»1 Living with earthquakes
Earthquakes and volcanic eruptions can have disastrous effects,
especially if they happen in places where many people live.
Understanding the causes and effects of earthquakes and volcanoes
can help to reduce their effects on people and environments.
What are you going to learn about in this chapter?
> Where earthquakes and volcanoes happen
> Why earthquakes and volcanic eruptions happen
> The effects of earthquakes and volcanoes in different parts of the world
> How the effects of earthquakes and volcanoes can be reduced
A Earthquake in Kobe, Japan
> How a tsunami starts
> What it is like to live through a tsunami
> Why aid is needed after a natural disaster
> Why people live in active areas
What is the earth like?
> Understanding that the earth is not a solid mass
> Finding out that inside the earth it is very hot
The earth is made up of three main layers: the crust, the mantle and the
core (A). The crust is a thin surface which forms the land on which we live.
A The earth’s layers It floats on the semi-liquid (molten) mantle. The core is the centre of the
earth and is made of iron.
Huge blocks of the earth’s crust.
Scientists believe that:
• the inner core is solid, because it is so dense
• the outer core is molten rock.
Plate boundary The mantle is a layer of molten rock
Where plates meet. (magma) underneath the crust.
• Where land is on the surface it is
called continental crust and is usually
20–60 km thick.
• Where oceans are on the surface it is
called oceanic crust and is thinner –
usually between 8 and 25 km thick.
• In some places the crust is very thin
and molten material bubbles up to
the surface through cracks – these
are called ‘hot-spots’.
Geothermal Power Station Uses Hot Springs, Geysers Water heated up H O W H OT I S
hot underground rocks to produce underground rises to the surface under
hot water and electricity. enormous pressure.
T H E E A RT H ?
No one really knows
the answer to this
question, but we do
know that inside the
earth is hotter than the
outside. One way we
can tell this is when
volcanoes erupt or red
hot lava comes to the
earth’s surface. The
photographs in source
B show other evidence
which tells us that
temperatures are higher
inside the earth.
B Evidence to show that temperatures inside the earth are higher
6 geography 360° Foundation Book 3
T H E E A RT H ’ S C RU S T Continental Plate – plate with
land on the surface
The earth’s crust is not one solid mass. It is made up of large pieces Lava – molten rock on the
called plates (map C). Continental Plates have land on the surface and earth’s surface
Oceanic Plates have an ocean on the surface. The plates are slowly Magma – molten rock inside
moved around by currents inside the earth. Notice how in some places the earth
the plates are moving towards each other and in other places they are Molten – melted
moving apart. Plate boundaries are the places where plates meet – this is Oceanic Plate – plate with an
where earthquakes and volcanoes often occur. ocean on the surface
Plate boundary – where the
earth’s plates meet
I ra n
P h ili p p in e
P a c i f i c
Plate boundary (edge) Earthquakes
Antarctic 0 3000 Kilometres
Direction in which plate is moving Volcanoes
C The earths’s major plates
1 Copy out the following paragraph. Use the words 3 Look at source C.
in the box below to fill in the gaps. Start by putting a) Which plate does Britain lie on?
the heading: ‘What is the earth like?’
b) Why does Britain not have major earthquakes
The earth is made up of ______layers, the crust, and volcanoes?
the _______ and the core. The ______ is the part
c) Why is the edge of the Pacific Ocean often
we live on and is between 8 and 60 km thick. The
called ‘the Pacific ring of fire’?
mantle is made up of _______rocks called
_______. The core is in the _______ of the earth 4 Below are some sentences that describe the
and is made of ____________. location of volcanoes. Write out the two that
iron three molten mantle • There are volcanoes along the west coast of
magma centre crust South America.
2 How can you tell that it is hot inside the earth? • Britain has lots of active volcanoes.
Write a brief paragraph, starting with: ‘There are • The east coast of North America has lots of
many ways you can tell that it is hot inside the volcanoes.
earth …’ and go on to mention two ways you can • East Africa has a line of volcanoes.
tell it is hot inside the earth.
1 Living with earthquakes and volcanoes 7
Why do earthquakes and volcanoes
occur in certain places?
> Understanding that the earth’s crust is made up of a number
of separate pieces called plates
> Finding out why earthquakes and volcanoes happen near the
edges of the earth’s plates
The earth’s crust is made up of a number of huge pieces called plates.
