Chapter 1 restless earth

Mr. Walsh - @Examrevision4u


Unit 1 Unit

Content:Restless Earth

Assessment:Junior Cert


Cht Cht

Content:Restless Earth

Assessment:Junior Cert

1Mr. Walsh - @Examrevision4u

Restless EarthHeading:

Tuesday 2 May 2023Date:

LessonObjectives: 1Ch

tLesson 002

Inside the Earth!Learning Objectives: 1.To know that the earth is made from layers and be able to describe each of them.2.To use creative writing and geographical vocab to describe a journey to the centre of the earth

CW Tuesday 2 May 2023

Facts about earth

1. More than 7 billion live on earth.2. 2/3 of the earths surface is water.3. 1/8 of the earths surface is deserts.4. 1/10 of the earths surface is mountains.5. ¼ of the earths surface is forests.

Imagine you were taking a journey to the centre of the earth.......

What would you come across?

Journey to the centre of the

earth!

www.virginvolcanic.com

Only 500 people have been to space, only three people have been to the bottom of the

ocean, but no one has ever attempted to journey to the core of an active volcano.

Until now!!!

http://www.virginvolcanic.com/

What’s the connection?

What’s the connection?

Crust

Mantle

Outer Core

Inner Core

This is the layer we live on!

This is the hottest layer. It is solid

This layer is liquid and made of iron and nickel.

This is the largest layer. My rock is called magma.

10-60km thick

The temperature here is around 5500 ˚C

The exact thickness of the varies- it is

thinner where there are oceans, and

thicker where there are mountains

Task: 1.Shade in the four earth layer boxes below different colours.2.Draw lines from these 4 boxes to the correct place on the earth.3.Using the information page, shade in the remaining boxes on the left so they match the correct layer of the earth.

Challenge:If nothing has ever been to

the centre of the earth – how do we know what its

like?

Crust

Mantle

Outer Core

Inner Core

This is the layer we live on!

This is the hottest layer. It is solid

This layer is liquid and made of iron and nickel.

This is the largest layer. My rock is called magma.

10-60km thick

The temperature here is around 5000 ˚C

The exact thickness of the varies- it is

thinner where there are oceans, and

thicker where there are mountains

Task: 1.Shade in the four earth layer boxes below different colours.2.Draw lines from these 4 boxes to the correct place on the earth.3.Using the information page, shade in the remaining boxes on the left so they match the correct layer of the earth.

Challenge:If nothing has ever been to

the centre of the earth – how do we know what its

like?

Where am I?

Red: Inner Core

Orange: Crust

Green: Mantle

Where am I?

Inner Core

Outer Core

Mantle

I am mainly iron, mixed with a little

nickel.

I am a solid ball

Where am I?

Inner Core

Mantle

Outer Core

I consist of iron and nickel.

I am a liquid

Where am I?

Inner Core

Mantle

Crust

I am the thickest layer, forming about

half of the earth

My rock is in a molten state.

How did the layers form?• Some time after the earth

formed, it got so hot that everything inside melted!

• What do you think happened to the heavier substances?– The heavier substances such

as iron and nickel in the liquid sank.

• What happened to the lighter substances?

• They rose to the surface

Convection Currents form when heat from the core creates waves or currents that pass through the mantle

Outcome Check!A – You can use a wide range of evidence to explain why each layer of the earth changes.

B – you can describe the differences between each layer of the earth and start to explain the differences.

Imagine you won a seat on the ‘Virgin Volcanic’ for a journey from the surface of the Earth all the way to the centre.

Write a storyboard to describe and explain what you see.

Describe what each layer looks like (C)Explain how each layer is different (B)Explain why the layers are different (A) You will need to use the information you have collected this lesson and the word mat Quick Check!

Explain means....?Use your Textbook page 3

WORD MATESSENTIAL WORDS

CrustMantle

Outer CoreInner Core

GEO WORDS

KmIronSolidEarthNickelLiquid

HottestTemperature

Imagine you won a seat on the ‘Virgin Volcanic’ for a journey from the surface of the Earth all the

way to the centre.

