The Structure Of The Earth Flashcards
1
Q
3 sections of the Earth
A
Core
Mantle
Crust
2
Q
What is the crust divided into?
A
Plates
3
Q
How often do plates move?
A
About 7 cm each year
4
Q
What is the mantle?
A
The semi-liquid section below the crust upon which plates float.
5
Q
What is the core?
A
The very hot sphere in the centre of the Earth mainly composed of an iron-nickel alloy as well as some other elements.
6
Q
Explain how convection currents cause plate movements. [3]
A
- The hot core heats the mantle, causing convection currents.
- As they reach the top of the mantle and spread out, they drag the plates slowly apart.
- When the convection currents cool and sink back down towards the core, they drag the plates above them closer together.
