Chapter 1-4

Question 1

What is the crust?

Answer 1

The crust is solid rock which covers the suface of the earth. The continental crust is thicker than the oceanic crust.

Question 2

What are plates?

Answer 2

The crust is divided into sections. These sections are called plates. There are 11 plates.

Question 3

What is the mantle?

Answer 3

The mantle is under the crust. It is composed of molten magma that is very hot. It floats in currents.

Question 4

What is the core?

Answer 4

The core is the centre of the earth and it is very hot- it is between 3000°C and 5000°C. It is mostly made of iron but it is solid in the middle. It is divided into the inner and outer core.

Question 5

What is continentel drift?

Answer 5

It is the movement of plates. These movements are caused by convection currents.

Question 6

What are convection currents?

Answer 6

Currents in the mantle. The magma is heated by the earths core and rises up to join or seperate under the crust.

Question 7

What are the features caused when plates collide?

Answer 7

Earthquakes, volcanos and fold mountains

Question 8

What is caused when plates separate?

Answer 8

Volcanos, mid-ocean ridges, earthquakes

Question 9

What happens with plates slide past eachother?

Answer 9

Earthquakes

Question 10

What is a cause of plates colliding?

Answer 10

Nazca -> south american
African -> eurasian
Indian -> eurasian

Question 11

Examples of plates colliding?

Answer 11

Pacific ring of fire
Alps
Munster mountains

Question 12

Plates separating?

Answer 12

North american -> eurasian

Question 13

Plates sliding past?

Answer 13

Pacific-> north american plate

Question 14

Examples of plates separating?

Answer 14

Iceland

Mid-atlantic ridge

Question 15

Examples of plates sliding past eachother?

Answer 15

San andreas fault, californa

Question 16

How are fold mountains formed?

Answer 16

When two plates colide the pressure from the plates slowly folds the earths crust into fold mountains

Question 17

What is an anticline?

Answer 17

An upfold

Question 18

What is a syncline?

Answer 18

A downfold

Question 19

Examples of fold mountains?

Answer 19

The Alps
The Andes mountains
The Himilayas

Question 20

What causes the Alps?

Answer 20

The eurasian plate colliding with the african plate

Question 21

What caused the Himilayas?

Answer 21

The Indian plate colliding with the eurasian plate

Question 22

What caused the Andes mountains?

Answer 22

Nazca -> south african

Question 23

How many years ago were the munster mountains formed?

Answer 23

250 million

Question 24

Examples of mountains caused by the amorican folding

Answer 24

Comeragh mountains; Co. Waterford
Caha mountains; Co Cork
Macgillycuddy’s Reeks Co. kerry

Question 25

What is an earthquake?

Answer 25

A series of seismic waves that shake the ground and buildings

Question 26

What is the focus?

Answer 26

The place within the crust where the rock breaks and the earthquake begins, sending out shockwaves or seismic waves

Question 27

What was is the epicentre?

Answer 27

The surface directly above the focus where the most severe tremors occur

Question 28

What are seismic waves?

Answer 28

Vibrations that are sent out by the earthquake

Question 29

What do seismographs measure?

Answer 29

Instruments used to measure seismic waves to find out the severity of an earthquake

Question 30

What is the Richter Scale?

Answer 30

A scale that measures the severity of earthquakes e.g 3 would cause barely any damage but over 9 is near total destruction

Question 31

What are the effects of earthquakes?

Answer 31

* the immediate effects of earthquakes are the displacement of earth and the collapse of buildings which result in the deaths of people in the buildings * the breaking of gas mains, causing fires that destroy buildings * the destruction of communication lines * the spread of disease such as cholera and typhoid due to dirty water * the destruction of the local economy as factories are destroyed

Question 32

What was the cause of the 2011 Japan tsunami?

Answer 32

-Japan is on the Pacific ring of fire | –the epicentre was about 70km off the coast, where the Pacific & Eurasian plate were colliding

Question 33

What were the results of the 2011 earthquake in Japan

Answer 33

* it raised the sea bed by about 8 metres, caused up to 40m tsunami waves * in spite of an early warning system with 1000 seismometers, sirens to warn people and high tsunami walls the waves travelled 10km inland * 25000 deaths, most from drowning * damaged roads, railways and causes a dam to collapse * caused serious problems when the cooling systems in 2 nuclear plants failed and people in a 20km radius had to be evacuated * caused hundreds of aftershocks

Question 34

Why do earthquakes occur along the San Andreas Fault?

Answer 34

It's where the Pacific plate and the North American plate are sliding past eachother

Question 35

What was the most serious earthquake along the San Andreas fault?

Answer 35

The 1906 San Francisco earthquake - 7.9 magnitude - surface moved up with 8 - 3500 deaths

Question 36

What were the effects of the 1906 San Francisco earthquake?

Answer 36

- 80% of the city was destroyed - most of damage and loss of life caused by the burst of gas mains; the water pipes were broken so there was not enough water to control the fires - about 3/4 of the population left homeless

Question 37

What are volcanoes?

Answer 37

Openings or cracks in the earth's crust through which magma, ash, cinder and gases pour or erupt

Question 38

The formation of a cone-shaped volcano?

Answer 38

1. Magma seeps up from the magma reservoir in the mantle through cracks in the crust, when pressure builds up near the surface this causes a violent eruption that fires ash, cinder and gas into the sky 2. Lava flows out of the crater at the top of the volcanic mountain and down the sides,the lava cools and hardens 3. Layers of lava and ash are laid down during different eruptions which build up to form a cone-shaped volcano with a crater at the top 4. Sometimes a secondary volcano develops on the main cone

Question 39

What is a crater?

Answer 39

The mouth of the volcano from which lava, ash, cinder and gases escape

Question 40

Vent

Answer 40

The crack in the crust from which the volcano builds up from a series of eruptions

Question 41

What is the magma reservoir?

Answer 41

The magma reservoir is down in the mantle, the magma/lava comes from here

Question 42

Magma

Answer 42

The molten rock while its underground

Question 43

Lava

Answer 43

Molten rock when it comes above the ground

Question 44

What is the mid-Atlantic ridge?

Answer 44

A series of mid-ocean ridges (line of mountains/volcanoes) which are caused by the North America and Eurasian plates spreading

Question 45

What are the volcanic features of Iceland?

Answer 45

- volcanoes: Mt Hekla - geysers: throw up jets of water and steam regularly - geothermal springs

Question 46

Types of volcanoes?

Answer 46

* active: Mt Vesuvius * dormant: Cotopaxi * extinct: Slemish Mountain

Question 47

HOW VOLCANOES IMPACT ON HUMAN ACTIVITIES | Advantages if volcanoes

Answer 47

* fertile soils are created from the breakdown of lava e.g Mt Vesuvius in Italy * geothermal springs provide hot water and central heating e.g Iceland * new land is formed e.g Surtsey off Iceland * tourist visit volcanoes or towns destroyed by volcanoes e.g Pompeii or distinctive landscapes cause by volcanoes e.g Giants causeway

Question 48

HOW VOLCANOES IMPACT ON HUMAN ACTIVITIES Disadvantages of volcanoes

Answer 48

* many people killed and towns and cities are destroyed e.g Pompeii * farming land is destroyed * Lahars can cause great damage * Icelandic ash clouds disrupt air travel