Write a storyboard to describe and explain what you see.

Describe what each layer looks like (L4)

Explain how each layer is different (L5)

Explain why the layers are different (L6)

ADJECTIVESDangerousHazardous

HottestRiskyDarkLight

SwelteringBubblesShaking

LoudExciting

MesmerisingUniqueFloatingThrilling

Vast

Challenge WordsConvection CurrentGravitational Pull

AFL Feedback Sheet – Journey to the Centre of the Earth

Ticks mean you have done this well Ts mean this is your target to improve.

D – Use key terms such as crust, mantle, outer core, inner core. C – Use descriptive terminology (e.g. solid, liquid) to describe each layer. B - Explain the differences in the layers, e.g. “The inner core is made of very dense material, this is because it sank when the earth was created as it was heavy.” A – Use evidence e.g. “The crust is only 8-65km thick.” What adaptations would your vehicle require to ensure you survive this journey?Check spelling of ........................ is correct. Make sure all sentences start with a capital letter. Correct this.Key words do not begin with a capital e.g. mantle, biome, ecosystem and desert. Correct this.

The journey to the centre of the _______ started with great excitement.

We started on the outer layer which we live on, called the C_____. This layer is thin, at about _______km in thickness.

What level am I?

We started our journey in to the boiled egg by cracking in to the shell. The shell was thin (1mm thick) but brittle. Once in, the giant drill we were in, burrowed down in to the egg white. This was the thickest layer (10mm). The drill swayed side to side and it started to get warm. We approached the outer yoke and we started to slow down. Light came rushing through the windows so we knew we were close. The yoke was dense and difficult to get through…..

We started our journey in to the boiled egg by cracking in to the shell. The shell was thin but brittle. Once in, the giant drill we were in, burrowed down in to the egg white. This was the thickest layer. The drill swayed side to side and it started to get warm. We approached the outer yoke and we started to slow down. Light came rushing through the windows so we knew we were close.

We started our journey in to the boiled egg by cracking in to the shell. The shell was thin (1mm thick) but brittle in order to protect the inside. Once in, the giant drill we were in, burrowed down in to the egg white. This was the thickest layer (10mm). We approached the outer yoke and we started to slow down. Light came rushing through the windows so we knew we were close. The yoke was dense, made of heavy matter as it had sunk to the middle of the egg.

Journey to the Centre of the Earth!L4 - Describe what each layer looks like. L5 - Explain how each layer is different. L6 - Explain why the layers are different.

The journey to the centre of the _______ started with great excitement.

We started on the outer layer which we live on, called the C_____. This layer is thin, at about _______km in thickness.

We passed through concrete, then soil and passed water pipes. The next layer is called the _________.

This layer is much softer and we could easily float down. This was the __________ layer at about 2900km!

Soon we saw the bright light of the outer _______. This layer is made up of mainly ______ mixed with nickel.

Finally we made it to the _________ core. This was truly the centre of the Earth! What a journey.

Journey to the Centre of the EarthMissing words: Core Iron Inner Thickest Mantle Crust 8-65 Earth

Self/Peer Assess

• Count up how many points you have from the word mat.– Bold key words = 2 points– Other key words = 1 point

• Pass your work to your partner, what level did they give you?

Level 4 = Describe what each layer looks like. Level 5 = Explain how each layer is different. Level 6 = Explain why the layers are different.

Where and why do we get earthquakes and volcanoes?

Learning objectives: To know where earthquakes and volcanoes occur.To know 4 plate boundaries.

Tuesday 2 May 2023

What are these school children doing?What has this to do with plate tectonics?

September 1st National Earthquake Drill Day, Japan

Starter – where do we get earthquakes and volcanoes? Why?

= volcano = earthquakes

To complete the next task, we need to check some key words.

Continental crust Hot molten rock from the mantle that reaches the surface.

Oceanic crust The thick crust which has land on it. 25 – 70 km thick. It is less dense.

Magma The thin crust under the oceans. It is thin but dense (heavy).CHALLENGE: What would happen if a

continental plate and an oceanic plate collided?