These plates are moved by the currents in the hot rocks below the
surface. The edges of plates are called margins or boundaries.
H O W FA S T D O T H E P L ATE S M OV E ?
The plates move between 1 cm and 12 cm a year, which is about the
speed of growing fingernails! This does not sound very fast but don’t
forget that the earth is millions of years old, so a small movement can
make a big difference given enough time.
About 160 million years ago South America and Africa were next to each
other; today they are separated by the Atlantic Ocean (A).
H O W C A N W E TE LL T H AT T H E E A RT H ’ S
P L ATE S M OV E ?
2 Rock formations found in South America
and Africa are exactly the same, so they
Pl must have been formed near each other
1 Looking at the shape South America N
of South America
and Africa, it is clear A t l a n t i c
that they fit together O c e a n
like a giant jigsaw
3 Identical fossils of land-based
prehistoric animals have been
found in South America and
Movement Africa, so these continents
must have been joined
0 4000 Kilometres together 200 million years ago
A Plate movement
W H AT H A P P E N S W H E R E P L ATE S M E E T ?
Plates can move apart, push together or slide past each other. This
means that the area where plates meet is very unstable.
8 geography 360° Foundation Book 3
W H AT H A P P E N S W H E N T WO P L ATE S M OV E A PA RT ?
4 The tops of some of the mountains stick
up out of the ocean to form islands
3 Mountain ridges form under the sea Iceland
A t l a n t i c
O c e a n
E u r o p e
N o r t h
A m e r i c a 2 The molten rock cools into solid rock
1 Molten rock rises into the gap
Plate Molten Plate
B Plates moving apart
W H AT H A P P E N S W H E N A N O C E A N I C P L ATE
A N D A CO N T I N E N TA L P L ATE P U S H TO G E T H E R ?
5 Volcanic eruption
4 Liquid rock (magma)
rises to the surface
2 The plates push together,
causing earthquakes Pacific Plate
1 The heavier Pacific Plate
pushes under the Eurasian Plate
3 Rock begins to melt
C Oceanic and continental plates pushing together
1 Copy and complete the following sentences using 3 Write out these statements in the correct order to
the words in the box below. show what happens when plates move apart.
a) The earth’s crust is made up of a number of • Undersea ridges and mountains are formed
______. • Molten rock rises to the surface and cools
b) The plates are moved about by the ________ • Two plates move apart
4 Draw a diagram to show what happens when
currents plates oceanic and continental plates push together.
2 Explain how you can tell that South America and
– Volcano – Melting rock
Africa haved moved apart.
– Rising magma – Start of an earthquake
1 Living with earthquakes and volcanoes 9
What happens in an earthquake?
> Finding out why the earth shakes
> Learning about how earthquakes are measured
Epicentre – the point on the
earth’s surface above where
Most earthquakes happen when two of the earth’s plates stick as they
an earthquake starts push past each other (A).
1 Two plates moving 2 Suddenly the plates move, causing the
past each other get plate to jolt apart – sending vibrations
jammed together through the crust – an earthquake
The point on the surface
directly above the focus
is called the epicentre
Cr u Cr
The point underground where the
earthquake started is called the focus
A How an earthquake can happen
W H AT A B O U T T H E S T R E N G T H O F A N
E A RT H Q UA K E ?
FAC T F I LE
The strength of an earthquake is measured by the Richter scale. The
The word seismic is Greek for higher the number on the scale the greater the damage.
‘shake’. As earthquakes cause
the ground to shake, anything The Richter scale
to do with earthquakes is
called seismic! Measures the amount of energy released.
1 Only noticed by instruments
2 Barely felt
The Richer scale is Each number is ten
3 Slight vibrations
calculated using a times more powerful
4 Windows rattle, some movement, minor damage than the last
so is very accurate 5 Some damage to buildings
6 Walls crack, some buildings collapse
7 Ground cracks – many buildings collapse
8 Large areas destroyed 8.9 Strongest
9 Widespread destruction recorded earthquake
10 geography 360° Foundation Book 3
H O W A R E E A RT H Q UA K E S M E A S U R E D ?
An instrument called
a seismometer is
Calm Smaller eathquake
used to record the
shaking of the earth
collected is shown
on a seismograph
different places can
help to tell where an Time
earthquake started. B A seismometer C A seismograph
H O W D O E A RT H Q UA K E S C AU S E DA M A G E ?
