1.7 Changes In The Earth And Its Atmosphere

Question 1

What are the only sources of minerals and other resources that humans need?

Answer 1

The earth’s crust, atmosphere, and oceans.

Question 2

Tectonic plates?

Answer 2

The earths crust and upper part of the mantle are cracked into a number of large pieces.

Question 3

Crust

Answer 3

Rocky outer layer beneath your feet.
Thin and made up of giant tectonic plates. These drift slowly on top of the mantle as a result of convection currents.
70km thick
0- 870 degrees celsius

Question 4

Mantle?

Answer 4

Semi solid layer below crust.
Has a very high temp and is able to flow very slowly.
Cooler section near to crust=less mobile than hotter section next to core.
Mantle=mostly solid, but is able to move very slowly.
Up to 2900km thick
1300-4000 degrees celsius

Question 5

Core?

Answer 5

Layer at the centre of the earth, divided into two sections =
The liquid, outer core and the solid, inner core.

Question 6

Outer core?

Answer 6

A liquid layer made up of molten iron and small amounts of nickel, sulfur and oxygen.
As the earth rotates the outer core spins, and this generates the earth’s magnetic field.
Up to 2200 km thick.
4000-5000 degrees celsius

Question 7

Inner core ?

Answer 7

Pressure within the inner core is so great that, even at such high temps, it does not melt.
So inner core is solid.
It mainly consists of iron, nickel and small amounts of lighter elements.
1200km thick
5000-6000 degrees celsius