Eyjafjallajöku

ll April 2010, Iceland.

The Eyjafjallajökull volcano

What’s it look like?

There it is! A shield volcano!

Where is it?

Volcano location

The wider landscape of

Eyjafjallajökull ….

What were the effects?

• Volcanic eruptions are not uncommon in Iceland – one occurs every five or so years but in April 2010 the largest eruption of Eyjafjallajökull in history occurred.

• With wind direction blowing southerly, the ash cloud spread into northern Europe causing some 100,000 flights to be cancelled and some 7 million people to be stranded.

• Although the volcano actually started erupting in late March 2010, on April the 14th it started giving out huge amounts of ash into the atmosphere (some scientists estimate 140 million cubic metres).

• Scientists are particularly worried because Eyjafjallajökull shares a magma chamber with its nearby sister volcano Katla, which historically has always erupted soon after Eyjafjallajökull.

• As Katla is much bigger than Eyjafjallajökull it has the potential to do huge amounts of damage…luckily it’s not gone off…yet.

• But luckily scientists are keeping an eye on it and it is one of the most monitored volcanoes in the world now.

Roads washed away Total loses to Iceland of £80million Local water supplies were contaminated

with fluoride

100,000 flights cancelled over 8 days Sporting events were cancelled or affected

due to cancelled flights

Eyjafjallajökull has become a new Icelandic

tourist attraction with its own visitors

centre giving a boost to tourism.

It felt like day turned to night due to the

ash blocking out the sun

A Jökulhlaup or GLOF (glacial lake outburst

flood) was caused when the glacier on top

of the volcano melted

Rocks given out by the volcano can be used

for building

Homes and roads damaged and services

(like schools!) disrupted

Lava and ash are rich in nutrients making

the soils in volcanic areas very fertile and

good for agricultural use

Crops were damaged by ash and unable to

be grow

Rescuers wore face masks to prevent them

choking on the clouds of ash

Industries were affected by a lack of

imported raw materials for example fresh

food imports stopped.

The Jökulhlaup caused bridges to become

warped and collapse

Jewellery has been created from the ash

given out and is now a big hit with tourists.

Roads were reconstructed with bridges

being strengthened and raised higher.

The temperature of the nearby river rose

to between 50°C and 60°C killing fish

within the river.

Local flood defences needed rebuilding 500 people were evacuated from homes

and hotels nearby

Aircraft now are able to fly through much

thicker ash clouds than in 2010.

The mountain and glacier and now one of

the most monitored sites in Europe.

Other countries exporting in to, and

around, northern Europe were affected –

for example Kenya had to throw away 10

million flowers that were due to be

exported to Europe, while Italy lost

$14million per day as it was unable to

export anything.

The cost to airlines was well over $1.7

billion

Over to you…

1. Complete the hexagon revision sheet for

Eyjafjallajökull.

2. Draw a diagram of what a shield volcano looks like

3. Explain how a shield volcano is different to a

composite volcano.

Eyjafjallajökull

Causes Details / Facts

Primary Effects

Secondary Effects

Responses

Location

Supervolcanoes

• Supervolcanoes are smaller in number, there’s only

7 that have been discovered, as shown in the map

below, but much bigger in terms of size and impact.

• They are located mostly on destructive plate

boundaries, but are

also located in hot

spots – areas where

magma rises up in

cracks in the mantle.

How Supervolcanoes are created

Where is Yellowstone?

• Yellowstone National Park is home to a supervolcano

which last erupted 640,000+ years ago. Some

scientists believe that this last eruption triggered an

ice age.

• The Yellowstone Caldera sits on a hotspot

underneath the North American Plate. 3 eruptions

have occurred in the last 2m years – meaning (some

scientists believe) it is due to erupt soon

(geologically speaking that could by anytime from

now to the next couple of thousands of years).

• The magma chamber is 80km long, 40km wide and

8km deep. If it erupts it would eject 5,000km³ of

material (5x the minimum size for a supervolcano).

• There are signs of increasing activity within the

caldera – the geysers are becoming more active and

the ground has risen 70cms in places. However no-

one knows if this is just part of the natural cycle.

If it erupts It is predicted

that if Yellowstone erupts

then: • 10,000km² of land would be blasted away.

• 87,000 people would die – some from their injuries in the blast, others from the effects of lack of food and water. 1 in 3 people affected by the ash would die.

