GCSE

Geography

Unit One: The Restless

Earth

Question 1.

The Restless Earth Revision Checklist:

1. Read through your notes and tick off whether you have notes on the topics that have been covered. If not, you

must copy up ASAP.

2. For each topic you must provide a score to reflect how well you think you understand what you’ve covered.

This will help you focus your revision. Provide a score of 1-5.

3. Identify the topics you most need to revise – and do this as a priority!

1 = Don’t understand 3 = Understand some 5 = Understand all

Section of Topic Pages: Understanding?

PLATE MARGINS:

Tectonic plates: the distribution, and contrasts between continental and oceanic.

Plate margins: destructive, constructive and conservative.

3/4

TECTONIC LANDFORMS:

Location & formation: fold mountains, ocean trenches, composite volcanoes and shield volcanoes.

3/4

FOLD MOUNTAIN RANGE CASE STUDY:

Case study: the ways in which the range is used – farming, hydroelectric power, mining, tourism and how people adapt to limited communications, steep relief & poor soils.

4/5

VOLCANOES:

Characteristics: shield, composite and supervolcanoes.

Case study: of a volcanic eruption – the causes, primary & secondary effects, positive & negative effects, immediate & long term responses.

Management: monitoring and predicting volcanic eruptions.

6/7

SUPERVOLCANOES:

Characteristics: The characteristics of a supervolcano and the likely effects of an eruption (social, environmental, economic & global, local, national).

8

EARTHQUAKES:

Effects & responses: how the effects of an earthquake, and the responses to an earthquake vary between more economically and less economically developed countries.

Case study: A case study of an earthquake in a rich part of the world – their specific causes; primary and secondary effects; immediate and long-term responses – the need to predict, protect and prepare.

Case study: A case study of an earthquake in a poor part of the world – their specific causes; primary and secondary effects; immediate and long-term responses – the need to predict, protect and prepare.

9/10

TSUNAMIS:

Case study: A case study to show the causes, effects, and responses.

11

Tectonics

Can you provide definitions for the following key terms?

Inner core, outer core, mantle, convection current, crust, oceanic, continental,

subduct, ocean trench, fold mountain, natural hazard, composite and shield

volcanoes, magma, lava, crater, magma chamber, volcanic bombs, lahar,

pyroclastic flow, tiltmeter, supervolcano, caldera, fissure, geothermal, geyser,

hotspot, subsistence farming, irrigation, terraces, HEP, focus, epicentre,

primary/secondary/surface seismic waves, magnitude, Richter scale, Mercalli

scale, predication, protection, preparation, tsunami, primary effect, secondary

effect, immediate response, long-term response, aid.

http://www.bbc.co.uk/learningzone/clips/topics/secondary/geography/natura

l_hazards_tectonic_activity.shtml

Structure of the Earth

The earth consists of four concentric layers; inner core, outer core,

mantle and crust.

The inner core:

the centre of the earth and is the hottest part

it is solid iron and nickel with temperatures of up to 6500°C.

with its immense heat energy, the inner core is like the engine

room of the Earth.

The outer core:

surrounds the inner core

it is a liquid layer of iron and nickel

temperatures around 5,500°C at the boundary with the mantle.

The mantle:

is the widest section of the earth

it is made up of semi-molten rock called magma

it is the convection currents within the magma that cause

continental drift

The crust:

is the outer layer of the earth.

it is a thin layer between 0-70km thick.

there are two different types of crust: the less dense

continental crust and the denser oceanic crust.

Convection currents

Continental drift / plate movement

is caused by convection currents within the mantle

the temperature at the boundary of the outer core & the

mantle is about 5,500°C.

the magma here is heated, becomes less dense and rises

towards the crust.

as it rises the magma cools, becomes denser & drags the plates

along the surface of the mantle as it sinks. This cycle is

repeated forming a convection cells.

Plates and plate boundaries

The surface of the earth is like a jigsaw made up of plates

There are 2 types of plate:

Oceanic – new material (igneous), dense

Continental – older material (igneous, metamorphic and

sedimentary rocks), less dense

The point where two plates meet is called a plate boundary.

Earthquakes and volcanoes are most likely to occur either on or near

plate boundaries.