Shaking causes Electrical cables damaged causing fires Buildings destroyed
buildings to collapse by the earthquake
River banks broken causing flooding
Shaking causes landslides
Gas pipes broken causing fires
Large trees fall causing damage
Earth movements cause bridges to collapse
1 What does the word ‘seismic’ mean? 4 Describe three ways in which earthquakes can
2 Draw a diagram like the one on the right. cause damage.
Add the words from the box below to explain how
an earthquake happens.
Crust Mantle Vibrations
Plate movement Focus Epicentre
3 Copy out and Type of damage Richter scale
complete the table,
which describes the Barely felt 2
effects of 4
different strengths. 6
Widespread destruction 9
1 Living with earthquakes and volcanoes 11
Case study: the Kobe earthquake – Japan
> Understanding the effects of an earthquake
> Finding out how people respond to earthquakes
CH Damage extends to 96
Hokkaido kilometres around Kobe
including temples in Kyoto N Kobe is the sixth largest city
in Japan and one of the
N. KOREA world’s largest ports.
J A PA N
At 5.46 am on 17 January
Kyoto 1995 the city was rocked by
Tokyo a massive earthquake (A)
Kobe Nearly 12,000
N buildings destroyed recorded at 7.2 on the
Many killed as parts of Richter scale.
Epicentre Hanshin Expressway collapse
In a matter of minutes one of
0 300 Kilometres the most modern cities in the
world had become a disaster
Tarumi Kobe area (B, C).
At 5.46 am local time tremors International
spread from island epicentre Airport unaffected
Osaka Bay FAC T F I LE
Kobe was Japan’s worst
earthquake for 72 years
6,310 people were killed
45,000 people were hurt
Wakayama 0 16 Kilometres 75,000 buildings were
Rebuilding the city cost over
A How the earthquake struck
B Damaged highway following the Kobe earthquake C Damaged buildings following the Kobe earthquake
12 geography 360° Foundation Book 3
‘There was a rumbling sound that got louder and louder. Everything started
to shake – a lot of buildings began to collapse. Most people did not have
W H AT WA S I T L I K E time to get out.’
TO L I V E T H RO U G H
T H E E A RT H Q UA K E ? ‘I was driving to work and the car was suddenly thrown across the road. All
These comments were made by the cars stopped. It was only later I was told that the road ahead had
people in the area at the time of collapsed, killing a number of people.’
the earthquake. Local factory worker
W H AT WA S I T L I K E
‘I was staying in a hotel and was woken up by a flash that lit up the sky.
FOR THE I was later told it was an electrical explosion. Everything began to move.
EMERGENCY It seemed to last for ages, but was probably only about 20 seconds.’
S E RV I C E S ? Visiting businessman
Local fireman Ambulance driver
‘The biggest problem was that fires ‘The biggest problem was getting
were breaking out everywhere. to people who needed help. Lots
Gas mains and electrical cables were of the roads and bridges were
damaged, causing thousands of fires. damaged. Others were blocked
We could not cope with them all.’ by buildings that had collapsed.’
REBUILDING THE AREA
Within two years of the earthquake, a lot of the damaged areas had been
To make sure that the effects of any future earthquakes are reduced, the
following measures have been put in place:
• Making sure that new roads are wider
• Leaving more space between buildings
• Using building materials that do not catch fire so easily
D Kobe city rebuilt two years after
• Making buildings stronger and more flexible the earthquake
• Not building on unstable ground
1 Write a heading ‘The Kobe Earthquake – Japan’.
Underneath the heading write down:
– when it happened Local resident Buildings began to shake
– how powerful it was and many collapsed
– the effects on people
– the effects on buildings. 4 a) Draw an outline sketch of photo B showing
2 Why might the effects have been worse if the how some roads were damaged.
earthquake had happened between 8.00 and b) Put labels on your sketch to describe the
9.00 am? main points. (See page 154 of SKILLS in
3 Complete a table like the one started here, which geography.)
describes one point made by each of the three 5 Explain how any one of the rebuilding ideas may
people talking about what it was like to live make the area safer if there is another
through the earthquake. earthquake in the future.