• 15cms of ash would cover buildings within 1,000km.

• The ash would affect transport so there would be no planes.

• Electricity and water supplies – major impact on our ability to survive in the USA in particular but ash would have a more widespread effect eg UK.

If it erupts It is predicted

that if Yellowstone erupts

then: • Lahars would form where the ash mixes with water and would

flow across the land and then set like concrete destroying farmland and making towns uninhabitable.

• The ash would reach the UK after 5 days and affect us here.

• Global climates would change because of the ash and gases ejected into the atmosphere. Temperatures are likely to fall by 12-15°C.

• Parts of Europe would see constant snow cover for 3 years. Monsoon rains would fail affecting Asia.

• Crops would fail causing food shortages - it is estimated that 40% of the global population would face severe shortages. There would be loss of plant and animal species.

Over to you…

1. Describe the distribution (location!) of

supervolcanoes.

2. Explain in no more than 50 words how a

Supervolcano is formed.

3. Complete the revision sheet for Yellowstone

National Park

Yellowstone Impacts

Short Term Impacts Long Term Impacts Local / Regional Impacts National / International Impacts

Where is Haiti?

Gulf of Mexico

Pacific

Atlantic

Caribbean

Mexico

Belize

Guatemala

Columbia Venezuela

Guyana

French Guiana

Cuba

Jamaica Dominican Republic

Key Info

Haiti

Main Location Port-au-Prince

Date, time 12/01/2010, 16:53pm

Magnitude 7.0

Distance of epicentre from main location 13km South West

Focus 13km

Summary Statistics

316,000 people killed, 300,000 injured, 1.3 million

displaced, 97,294 houses destroyed and 188,383

damaged.

Haiti Info

Haiti shares the island

Hispaniola with the Dominican

Republic in the Caribbean. The

Haiti earthquake was caused

by the North American Plate

sliding past the Caribbean

Plate at a conservative plate

margin.

Both the North American plate

and the Caribbean plate move

in the same direction, but one

moves faster than the

other. This causes pressure to

build up.

The friction between the two

tectonic plates eventually

released causing a magnitude

7 earthquake on the Richter

Scale with an epicentre 16 kms

south west of Port-au-Prince

and a shallow focus of 5 miles.

Haiti was struck by an

earthquake 16:53 (4:53pm)

local time on Tuesday 12

January 2010. At the time

there were 3 million people

living in the capital city Port-

au-Prince. Most people lived in

slums.

The earthquake struck in a

densely populated area killing

250,000 people and 1.3 million

people were made

homeless. 3 million people

were affected by the

earthquake.

250,000 homes and 30,000

other buildings, including the

President’s Palace and 60% of

government buildings, were

either destroyed or badly

damaged.

The estimated cost of damage

was $14 billion. Transport and

communication links were also

badly damaged by the

earthquake

Hospitals (50+) and schools

(1,300+) were badly damaged,

as was the airport’s control

tower

The main prison was destroyed

and 4,000 inmates escaped

1 in 5 people (20%) lost their

jobs because so many buildings

were destroyed. Haiti’s largest

industry, clothing was one of

the worst affected

The large number of deaths

meant that hospitals and

morgues became full and

bodies then had to be piled up

on the streets

The large number of bodies left

lining the streets meant that

diseases, especially cholera,

became a serious problem.

It was difficult getting aid into

the area because of the

damage to the airport and

generally poor management of

the situation. Aid was left at

the airport and the port was

also badly damaged.

People were squashed into

shanty towns or onto the

streets because their homes

had been destroyed leading to

poor sanitation and health, and

looting became a real problem

$100 million in aid given by the

USA and $330 million by the

European Union. 1 million

people had to live in temporary

camps. 600,000 people moved

away from their homes and to

countryside areas in Haiti.

4.3 million people provided

with food rations in the weeks

following the earthquake

Over 115,000 tents had to be

provided for people to live in.

There were many internally

displaced people (IDP).

Lack of immediate aid through

poor planning, management

and access meant that people

had to try and rescue each

other

Medical teams treated people

in make shift hospitals

organised mainly by the red

cross. Many people had to try

and dig out survivors with their

hands.

After 1 year re-building of

homes and services had begun

but it is believed there are still

1,300 camps full of people

without homes.

