Crust
the outer layer of the Earth (solid, thin layer)
Mantle
The layer beneath the crust (semi-liquid, thick)
Outer core
Layer beneath the mantle (liquid iron)
Inner core
Centre layer (solid iron)
Tectonic plates
The crust split into several pieces. These large pieces of rock are called tectonic plates. They float on the mantle.
Constructive plate boundaries, definition and example.
2 plates move away from each other due to convection currents. Eg. Mid-Atlantic Ridge (Eurasian plate and North American plate)
Plate boundaries/margins
where tectonic plates meet
Oceanic Crust
Crust found under the oceans (thinner (5-10km), younger, more dense)
Continential Crust
Crust found under land (thicker (25-100km), older, less dense)
Destructive plate margin, definition and example
2 plates move towards each other, oceanic plate is subducted under continential plate. E.g Philippines plate subducted under Eurasian plate.
Conservative plate margins, definition and example
2 plates move past each other, different or same direction but different speed. E.g North American Plate and the Caribbean Plate.
What is the fault line?
The line between 2 plates.
Collision plate margin, definition and example.
2 plates of the same density collide and are forced upwards as mountain ranges. These are known as fold mountains. E.g Himalayas was formed due to the collision of the Eurasian and Indian plates.
Natural hazard
A natural process that poses a potential threat to people and property.
Meteorological hazard
A hazard that occurs in the atmosphere such as floods, droughts, landslides, tides, sea level rise, wind snow, frost, extreme temperature, hail, lightning, and fire.
Tectonic hazard
A natural hazard caused by movement of tectonic plates (including volcanoes and earthquakes).
Earthquake
A sudden or violent movement within the Earth's crust. It is caused by a build up and sudden release of pressure/tension.
Shockwaves
As the tectonic plates suddenly move, they send out shock waves (vibrations) from the point of movement in the Earth's crust.
Focus
The point of movement in the Earth's crust.
Epicentre
The point directly above the focus is called the epicentre. The closer you are to the focus and epicentre, the more violent the arty quake will be.
Magnitude
The amount of energy released during an earthquake.
Seismometer
The instrument that measures the magnitude of an earthquake.
Richter scale
The scale on which earthquake magnitude is measured. The higher the magnitude on a Richter scale, the more powerful the earthquake
A reason why LICs are affected worse by earthquakes is quality of infrastructure. Explain
Infrastructure (buildings, ports, roads) have a lower quality in LICs therefore they are more likely to collapse in the event of an earthquake, trapping people underneath. HICs often have earthquake proof buildings.
Another reason why LICs are affected worse by earthquakes than HICs is that they are unable to meet the cost of immediate response to earthquakes. In other words...
Search and Rescue, Clear rubble, build temporary structures. HICs can ,however, immediately respond to earthquakes, which means there is a lesser loss of life.
LICs also don't have many planning and prediction strategies, so...
They are unable to predict when the earthquakes will occur or prepare people for when it does occur.
Where is L'Aquila and when did the earthquake occur?
Italy, April 2009
What was the magnitude of the L'Aquila earthquake on the Richter scale?
6.3
How many people were found dead and injured in the L'Aquila earthquake?
308 dead, 1500 injured
How many buildings were destroyed in the the L'Aquila earthquake?
10-15k, including a hospital, a bridge also collapsed.
How many people were made homeless in the L'Aquila earthquake?
67,500
What is a secondary effect of the buildings collapsing (the L'Aquila earthquake)?
Fires in the buildings.
What happened after a pipeline burst (the L'Aquila earthquake)?
It caused a landslide.
How much did the repair of the bridge cost (L'Aquila earthquake)?
$11,434 million
What were the immediate responses to the L'Aquila earthquake?
Camps were set up for the homeless, providing medical care and food. British Red Cross raised £171,000 Ambulances, fire engines and the army were sent to rescue survivors Italian post office provided free mobile phones and SIM cards for people who had lost their homes Government suspended mortgage, gas and electric payments
What were the long term responses to the L'Aquila earthquake?
New settlements built for 20,000 residents City centre has been rebuilt Residents did not have to pay taxes in 2010 Students did not have to pay university fees for 3 years
Why do people live in areas of high risk?
Friends and family Employment Confident the government will protect them (planning and prediction) The land is very fertile near volcanoes (good for farming) They do not know it is unsafe (lack of education)
Monitor earthquake prone areas to PREDICT when it will occur.
Previous Earthquake Data
Historical records can be used to show patterns and trends. These can be used to predict future earthquakes.
Monitor earthquake prone areas to PREDICT when it will occur. 2)Measure for Small Tremors
Before a large earthquake often there is an increase in the number of small tremors. Scientists use seismometers to record any ground movement.
Monitor earthquake prone areas to PREDICT when it will occur. 3) Unusual Animal Behaviour
Animals often act strangely before an earthquake. In China, the city of Haicheng was evacuated following strange animal behaviour. Days later a 7.3 magnitude earthquake struck. It is estimated it saved 150,000 lives.
Where is Haiti and when did the earthquake occur?
The Caribbean Islands, January 2010
What was the magnitude of the Haiti earthquake?
7.0
How many people were found dead and injured in the Haiti earthquake?
220,000 dead, 300,000 injured.
How many homes were damaged or destroyed in the L'Aquila earthquake?
300,000
How many hospitals were destroyed in the Haiti earthquake?
8
How many schools were destroyed or damaged in the Haiti earthquake?
5000
What happened as a result of fallen buildings?
Transportation routes (roads, rails,ports, airports) were destroyed
Service lines were also destroyed. What is meant by service lines?
Water, gas, electricity
What were the immediate responses to the Haiti earthquake?
People were evacuated. USA sent ships, helicopters and the army to search and rescue for victims and clear the rubble at the port so that companies could start to export goods again. UN sent police to distribute aid and keep order. The Red Cross set up temporary hospitals. The UK raised £100 million for emergency aid. USA gave $100 million for emergency aid.
What did the amount of dead bodies lead to?
Trauma and diseases from dead bodies.
Homes destroyed or damaged meant that...
1.3 million Haitians had to stay in temporary camps.
The destroyed hospitals caused...
Unemployment.
After the Haiti earthquake, crime rates...
Increased.
Transportation routes were destroyed during the Haiti earthquake. This meant that...
Aid supplies could not reach victims.
Transportation routes were destroyed during the Haiti earthquake. This meant that...
2 million Haitians were left with no electricity ,water or food
How much did the repair of service lines cost (Haiti earthquake )
$11.5 billion.
What were the long term responses to the Haiti earthquake?
Relocation - 1000s left Port-au-Prince permanently Cash for work programs set up to clear rubble to give locals jobs in the long term. World Bank gave $100 million to support long term reconstruction in Haiti. ¾ of the buildings were repaired.