What causes earthquakes, what are their effects, and how can people prepare for them?
The causes of earthquakes, how they are measured, their effects, and the strategies used to prepare for and respond to them (AO1, AO2).
A focused CCEA GCSE Geography guide to earthquakes. Covers how earthquakes are caused at plate margins, the focus and epicentre, how they are measured, their social, economic and environmental effects, and the prediction, protection and planning used to manage them.
Reviewed by: AI editorial process; not yet individually human-reviewed
Have a quick question? Jump to the Q&A page
Jump to a section
What this dot point is asking
CCEA wants you to explain what causes earthquakes, the key terms focus and epicentre, how earthquakes are measured, the effects they have, and how those effects can be managed. The structure mirrors the extreme-weather dot point: organise effects into social, economic and environmental, and responses into prediction, protection and planning. The extended evaluation question, often comparing richer and poorer countries, carries the highest marks.
How earthquakes are caused
Measuring earthquakes
CCEA expects you to know how earthquakes are measured.
- Richter scale / moment magnitude scale. Measures the magnitude (energy released) using a seismometer. It is logarithmic, so each step up is roughly ten times more ground shaking and about thirty times more energy.
- Mercalli scale. Measures the intensity (the effects and damage observed) on a scale from I to XII, based on what people felt and what was damaged.
The effects of earthquakes
Organise the effects under three headings; the structure earns marks.
- Social impacts (on people): deaths and injuries from collapsing buildings, people made homeless, broken water and power supplies, and the spread of disease afterwards.
- Economic impacts (on money and jobs): destroyed homes, businesses and roads, lost income and jobs, and huge rebuilding costs.
- Environmental impacts (on nature): landslides, fires from broken gas pipes, and, if the epicentre is under the sea, a tsunami that floods the coast.
Managing earthquakes: the three Ps
The damage is reduced by preparation, not by stopping the quake.
- Protection. Earthquake-resistant buildings with deep foundations, steel cross-bracing, rubber shock absorbers and automatic gas shut-off valves stop collapse and fire. This is effective but expensive.
- Planning. Regular earthquake drills, trained emergency services, stockpiled food, water and medical supplies, and clear evacuation routes reduce deaths and speed recovery.
- Prediction. Earthquakes cannot yet be predicted reliably, but monitoring of small tremors and rapid warning systems can give seconds of notice and identify high-risk zones for safer land-use planning.
Worked example: comparing effects by wealth
Common mistakes
Examples in context
Example 1. Why the same magnitude kills very different numbers. A magnitude 7 earthquake in a wealthy country with strict building codes may cause a few deaths because buildings flex and stay standing, while the same magnitude in a poorer country with weak concrete buildings can kill tens of thousands. This shows that the level of development, not just the magnitude, decides the human cost, which is the key idea in the evaluation question.
Example 2. When the quake is under the sea. If an earthquake's epicentre lies beneath the ocean, the sudden movement of the seabed can displace a huge volume of water and send a tsunami racing across the ocean. The 2004 Indian Ocean tsunami killed around 230,000 people because there was no warning system in place. This links the cause directly to a devastating environmental and social effect, and to the value of warning systems.
Try this
Q1. What is the difference between the focus and the epicentre of an earthquake? [2 marks]
- Cue. The focus is underground where the rupture starts; the epicentre is on the surface directly above it.
Q2. Name the scale used to measure the magnitude (energy) of an earthquake. [1 mark]
- Cue. The Richter scale or the moment magnitude scale.
Q3. Give one example of protection and one of planning that reduce earthquake damage. [2 marks]
- Cue. Protection: earthquake-resistant buildings. Planning: earthquake drills or trained emergency services.
Exam-style practice questions
Practice questions written in the style of CCEA exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
CCEA Unit 1 (style)4 marksExplain how earthquakes are caused at plate margins.Show worked answer →
Four marks for explaining the build-up and release of stress.
As tectonic plates move past or against each other, friction makes them stick rather than slide smoothly.
Pressure (stress) builds up over time at the locked margin while the plates keep trying to move.
Eventually the stress overcomes the friction and the plates suddenly jerk free, releasing stored energy as seismic waves that shake the ground.
The point underground where this happens is the focus, and the point directly above on the surface, where shaking is strongest, is the epicentre.
Markers reward the sequence of friction, stress building, sudden release of energy, and seismic waves shaking the surface.
CCEA Unit 1 (style)9 marksTo what extent can the effects of earthquakes be reduced? Use examples in your answer.Show worked answer →
Nine marks, level marked, for a balanced evaluation reaching a judgement.
Protection: earthquake-resistant buildings with deep foundations, cross-bracing, rubber shock absorbers and automatic gas shut-offs reduce collapse and fire, saving lives. This is very effective but expensive, so it is mainly used in richer countries.
Planning: emergency drills, trained rescue services, stockpiled supplies and clear evacuation plans reduce deaths and speed up recovery.
Prediction: earthquakes cannot yet be predicted reliably, but monitoring and rapid warning systems can give seconds of notice and identify high-risk zones for safer land use.
A strong answer weighs these against wealth: richer countries can afford protection and so usually suffer fewer deaths from the same magnitude, while poorer countries rely more on planning and aid. A supported judgement might be that effects can be greatly reduced, mainly through protection and planning, but that prediction remains the weak link and wealth shapes how far it is possible.
Markers reward balance, specific strategies, comparison by wealth, and a clear judgement.
Related dot points
- The structure of the Earth, the theory of plate tectonics, and the features and processes at the different plate margins (AO1, AO2).
A focused CCEA GCSE Geography guide to plate tectonics. Covers the layered structure of the Earth, the difference between continental and oceanic crust, what drives the plates, and the features and hazards found at constructive, destructive, conservative and collision margins.
- The causes and types of volcano, their effects, why people live near them, and how the hazard is managed (AO1, AO2).
A focused CCEA GCSE Geography guide to volcanoes. Covers how volcanoes form at plate margins, the difference between shield and composite volcanoes, their social, economic and environmental effects, the reasons people live near them, and how the hazard is monitored and managed.
- A comparison of the effects of and responses to earthquakes in a more developed and a less developed country (AO1, AO2).
A focused CCEA GCSE Geography case-study guide comparing earthquakes in a richer and a poorer country. Explains why the level of development, not just the magnitude, shapes the effects and responses, using contrasting examples and the framework examiners reward.
- The causes, impacts and responses to an extreme weather event such as a tropical storm or a severe depression (AO1, AO2).
A focused CCEA GCSE Geography guide to extreme weather. Covers what makes weather extreme, how a tropical storm forms, the social, economic and environmental impacts of a major event, and how warning and management reduce the damage.
- The physical, historical, economic and political factors that cause uneven development between countries (AO1, AO2).
A focused CCEA GCSE Geography guide to the causes of uneven development. Covers the physical, historical, economic and political reasons some countries are far less developed than others, and how these factors can trap a country in poverty.
Sources & how we know this
- CCEA GCSE Geography specification — CCEA (2017)
- CCEA GCSE Geography (2017) Unit 1 past papers and mark schemes — CCEA (2024)