1.1

Question 1

What is the Lithosphere

Answer 1

The lithosphere is the crust and the top layer of the mantle (solid)

Question 2

What is plate tectonic theory

Answer 2

Theory created by Alfred Wegener in 1912 he suggested that tectonic plates move

Question 3

Why do plates move

Answer 3

1) mantle convection currents
2) slab pull
3) subduction zone movement
4) sea floor spreading

Question 4

List the characteristics of the crust

Answer 4

• Up to 400 degrees
• Its solid
• It’s the layer we live on

Question 5

List the characteristics of mantle

Answer 5

• Up to 870 degrees
• Less dense
• Upper part is solid. Lower part is semi-molten

Question 6

List the characteristics of the outer core

Answer 6

• 4400 to 6100 degrees
• Dense
• Liquid iron and nickel

Question 7

List characteristics of the inner core

Answer 7

• 7000 degrees
• Very dense
• Solid (radiates heat)

Question 8

What are the processes at Divergent Processes

Answer 8

Sea floor spreading - rising magma

Large number of shallow focus earthquake

Plates moving apart from one another

Question 9

What are the land forms found at divergent plate boundaries

Answer 9

Shield volcanoes

Rift valleys

Question 10

Characteristics of Convergent plate boundaries

Answer 10

Plates move towards each other

One slides below the other (oceanic) - high magnitude earthquakes

This is called a subduction zone

Question 11

What is a volcanic hotspot

Answer 11

Volcano that exists in the middle of a plate

Question 12

What is a mantle plume

Answer 12

Long-lived areas of high levels of heat flow within the mantle

Question 13

Give three examples of volcanic hotspot islands

Answer 13

• Hawaiian islands
• Galapagos islands
• Canary islands

Question 14

How old is the Hawaii Emperor Sea Mount Chain

Answer 14

5.6 million years ago, to now

Question 15

What is the major type of volcano found in Hawaii

Answer 15

Shield volcano - non eruptive

• gentle slope
• low viscosity - lava flows easily & quickly
• frequent eruptions

Question 16

Explain the reasons for the shape of Hawaii’s volcanoes

Answer 16

Because the volcanoes are not explosive eruptions, the lava easily and gently flows out and hardens creating gentle slopes

Question 17

Why does the hot spot stay in the same place

Answer 17

Magma finds weaknesses in the lithosphere and hardens on sea floor

Question 18

Suggest why there is a sharpe bend in the Hawaiian Island chain

Answer 18

Plate movement changes

Question 19

Intra-plate activity

Answer 19

Occurring within the middle of a plate

Question 20

What does Viscosity mean

Answer 20

How sticky

Question 21

What were the three different suggestions of Alfred Wegener - Pangea

Answer 21

He suggested:
•Biological
•Geological
•climatological

Question 22

Biology evidence of Pangea

Answer 22

• Mesosaurus - small reptile. Fossils and remains found in South America & Africa
• A plant which existed when coal was being formed has been located in India and Antarctica

Question 23

Geology evidence of Pangea

Answer 23

•Rocks f similar age, type, structure and formation found in South Africa and Brazil

Question 24

Climatology evidence for Pangea

Answer 24

• Coal found under Antarctic ice cap

* Evidence of glaciation in Brazil and India

Question 25

What is an Earthquake

Answer 25

Sudden shaking of the ground

Question 26

Where do Earthquakes happen

Answer 26

Along plate boundaries

Question 27

Why do Earthquakes happen

Answer 27

Release of friction/tension of the plates | Caused by sudden movements near the Earth’s surface along a fault

Question 28

What is a fault

Answer 28

A fracture in the rocks that make up the Earth’s crust

Question 29

What is the Epicenter

Answer 29

The point at the surface of the Earth directly above the focus

Question 30

What is the Focus

Answer 30

The point within the Earth where an earthquake rupture starts

Question 31

What are seismic waves

Answer 31

Waves that transmit the energy released by an earthquake

Question 32

List the characteristics of P-Waves

Answer 32

‘P’ =pressure * Travel fast * First waves to arrive * No one knows they’ve passed * Send vibrations, push & pull weakening the rock