Cash for work programs have

been introduced; paying

Haitian people to rebuild and

clear away rubble.

Where is New Zealand?

What type of plate boundary is

it on?

• But some parts of the plate are moving away from each other too – so it’s on a destructive AND constructive plate boundary.

What was it like?

Over to you

1. Separately describe the location of both Haiti and

New Zealand.

2. Explain what type of plate boundary they are on.

3. Complete the revision spider diagram handouts.

a) Highlight in one colour the similarities between the two

earthquakes.

b) Highlight in a different colour the differences between

the two earthquakes.

Haiti

Causes

Responses

Primary Effects

Secondary Effects

New

Zealand

The structure of the Earth

• The crust is where we live and it’s

divided into seven major tectonic

plates plus about 40 smaller

ones.

• There are two different types of

crust – continental crust and

oceanic crust which have

different characteristics.

• Tectonic plates float on the semi molten rock of the asthenosphere, on average the plates move at about 5cms a year in the direction of the convection currents below them in the mantle.

• Convection currents are the movement of the heated up mantle away from the core before then cooling and sinking again.

• Plate margins or boundaries are where tectonic plates meet or pull apart because of these convection currents.

• The mantle has the hottest rock when it is nearest to the core (5,000°C). It is coolest near to the surface but even then the rock is semi molten here - just underneath the crust in the area. This is known as the asthenosphere.

• The area heating all of these up is the core - a dense area made up of rocks containing iron and nickel. The inner core is solid and has a temperature of 6,000°C, as hot as the surface of the sun.

• The convection currents are created by the heat of the outer core – about 5,000°C.

Oceanic Crust Vs

• Oceanic Crust is:

– Newer – most is less than 200

million years old

– Denser – so therefore can

sink

– Can be renewed and

destroyed

• Continental Crust is:

– Older – most is over 1,500

million years old.

– Less dense – so cannot sink

– Cannot be renewed or

destroyed

Continental Crust

Conservative

• At conservative plate margins two plates are sliding past each other in slightly different directions and at slightly different speeds.

• They do not move smoothly and tend to get stuck.

• Pressure builds up along the fault until one plate jerks past the other as the pressure is released – an earthquake.

• The movement has caused the land to become ridged and crumpled.

• There is no volcanic activity because land is neither being created or destroyed.

Constructive

• Constructive plate boundaries are usually found at two oceanic crusts that are moving apart.

• As the plates move apart the gap in the seafloor between them is filled with magma rising up from the mantle below. This creates an underwater volcanic ridge.

• An example of this is the Atlantic Ocean which is getting wider as the seafloor is spreading.

• Sometimes the volcanoes grow high enough to reach the surface and so create volcanic islands like Iceland. It too is growing wider as magma fills in the gap as the plates move apart.

• Shield volcanoes are created here.

Collision

• At collision margins two continental crusts are forced together.

• Neither can be destroyed so the rocks between them are forced upwards under huge pressure.

• It is this forcing upwards that can cause mountain ranges and large earthquakes such as the 2005 Pakistan earthquake.

Destructive

• At destructive plate margins two plates are

moving together – the oceanic and continental

crust meet.

• Where this happens the oceanic crust which is

denser than the continental crust is forced to

sink under the continental plate.

• The oceanic crust is pushed down (subducted)

into the mantle in a place called the subduction

zone.

• The oceanic plate does not slide smoothly under

the continental plate. It moves in a series of

jerks because of friction and so there is a build

up of pressure in the subduction zone.

• An earthquake is caused when this pressure is

released all of a sudden. They can be very high

magnitude.

Destructive

• Pressure builds up in the magma

which will escape through any lines

or cracks of weakness in rocks of

the continental crust. When it comes

to the surface it erupts as a volcano.

• The most common type of volcano

on a destructive margin is a

composite volcanoes which are very

explosive because the lava is acidic

and contains water and gases.

• A deep ocean and fold mountains

are created here.

Collision margin: Two continental

plates collide, they are both the same

density and so they crash and the

land buckles into fold mountains. The

Indo-Australian plate is colliding with

the Eurasian plate and has formed

the Himalayas.

Destructive margin:Subduction

Nazca plate (oceanic crust) is

being subducted under the South

American plate (continental

crust).

Constructive margin: Mid Atlantic Ridge is

marked by an underwater chain of volcanoes

and fissures (cracks) where the North

American plate is being pulled away from the

Eurasian plate. Iceland has been formed

where these volcanoes have built up to the

surface.

