Forces of Change
- For hundreds of millions of years the earth's surface has been in slow but constant movement.
- Some things change the earth such as, wind and water but these changes occur on the earth's surface.
- Here are some other things that cause the earth to change just on the interior of the earth, volcanic eruptions and earthquakes.
- The earth is divided into 4 layers
- These layers are, (from outer most layer to inner most layer) Crust, Mantle, Outer Core, Inner Core.
Earth's Structure (part 2)
- Continental Drift is the theory that all the plates of the earth were all connected but they slowly drifted apart.
- The plates move so slowly that they only move about 4 inches a year.
- When the plates spread apart magma is pushed up from the earths surface.
- When two plates bump together and one plate goes under the other is called a subduction zone.
- Scientist use the term Plate Tectonics to refer to the plates activities
- Scientist have not yet discovered what causes plate tectonics.
Internal Forces Of Change
- Mountains are formed by converging plates.
- A subduction zone is where two plates collide and one plate goes under the other.
- Earthquakes and Faulting happen when two plate slide against each other this is know as Transforming
External Forces of Change
- There are many things that change the earth but wind and water are the main ones.
- Here the specific names of these types of changes, Weathering, Wind Erosion, Glacial Erosion and Water Erosion.
- These are all different ways to change the earths surface.