Tectonic hazards Flashcards
What is a Tectonic hazard?
Threats caused by the movement of tectonic plates that have the potential to cause damage to life, property, the environment, human activity and/or the economy.
What is a Tectonic plate?
Large slabs in the Earth’s crust. Can either be Continental crust or Oceanic crust.
Why do Tectonic plates move?
Due to the movement of the liquid magma which creates convection currents.
Where do Tectonic hazards occur?
On plate margins.
Name the 3 types of plate margins.
Constructive, Destructive and Conservative.
What do Constructive plate margins do?
They diverge away from each other by ridge push slab pull. (Volcanoes can happen from this but it’s normally very small.)
What do Destructive plate margins do?
Converges towards each other, pressure builds up. (Volcanoes and Earthquakes happen from this.)
What so Conservative plate margins do?
Slide parallel past each other, lots of friction. (Earthquakes can happen because of this.)
What is a Primary effect?
What is directly caused by the natural hazard. e.g. people getting injured or killed and buildings collapsing.
What is a Secondary effect?
The effects that are the result of the Primary effects. e.g. homelessness or a tsunami.
What is an Immediate response?
Action taken as soon as the hazard happens. e.g. reduce loss of life.
What is a Long-term response?
Action taken after the immediate response when the effects of hazards have been minimised. aim to restore normality and reduce risk for the future. e.g. build defence mechanisms.
What are the benefits Tectonic hazards bring?
When volcanoes erupt they emit lots of ash and materials into the air which eventually settles on the surrounding slopes. There are lots of nutrients.
Why do people knowingly put themselves at risk by living near hazards?
(Environmental reasons)
Simply don’t want to leave
May believe defenses will protect them
Just don’t believe hazard will occur
What are economic reasons people may want to live near hazardous areas?
They might have jobs in the local area
The local area might have very good facilities
What are social reasons people may want to live near hazardous areas?
Might not know where to go
Might be language barriers to them leaving.
How does Flood risk affect the risk level?
Fertile silt is good for farming so people will live close to river. Increasing risk of hazard in that area.
How does Cost of land/housing affect risk level?
Some people can only afford to live in hazardous areas - up the side of a mountain - risk of landslide.
How does human activity have a huge impact on climate change?
Humans are responsible for the majority of CO2 that is put into the atmosphere leading to more flooding and extreme weather events.
If a densely populated area is affected…
then more people are going to be affected.
Volcanoes and Earthquakes are commonly found on…
Fault lines - where 2 plates meet.
What are the 2 different types of tectonic plates?
Oceanic and continental.
What is the difference between the oceanic and continental crust?
Continental crust is thicker and denser than Oceanic.