Conservative margin: The

North American plate and the

Pacific plate are sliding past

each other. This is the San

Andreas Fault.

Over to you…

1. Draw a diagram of the structure of the earth.

Annotate all around it what each area is like.

2. Create a table of what the differences between

oceanic and continental crust are. Give at least 3

reasons why / when these become important.

3. Explain in no more than 50 words EACH how shield

volcanoes, composite volcanoes and earthquakes

are formed.

What causes a tsunami?

• A tsunami (a Japanese word meaning harbour wave)

is a massive movement of water caused often by

earthquakes that take place underwater or volcanic

eruptions.

• It can also be created by landslides into water, or

underwater explosions.

• The earthquake (at a destructive or conservative

plate boundary) sends out a huge amount of energy

through the sea; and at a destructive plate boundary

– the plates themselves move; this causes the water

to move out in all directions.

• These waves move out increasing in length to

around 200km and speed, up to 800km a hour but

start off relatively small in height, at about 1 metre

high.

• As the waves near the coast and the sea shallows

the amount of water in contact with the base of the

sea the amount of friction increases and the waves

slow down in speed to about 80km an hour.

• As the waves slow down, more and more of them

bunch up together and raise up in height – from

anywhere between 10m and 30m – this gives the

impression that the sea is retreating, when in reality

the water is being pulled back to add to the giant

tsunami wave.

Our case study…

• Is the 2004 Boxing Day Tsunami.

• It was caused by an earthquake measuring between 9.1 and 9.3 on the Richter scale

• It killed over 230,000 people in fourteen countries.

• It was to be the fifth deadliest earthquake in history.

http://upload.wikimedia.org/wikipedia/commons/8/89/2004_Indian_Ocean_earthquake_-_affected_countries.png

• Scientists have predicted that the power unleashed

by the wave was similar to that of 1500 atomic bombs

being released.

• It was made worse was the fact that countries in the

Indian Ocean had no tsunami warning system (unlike

places like Hawaii for example) as it was too

expensive for them to afford.

• Waves reached a maximum height of 24 metres in

Ache province in Indonesia,

the worse hit of all the countries.

• On average the height of the tsunami waves at

their worse were around 10m.

http://upload.wikimedia.org/wikipedia/commons/5/57/Tsunami_size_scale_26Dec2004.png

Over to you…

1. Describe where the Boxing Day Tsunami hit.

2. Explain what caused the Boxing Day Tsunami and

why it was so bad (hint – link to development here)

3. Complete the hexagon revision sheet.

Boxing Day Tsunami

Causes Details / Facts

Primary Effects

Secondary Effects

Responses

Location

Glacial landforms

• Are made up of processes including:

• Accumulation – when snow gathers at the top of a mountain and fails to melt. Over time through compression this will become glacial ice.

• Compression – when snow is pushed down under the weight of fresh snow having fallen on top of it to create glacial ice.

• Freeze Thaw - Water in a crack freezes and expands. This puts pressure on surrounding rock. It thaws and contracts repeatedly to weaken joints in the rock. The rock eventually breaks off.

• Abrasion - Abrasion is the process where rock fragments in the ice grind against the rock over which the ice is moving (like rough sandpaper) wearing away the land.

• Plucking - Plucking is where meltwater at the base of the glacier freezes on the rock surface. As the glacier moves forward it extracts pieces from the rock surface.

Types of Moraine

• Lateral moraine is deposited on both sides of a valley.

• Medial moraine is formed when two glaciers meet and is deposited in the centre (middle) of a valley.

• Ground moraine is deposited unevenly across a valley floor as a glacier retreats.

• Terminal moraine is deposited at the snout (front) of a glacier and marks the furthest point reached.

• name these?

Can you

name

and explain

these?

U Shaped Valleys /

Glacial Troughs

• Are a glacial landform of erosion.

• Created over thousands of years.

• Found in Wales and the Lake District.