Types of plate boundary

The earth's plates move in different directions. Plates behave

differently at different plate boundaries:

Plate Boundary Diagram Description Example

Constructive plate boundaries

Constructive plate

boundaries occur when two

plates move away from

each other

North

American and

Eurasian

Plate

Destructive plate boundaries

Destructive plate

boundaries occur when an

oceanic plate is forced

under (or subducts) a

continental plate

Nazca and

the S.

American

Plate

Conservative plate boundaries

Conservative plate

boundaries occur when two

plates slide past each

other.

North

American

Plate and the

Pacific Plate

Collision plate boundaries

Collision plate boundaries

occur when two continental

plates move towards each

other.

Indo-

Australian and

the Eurasian

Plate

What happens at a constructive boundary?

Eg. N. American and Eurasian Plates forming the Mid-Atlantic Ridge

the plates are forced apart by convection currents in the

mantle.

Magma rises from the mantle, reaches the surface, cools and

solidifies to form new crust made up of igneous rock.

This process is repeated many times forming mid-ocean ridges

e.g. the Mid-Atlantic Ridge on the boundary of the N. American

& Eurasian plate & shield volcanoes like Surtsey and island arcs

like the Lesser Antilles

Oceanic crust

Ocean ridge

Mantle

Volcanic

islands

Plate movement

Seafloor spreading

MID-OCEAN RIDGES

mid-ocean ridge is general term for an underwater mountain

system formed at a constructive plate boundary.

This type of oceanic ridge is characteristic of seafloor

spreading.

The mid-ocean ridges of the world are connected and form a

single global mid-oceanic ridge system that is part of every

ocean

Rift

Valley

What happens at a destructive boundary?

E.g. The Juan de Fuca Plate & the N. American Plate forming the

Cascade Range & Mount St Helen’s, USA

the plates move towards each other

on the surface this forms a trench at the point where the 2

plates meet & fold mountains formed as the sediment on the

sea bed is uplifted

this uplifted sediment forms fold mountains

the oceanic plate is denser than the continental plate & is

forced underneath (subducted) the continental plate. The point

at which this happens is called the subduction zone.

the subducted oceanic plate pulls sea water with it

as it sinks into the mantle the water turns to steam and this

combines with the melting plate to form explosive magma.

This magma then rises up through cracks in the continental

crust eventually forming composite volcanoes.

Subduction zone mantle

Oceanic plate Continental plate

Fold mountains & composite

volcanoes

Plate movement

OCEAN TRENCHES

CONTINENTAL SLOPE: The continental slope gradually rises from the

abyssal plains but climbs as much as 45 degrees as it approaches land.

CONTINENTAL SHELF: The continental shelf, the region from the

coastline to the edge of the continental slope, covers about eight percent

of the global seafloor area. The continental shelf is a national asset for

most nations. It is a source of fish, both commercial and sport, and in

some areas, oil and natural gas

ABYSSAL PLAINS: Abyssal plains are found next to the continental

slopes at depths greater than 9 - 10,000 feet. They are areas of near

freezing water temperatures where there is no season or sunlight. The

Abyssal plain is regarded as the true ocean floor. The few marine

inhabitants found in the region survive only because they have adapted to

the hostile environment of bitter cold and immense pressure.

What happens at a conservative boundary?

e.g. Pacific & N. American Plates forming the San Andreas Fault

the plates move parallel to each other, get stuck, pressure

builds and is suddenly released in earthquakes

the landscape has a crumpled appearance

no land is created at a conservative boundary and none is

destroyed.

volcanoes do not occur along these boundaries

earthquakes are very common.

What happens at a Collision Plate Boundary?

E.g. The Indo-Australian & the Eurasian plates forming the

Himalayas

an area of sea separates two continental plates, sediment is

eroded and weathered from the land & settles on the sea floor

in depressions called geosynclines.

these sediments gradually become compressed into

sedimentary rock.

the two continental plates move towards each other,

compressing the layers of sedimentary rock on the sea floor

which become crumpled and folded to form fold mountains

eventually the sedimentary rock appears above sea level as a

range of fold mountains.

Where the rocks are folded upwards, they are called anticlines.

Where the rocks are folded downwards, they are called synclines.

earthquakes are common at such boundaries

The Andes Fold Mountains

Background:

The Andes formed at the

destructive plate boundary

between the Nazca & S.American

Plates

The world's longest fold mountain

range running for over 7,000km and

covering 6 countries.