1 Living with earthquakes and volcanoes 13
What happened in the 2003 earthquake
> Learning about the effects of an earthquake in a developing
Caspian > Understanding the effects of an earthquake in a developing
I r a n On Friday 26 December 2003 at 5.27 pm a major earthquake hit the
Kerman Iranian city of Bam, a city of 80,000 people (A). The city is famous for its
2,000-year-old red brick citadel and fortress, which attracts thousands of
tourists each year.
Gulf W H AT C AU S E D T H E E A RT H Q UA K E ?
Arabia N The Iranian plate and the Arabian plate pushed together. This caused a
shockwave which was the start of the earthquake (B).
0 400 Kilometres
The following news reports describe what it was like in Bam after the
A Bam, Iran earthquake.
I r a n
0 400 Kilometres
C Bam Citadel before the earthquake B Plate movement causing the earthquake
QUAKE ROCKS A
day when an
were killed yester
Ove r 20,000 people m. With
t Iranian city of Ba
earthqu ake hit the ancien fears that
royed, there are
s of homes dest
thousand homeless in the
e from being left
many more will di
ty of over 80,000
Ba m is an ancient ci years old. It
ings over 2,000
man y mud brick build e badly
itals and both wer
only has two hosp
D Bam Citadel after the earthquake damaged by the
14 geography 360° Foundation Book 3
rning 40,000 people
Just before dawn this mo scue volunteers,
the dead. Re
an ear thquake devastated amedics are
city of Bam in Iran. Mud brick doctors and par
and being flow n to the country to
homes in the city ny of whom
were help sur vivors, ma
sur rounding villages everything.
to have lost
reduced to rubble and up
CITY OF BAM DEST
IN DEADLY EARTHQ
Thousands of homes
were more may die of cold or
destroyed when an earthq threat
uake of disease. The two hospita
hit the ancient Iranian ls in
city of the city have been damage
Bam yesterday. Over d so
20,000 people cannot get the hel
people were killed and p they
many desperately need.
D Emergency shelter after
BAM – ONE YEAR ON
It often takes poor countries a long time to rebuild after an earthquake.
A television reporter visited Bam a year after the earthquake and made
the following notes:
• There are still lots of homeless • Lots of new houses have been
• Lots of people are still living in • Most of the roads have been
tents on the edge of the city. cleared.
• Piles of rubble are everywhere.
1 Write the title ‘The Bam earthquake – Iran 2003’. Both _________ were damaged and people
a) Copy out and complete the following sentences. had to be flown 100 miles for medical help.
The number of people living in Bam is collapsed hospitals plates early
_____________. brick shake built
The ancient Citadel is _______ years old and
2 Copy out and complete the table below by adding
made from _______ _______. four other types of structures that may have been
b) Copy out the following passage, which damaged by the earthquake.
describes what happened in the Bam
earthquake. Use the words in the box below to
complete the passage. Houses Roads
The earthquake happened because the Iranian
and Arabian _________ moved together,
causing the ground to __________. It happened
__________ in the morning and many people 3 a) Why does it take a long time for poor countries
were asleep in their red _________ houses. to get back to normal after an earthquake?
Most houses were poorly _______ and b) List two things that have been done and two
__________ during the earthquake. things that are still needed a year after the
1 Living with earthquakes and volcanoes 15
What happens when a volcano erupts?
> Learning about different types of erupted material
> Understanding the effects of an erupting volcano
W H AT I S A V O LC A N O ?
A volcano is an opening or vent in the earth’s crust where different
materials are able to reach the earth’s surface (A–D).
W H AT S O RTS O F M ATE R I A L C A N R E AC H
T H E E A RT H ’ S S U R FAC E ?
Lots of different types of material can be forced up from inside the earth’s
crust during a volcanic eruption. Not all volcanic eruptions are explosive.
In places like Hawaii lava flows in channels and can be studied at quite
A Molten lava (liquid rock) can be: B Steam and volcanic dust often
– thick and sticky and move quite slowly Types of material come out of small eruptions.
– thin and runny and flow very quickly. erupted from the earth
C Red hot ash is erupted from many D Volcanic bombs – large blocks of hot rock – can be
volcanoes and is very dangerous. thrown hundreds of feet in the air during an eruption.
16 geography 360° Foundation Book 3
W H AT DA M A G E C A N A V O LC A N I C
E RU P T I O N C AU S E ?
Gas clouds can suffocate people.
Lava flows destroy everything in their path.
Volcanic bombs can
Ash can mix with water and form mud flows.
