The structure of the Earth

Question 1

What is the layer on the outside of the Earth?

Answer 1

the crust

Question 2

What are the two types of crust?

Answer 2

• oceanic

- continental

Question 3

Describe oceanic crust:

Answer 3

• made up of dense, heavy metals
• it is younger than continental crust
• it can sink
• it can be destroyed

Question 4

Describe continental crust:

Answer 4

• made up of light metals
• it is older than oceanic crust
• it can’t sink - not heavy enough
• it is permanent so can’t be destroyed

Question 5

What is underneath the crust?

Answer 5

Underneath the crust is mantle. Here the temperatures are so high that rock still exists in a semi-molten state - like treacle.

Question 6

What is underneath the mantle?

Answer 6

• the outer core (liquid)

- the inner core (solid)

Question 7

What is the outer core made from?

Answer 7

• molten metals

Question 8

What is the inner core made from?

Answer 8

• heavy metals

Question 9

Which core is thinner?

Answer 9

The inner core (solid) is thinner, but has a higher temperature.

Question 10

How do plates move?

Answer 10

Heat from the centre of the earth sets up convection currents in the mantle. When these currents reach the surface they cause the plates above them to move.

Question 11

What are the 3 directions that plates can move?

Answer 11

• towards each other
• away from each other
• sliding past each other

Question 12

What is a plate boundary?

Answer 12

A plate boundary is where two plates meet, and this is where most of the world’s earthquakes, volcanoes and high mountain ranges are found.

Question 13

What is the thickest layer of the earth?

Answer 13

• mantle

Question 14

Do plates move very quickly?

Answer 14

No, plates move very slowly.