Location:

Farming:

best land can be found on the valley

floors

terraces have been dug into the

valley sides and held up by retaining

walls has been used to bring the

lands on the valley sides into food

production.

most crops are grown in the lower

areas and include soya, maize, rice

and cotton

the main crop of the Andes is the

potato

most farming is subsistence,

Llamas have historically been used

a lot in the Andes, as a form of

transportation and to carry goods.

Alpaca, a relative of the Llama, has

been used to produce some of the

finest cloth known to man, and is

also produced in the Andes

mountains

Tourism:

Tourism is a key industry for Peru

in the East you can take part in

Eco-tourism activities in the

Amazon Basin, as found along the

Madre De Dios River near to Puerto

Maldonado.

Peru has some fantastic coastline

as well, but the highlight of Peru is

undoubtedly the Inca Trail.

The Inca Trail

covers 50km of old pathways

linking together old Inca

settlements in the inhospitable

mountains of the Andes.

South America's best known trek

and is one of only 23 World

Heritage Sites

The route takes 4 days and covers

around 45km, and finishes with

sunrise at the "Lost City of the

Incas" at Machu Picchu

the trail is strictly controlled, and

only 200 trekkers are allowed to

start out on the trail every day.

Mining:

The Andes mountains contain a

wide range of minable materials

There are large deposits of coal, oil

and natural gas, iron ore, gold,

silver, tin, copper, phosphates and

nitrates and Bauxite

The Yanacocha gold mine in Peru is

the largest gold mine in the world -

an open cast mine and the rocks

containing the gold are blasted with

dynamite. The nearby town of

Cajamarca has grown from 30,000

when the mine started to 240,000

people in 2005.

HEP:

deep river give the Andes huge

potential as a region to produce

hydroelectric power

narrow valleys cut dam costs

the steep relief increases water

velocities allowing electricity

generation

Snow melt fuels most of the water

provision - but this means that HEP

production can be reduced to small

amounts in winter.

The El Platinal Project is under

construction in Peru & will join the

Yuncan dam

The Alps

Background:

High mountain ranges, e.g. Mont

Blanc which is 4810m above sea

level

Contrasting microclimates on north

facing (ubac) and south facing

(adrete) slopes.

Geologically young (30 – 40 million

years old).

Location:

Located in France, Switzerland,

Austria & Slovenia

Farming

Most farms located on sunnier

south-facing slopes

Traditional system is Called

transhumance – cattle taken up into

alpine pastures during summer &

brought back down to the valleys

for the winter

Farmers now use artificial feeds

some livestock often stay in the

valleys all year

Tourism:

Tourism is a key industry

All year round – hiking, climbing &

winter sports

For winter tourism (St Moritz & Chamonix)

Flatter land at higher levels easy for

building hotels etc.

Steep slopes above resorts for ski

runs

For summer tourism:

Large glacial lakes on valley floors

Beautiful mountain scenery

Chocolate box villages

Good transport links throughout Europe

High numbers of tourist are damaging the

environment

Forestry

Forestry on north-facing slopes

Wood has always been the main

building material

Sawmills are located on valley floors

Timber not used for construction

turned into paper, pulp & fuel

HEP:

Narrow valleys are easy to dam

Hep used to power sawmills & a range

of industries

A textbook volcano

Composite & shield volcanoes

COMPOSITE VOLCANOES SHIELD VOLCANOES

Tall cone with narrow base & steep

sides

Cone with wide base & gentle slopes

Made of alternate layers of lava &

ash

Basic lava

Long periods of dormancy followed

by explosive eruptions

Regular eruptions of little violence

Occur at destructive plate

boundaries

Occur on constructive plate

boundaries

Mt St Helen’s, USA

Soufriere hills, Montserrat

Hekla & Surtsey in Iceland

Mauna Loa & Kilauea in Hawaii

MOUNT ST HELEN’S VOLCANO

A Case Study of a volcanic eruption in a richer country

Background info:

Mt St Helen’s is in a range of fold

mountains called the Cascade

Range in Washington State, USA

It is a composite volcano

Causes:

Cascades have been formed by a

destructive plate boundary

The Juan de Fuca Plate is being

subducted beneath the North

American Plate

Key Events:

March 1980 - earthquakes

followed by ash & steam eruption

From March a bulge grew on the

northern flank of the mountain

08.32 on 18th May 1980 an 5.2

earthquake caused a landslide on

NE side of the mountain causing a

lateral blast in the form of a

pyroclastic flow - blast removes

390m summit

Glaciers melted & formed lahars

which swept away trees and rock

choking rivers

2010 -A new magma dome is

growing

Primary Effects:

Total destruction up to 27km

north of crater

57 dead - had it not been a

Sunday, the number would have

been greater

crops were ruined and livelihoods

of loggers were devastated with

large areas of trees being

flattened like matchsticks – 15000

acres destroyed

lava flows and ash filling in Spirit

Lake and log jams and ash blocking

the channel of the Toutle River

Secondary Effects:

Ash fell over 3 states causing havoc in

towns like Yakoma, Washington

Ash fall caused poor visibility on

highways causing accidents

Power lines came down causing power

cuts

Toutle & Colombia Rivers filled with

ash & debris

Unemployment in the immediate area

rose tenfold in the following weeks

Damage estimated at over £800

million

Soil will become fertile in time

Short-term Responses:

USGS monitored volcano

11km exclusion zone was set up

around the crater based on

previous eruptions

National Guard helicopters

mobilized for search & rescue

Washington State introduced a

15kmph speed limit & encouraged

people to stay indoors

Long-term Responses:

US government gave $951million in

aid to rebuild the local economy &

compensate people

Roads & bridges rebuilt, rivers

dredged

Forest is being replanted & re-

colonized naturally

The area was given National

Monument status in 1982 and

received $1.4 million for

development - it draws 3 million

tourists / year

Damage to forests & debris from

lahars & pyroclastic flows has

increased the risk of flooding in

the area

SOUFRIERE HILLS VOLCANO, MONTSERRAT

A Case Study of a Volcanic Eruption in a poorer country

Background info:

Montserrat is part of the Lesser

Antilles

Population 11,000 before eruption

First eruption July 1995 - still

active

Causes:

Montserrat sits on a destructive

plate boundary

The North & South American

Plates are being subducted under

the Caribbean Plate

Primary Effects:

July 1995 - ash eruption. Now 2/3

island covered in ash

August 1997 - pyroclastic flows -

19 dead, two thirds of houses in

Plymouth destroyed. Forest fires

rage

Pyroclastic flows & lahars block

valleys & cause flooding

Many schools destroyed

Tourism ceased

Crops destroyed by ash

15 square miles in north of island

considered safe zone

Secondary Effects:

As most of the southern area was

destroyed any remaining inhabitants

have had to endure harsh living

conditions in the North.

Transport remains a problem for

people travelling to the island as the

port and airport remain closed.

The tourist industry is still

suffering with few visitors except

for cruise ships looking at the

volcano

3,000 people have not returned

Short-term Responses:

USGS monitored volcano & set up

warning systems

August 1995 - Safe Zone was set

up in the north of the island

UK government sent £17 million in

aid including temporary buildings &

water purification systems

People began to emigrate - by 1997

the population had dropped to 3500

USA & Royal Navy helped with

evacuation

Long-term Responses:

People moved back - current

population is about 8,000

UK government funded a 3 year

development programme - schools,

houses, medical facilities,

infrastructure - cost £122.8million

Vegetation is growing back in south

part of the island

Soufriere Hills has become a tourist

attraction

Why do people live near volcanoes?

1. Time - most volcanoes are perfectly safe for long periods in between

eruptions, and those that do erupt more frequently are usually thought

of, by the people who live there, as being predictable - about 500 million

people live

2. Minerals - copper, gold, silver, lead and zinc are associated with rocks

found deep below extinct volcanoes. Hot gasses escaping through vents

also bring minerals to the surface, notably sulphur, which collects around

the vents as it condenses and solidifies. Locals collect the sulphur and sell

it.

3. Geothermal Energy - Countries such as Iceland make extensive use of

geothermal power, with approximately two thirds of Iceland's electricity

coming from steam-powered turbines. It is a clean, sustainable source of

energy

4. Fertile Soils – volcanic rock is mineral rich & weathers into rich soils..

5. Tourism -Around the volcano may be warm bathing lakes, hot springs,

bubbling mud pools and steam vents. Geysers are always popular tourist

attractions, such as Old Faithful in the Yellowstone National Park, USA.