Question 33

List the characteristics of S-Waves

Answer 33

‘S’ =Secondary * Travel slow * Pulling rock side to side * People can feel this * Cause damage

Question 34

Like the characteristics of a Surface Wave (L-Wave)

Answer 34

* Large * Move left and right , up and down * Buildings fall

Question 35

What factors can increase the severity of an earthquake

Answer 35

* Hospitals being built furthest away on cheap land * Old buildings, weak - quality comes down to wealth (e.g) Nepal * Buildings closest to river - geology type, softer rock, shakes for longer

Question 36

What are the characteristics of a Shield Volcano

Answer 36

* Non eruptive * Gentle slopes * Low viscosity - lava flows easily and quickly * Frequent eruptions

Question 37

What are Primary effects of an Earthquake

Answer 37

* Ground shaking (which causes infrastructural damage) | * Crustal fracturing

Question 38

What are Secondary effects of an Earthquake

Answer 38

* Liquefaction * Landslides/Avalanches * Tsunami * Aftershocks

Question 39

What is Liquefaction

Answer 39

When land shakes so much the solid particles start to act like a liquid

Question 40

What are the 7 main factors which increase the severity of volcanic hazards

Answer 40

1) Viscosity of the magma - high viscosity = high explosivity 2) Plate margins - convergent margins are the most dangerous 3) Explosiveness 4) The material ejected 5) Distance to populated area 6) Frequency 7) Prediction

Question 41

How is a volcanic eruption measured? | How is it measured?

Answer 41

•Volcano Explosivity Index It is calculated using the ash cloud height and the volume of products ejected into the air

Question 42

Characteristics of Composite volcano

Answer 42

* Steep sides * Formed from very thick, viscous lava that doesn’t flow easily * Lava builds up around the vent * Explosive eruptions relating to viscosity of magma (gases can’t escape)

Question 43

Characteristics of Shield volcano

Answer 43

* Gentle slopes, shield shape * Low viscosity- lava flows easily and quickly * Gentle, non-explosive eruptions * Frequent eruptions (Hawaii)

Question 44

Primary effects of a Volcano

Answer 44

* Pyroclastic Flow * Lava Flows * Tephra and Ash Cloud * Gas eruptions

Question 45

Secondary effects of a volcano

Answer 45

* Lahars | * Jokulhaups

Question 46

What is a Pyroclastic Flows (Primary)

Answer 46

A dense, destructive mass of very hot ash, lava fragments and gassed ejected explosively from a volcano and typically flowing at a fast speed

Question 47

What is a Lava Flow (Primary)

Answer 47

A mass of flowing or solidified lava

Question 48

What is Tephra and Ash Fall (Primary)

Answer 48

All explosive volcanic eruptions generate tephra and produce ash Fragments of rock is explosively ejected

Question 49

What are Gas eruptions (Primary)

Answer 49

Gases that are released during volcanic eruptions

Question 50

What are Lahars (Secondary)

Answer 50

Volcanic mudflow on the slopes of a volcano

Question 51

What are Jokulhlaups (Secondary)

Answer 51

Glacier - typical of glacial outburst flood

Question 52

Why do mudflows occur

Answer 52

When volcanic material mixes with rain and flows

Question 53

Why do eruptions occur

Answer 53

When pressure forces magma from chamber to main vent crater blown off

Question 54

What is formed when lava cools

Answer 54

New rock / land

Question 55

Characteristics of a Tsunami

Answer 55

* Often low in height out at sea (below 300mm) * Grow in height as they hit shallow water * A series of waves * First wave not necessarily the largest or most destructive * Long wavelength can mean up to an hour between waves