Plates Flashcards
What is a natural hazard? (Plate tectonics)
An event that is potentially dangerous to people - involving humans placing themselves at risk
What is a natural disaster? (Plate tectonics)
Where an event is much larger than expected and damage is great to life and property
What are the characteristics of the crust? (Plate tectonics)
Very thin - around 6-70km
What are the characteristics of the mantle? (Plate tectonics)
Temperatures around 1,300-5,000 degrees
Very high viscosity
What is the outer core made of? (Plate tectonics)
Mainly iron
What is the inner core made up of and what is its temperature? (plate tectonics)
Made of nickel and iron
Around 5,500 degrees
What are the characteristics of the continental crust? (Plate tectonics)
- made of igneous and metamorphic rock
- mainly granite
- crust is less dense but thicker (65km)
What are the characteristics of oceanic crust? (Plate tectonics)
- basalt rock
- crust is not that thick but highly dense
- around 200 million years old
What is the lithosphere made up of? (Plate tectonics)
The upper mantle and the crust
What is the asthenosphere made up of? (Plate tectonics)
Slow moving soft rock
What is the driving force behind the moment of plates? (Plate tectonics)
The heat, leading to convection currents
How do convection currents occur? (Plate tectonics)
Hot molten rises, as it nears the crust it begins to cool, heat moves it back towards the core - the cycle occurs again
What is a natural event? (Plate tectonics)
An event that occurs, that does not present a danger to people or property
