Hazards Flashcards
What is subduction
A geological process that takes place at convergent boundaries of tectonic plates where one plate moves under another and is forced to sink due to differences in density
What are the characteristics of an oceanic plate (4)
- Younger (younger than 200m years old)
- Thinner (5km)
- Denser/heavier
- Can be both created and destroyed
What are the characteristics of a continental plate (4)
- Older (up to 4 billion years old)
- Thicker (30-70km approximately)
- Less dense
- Can’t be created or destroyed
What is the meeting point of 2 tectonic plates called
A plate boundary
What are the seven primary tectonic plates
- African
- Eurasian
- North American
- South American
- Pacific
- Indo-Australian
- Antarctic
note i dont think you will need to know these so dont worry about learning them, this card is only there in case this helps to add a nugget of information e.g. in an 8 marker
What is deggs model
A Venn diagram with hazards as one part and vulnerable population as the other - the meeting point is disaster
What is a hazard
An extreme event that threatens people, their property and settlements
When does a hazard become a disaster
When the hazard causes widespread destruction to property and human lives
What is risk
The probability of an event happening and the scale of its possible damage
What factors affect the risk of a hazard (6)
- How easily the hazard was to predict
- The fréquency of the events
- The level of mitigation
- The severity of the hazards
- The level of infrastructure
- The education level of the people on how to cope with the hazard
What is a geological hazard
Volcanic eruptions, earthquakes
What is a climatic hazard
Tropical storms
How thick is the outer core
2200km
How thick is the crust and what is it made of
0-70km - granite and basalt
How thick is the mantle and what state is it
2900km, solid but flows
