Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

GCSE AQA Geography > Tectonic Hazards > Flashcards

Tectonic Hazards Flashcards

1
Q

What is a natural hazard?

A

A natural event that has social impacts / A natural event that overlaps with human activities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a hazard risk?

A

The chance of being affected by natural events

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are four different types of hazards?

A

Volcanic eruption: Hot material such as lava is thrown out from a volcano

Earthquakes: When the ground shakes

Tsunami/Hurricane/Cyclone: A huge wave caused by an earthquake/volcanic eruption under the ocean

Landslides: Collapse of the earth from mountains or cliffs

Floods: When the water overflows from a river

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the three main groups of natural hazards?

A

Geological hazards: hazards caused by processes e.g volcanoes, earthquakes, landslides

Hydrological hazards: hazards caused by the movement of water on land e.g flooding

Atmospheric hazards: hazards caused by the weather e.g. tropical storms, droughts tornadoes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What factors affect risk?

A

Urbanisation - Cities are densely populated areas so when an earthquake occurs more people are at risk

Climate change - Global warming leads to oceans becoming warmer. This will increase the number and intensity of tropical. (Ice caps lead to rising sea levels, increasing the risk of flooding)

Farming - When a river floods it leaves behind fertile silt which is good quality soil for growing crops. Therefore farmers will choose to put themselves at risk and live on floodplains so they can grow crops for food and income.

Poverty - People don’t have enough money to move so have no choice but to live in hazardous areas with poor construction e.g. landslides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is an earthquake?

A

Earthquakes are vibrations in the Earth’s crust that create shaking at the surface. They are highly unpredictable and often occur suddenly without warning, mainly on the plate margins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the structure of the earth

A

Crust - the outermost layer of the Earth, broken into tectonic plates.
Mantle - semi-molten part of the Earth.
Outer core - liquid iron and nickel
Inner core - solid iron and nickel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the earth’s crust broken into?

A

Tectonic plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the oceanic crust?

A

The part of the Earth’s crust below the oceans.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the continental crust?

A

The part of the Earth’s crust that makes the continents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the differences between the continental crust and the oceanic crust?

A

Oceanic crust is thinner (5-10km thick) and denser than the continental crust.

Oceanic crust is recycled at destructive margins as it subducts under the continental crust.

Continental crust is thicker (20-200km thick) and is less dense than the oceanic crust.

Continental crust cannot be destroyed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is it called when two plates meet?

A

Plate boundary/plate margin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are convection currents?

A

Circulating movements of magma in the mantle caused by the heat of the core

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why do tectonic plates move?

A

Powerful convection currents in the mantle drag them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the global distribution of earthquakes

A

Earthquakes are distributed in long, narrow, linear belts at plate boundaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where are earthquakes concentrated?

A

Around plate boundaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is an oceanic trench?

A

Long, narrow depressions on the seafloor formed at some of the deepest points of the ocean

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How many types of plate boundaries are there?

A

There are three types of plate boundaries: constructive, destructive and conservative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What occurs at constructive plate boundaries?

A
  1. Two plates move away from each other
  2. Magma from the mantle rises up to the surface
  3. Magma reaches the surface and cools to create new ocean floor
  4. The seafloor is ‘spreading’ (as plates are always moving apart)
  5. This creates volcanic islands and mid-ocean ridges
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What occurs at destructive plate boundaries?

A
  1. When the oceanic plate is subducted underneath the continental plate, an oceanic trench is created
  2. The two plates lock ‘like a machine without oil’ and pressure builds up
  3. When this pressure is suddenly released, it sends shockwaves to the surface, causing an earthquake
  4. The oceanic plate continues to subduct and begins to melt because of heat and friction from the mantle
  5. This creates new magma which is lighter than the existing magma. This rises to the surface causing a volcanic eruption.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What occurs at conservative plate boundaries?

A
  1. When the plates slide past each other the two plates lock ‘like a machine without oil’
  2. Pressure builds up at the focus
  3. When this pressure is suddenly released, one of the plates jerk forward
  4. This sends shockwaves to the surface causing another earthquake
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are earthquakes measured on?