Explain the causes of earthquakes and volcanoes

Independent Enquirers Using your book complete the following worksheet.

EXT – Hot spots (you can use your internet for this only!!)

10 minutes

At a constructive plate boundary, two plates move apart.

As the two plates move apart, magma rises up to fill the gap. This causes volcanoes. However, since the magma can escape easily at the surface the volcano does not erupt with much force.

Small earthquakes are also found at constructive boundaries.

An example of a constructive boundary is the Mid-Atlantic Ridge (this is between Africa and South America, at the bottom of the ocean).

Constructive Plate Boundary

A destructive plate boundary is found where a continental plate meets an oceanic plate.

The oceanic plate descends under the continental plate because it is denser. As the plate descends it starts to melt due to the friction caused by the movement between the plates. This melted plate is now hot, liquid rock (magma). The magma rises through the gaps in the continental plate. If it reaches the surface, the liquid rock forms a volcano. An example is the Philippines, which suffers lots of earthquakes and volcanoes

Destructive Plate Boundary

Conservative plate boundaries exist where two plates do not directly collide but slide past each other along a fault (weakness).

No volcanoes are found along these plate boundaries, but earthquakes do occur.

An example of such a boundary is the San Andreas Fault in California.

Conservative Plate Boundary

EXTENSION:Hot Spots

A hotspot is a region of high volcanic activity that is not located on a tectonic plate boundary.

About 30 km below the surface of the Earth is the mantle, a region where temperatures can reach thousands of degrees Celsius. But that’s under the continents. Underneath the oceans, the mantle is only 10 km down or less. Molten rock can seep out of the mantle and form vast magma chambers beneath the Earth’s crust. This magma finds its way to the surface, creating volcanoes. The magma comes from a plume.

As the plates move over the plume, a chain of volcanoes forms.

Plate movements

Times up

Green pen improvements

At a constructive plate boundary, two plates move apart. As the two plates move apart, magma rises up to fill the gap. This causes volcanoes. However, since the magma can escape easily at the surface the volcano does not erupt with much force.

Earthquakes are also found at constructive boundaries.

An example of a constructive boundary is the Mid-Atlantic Ridge. (this is between South America and Africa)

1) Constructive Plate Boundary

GREEN PEN IMPROVEMENTS

A destructive plate boundary is found where a continental plate meets an oceanic plate.

The oceanic plate descends under the continental plate because it is denser. As the plate descends it starts to melt due to the friction caused by the movement between the plates. This melted plate is now hot, liquid rock (magma). The magma rises through the gaps in the continental plate. If it reaches the surface, the liquid rock forms a volcano.

2) Destructive Plate Boundary


Conservative plate boundaries exist where two plates do not directly collide but slide past each other along a fault (weakness).

No volcanoes are found along these plate boundaries, but earthquakes do occur.

An example of such a boundary is the San Andreas Fault in California.

3) Conservative Plate Boundary


Hot Spots

A hotspot is a region of high volcanic activity that is not located on a tectonic plate boundary.

About 30 km below the surface of the Earth is the mantle, a region where temperatures can reach thousands of degrees Celsius. But that’s under the continents. Underneath the oceans, the mantle is only 10 km down or less. Molten rock can seep out of the mantle and form vast magma chambers beneath the Earth’s crust. This magma finds its way to the surface, creating volcanoes. The magma comes from a plume.

As the plates move over the plume, a chain of volcanoes forms.

Plate movementsGREEN PEN IMPROVEMENTS

Quick Check!

When 2 plates move apart it is called a ...?

Which plate boundary have earthquakes but no volcanoes?

A plate boundary is...

The Mid-Atlantic Ridge is an example of ...?

Where the edge of 2 plates meet

Where land ends and you can’t go any further

Destructive boundary

Constructive boundary

Destructive Conservative

New land created at a constructive plate boundary

2 plates colliding

Exam style questionExplain why destructive plate boundaries have both earthquakes and volcanoes

Key WordsContinentalOceanicHeavyLightSinksSubductionFrictionEarthquakesMagmaPressureVolcano

Oceanic crust

mantle

continental crust

Magmarising

7 mins

Friction causes earthquakes

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How many key words have been used:

To improve I could:

Exam style question

Explain why destructive plate boundaries have both earthquakes and volcanoes

Key WordsContinentalOceanicHeavyLightSinksSubductionFrictionEarthquakesMagmaPressureVolcano

Oceanic crust

mantle

continental crust

Magmarising

7 mins

Friction causes earthquakes

At destructive plates boundaries earthquakes occur because .............................................................................

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Volcanoes happen here because ........................................

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How many key words have been used:

To improve I could:

AFL Feedback SheetTicks mean you have done this well Ts mean

this is your target to improve.Level 4I have described where volcanoes occur Level 5I have explained why volcanoes occur at destructive plate boundaries using 5 key wordsLevel 6I have explained why volcanoes occur at destructive plate boundaries using linked explanations and all key words Level 7I have used a named example of a volcano/earthquake in my answer. I have named the plates and dates of the eruptions/vibrationsQuality of written communication Check spelling of ........................ is correct. There may be an SP shows where this is an issue. Correct punctuation error/ avoid this in future see P Make sure all place names and sentences start with a capital letter, e.g. The Amazon, Sahara, Brazil, Harrow. Correct this, there may be a C to help you locate this. FS = write in full sentences // = new paragraph

Peer Assessment

Homework:

Complete your targets to improve your level

Green Pen to show improvements


this is your target to improve.Level 4I have described where volcanoes occur Level 5I have explained why volcanoes occur at destructive plate boundaries using 5 key wordsLevel 6I have explained why volcanoes occur at destructive plate boundaries using linked explanations and all key words Level 7I have used a named example of a volcano/ earthquake in my answer. I have named the plates and dates of the eruptions/vibrations Quality of written communication Check spelling of ........................ is correct. There may be an SP shows where this is an issue. Correct punctuation error/ avoid this in future see P Make sure all place names and sentences start with a capital letter, e.g. The Amazon, Sahara, Brazil, Harrow. Correct this, there may be a C to help you locate this. FS = write in full sentences // = new paragraph


this is your target to improve.Level 4I have described where volcanoes occur Level 5I have explained why volcanoes occur at destructive plate boundaries using 5 key wordsLevel 6I have explained why volcanoes occur at destructive plate boundaries using linked explanations and all key words Level 7I have used a named example of a volcano/ earthquake in my answer. I have named the plates and dates of the eruptions/vibrations Quality of written communication Check spelling of ........................ is correct. There may be an SP shows where this is an issue. Correct punctuation error/ avoid this in future see P Make sure all place names and sentences start with a capital letter, e.g. The Amazon, Sahara, Brazil, Harrow. Correct this, there may be a C to help you locate this. FS = write in full sentences // = new paragraph

The Earth’s Solar SystemHeading:

Tuesday 2 May 2023Date:

LessonObjectives: 1Ch

tLesson 002

The Earth

1. Learn about the solar system.2. Recall the 8 planets in our solar system.

Starter:How many planets can you name in our solar system?

Notes

• The solar system is made up of the sun, 8 planets and their moons.

• Inner planets: close to the sun, solid sphers- Mercury, Venus, Earth, Mars.

• Outer planets: gaseaus spheres with rings- Jupiter, Saturn, Uranus, Neptune.

• Since 2006 pluto is a dwarf planet.• Learn: My very energetic mother just served

us nuggets.

