The core, the mantle and the crust
Before starting work on this topic it is vital that you know the structure of the earth, as it underpins a majority of the work related to natural hazards. The diagram below summarises the most important points:
Place the cursor over the various sections of the earth to see what they are called:
Crust
- Thin, outer-layer of the earth.
- It is as thin as the skin of an apple is to its flesh.
Mantle
- Composed mainly of silicate rocks, which contain a lot of magnesium and iron.
- It extends to a depth of 2900km.
- Temperatures can reach 5000 degrees Celsius, which generate convection currents.
Core
- Contains iron and nickel.
- Situated approximately 6371km below the surface.
- Temperature is around 5500 degrees Celsius.