1. Plate
Tectonics

2. Terminology
The term “plate” refers to the subdivision of the earth’s crust and lithosphere.
The term “tectonics” refers to the deformation of the earth’s crust.
“Plate tectonics” refers to the formation and migration of these plates.
Subduction zone is where two plates come together, and one is forced below the other.

3. It is puzzling!
Alfred Wegener developed a theory that states that all present continents were once together and collectively known as a 'supercontinent' called a Pangaea.
The Pangaea theory was treated with much skepticism when it was first raised. But since then, there have been much evidence to support this theory.

4. There are 3 types of boundaries:
Divergent plate boundaries
Convergent plate boundaries
Transform plate boundaries

5. Divergent plate boundaries
Divergent plate boundaries are where two plates move apart or separate
Magma is heated by convection, rises and pushes the plates apart
This creates a new sea floor
Also called seafloor spreading

6. Rifts and Ridges Great Rift Valley in Africa Mid-Atlantic Ridge
Back to boundary types

7. Convergent Boundaries
This is where two plates come together
One plate is forced to sink below the other
Subduction zone
There are three types of convergent boundaries:
Ocean-continent
Ocean-ocean
Continent-continent
Back to types of boundaries

8. Back to convergent boundaries
Oceanic-continental
The subduction zone is where the oceanic plate is forced below the continental plate.
A deep trench is formed off shore
A mountain range is formed on land
An example is the West coast of North America
Back to convergent boundaries

9. Back to convergent boundaries
Oceanic-Oceanic
Where two oceanic plates converge
A deep ocean trench is formed
A island chain of volcanoes is formed
Examples would be Hawaii or Japan
Back to convergent boundaries

10. Continent-Continent Where two continental plates come together
The plates push together to form a chain of high, jagged mountains
Examples would be The Himalayas
back

11. Transformation boundaries
This occurs between two plates that scrape against each other
At this type of boundary, a fault is created
A common result is an earthquake
A very well known example is the San Andreas Fault in California

12. Now, let’s review!

13. 1) At a divergent plate boundary, how do plates move?
a) Grind past each other
b) Collide with each other
c) Rift apart
d) Move under each other

14. 2) Oceanic trenches are formed by:
a) Sea-floor spreading
b) The collision of continents
c) The subduction of oceanic crusts into the earth’s mantle
d) The subduction of continental crust into the earth’s mantle

15. 3) The supercontinent composed of all of the continents proposed by Alfred Wegener is called:
a) Mantle
b) Pacific
c) Pangaea
d) Plate tectonics

16. 4) Where would an earthquake happen?
a) At a divergent plate boundary
b) At a convergent plate boundary
c) At a transform plate boundary

17. 5) What is not a result of plate tectonics?
a) Hurricanes
b) Volcanoes
c) Earthquakes
d) Mountains

18. OOPS,
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AGAIN
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19. OOPS,
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AGAIN
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20. OOPS,
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21. OOPS,
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22. OOPS,
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AGAIN
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23. GREAT
JOB
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24. GREAT
JOB
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25. GREAT
JOB
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26. GREAT
JOB
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27. GREAT
JOB
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