Iceland markets itself as a land of fire and ice, attracting tourists with a

mix of volcanoes and glaciers, often both in the same place.

How are super volcanoes formed?

Super volcanoes erupt infrequently

They emit at least 1,000km3 – 1,ooo times more than Mt St Helen’s

They do not have cones, but are huge basins called calderas

Super volcanoes form over hotspots

Magma rises from the hotspot & uplifting the crust into a dome

Cracks appear on the surface – gas, lava & ash erupt from the magma chamber

As the magma chamber empties the dome collapses forming the caldera

YELLOWSTONE NATIONAL PARK SUPER VOLCANO

A Case Study

Background info:

Super volcanoes emit at least

1000km2 of material

Do not have a cone

Form in a caldera (basin) often

bordered by high ridges

Super volcanoes do not occur at

plate boundaries but over hot

spots within plates

Yellowstone National Park is in

the USA

It erupts about every 630,000

years & is due

Causes:

Yellowstone National Park is

sitting above a hot spot

It has a magma chamber 80 km

long, 40km wide & 8 km deep

This is currently rising at around

70cm a year below Yellowstone

lake

Geothermal activity is

responsible for geysers such as

Old faithful

Potential Effects:

The destruction of 10,000km2

87,000 dead

15cm of ash would cover

settlements within 1000km

bringing the economy to a

standstill

1 in 3 people affected will die

Transport, electricity, water &

agriculture will be affected

Ask would fall on UK five days

later

Global climate would be affected

- temps would drop between 3 &

5 degrees Celsius

Crops would fail & famine would

follow

Potential Responses:

Emergency planning by US

government based on USGS

predictions

UN led relief effort

Migration from countries

affected by famines especially in

poorer parts of the world

Increased regional tensions

possibly leading to war

Managing tectonic hazards – prediction, protection & preparation

It's not possible to prevent earthquakes and volcanic eruptions. However, careful

management of these hazards can minimise the damage that they cause. Prediction is

the most important aspect of this, as this gives people time to evacuate the area and

make preparations for the event.

Predicting & monitoring eruptions

As a volcano becomes active, it gives off a number of warning signs. These warning

signs are picked up by volcanologists (experts who study volcanoes) and the volcano is

monitored.

The key techniques for monitoring a volcano

Warning signs Monitoring techniques

Hundreds of small earthquakes are caused as

magma rises up through cracks in the Earth's

crust.

Seismometers are used to detect

earthquakes.

Temperatures around the volcano rise as activity

increases.

Thermal imaging techniques and

satellite cameras can be used to

detect heat around a volcano

When a volcano is close to erupting it starts to

release gases. The higher the sulfur content of

these gases, the closer the volcano is to erupting.

Gas samples may be taken and

chemical sensors used to measure

sulphur levels.

Preparing for an eruption

A detailed plan is needed for dealing with a possible eruption. Everyone who could be

affected needs to know the plan and what they should do if it needs to be put into

action. Planning for a volcanic eruption includes:

Creating an exclusion zone around the volcano.

Being ready and able to evacuate residents.

Having an emergency supply of basic provisions, such as food.

Funds need to be available to deal with the emergency and a good communication

system needs to be in place.

EARTHQUAKES What causes an earthquake?

An earthquake is the shaking and vibration of the Earth's crust due to

movement of the Earth's plates (plate tectonics)

Earthquakes can happen along any type of plate boundary.

Earthquakes occur when tension is released from inside the crust. Plates do not

always move smoothly alongside each other and sometimes get stuck. When this

happens pressure builds up. When this pressure is eventually released, an

earthquake tends to occur.

The point inside the crust where the pressure is released is called the focus.

The point on the Earth's surface above the focus is called the epicentre.

Earthquake energy is released in seismic waves. These waves spread out from

the focus. The waves are felt most strongly at the epicentre, becoming less

strong as they travel further away.

Measurement of earthquakes

The Richter Scale

This measures magnitude

An earthquake's magnitude (power) is measured using an instrument

called a seismometer.