These can move down hillsides at over
50 mph destroying anything in their way.
Hot ash will burn
people and cause fires.
Rivers can be blocked by erupting
material, causing flooding.
Trees can be blown flat
by a volcanic blast.
Roads and bridges
can be washed away. Villages and towns can be Animals and crops
buried by flowing lava. can be destroyed.
A R E A LL V O LC A N O E S AC T I V E ?
Volcanoes can be active, dormant or extinct.
Active volcanoes have erupted recently and are expected to erupt
again. There are over a thousand active volcanoes,
many around the edge of the Pacific Ocean.
Dormant volcanoes have not erupted for many years but could still erupt.
Extinct volcanoes are not expected to erupt again in the future.
1 Copy out and complete the following sentences 3 Write a sentence about how volcanic eruptions
(look back to page 7 to help you): can damage each of the following:
Magma is … – People – Roads
Lava is … – Buildings – Farmland
2 Copy out and complete the following table to show 4 Research task Use the internet (see Hotlinks,
the different types of material that can come out page ii) to find two examples each of:
of erupting volcanoes. – active volcanoes
– dormant volcanoes
Material erupted from the earth
– extinct volcanoes.
5 Use the internet (see Hotlinks, page ii) to locate
Ash five volcanoes currently erupting.
1 Living with earthquakes and volcanoes 17
Case study: the eruption of Mount
> Understanding what it is like to live through a volcanic
> Finding out the problems of living with hazards in poor
A Mount Nyiragongo, Congo
On Thursday 17 January 2002 Mount Nyiragongo, a
volcano in Central Africa, began to erupt (map A). In the
Central African Republic Sudan lakeside city of Goma, ten miles to the south, the local
people had no idea of what was going to happen over
Cameroon the next two days.
Mount Nyiragongo is a steep-sided mountain, so when it
Democra tic a erupted, the lava flowed like a river towards Goma. As the
lava reached Goma, it began to cool, filling the streets
Gabon with thousands of tonnes of cooling rock (photo B).
W H AT WA S I T L I K E L I V I N G
Kinshasa T H RO U G H T H E E RU P T I O N ?
The following newspaper article and sources B and C
show what it was like to live through the eruption.
0 400 Kilometres
Source: Developed by Lyn Topinka, Cascades Volcano Observatory
of Goma lava and many
The African city to run for their liv
a volcanic ning nearly
was lit up by By early this mor
t as lava
eruption last nigh 300,000 people
e sides of looked like
poured from th Goma – the city
Mount Nyiragongo. n the edge
small vil- a ghost town. O
destroyed many of the city the
e its way
lages as it mad had been dest
towards Goma, on many buildings
of Lake Kivu. Bui seen burning.
the red hot
turned to ash by
B Destruction in the main street of Goma
18 geography 360° Foundation Book 3
C Experiences during and after the eruption
‘Many people are living on the streets.
They have no shelter and little food.’
‘The lava flowed through Goma and Aid worker
into Lake Kivu. Lots of people escaped by
boat. Some said the lava had heated the lake
up so much that it was like bath water!’
‘We had to leave our home. I tried to return a
few days later but everything was destroyed.’
‘I was working in the area. I
could not believe the noise and the
smell of chemicals as the lava flowed ‘The eruption was so
through the streets of Goma.’ powerful it woke me up and
Foreign worker shook my bed – and ‘Many local doctors stayed in
I was fifteen miles away!’ the area during the eruption and
Tourist in nearby town tried to help people. Thank
God they are safe.’
‘I was told that the lava was flowing
from Mount Nyiragongo at over
thirty miles per hour!’
‘There is no safe water for people to drink.
Student living in Goma We are very worried about disease.’
Local health worker
1 Copy out the following passage which explains 2 a) Choose a title for the photograph on the
what happened in Goma. Use the words in the box opposite page (B).
below to fill in the gaps. b) Describe three points from the photograph.
When Mount Nyiragongo ___________ a flow of 3 Copy out and complete the table below using
_________ moved towards the city of ________. It three more of the experiences in source C.
moved quickly because of the __________ slopes. Experiences of the eruption
The lava destroyed many farming __________ on
its way to Goma, forcing people to leave their
homes. On the edge of the city the Local resident Had to leave home
_____________ was destroyed, and many
buildings could be seen ____________. The
following day, the main streets of Goma were full 4 Why will it be difficult to get food and clean water
of thousands of tonnes of cooling ____________. to the people of Goma?
steep airport burning lava
erupted villages rock Goma
1 Living with earthquakes and volcanoes 19
How can earthquakes and volcanoes be
made less of a hazard?
