquake Disaster, 2011

*Photo provided by Iwate Pref.

*Photo provided by a voluntary disaster prevention troop from the Tomioka
Estate Housing Management Association of Urayasu City, Chiba Pref.

The Great East Japan Earthquake Disaster, which claimed many lives
The 2011 off the Pacific Coast of Tohoku Earthquake at 2:46 PM
on March 11, 2011, and the following tsunami (together causing
the Great East Japan Earthquake Disaster), inflicted enormous
damage on East Japan. It centered on East Japan’s Pacificcoast, and the number of people dead or missing amounted toapproximately twenty thousand. The earthquake destroyed or
swept away more than one million houses, as well as roads andrailroads. It also paralyzed services such as electricity, watersupply, gas, and telephone service. Many inhabitants were forced
to live in shelters or provisional houses for long periods of time.
Disaster victims speaking on specially-provided public
telephones: The Great East Japan Earthquake Disaster, 2011
*Photo provided by TOHOKU REGIONAL BUREAU MINISTRY OF LAND,INFRASTRUCTURE AND TRANSPORT

Japan is the world’s foremost “Earthquake Country”
Approximately ten percent of the world’s earthquakes occur in, or in the vicinity of, Japan.
Japan has been struck by approximately ten percent of the world’s earthquakes. This is despite
its small size, which is less than one percent of the world total land area. Including ones that we
can’t perceive, earthquakes occur at anytime, at anyplace. Japan is the world’s foremost earthquake country.

World distribution map of earthquakes (1988-2007)
Red dots show the locations of earthquakes at a depth shallower than 100 km that have had an earthquake magnitude greater than 5.0.

*Prepared by the Japan Meteorological Agency based on the data from USGS (US Geological Survey)

So, what actually is an earthquake?
Very large forces are acting on the rocks beneath the ground’s surface. When the rocks cannot
withstand the force any longer, they break along a certain plane in a sliding manner. This phenomenon is called an earthquake and the sliding plane is called a fault. The greater the fault andthe greater the sliding, the greater the earthquake becomes.
When an earthquake occurs, vibration propagates
through the rocks and shakes the ground surface. If
the shaking is large enough we feel the vibration of
the earthquake.
An earthquake
occurs

Hypocenter (The location that earthquake occurs)

Japan is the world’s foremost “Earthquake Country”
Pacific plate

Why do we have a lot of earthquakes in Japan?

Hawaii Islands

The surface of the earth is covered with more thanJapana dozen layers of hard rock, called “plates.” With
continents and oceans on top of them, the plates
Sinking
move slowly. When one plate collides with another
Sinking
and two plates squeeze together, stress is generatMantle
ed in the plates. This stress is the main cause ofearthquakes.
At the center of the earth there is the “core,” which has a high temperature (approximately
6000ºC), and around the core is the “mantle.” It is thought that the mantle undergoes a motion
called “convection,” which is like the boiling water in a pan over the fire, and that it is the convection that makes the plates move little by little.

The world’s plate boundaries

If you look at the places where earthquakes havestruck on a world atlas, you will find that earthquakes concentrate on belt-like zones along theplate boundaries.
(Compare with the “World Earthquake Distribution”
map on the left page.)*The white dotted lines on the map show unclear plate boundaries.

Philippine Sea plate
Eurasianplate

African
plate

North
Americanplate
Pacific plateIndo-Australian plate

South
Americanplate

Antarctic plate

The Japanese Archipelago and surrounding plates
There are four plates intricately intertwined around Japan. They are the Eurasian, North American, Pacific, and Philippine Sea plates. Japan is situated at a location where the plates are
jammed together. That is why we have a lot of earthquakes.
*The white dotted lines on the map show unclear plate boundaries.
North American platePlateboundaries
Eurasian plate
Pacific plate
Philippine
Sea plate

There are four plates around
Japan! No wonder we havea lot of earthquakes.

Japan is the world’s foremost “Earthquake Country”

We have various types ofearthquakes, don’t we?