Distance From The Sun57,900,000 km

Diameter4879 km

Temperature167oC

Length of Day59 Earth days

Length of Year88 Earth days

http://apod.nasa.gov/apod/image/0801/mercury03_messenger_big.png


Diameter12,104 km

Temperature464oC

Length of Day243 Earth daysLength of Year

224.7 Earth days

http://apod.nasa.gov/apod/image/0203/venus180hem_magellan_big.jpg


Diameter12,756 km

Temperature15oC

Length of Day24 hours

Length of Year365.25 days

http://upload.wikimedia.org/wikipedia/en/3/33/Full_Sunburst_over_Earth.JPG


Diameter6792 km

Temperature-65oC

Length of Day24.7 hours

Length of Year687 Earth days


Diameter142,984 km

Temperature-110oC


Length of Year11.9 Earth Years

Distance From The Sun1,433,000,000 km

Diameter120,356 km

Temperature-140oC




Diameter51,118 km

Temperature-195oC




Diameter49,528 km

Temperature-200oC


Length of Year163.8 Earth years


Diameter2390 km

Temperature-225oC

Length of Day6.4 Earth daysLength of Year

248.2 Earth years

Structure of a volcanoObjective

To learn about volcanoes 1. MUST be able to understand how volcanoes

form and why

2. SHOULD be able to explain active, dormant and extinct volcanoes

3. COULD think examples of famous volcanoes and earthquakes

Tuesday 2 May 2023

Some new key wordsVolcanoes

- Volcano- Vent- Secondary cone- Lava- Dormant - Eruption- Volcanic dust

- Volcanic ash- Magma chamber- Volcanic gas- Cone- Crater- Active - Extinct

What is a volcano?• A volcano is an opening in the

Earths crust known as a vent. Magma from inside the earth is forced out and erupts as lava, ash, gas, and dust. When these materials are forced through the vent is causes an eruption.

How do volcanoes form?

Volcano erupts

Volcano builds up

Volcano formed

Magma chamber

Main vent

crater

Gas, ash, dust

LavaSecondary cone

Layers of ash and lava cone

Complete page 3 in workbook question 2

Magma chamber

Main vent

crater

Gas, ash, dust

LavaSecondary cone

Layers of ash and lava

Activities:• Complete activity 2 on

p119 - clearly and well labelled.

• For each of the following terms write a definition into your book using page 118 and the glossary: volcano, vent, crater, magma chamber.

• Explain the difference between lava and magma.

Extension: read pg 118 and 119 then answer question 4 into your book

15 minutes

Volcanoes can be either Active, Dormant or Extinct.

Active VolcanoesA volcano which has erupted recently

Dormant VolcanoesA volcano which has erupted in the last 2000 years,but not recently is dormant or asleep.

Extinct VolcanoesA volcano which is unlikely to erupt ever again and is dead or extinct.

Key words

• You and the person sat next to you have just 5 minutes to quietly discuss the key words you wrote down at the start of lesson ready to explain them to the rest of the class.

Test!Time now for a little test. Ten definitions are going to be shown and you have TEN seconds to write down the answer of each.

10 9 8 7 6

5 4 3 2 1

Fumes from the volcano

1

10 9 8 7 6

5 4 3 2 1

The pipe up which the magma comes up from

2

10 9 8 7 6

5 4 3 2 1Molten rock erupting from a volcano

3

10 9 8 7 6

5 4 3 2 1

The top of the volcano

4

10 9 8 7 6

5 4 3 2 1

The shape of the volcano

5

10 9 8 7 6

5 4 3 2 1

Solids from the volcano

6

10 9 8 7 6

5 4 3 2 1

Molten rock before it is erupted

7

10 9 8 7 6

5 4 3 2 1

The area beneath the volcano

8

10 9 8 7 6

5 4 3 2 1

A period of volcanic activity

9

10 9 8 7 6

5 4 3 2 1

A place where lava erupts at the Earth’s surface

10

Answers 1. Volcanic gas / ash2. Main vent3. Lava 4. Crater 5. Cone6. Ash7. Magma 8. Magma chamber9. Eruption10.Volcano

How do we know that the

continents have moved over time?

Why are plate boundaries known as danger zones?

If constructive boundaries create more

crust why isn’t the Earth

getting bigger?

When all the continents were

joined together it was called

Pangaea: what happened to it?

How? Why?

Structure of a volcanoObjective

To learn about volcanoes

MUST be able to understand how volcanoes form and why

SHOULD be able to explain active, dormant and extinct

volcanoesLearn about examples of

famous volcanoes and earthquakes

Tuesday 2 May 2023

Magma chamber

Main vent

crater

Gas, ash, dust

LavaSecondary cone

Layers of ash and lava

cone

Volcanoes can be either Active, Dormant or Extinct.