> Understanding that prediction, planning and preparation can
> Learning about some of the methods used to reduce the risks
of earthquakes and volcanoes
C A N E A RT H Q UA K E S B E P R E D I C TE D ?
• We know that most earthquakes
happen near the edges of plates so
we can use instruments (A) to tell if
anything is happening in these areas.
• When there is movement
Emergency planning officer – gas is sometimes released
‘It’s not easy but there are – water levels change.
things we can look out for
• Small movements can be picked up
on a seismometer – this might tell us
that an earthquake is on the way.
A heavy weight at
the top stops the
A A laser detector
means that the PL ANNING FOR
building can sway E A RT H Q UA K E S
The following measures can reduce the
risks from earthquakes:
A broad base
makes the • Make sure bridges and roads are
building more strong enough to withstand
• Use building materials that don’t burn
• Leave bigger spaces between
buildings for emergency vehicles.
tremors ‘The biggest danger in an earthquake
is caused by buildings collapsing or
catching fire. It is possible to
construct buildings that are
earthquake proof – The TransAmerica
B TransAmerica Pyramid, San Francisco Pyramid in San Francisco is a good
example of this.’
20 geography 360° Foundation Book 3
W H Y I S P R E PA R AT I O N I M P O RTA N T I N A N
E A RT H Q UA K E Z O N E ?
BE PRou knowBEe yPREP C oose a safe place to she
sure y your hom lter in
■ Mak pital is.
cal hos family ■ Have spa
lo in your re batteries
ev eryone mobile phon for your
e sure if an
■ Mak at to do
e and a torc
ws wh ■ Prepare a
kno es. n earthquake
ake strik fixed
earthqu niture is
t – include fir
your fur ver. materials an st-aid
e sure topple o
■ Mak and cannot might need
d other things
to walls er in
to shelt to survive fo
a fe place couple of da ra
ose a s ys.
‘Preparation is not just making sure ■ Cho e.
that the ambulance, hospital, fire your ho
and police service know what to do –
it is also about preparing individual
people. This could save your life.’ C Earthquake preparation leaflet
W H AT A B O U T V O LC A N O E S ?
Before volcanoes erupt there are often warning signs If you know an eruption is going to happen, emergency
including: plans can be put in place. These might include:
• small earth tremors • moving people away from danger
• the side of a volcano begins to bulge or cracks • setting up emergency shelters with food, water and
appear warm clothes
• small eruptions giving off heat, ash or gas. • making sure emergency transportation is available.
1 Copy out and complete the following sentences by 3 What things other than first-aid materials might
adding the correct word from the box below: you put in an emergency earthquake kit?
______________ is about working out when 4 Copy out and complete the spider diagram to
something is going to happen. show what might happen before an earthquake
______________ is about making sure buildings strikes.
are well constructed.
______________ is about making sure people
know what to do if an earthquake strikes.
PREPARATION PREDICTION PLANNING
2 a) Draw a sketch of the TransAmerica Pyramid (B).
b) On your sketch write short notes explaining 5 Make up a poster to show how people should
what has been done to make the building safer. prepare for an earthquake. Be sure it has:
(See page 154 of SKILLS in geography.) – a clear heading – a number of points
– some drawings and colour to make it attractive.
1 Living with earthquakes and volcanoes 21
What is a tsunami?
> Understanding what causes a tsunami
> Finding out what can be done to reduce the effects of
In Japanese the word ‘tsu’ means wave and ‘nami’ means harbour, so the
word ‘tsunami’ really means ‘harbour wave’. It was called this because of
FAC T F I LE giant waves hitting the Japanese coast.
The highest recorded wave
created by a tsunami hit Japan W H AT C AU S E S A TS U N A M I ?
in 1921 and was just under Earthquakes or volcanoes create tsunamis. Sudden movements on the
90 metres high! seabed push water upwards and start a wave. In deep water the wave is
Over 80 per cent of tsunamis quite small, but moves very fast – often up to 500 mph. As the wave gets
occur in the Pacific Ocean. near to land, it slows down but gets much bigger. It swallows everything in
its way and can totally destroy coastal areas (source A).