Where do earthquakes occur?

We have earthquakes in various parts of Japan. However, based on the place andcause, there are several types of earthquakes, with each type having its own specific features. A typical type is one that occurs along an active fault. Another typicaltype is an earthquake that occurs near a plate boundary, which is called a ocean
trench type earthquake.

Continental plate

Oceanic plate

Active Fault Earthquake

Ocean trench type earthquake

Accumulated strain
Continental plate

late

Oceanic p
Drag-in
Fault

Generation of tsunami

When the movement of an oceanic plate exerts
force on the inside of a continental plate,earthquake can occur. This type of earthquake
sometimes occurs directly beneath a densely
populated area. If this happens, severe
damage can be inflicted on the region. The
1995 Hyogoken-nanbu Earthquake, which
triggered the Great Hanshin-Awaji Earthquake
Disaster, was of this type.
A fault along which earthquakes have struck repeatedly in the past and that more earthquakes are
anticipated in the future is called “an active fault.”

Continental plate

late

Oceanic p
Jumping up

When an oceanic plate sinks under a continental plate, the edge of the continental plate is
dragged downward. When the continental plate
can no longer withstand the force, it tries toresume its original position and at that time anearthquake occurs. This type of earthquake cansometimes be massive and is usually accompanied by a tsunami.

Japan is the world’s foremost “Earthquake Country”

Let’s try to understand thedifference between seismic
intensity and earthquake
magnitude!

What is the difference?
The difference between seismic intensity and earthquake magnitude
Seismic intensity indicates the strength of vibration at the point that an earthquake has
struck. Earthquake magnitude (M), on the other hand, indicates the size of an earthquake.
For instance, if an earthquake magnitude of 7 occurs, the seismic
intensity varies with the distance from the hypocenter (the point thatthe earthquake has occurred).

Hypocenter

Intensity 6
upper●Difference of the human body’s perception foreach intensity[Intensity 0][Intensity 1]

upper

lower

Imperceptible
to people.

Felt slightly bysome people
keeping quiet
in buildings.

High earthquake resistance[Intensity 5 upper][Intensity 2]

Felt by many people
keeping quiet
in buildings.

Intensity 4

lower

4

[Intensity 3]

Felt by most people
in buildings.

[Intensity 4]○Most people arestartled.
○Hanging objects suchas lamps swing
significantly.
○Unstable ornaments
may fall.

[Intensity 5 lower]○Many people are frightened
and feel the need to holdonto something stable.
○Dishes in cupboards and items
on bookshelves may fall.
○Unsecured furniture may
move, and unstable furniture
may topple over.

upper

Low earthquake resistance[Intensity 6 lower]○Many people find it difficult ○It is difficult to remain standing.
to walk without holding onto ○Many unsecured furniture moves andmay topple over.
something stable.
Doors may become wedged shut.
○Dishes in cupboards and○Wall tiles and windows may sustain
items on bookshelves aredamage and fall.
more likely to fall.
○In wooden houses with low○Unsecured furniture may
earthquake resistance, tiles may fall
topple over.
○Unreinforced concrete-block and buildings may lean or collapse.
walls may collapse.

High earthquake resistance

Low earthquake resistance[Intensity 6 upper]

High earthquake resistance[Intensity 7]

Low earthquake resistance○It is impossible to move without○Wooden houses with low earthquake resistancecrawling. People may be thrown
are even more likely to lean or collapse.
through the air.
○Wooden houses with high earthquake resistance○Most unsecured furniture moves, and is
may lean in some cases.
more likely to topple over.
○Reinforced-concrete buildings with low○Wooden houses with low earthquake
earthquake resistance are more likely to collapse.
resistance are more likely to lean orcollapse.
○Large cracks may form, and large landslides
and massif collapses may be seen.

Japan is the world’s foremost “Earthquake Country”

Tsunamis come to seaside regions.
Being surrounded by sea, Japan has been struck by large tsunamis many times in the past. Tsunamis are sea waves that are usually triggered by earthquakes. Japan is situated in the world’s most
tsunami-vulnerable region.

A fishing boat washed ashore by a tsunami:
The Great East Japan Earthquake Disaster, 2011
*Photo provided by Kesennuma City, Miyagi Pref.

Damage due to tsunami and post-earthquake fire
(The bare soil area in the foreground used to be a town):
The Hokkaido-nansei-oki Earthquake, 1993
*Photo provided by Mr. Katsuyuki Abe

Atsunami attack from acrossthe ocean

On December 26, 2004, a severe earthquake off
Sumatra Island, Indonesia, generated a tsunami.
It devastated nations along the Indian Ocean.
More than 280 thousand people were dead or
missing. In Sri Lanka, the tsunami arrived twohours after the earthquake and killed nearly forty
thousand people.

The progression of the tsunami thatwas generated by the earthquake

13 minutes after
the earthquake

After approx. two hours

India

ThailandSri Lanka

Malaysia

Indian Ocean
Indonesia*Images provided by Tohoku
University

How tsunamis are generated (in the case of seabed upheaval due to an earthquake)
Movement of seawaterContinental plate
The tsunami ispropelledforwardSeabed upheaval
Oceanic plate

When a large earthquake occurs in an
ocean, the seabed is either heaved
upward or it sinks. As a result, the seawater above the seabed is displaced. This
leads to the vast amount of seawater
being moved peripherally; this is called atsunami.

In deep seas, tsunamis travel fast. Whenthey approach shorelines and the water
depth decreases, the speed will decrease
but the height of the wave will increase. A
large tsunami can run up onto the land or go
up a river.

Japan is the world’s foremost “Earthquake Country”
If an earthquake occurs,
we have to watch out for atsunami!

What to do if a tsunami occurs.

Even if the vibration of an earthquake is small, a large tsunami could still come. Tsunamis aremuch more powerful than high tides caused by a typhoon. If an earthquake does occur and youlive in a seaside area or happen to be on seashore, keep the following in mind:g

mi warnin

Tsuna

A tsunami’s coming!

Here it comes again!

Don’t try to run “away” fromthe tsunami, try to get to “ahigher place.” If you feel astrong vibration, or if you feela jolt that is not that strong
but is long in duration, evacuate immediately.

If a tsunami warning isannounced, evacuate even if
you did not feel an earthquake. During a tsunami
advisory, refrain from sea
bathing or seashore fishing.

Tsunamis come again andagain. Once you haveevacuated, stay alert until
the tsunami warning or
tsunami advisory has been
lifted.

Tsunamis will increase theirheight rapidly when they
approach the shoreline.

Tsunamis can come up
rivers. Never go near thesea or a river.

Stay up to date through information from the radio, TV,
sound truck, or other sources.

Memo: Make note of the safety precautions for earthquakes near the seaside.

Prepare for an earthquake
If an earthquake occurs, the important things to do are: “not to panic,” ”to protect yourself,” and ”toact calmly.” Let’s consider what you would have to keep in mind when evacuating at your school,
outdoors, or at your home.

What if an earthquake occurred when you are at school…
Preparedness for evacuation
1. During violent shaking, stay under your desk.
2. Protect your head from falling objects.
3. Listen to your teacher before you act.
4. When evacuating, act calmly together.
5. Pay attention to falling objects from the ceilingor off shelves. Also look out for broken
window.
*Discuss other things to keep in mind with your classmates.

Let’s check the safety precautions for your route to school.
Imagine an earthquake occurring while you are outside, such as during your commute to andfrom school. Check out possible danger spots or possible shelters on or near the school route.
Possible falling objects
Roof tiles, broken window
glass fragments, etc.

Possible collapsing objects
Concrete block walls,
vending machines, etc.

Obstacles that might block
your path
Bicycles, signboards, etc.

fé

Ca

Memo: Make note of the points to pay attention to in case an earthquake occurs when you are in school or during your commute.

Prepare for an earthquake

Do a safety check in and around your house!
In a large earthquake, many people can get hurt or even killed by fallen furniture, falling objects, or
glass fragments. Check that there is nothing that could pose a danger during a disaster.

To protect furniturefrom toppling

To prevent injury from falling
objects or shattered glass

To prevent trapping
yourself in your house

Are concrete block
walls stable?

Furniture that is likely to topple,
such as cabinets or bookshelves, should be fixed withmetal fixtures or strut bars.

Do not put furniture or otherthings prone to toppling neardoors that you might use as anescape route.

The doors of furniture, such as a
kitchen cabinet, containing
breakable objects should be
fixed with fasteners to preventthe doors from opening.

Ask your family member if theconcrete block walls aroundyour house are stable.

Ask your family members the following:
Have you ever talked with your family about what you would do
if an earthquake were to suddenly strike? We should regularly
check what to do in the event of an earthquake.
Is my house robust enough to withstand an earthquake?
Are there dangerous places in the house?
Do I know where the evacuation shelter is and how to getthere?
Have we arranged in advance about where to meet if anearthquake were to occur?
Have we arranged how to communicate?
Are the items that we would need to take to the evacuation
shelter being kept readily available?

Keep items that you would need totake readily available.
If an earthquake were to occur, the water supply, gas, or electricity mightstop. In anticipation of such an occasion, keep enough water, food, andclothes for a family for three days or so readily available.
○Drinking water ○Boxes of matches, lighter ○Candles ○Clothes○Portable radio ○Flashlight (with extra batteries) ○Foods ○Valuables○First-aid kit ○Portable gas burner ○Rain gear ○Toilet paper, etc.

nk

Ba

k

boo

CrackerCannedfood

What is the
The system catches earthquakes quickly
earthquake
and notifies that a strong quake will
early warning? come within several to a dozen seconds.
What to do when you hear that a strong quake will comeIf you are at school

If you are out of doors

Listen to yourteacher’s instructions and protect
yourself. Youmight do this by
crouching under
your desk.

Step away froman object thatmight fall or
collapse, suchas a concrete
block wall.

If you are riding on

If you arein a crowded
place

a train or a bus
Holding on tohandles or otherfirm objects andprepare for thevehicle to stopsuddenly.

Do not rush to an
exit. Follow the
instructions of theperson in charge
and do not panic.

The above applies in the event of a sudden jolt.
Remember. For the Disaster Emergency Message Dial 171.
When an earthquake disaster happens, everybody tries to make contact with each other and telephone
connections may not work very well. If this happens you can use other means such as the “Disaster
Emergency Message Dial 171,” the “Web171 Disaster Message Board,” or the “Disaster Message Board
Service” for cell phones. If you are unable to make contact with your family, you can use the “Disaster
Emergency Message Dial 171”, for example. You can either leave a message or hear messages fromyour family. Let’s learn how to use the “Disaster Emergency Message Dial 171.”*Example of leaving your message: “I’m OK. I’ve taken refuge at XX Elementary School.”*You can use this service from a general subscriber phone, public telephone, cell phone, or PHS.
How to use “Disaster Emergency Message Dial 171” service (you can leave a message or hear messages with audio guidance)
To leave amessage
171 then 1
To hearmessages
171 then 2

To leave a message
To hear messages

Push 171 and then push 1.
Enter your phone number. (Do not forget to include your area code.)
Push 171 and then push 2.
Enter your phone number. (Do not forget to include your area code.)

The Earthquake and Disaster-Reduction Research Division, Research and Development Bureau, Ministryof Education, Culture, Sports, Science and Technology (Secretariat Division of the Headquarters for Earthquake Research Promotion)

100-8959 3-2-2 Kasumigaseki, Chiyoda-ku, Tokyo Tel: 03-5253-4111 (switchboard)■URL: http://www.jishin.go.jp/en/ Word to search: headquarters for earthquake Search(March 2014)