Natural Hazards Flashcards
Describe a destructive plate boundary
- oceanic crust subducts underneath the continental crust as it is denser and thinner
- friction and the plates getting stuck causes bursts of energy to be released as earthquakes
- the oceanic crust reaches the mantle where it melts into magma
- this rises and forms volcanoes
Describe a constructive plate boundary
Two of the same plates move away from each other
This causes magma to rise from the mantle which hardens on the surface to form new crust
It also forms volcanoes
Describe a collision boundary
A collision boundary is two continental plates moving towards each other, this makes the land crumple into each other and try and move over each other. As they move, this causes friction, leading to rapid energy released as it gets stuck over one another. This is in the form of earthquakes
It forms mountains suck as the Himalayas
Describe a conservative boundary
The crusts slide either in opposite directions or in the same direction at different speeds
Volcanoes are not formed here as magma is not rising from the surface and nothing is being destroyed.
The crusts get stuck over one another, causing friction to be released in bursts which are in the form of earthquakes
Why would you live in a risk zone?
- volcanoes aren’t likely to erupt same with earthquakes
- some may not be aware of risks
- volcanoes make fertile soil for crops
- buildings are strong enough to withstand earthquakes
How can you reduce the risks of hazards?
- buildings could have automatic shutters to avoid glass breaking with earthquakes
- walls are reinforced with steel so they are stronger
- the foundation is reinforced
- monitor volcanoes by measuring gas as it rises from the ground
- geophysics measurements of changing gravity
- it’s harder to monitor earthquakes
- plan out risk areas and make sure that land isn’t used
- you can predict when earthquakes are going to happen through past knowledge