Active Volcanoes

A volcano which has erupted recently eg. Mount Etna, Mount Vesuvius.

Dormant Volcanoes

A volcano which has erupted in the last 2000 years,but not recently is dormant or asleep.

Extinct Volcanoes

A volcano which is unlikely to erupt ever again and is dead or extinct.

Case Study: Mount St. Helens

Where: Mountain peak in the Rocky Mountains, USA.

When: Spring 1980/ 18th May 1980.Why: Earthquake of magnitude 5.1 happened

10mins before- the entire northside of the mountain was blown off.

Effects: 57 people died. Height of mountain was reduced by 400metres. A new crater, almost 3km wide was created. Mud flows were created from the melted glacial ice and snow.

Earthquakes

Learning objective(s):• To know about different plate boundaries

Learning Outcome:• To use group work to draw and label the different

plate boundaries

What do you already know?

Create a spider diagram or a list that answers the question about what you already know about earthquakes

What do you already know?

Create a spider diagram or a list that answers the question about what you already know about earthquakes

Destructive Plate Boundary

Constructive Plate Boundary

Conservative Plate Boundary

An Earthquake is…The shaking and trembling that results from the movement of rock beneath Earth's surface The movement of Earth's plates produces strong forces that squeeze or pull the rock in the crustThis is an example of stress, a force that acts on rock to change its volume or shape

http://courses.smsu.edu/ejm893f/creative/earthquake/focus-epi.jpg

Measuring EarthquakesThere are at least 20 different types of measures2 of them are the Mercalli scale & Richter scale.Magnitude is a measurement of earthquake strength based on seismic waves and movement along faults

The Richter ScaleThe Richter scale is a rating of the size of seismic waves as measured by a particular type of mechanical seismograph Developed in the 1930’sAll over the world, geologists used this for about 50 yearsElectric seismographs eventually replaced the mechanical ones used in this scaleProvides accurate measurements for small, nearby earthquakesDoes not work for big, far ones

Analyse the following pictures using your source grid

Answer five of the questions!

The 2011 Japan Earthquake and Tsunami

Watch the following documentary on the 2011 Japanese earthquake and

Tsunami

Write five short term effects and five long term effects of the disaster

What one short or long term effect do you think was most

severe and why?

Your task1. Essay: Why did so many people die and were left

homeless in the Japan 2011 Earthquake and Tsunami?

2. Diary extract of a person who survived the disaster. This creative writing piece must include how the earthquake/tsunami affected their life and how the disaster was managed in their area.

3. Display board showing the causes, effects and hazard management techniques of the earthquake/tsunami (has to be detailed, in your own words, NOT just a simple poster)

4. Newspaper article with a catchy headline of your choice.

• Your work MUST include the causes of the earthquake, the impacts of the earthquake/tsunami, and how the government tried to manage the disaster.

Imagine you are the Japanese government –

what changes would you make to prevent this

happening again?

Volcanic Activity

Volcanoes

• In the last section we learned that the outer layer of the earth is called the Crust.

• We also learned that the crust is broken into many different pieces called Plates.

• The plates are constantly moving because of Continental Drift.

• This movement causes the plates to push together, pull apart, or slide past one another.

How do Volcanoes Occur?

• Volcanoes occur when two of the earth’s plates pull apart.

• Remember, beneath the crust the mantle is made from semi-molten (melted) rocks called magma.

• So when a gap occurs in the crust (which happens when two plates pull apart) the magma spills out through the gap.

Lava

• When the magma reaches the surface of the earth it is called lava. This is the reddish liquid you see coming out of a volcano.

The effects of Volcanoes

• When the lava comes out of a volcano it cools and forms into solid rock.

This can result in the formation of,1. Mid Ocean Ridges2. Volcanic Islands3. Volcanic Mountains

Mid-Ocean Ridge• Sometimes volcanoes occur

under the sea.• If two plates pull apart

under the sea the lava rises up to the ocean floor.

