Earthquakes
- Created by: Deepali Patel
- Created on: 06-03-13 18:42
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- Earthquakes
- Natural hazard - A naturally occurring event that has the potential to affect people's lives or property
- The centre of the earth is the core. Inner - ball of solid iron and nickel. Outer - liquid. Around it is the mantle, which is semi-molten rock.
- Plates
- The plates move because the rock in the mantle underneath is moving.
- Plate boundaries or margins are the places where plates meet.
- The outer layer is the crust. Very thin - 20km. It's divided into lots of slabs called tectonic plates. Their made of continental and oceanic crust.
- Oceanic - thinner and more dense
- Continental - Thinker and less dense.
- Margins
- Destructive - Two plates move towards eachother. The oceanic plate (denser) is forced down and destroyed. Often creates volcanoes.
- Pressure builds when one plate gets stuck as it's moving down past the other into the mantle.
- They eventually jerk past each other, sending out shock waves. These vibrations are the earthquake.
- Pressure builds along cracks within the plates as they move away from each other.
- Pressure builds up when plates that are grinding past each other get stuck.
- They eventually jerk past each other, sending out shock waves. These vibrations are the earthquake.
- Pressure builds when one plate gets stuck as it's moving down past the other into the mantle.
- Constructive - Two plates are moving away from each other. Magma rises to fill the gap and new land is formed.
- Pressure builds along cracks within the plates as they move away from each other.
- Conservative - Two plates are sliding past each other, or are moving in the same direction at different speeds.
- Pressure builds up when plates that are grinding past each other get stuck.
- Destructive - Two plates move towards eachother. The oceanic plate (denser) is forced down and destroyed. Often creates volcanoes.
- Focus - The point in the Earth where the earthquake starts.
- Epicentre - The point on the Earth's surface, directly above the focus.
- Natural hazard - A naturally occurring event that has the potential to affect people's lives or property
- The outer layer is the crust. Very thin - 20km. It's divided into lots of slabs called tectonic plates. Their made of continental and oceanic crust.
- Oceanic - thinner and more dense
- Continental - Thinker and less dense.
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