A

The Richter Scale

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the strongest and weakest number?

A

9 is the strongest, 1 is the weakest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is magnitude?

A

The size of an earthquake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are seismic waves?

A

Vibrations/waves of energy given out in an earthquake

26
Q

What is the focus?

A

Where the plates lock below the ground / The origin of an earthquake

27
Q

What is the epicentre?

A

Directly above the focus on the surface

28
Q

Where is the earthquake strongest?

A

Near the epicentre

29
Q

What are primary effects?

A

The immediate effects caused by the ground shaking e.g. houses collapsing

30
Q

What are secondary effects?

A

Caused directly by the primary effects e.g. people becoming homeless

31
Q

Can we predict volcanic eruptions and earthquakes?

A

Volcanoes - Yes
Earthquakes - No

32
Q

At which plate margins can earthquakes occur?

A

All plate margins (constructive, destructive and conservative)

33
Q

At which plate margins can volcanoes occur?

A

Constructive and destructive plate margins

34
Q

Is Chile a HIC or LIC?

A

HIC

35
Q

When did the Chile earthquake occur?

A

27th February 2010

36
Q

What was the strength of the Chile earthquake on the Richter scale?

A

8.8

37
Q

Explain the primary effects of the Chile earthquake

A
  • 500 people killed, 12,000 injured
  • 220,000 homes destroyed - thousands of people becoming homeless
  • 56 hospitals destroyed - increasing mortality rate as lack of medical attention
  • Santiago airport badly damaged - causing delays, no-one could enter or exit the country
  • Lost power and communiations - blackouts due to power loss also lack of communications making it hard for people to contact each other and receie updates on the situation
  • Lost water supplies - diseases such as cholera can spread leading to death if not treated
38
Q

Explain the secondary effects of the Chile earthquake

A
  • 1500km roads damaged by landslides - caused disruption/delays for people wanting to use cars and caused delays in help getting to areas of need. Makes it harder for people to evacuate quickly
  • Coastal town damaged by tsunamis - coastal communities devastated by flooding, houses destroyed, lives lost, peole injured
  • Fire outbreak at a chemical plant near Santiago - forcing people to evacuate and forcing the chemical plant to shut down. Meaning people were left unemployed and lost income
39
Q

Is Nepal a HIC or LIC

A

LIC

40
Q

When did the Nepal earthquake occur?

A

25th April 2015

41
Q

What was the strength of the Nepal earthquake on the Richter scale?

A

7.9

42
Q

Explain the primary effects of the Nepal earthquake

A
  • 9,000 people killed, 20,000 injured
  • 7,000 schools were destroyed - people left uneducated
  • Hospitals were overwhelmed - Hospitals could not cope with the number of casualties due to lack of resources and doctors
  • 50% of shops destroyed - Affected food supplies and people’s livelihoods (unemployed)
  • International airports became congested with aid - Airports were too busy, chaotic and not efficient enough to distribute aid to people
  • Homes destroyed - left 3 million people homeless
  • Electricity, water supplies, sanitation and communications affected - blackouts, spread of diseases such as cholera, not able to reach loved ones
43
Q

Explain the secondary effects of the Nepal earthquake

A
  • Landslides - blocked roads, slowing down relief to reach areas of need.
  • Avalanches - Killed 19 people on Mt. Everest
44
Q

Why do the impacts of earthquakes differ in countries?

A

The impacts of earthquakes differ in countries due to wealth and development. HICs are wealthier and will cope better with the impacts of earthquakes compared to LICs.

45
Q

Give 4 reasons why HICs cope better with the impact of earthquakes compared to LICs

A
  • Building regulations - ensures good quality material is used and safety regulations are put in place
  • Life-safe buildings - can afford earthquake-resistant buildings, meaning buildings won’t collapse. This means people won’t lose their homes and become homeless
  • Trained firefighters and rescue teams - rescue teams are better equipped to deal with the situation and also have the resources e.g. heat detectors to detect people trapped under debris
  • Hospitals well resourced - trained doctors to deal with emergency situations, enough medicine available to treat the injured
  • Technology - geographical information system (GIS) to detect areas of danger and safety, helps with planning rescue/evacuation
46
Q

What is response?