The scale is logarithmic – there is a tenfold increase in power every time

the scale increases by 1

So a scale of 2 is 10 times more powerful than 1 and a scale of 3 is 100

times more powerful than 1

The Mercalli Scale

Measures the effects (damage) of an earthquake using a scale between 1 & 12

It is based on subjective descriptions – good for on the scene analysis of

damage for emergency response

What factors affect the impact of an earthquake?

Distance from the epicentre

Rock type – resistant rocks provide more solid foundations for buildings

Magnitude - the higher on the Richter scale, the more severe the earthquake is.

Level of development – richer countries are more likely to have the resources and

technology for monitoring, prediction and response.

Population density (rural or urban area). The more densely populated an area, the more

likely there are to be deaths and casualties.

Communication - accessibility for rescue teams.

Time of day - influences whether people are in their homes, at work or travelling.

The time of year and climate will influence survival rates and the rate at which disease

can spread.

NB: As a rule, the poorer the country, the greater the impact of the disaster

KOBE EARTHQUAKE

A case study of an earthquake in a richer country

Background info:

Kobe is an important industrial city

located on Honshu Island, Japan

17TH January 1995 - 05.46am –

many were in bed

7.2 Ricter Scale - 20 seconds

duration

Physical Causes:

Kobe sits on the Nojima Fault Line

on a destructive plate boundary

between the Philippines & Eurasian

Plates

Shallow focus – 20km beneath

Awaji Shima Island in the bay of

Kobe

7.2 Richter Scale – 20 seconds

duration

05.46am meant many in bed

Human Causes

Buildings built close together –

domino effect

Buildings built before 1981

were not earthquake proof

SICUAN EARTHQUAKE, CHINA

A Case Study of an Earthquake in a poorer country

Background info:

Sichuan is in China - an LEDC

12th May 2008 at 2.28pm

7.9 Richter Scale - duration

120seconds

200 aftershocks - 3 measuring

over 6 Richter scale

Epicentre near Wenchuan

Physical Causes:

Sichuan sits on a collision Plate

boundary

The Indo-Australian Plate is

colliding with the Eurasian

Sichuan is a mountainous province &

prone to landslides

Human Causes:

LEDC – poor quality construction

Limited emergency response services

Primary Effects:

69,000 dead

18,000 missing

374,000 injured

5 million homeless

Wenchuan cut off by landslides

Beichuan - 80% buildings damaged

Shifang -chemical plants collapsed

killing thousands & spilling toxic

waste

900 schools collapsed

Secondary Effects:

Many dams were damaged &

power supplies cut

Landslides cut roads & blocked

rivers leading to fears of

flooding

5,000 tents flown in on DFID

flights

5,000 villages cut off -

daunting task of rebuilding

communities and livelihoods

1 million left unemployed

Reconstruction costs put at $150

billion

Short-term Responses: Heavy rains & mudslides made rescue

difficult

20 helicopters sent to disaster areas

50,000 soldiers sent - some troops

were parachuted in – not emergency

search & rescue specialists

Shelter, food & water provided

Land flattened for camps - 3million

tents called for

14th May China asked for

international help by text message

Red Cross donated £100 million in aid

Long-term Responses:

Over a million temporary homes

constructed in Sichuan over 3 years

Chinese government pledged

£10million to rebuild area

Banks wrote off debts

Dams & infrastructure rebuilt

Schools rebuilt on steel pole

foundations & lightweight thatch

The Haiti Earthquake 2010

A Case Study of an Earthquake in a poorer country

Background info: Location: Caribbean nation of

Haiti- 15km (10 miles) south-west

of Port-au-Prince ( capital of Haiti)

Date: Tuesday 12th January 2010

Time: 16.53 (21.53 GMT)

Size: shallow focus earthquake -

Depth of 13 km.

7.0 on Richter scale. Aftershocks

between 5.0 and 5.9.

Destructive Plate Boundary: N.

American plate is being subducted

below the Caribbean plate

Physical Causes:

A shallow focus earthquake

The fault line hadn’t moved for

250 years – people were

unprepared

Human Causes: The epicentre of the earthquake

was 16km south west of Port-Au-

Prince

Haiti is the poorest country in the

Western Hemisphere

The buildings in Port-Au-Prince and

other areas of Haiti were in very

poor condition in general and were

not designed or constructed to be

earthquake resistant.