• It cools quickly into solid rock as it touches the cold sea water.

• After many eruptions these layers of new rock build up to form mountains under the water.

• A long chain of volcanic mountains under the sea is called a Mid-Ocean Ridge.

The Mid-Atlantic Ridge• Under the Atlantic Ocean

the American plate is pulling apart from the Eurasian and African Plate.

• This is causing underwater volcanic eruptions which has created a long chain of underwater mountains.

• These mountains make up the Mid-Atlantic Ridge.

• Some of the mountains in the chain are so high they stick out of the water and form volcanic islands.

The Mid-Atlantic Ridge

The Mid-Atlantic Ridge

Volcanic Islands

Volcanic Islands

• When underwater volcanoes continually erupt eventually they may grow big enough to stick out of the water.

• They form volcanic islands. Iceland is an example of a volcanic island.

Iceland: A Volcanic Island

• Iceland is a volcanic island which has been formed as a result of underwater volcanic eruptions.

Iceland: A Volcanic Island

Volcanic Mountains• When two plates pull apart a gap

is created. This gap provides a hole which the magma can escape from the mantle. It is called a Vent.

• When the magma cools, along with other materials from the volcano such as mud and ash, they usually form a cone shaped mountain

Volcanoes

Stages in volcanoes

• Volcanoes can be in one of 3 stages,

1. Active2. Dormant3. Extinct

Stages in volcanoes

Active Volcanoes - The volcano is still erupting quite regularly. E.g. Mount Etna, Italy.

Dormant Volcanoes - The volcano has not erupted for a long time but may erupt in the future.

Extinct Volcanoes – The volcano has not erupted in historic times and will not erupt again.

The Pacific Ring of Fire• Many of the world’s major

earthquakes and many of the world’s active volcanoes occur in a zone that encircles the Pacific Ocean.

• This is because many of the world’s major plates meet here. Therefore, at this place the plates are pulling apart, pushing together and sliding past one another.

• This causes earthquakes and volcanoes to occur.

The Pacific Ring of Fire

The Pacific Ring of Fire

Fold Mountains

Mountains formed when two Plates Collide.

Fold Mountains

• Fold mountains are mountains that are made when two of the earth’s plates collide.

• When two plates collide the pressure compresses the rocks, forcing them to buckle and fold. Think of what happens to the bonnet of a car during a crash.

Fold Mountains

Fold Mountains

Evidence of Folding• Scientists have found fossils of dead sea creatures

thousands of metres up in the Andes in South America.

• These creatures lived in the sea, and their remains sank to the ocean floor when they died.

• Their remains were trapped in newly forming rocks which are later pushed up from under the sea when plates collide to make fold mountains.

Ridge and Valley Landscape

• When the two plates collide the crust buckles and folds. This creates a pattern of ridges and valleys.

• The downward part (the valley) is called a syncline.

• The upward part (the ridge) is called an anticline.

Young Fold Mountains• As we know from previous sections, the earth’s

plates are constantly colliding in different parts of the world. These collisions are still increasing the height of some fold mountains today.

• The world’s young fold mountains are already about 30-35 million years old.

• These mountains are called Alpine Fold Mountains. They are very high because they have not been worn down by weathering and erosion.

Alpine Fold Mountains

• There are 4 major mountain ranges formed during the Alpine Folding period. These are,

• 1. The Rockies in North America.• 2. The Andes in South America.• 3. The Alps in Europe.• 4. The Himalayas in Asia.

Where are Fold Mountains Made?

Fold Mountains





Which 2 plates collided to form the Andes?

The Himalayas

The Himalayas

The Himalayas

Which 2 plates collided to make the Himalayas?

Armorican Fold Mountains• Ireland’s fold mountains were formed hundreds of millions

of years ago.

• They were formed in Munster about 250 million years ago, and were once as high as the Alps.

• However, weathering and erosion have worn them down over millions of years and they are now much smaller.

• Examples include the Magillicuddy’s Reeks, The Galtees, The Comeraghs, and The Knockmealdowns.

Armorican Fold Mountains

Education

Chapter 1 restless earth