1. The Layers of the Earth!

2. Earth Layers The Earth is divided into four main layers. *Crust
*Mantle
*Outer Core
*Inner Core

3. The Crust
* The Earth’s crust is like the skin of an apple. It is very thin compared to the other three layers.
*The crust, and a part of the mantle just beneath it, makes up Earth’s Lithosphere.

4. The Crust *The crust is the outer most layer of the Earth.
*The temperature ranges from 0oF on the surface to 1600oF below.
*The crust is about 3-5 miles thick under the oceans, and 25 miles thick under the continents.

5. The Crust
*The crust is relatively cold compared to the other Earth layers, so the crust can crack, and cause earthquakes.

6. The Crust
*The crust of the Earth is broken into many pieces, called plates, which float on the mantle located below the crust.
*The crust is composed of common rock silicate compounds.

7. The Mantle The mantle is the layer below the crust.
The mantle is the largest layer of the Earth.
The mantle is divided into two regions: the upper and lower sections.

8. The Mantle *The crust and the upper mantle make up the lithosphere
*The asthenosphere is part of the upper mantle, just below the lithosphere

9. The Mantle
*The temperature is 1600oF at the top and 4000oF near the bottom.
*The mantle is approximately 1800 miles thick.

10. The Mantle
*The mantle is the largest layer of Earth, and is composed of very hot, dense rock.

11. The Mantle
*The composition of the mantle is iron, magnesium, aluminum, silicon, oxygen, and silicate compounds

12. Outer Core * The core of the Earth is like a ball of very hot metals.
* The outer core is liquid.
* The outer core is made up of iron and is very dense.

13. Outer Core
* The temperature is 4000oF to 9000oF, and it is miles thick.
* The outer core is liquid because the material is so hot.

14. Outer Core *The outer core is composed of liquid iron and nickel.
*As the Earth rotates the liquid core spins creating the Earth’s magnetic field.

15. Inner Core
The inner core of the Earth has temperatures and pressures so great that the metals are squeezed together and are not able to move.
* The inner core is a solid.

16. Inner Core *The inner core is the center layer.
*The temperature is around 9000oF.
*The inner core is approximately 800 miles thick.

17. Inner Core
*Pressure from the layers above causes the inner core to be solid.
*The inner core is made of solid iron due to extreme pressure.
*The inner core does not move, but it vibrates in place.

18. Review 1) What are the four layers of the Earth?
2) The Earth’s crust is very ______?
3) The mantle is the largest layer of the Earth? True or False
4)What is the mantle composed of?
5) Is the Outer Core a liquid or a solid?

19. Answers! 1) Crust, Mantle, Outer Core, Inner Core 2) Thin 3) True
4) Iron, magnesium, aluminum, silicon, oxygen, and silicate compounds
5)Liquid