3 Million people live in Port au Prince

with the majority living in slum

conditions after rapid urbanisation.

Haiti only has one airport with one

runway. The control tower was badly

damaged in the earthquake. The

port is also unusable due to damage

Primary Effects: The port was destroyed hampering

aid response

Water supplies & power cut

an estimated three million people

were affected by the quake

between 217,000 and 230,000

people died

an estimated 300,000 injured

an estimated 1,000,000 homeless

250,000 residences and 30,000

commercial buildings had collapsed

or were severely damaged.

Secondary Effects: Communication systems, air, land,

and sea transport facilities,

hospitals, and electrical networks

had been damaged by the

earthquake, which hampered rescue

and aid efforts;

confusion over who was in charge,

air traffic congestion,

Lack of aid & police force caused

violence

Medical treatment was hampered by

lack of power and shortages of

equipment and medical supplies.

A cholera epidemic broke out due to

unclean drinking water in refugee

camps

Short-term Responses: 400,000 water bottles & 300,000

food rations dropped in first 9

days

Bodies buried in mass graves

Aid supplies flown into the

Dominican Republic and taken

across the border by convoy

Huge international aid response

coordinated by the UN

The UK government has sent eight

mobile medical units along with 36

doctors including orthopaedic

specialists, traumatologists,

anaesthetists, and surgeons. In

addition, 39 trucks with canned

food have been dispatched, along

with 10 mobile kitchens and 110

cooks capable of producing 100,000

meals per day.

Long-term Responses:

Estimated that over 1,000 aid

agencies are involved in the

reconstruction

Unrest as little progress appears to

have been made

The Asian Tsunami 2004

A Case Study of a tsunami in a poorer region

Tsunamis are usually caused by earthquakes. The crust moves and the water

displaced forms the wave

As the waves approaches land the wavelength decreases while the height

increases

Background info:

26 Dec. 2004

The highest wave to come

ashore was 25m

Areas worst affected included

Sri Lanka, Indonesia (especially

Sumatra) & Thailand

Physical Causes:

USGS recorded 9.1 on Richter

Scale

Destructive plate boundary –

the Indo-Australian is being

subducted below the Eurasian

plate

Human Causes: High density of population on

coastal plains

Poor construction of buildings due

to low level of development within

the region

No early warning system

Primary Effects: Over 220,000 died

650,000 were seriously injured

2 million made homeless

1,500 settlements completely

destroyed in Banda Aceh alone

Secondary Effects: Tourism affected in the region

Coastal fisheries were affected

and took time to recover

Subsistence farmers and small

businesses were wiped out

Short-term Responses: Bodies were buried in mass graves

The army was mobilised

Huge international aid effort began

– water purification tablets, food,

sheeting for tents etc.

Uk’s gov promised £75million

following £100million raised by the

public

Long-term Responses:

The Indian Ocean Tsunami warning

system was set up in June 2006

Tsunami response plans now in place

in the region

Managing tectonic hazards – prediction, protection & preparation

It's not possible to prevent earthquakes and volcanic eruptions. However, careful

management of these hazards can minimise the damage that they cause. Prediction

is the most important aspect of this, as this gives people time to evacuate the

area and make preparations for the event.

Predicting and preparing for earthquakes

Earthquakes are not as easy to predict as volcanic eruptions.

Prediction

Laser beams can be used to detect plate movement.

A seismometer is used to pick up the vibrations in the Earth's crust. An increase in

vibrations may indicate a possible earthquake.

Radon gas escapes from cracks in the Earth's crust. Levels of radon gas can be

monitored - a sudden increase may suggest an earthquake.

The behaviour of wildlife can give clues

Many of the prediction techniques used to monitor earthquakes are not 100% reliable.

Planning and preparing for an earthquake is therefore very important.

Preparation

People living in earthquake zones need to know what they should do in the event

of training people my involve holding earthquake drills and educating people via

TV or radio.

People may put together emergency kits and store them in their homes. An

emergency kit may include first-aid items, blankets and tinned food.

Protection

Earthquake proof buildings have been constructed in many major cities, e.g. The

Transamerica Pyramid in San Francisco. Buildings such as this are designed to

absorb the energy of an earthquake and to withstand the movement of the

Earth.

Roads and bridges can also be designed to withstand the power of earthquakes.