H O W D O E S A TS U N A M I D E V E LO P ?
5 Coastal area flooded as
4 The wave gets the wave surges inland.
bigger as water
piles up behind it.
2 The seabed is moved up
and down, creating a wave.
3 As the sea becomes ter
shallower, the wave Shallo
increases in size.
s the w
1 The seabed is bed slow
shaken by an on sea
A Development of a tsunami
H I S TO R I C TS U N A M I S
Alaska 1946 1964 1965
Hawaii Colombia 1906
Papua New Guinea 1998
Sumatra 2004 Chile 1960 N
0 3000 Kilometres
B Location of historic tsunamis C Devastated coastal area following
22 geography 360° Foundation Book 3
H O W C A N Y O U P R E PA R E
F O R A TS U N A M I ? Keeps a close look Warn people who
out for earthquakes might be in danger
To help some countries prepare for tsunamis, the
Pacific Tsunami Warning System was set up. This
involves twenty-four countries in the Pacific Ocean
area. It is organised from the island of Hawaii, in so that
the centre of the Pacific Ocean (B).
P L A N N I N G F O R A TS U N A M I
In richer parts of the world, such as Japan, coastal Looks for changes when to move
in sea level patterns people away from
areas have been changed to help them cope with coastal areas
tsunamis. The diagrams in source E show how a
coastal area can be changed so that if a tsunami
occurs, the damage will be much less. D Pacific Tsunami Warning System
Without planning Area devastated by a tsunami
Possible height of tsunami wave Road
Normal sea level
With planning Planted forest Houses
Possible height of tsunami wave Sea wall Raised road
Normal sea level Beach
E How planning for a tsunami can help avoid disaster
1 Draw a sketch like the following one. 2 What does the word ‘tsunami’ mean?
3 What has to happen for a tsunami to start?
4 Which part of the world gets the most tsunamis?
water 5 What are the aims of the Pacific Tsunami
6 Describe the ways that a coastal area can be
changed to reduce the effect of a tsunami.
Put the words in the box below on your sketch.
Earthquake Small waves
Large waves Buildings destroyed
1 Living with earthquakes and volcanoes 23
Case study: the Indian Ocean tsunami –
> Understanding that an undersea earthquake can affect places
hundreds of miles away
> Finding out about the causes and effects of the Indian Ocean
On the 26 December 2004 one of the strongest earthquakes ever
recorded happened near the coast of north-west Indonesia (photo A). The
underwater earthquake sent huge waves racing across the Indian Ocean
and even reached the coast of East Africa – 4,000 miles away.
A Satellite image showing the W H AT C AU S E D T H E TS U N A M I ?
developing Indian Ocean tsunami
1 The Indo-Australian Plate
suddenly moved about 2 The resulting earthquake pushed
20 metres under the 6 metres of water upwards,
Indian Ocean. creating a massive wave.
India ys ia
Sri L atra
3 As the wave reached
the coastline it grew
in height. n esia
B The cause of the tsunami
Epicentre of earthquake
0 1000 Kilometres
W H AT WA S T H E R E S U LT I N CO A S TA L
FAC T F I LE AREAS?
• The tsunami killed over
• Over 1 million homes were
• The waves travelled at over
400 mph out at sea –
reducing to 30 mph near
• The height of the wave was
between 3 and 9 metres.
C Tourists fleeing as the tsunami wave approaches
24 geography 360° Foundation Book 3
Map D shows the immediate effects of the tsunami as massive waves
crashed onto the coastal areas surrounding the Indian Ocean.
India Calcutta Dhaka Thailand
Large area of the eastern coast I n d i a Western coast of southern
swamped by waves, particularly the Bangladesh Thailand badly affected,
cities of Madras and Pondicherry.
including the holiday resort
Deaths also reported in the Andaman of Phuket and Phi Phi Island.
and Nicobar Islands, and Kerala state. Pradesh
Bay of Bengal Laos
People reported to
N have been swept
Rangoon Thailand away from beaches
Tamil near the northern
Nadu city of Penang.
Madras Andaman Bangkok
Maldives Andaman Is Sea
High waves and floods Pondicherry
Two-thirds of the low-lying Kerala
capital, Male, reported to be INDIAN Gulf of
under water. Trincomalee OCEAN Thailand
Mutur Phuket Indonesia
v e s
Colombo Province of Aceh on
Nicobar Is Phi Phi Island northern tip of
Sri (India) Sumatra island badly
l d i
Penang hit, including capital
Male Banda Aceh Banda Aceh.