A

The way in which people react to a situation eg. an earthquake

47
Q

What are immediate responses?

A

Actions which are carried out quickly to save lives

48
Q

What are long-term responses?

A

Actions carried out over a period of time to rebuild

49
Q

What were 4 immediate responses to the Chile earthquake?

A
  • Emergency services acted quickly - rescue workers immediately went to the area of dangers to evacuate people
  • Temporary repairs made to important route 5 highway within 24 hours - allowed aid, rescue workers to commute to areas of danger. Allowed peole to evacuate areas of danger
  • Power and water restored to 90% of homes within 10 days - No blackouts and reduces risk of water borne diseases
  • A national appeal raised $60 million - was used to build 30,000 small emergency shelters for people in need to use
  • International help needed to supply field hospital, satellite phones and floating bridges - ensuring doctros were well resourced with equipment and medicine to save lives. Phones allowed communication.
50
Q

What were 3 long-term responses to the Chile earthquake?

A
  • Housing reconstruction plans - to help 200,000 households affected by the earthquake
  • Rebuidling the economy - this was done through exporting copper and not relying on foreign aid
  • Rebuilding ports and buldings could take up to 4 years - rebuilding of ports are vital for trade (to export and import goods)
51
Q

What were 4 immediate responses to the Nepal earthquake?

A
  • Search and rescue teams - searching for victims trapped under collapsed building or rubble
  • Foreign aid - international help providing water and medical support (from UK, India and China)
  • Helicopter rescue team - evacuating people caught in avalanches on Mt. Everest. Helicopters also delivered supplies to villages cut off by landlsides
  • Social media - used for search and rescue operations and satellite mapped damaged areas
52
Q

What were 4 long-term responses to the Nepal earthquake?

A
  • Roads repaired and landslides cleared - to reduce traffic delays, people can commute as normal. Aid can reach areas of need quickly
  • Lakes need to be emptied due to landslides - to avoid flooding
  • Damaged houses repaired and rehousing project - rehousing people
  • 7000 schools rebuilt or repaired - people can go back to education
  • Stricter controls on building codes - to increase safety so buildings won’t easily collapse
  • International conference - to seek advice from other countries on reconstruction and seek technical and financial suport
53
Q

Why do people live in hazardous areas?

A
  • Natural hazards don’t happen very often - people think it occurs very rarely so don’t see it as a threat
  • Better building design - life safe buildings can withsatnd earthquakes so people feel less at risk
  • Effective monitoring of volcanoes and tsunamis - people receive warnings and evacuate before events happen
  • Volcanoes bring benefits - such as fertile soil for farming, geothermal energy provides electricity e.g. Iceland
  • People unaware - people do not know that they are living near a plate boundary and the risks associated with it
  • Poverty - people cannot afford to move and have no choice but to live in hazardous areas
54
Q

What benefits have volcanoes brought to Iceland?

A
  • Hot water from within the earth’s crust - provides heat and hot water for nearly 90% of all buildings in Iceland
  • Volcanic rocks - used in construction for roads and buildings
  • Tourism - people come to view the volcanic scenery, this creates jobs and generates income for the country
55
Q

What are the strategies used to reduce the effects of earthquakes?

A
  1. Monitoring
  2. Prediction
  3. Protection
  4. Planning
56
Q

What is monitoring?

A

Using scientific equipment to detect warning signs of events e.g volcanic eruption

57
Q

What is prediction?

A

Using historical evidence and monitoring to try and predict when and where a hazard may occur

58
Q

What is protection?

A

Designing buildings that will withstand tectonic hazards

59
Q

What is planning?

A

Identifying and avoiding places at most risk

60
Q

What are three features of life safe buildings?

A
61
Q

Give four items you can include in an emergency kit

A

GCSE AQA Geography (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions