1. Forces Shaping the Earth
Chapter 1 Section 3
Forces Shaping the Earth

2. Inside the Earth
The earth has 3 layers.
Core
Mantle
Crust

3. Core Center of the Earth
Inner Core -Dense area consisting of hot iron mixed with rock and other metals.
Outer Core – so hot that the metal melted into a liquid.

4. Mantle
Layer of rock surrounding the core measuring about _______________ miles thick.
Mantle has two parts:
Inner mantle – solid - rock
Outer mantle – liquid- melted rock
What is melted rock known as _______________________.

5. Crust Uppermost layer of the earth
Thin layer measuring only about ______________ miles thick
Crust includes the ocean floors, as well as the 7 ____________________.
Crust is thinner on the ocean floors, than it is under the continents.

6. Structure of the Earth

7. Forces Beneath the Earth
Plate Tectonics – crust is not an unbroken shell but rather a series of plates, or huge slabs of rock.

8. Forces Shaping the Earth
Tectonic Plates move in all different directions.
Millions of years ago, the plates were connected scientists call this ____________.
A: Pangea

9. Pangea

10. When Plates Meet

11. When Plates Meet
Plates move in all different directions, they can move away, push against, or slide along side each other.
Plates can smash into one another
This forms _______________________
A: Mountains
Himalayans in South Asia formed in this manner

12. Mountains

13. When Plates Meet
Continental Plates and Ocean Plates move against each other
Continental plates are heavier and go over the Ocean plate
Lower plate causes pressure to build up which causes and volcanic eruption with magma
Pressure also builds between the two plates, and then an earthquake can occur.

14. Volcanoes

15. Ring of Fire
Huge area in the Pacific Ocean between Asia and the United States.
Circle forms from the large amount of active volcanoes found there

16. When Plates Meet
Earthquakes are sudden movements of the earth’s crust.
Earthquakes can also occur when plates slide along side each other.
The sliding motion causes pressure to build up, cracks begin to form.
Fault line – cracks in the earths crust.
San Andreas Fault in California is a huge fault line that causes many deadly earthquakes.

17. Earthquakes

18. Tsunami
When an earthquake occurs underwater, it can cause a huge wave to form.
Waves can be very deadly and reach several feet high.

19. Tsunami

20. Forces Shaping Landforms
Weathering – the process of breaking surface rock into boulders, gravel, sand and soil.
Causes of Weathering:
Water
Frost
Chemicals
Plants

21. Erosion
Erosion – the process of wearing away, or moving weathered materials.
Causes of weathering:
Water
Wind
Ice –glaciers huge slabs of ice that change the land as they move over it.
Erosion is earths scrub brush.
Glaciers are earth’s sandpaper.