U Shaped Valleys – Before the

Ice Age

U Shaped Valleys – During the

Ice Age

U Shaped Valleys – After the

Ice Age

Corrie

Arm chair shaped hollow that snow and ice accumulate in, carved by a glacier

Tarn formed in the deepest part of the corrie as it was scooped out by erosion (abrasion)

Steep back wall caused by freeze-thaw and plucking

Rock lip at the edge of the corrie formed by deposits as the glacier rotated out of the basin

Pyramidal Peak: Steep mountain formed as three corries retreat backwards

Corrie back-wall steepened by freeze-thaw and abrasion

Pyramidal Peak

Ribbon Lake: Long, thin lake

Area of softer rock found in the middle of two areas of harder rock

As the glacier melted water got stuck in areas previously eroded by abrasion.

Arete

Sharp knife edged ridge between TWO corries.

Formed as two corries are eroded and weathered backwards.

Corrie

An arm chair shaped hollow widened and deepened by a glacier.

Steep back wall created by freeze-thaw and plucking

Named example

Striding Edge on Helvellyn in the Lake District

A hanging valley is a smaller side valley left 'hanging' above the main u-shaped valley.

A waterfall is often seen as the smaller valley meets the bigger one

The bigger valley is caused by a larger glacier eroding down further.

Where the smaller hanging valley has been cut is known as a truncated spur.

Drumlins

• Drumlins are formed of glacial till – the name

given to moraine after the ice has melted.

• They are long features that can reach a

kilometre or more in length, 500m or so in

width and over 50m in height.

Drumlins form when…

• Moraine collects in front of an immovable object

before spilling over the top and down behind the

immovable object.

• The glacier shapes and moulds the drumlin with a

blunt end facing up valley and a pointed tail end

facing down the valley, in the direction that the ice

travelled.

• When the glacier melts a drumlin is left behind.

• An erratic is a boulder

that is different to the

bedrock upon which it

is sitting.

• They have been

transported and

deposited by a glacier.

• Therefore erratics are

useful indicators of

patterns of former ice

flow.

Over to you…

1. Draw, define and (where necessary) explain the

different processes that take place in glacial

environments.

2. Choose three different landforms of erosion and

explain how they are created.

3. Choose one landform of deposition and explain

how it is created.

A Retreating Glacier – The

Rhone Glacier

• Our example is the Rhone Glacier in Switzerland, it’s

in the south of the country and is one of a number of

glaciers in Switzerland. It is also a good example of

one that is retreating quickly, and the potential

impact of this on the surrounding area.

• Since 1860 the thickness of the Rhone glacier has

reduced by 34m.

• The length of the glacier changes over the course of

the year (with it retreating in the summer, and

advancing in the winter) shown by the red line.

• The overall length of the glacier (shown by the green

line) shows a significant reduction, around 1.2km

has been lost.

• The fastest reduction has been from 1950 onwards

(shown by the steeper, declining green line).

Year

Len

gth

of

Gla

cier

(M

etre

s)

//upload.wikimedia.org/wikipedia/commons/4/48/Rhone_glacier_stats.svg

• Glacial retreat is particularly important in

Switzerland, for starters if it continues there is the

potential in the short term for catastrophic flooding,

while long term the tourist industry could suffer a

significant drop.

• The glacier is also hugely important for

Switzerland’s water and electricity supply, as during

the summer much of the melted ice is either treated

and used for drinking water, or used to produce

around half of Switzerland’s energy.

• Scientists have suggested that glacial retreat has been causes by the warming up of the earth, with an increase in temperature of 0.74°C since 1900.

• This may be in part may be linked to the increased use of fossil fuels (like oil and coal) or the increased emissions (releasing of) carbon dioxide in the atmosphere, which has caused a greenhouse effect, and raised temperatures in the world.

• As a result it is too warm for snow to fall, instead falling as rain, meaning a lack of glacial ice being created, and the chance for flooding increased.

Over to you…

1. Describe the location of the Rhone glacier.

2. Describe why it is important to the area.

3. Explain how you know it is retreating referring to

specific evidence / examples.

4. Explain the causes of its retreat.

Chamonix and the Alps

• Are a good example of tourism in a mountainous

area (for Ice on the land) and uses of a fold mountain

(for Restless Earth).

• One BIG case study – two uses.

• Result eh?

The Alps!

Over to you…

1. How are the Alps used? Make a spider diagram of all the different uses on some A3 paper – use different colours to show each of the different uses and add detail from each use.

2. What can tourists do in Chamonix? Use the information sheets to help you.

3. What problems does living in the Alps have?

4. How have people overcome problems with living in mountainous areas?