3 hours 2 hours 1 hour M a l a y s i a Dozens of buildings
destroyed in the initial
Sri Lanka floodwaters washed
Wide stretch of eastern and southern coast over the region.
devastated by massive waves, and national Sumatra
Districts of Mutur and Trincomalee apparently Epicentre of earthquake
0 500 Kilometres inundated by waves as high as 6 metres. 9.6 kilometres below
Part of the capital, Colombo, shut by floods. seabed 7.59 am local time. Indonesia
D Immediate effects of the tsunami
Source: NI Syndication
1 Copy out the following points in the correct order 3 Put a title ‘The effects of the tsunami’.
to explain what caused the tsunami: Copy out and complete the following table, which
• The sea was pushed upwards. describes some of the effects of the tsunami in
• The waves moved towards the land. different countries.
• There was a massive earthquake. Counry Effects
• Waves were created.
Sri Lanka A lot of areas flooded
2 a) What are the names of the two plates that
moved, creating the earthquake? A lot of damage
b) By how much did the plates move?
1 Living with earthquakes and volcanoes 25
Living through the Indian Ocean tsunami
> Learning about how it feels to experience a tsunami
> Understanding that hazards can have both short- and long-
When the tsunami struck the coastal areas surrounding the Indian Ocean
millions of people were affected, including thousands of holidaymakers
who had gone to the area for a ‘sunshine break’ during the Christmas
holidays. The following resources give an impression of what it was like to
live through the tsunami.
Thousands of people were swept to
deaths yesterday as a giant wave hit
holiday beaches of south-east Asia
Beach resorts across the reported a low groaning
area – from Thailand to Sri noise before the waves
Lanka were ripped apart by crashed against the build-
a wave of water up to ings. The waves were so
nine metres high. powerful that they totally
There was little warning as destroyed buildings and
the wave of water swept picked up cars and trucks –
across the area. People moving them miles inland.
As millions of people
were going about
their daily lives, they w
ere totally unaware
of the horrors facing th
People were not to kn
that the gentle swaying beaches, many based
of skyscrapers in Sing on the fishing industry
a- More recently, th .
pore was the result of e tourist
an industry has de
earthquake which wa veloped
s with large resorts
about to bring a wall and
of holiday homes
water crashing down dotted
on along the coas
their homes. t. When
Towns and villages ha the wave struck, man
ve of these area y
grown up near th s were
e totally destroyed.
26 geography 360° Foundation Book 3
0 1000 Kilometres
‘We were sitting in our bedroom and
heard an enormous roar. Seconds later the door
burst open and the room filled up with water. We were THAILAND
swept out of the windows, but managed to ‘We were on a diving boat and were thrown around by
struggle towards higher land the waves. The boat was taken inland by the wave and stuck between
– and safety.’ two buildings. We climbed to the roof of a hotel. We were
lucky to survive.’
‘I was just going for a swim in the pool when a giant wave appeared.
The wave knocked me down several times – it was very strong. I was hit by trees,
I n d i a tables and other things, but managed to struggle to safety. I am covered in
Burma cuts and bruises, but am lucky to be alive – so many people in
the area have lost their lives.’
P h i l i p p i n e s
I n d i a n
O c e a n
Lanka M a l a y s i a
I n d o n e s i a
‘There was no warning. The first wave crashed through
the buildings – many of which collapsed. Everything was swept along by
the waves – even cars and lorries.’
‘The water levels are now going down, leaving a scene of total
devastation. Most local people have
lost their homes.’
A Interviews with British holidaymakers affected by the tsunami
1 What information do the newspaper reports give 5 Write a short paragraph to describe the experience
about: of holidaymakers in India, Thailand and Sri Lanka.
– the size of the waves? 6 The following point was made in a radio interview
– the power of the waves? by an aid worker:
2 What happened in Singapore to suggest that an ‘Many people are drinking dirty water and eating
earthquake had occurred? food picked up from the streets. They are also
having to sleep in the open.’
3 Why do a lot of people live on the coast in this
area? What problems might this cause for people in the
next few weeks?
4 Describe what is happening in the photographs on
the opposite page.
1 Living with earthquakes and volcanoes 27