1. DO NOW
Pick up notes sheet.

2. REVIEW #9

3. REVIEW #9

4. REVIEW MAFIC minerals are: More dense Associated with Oceanic crust
FELSIC minerals are:
Less dense
Associated with Continental crust
Where would you most likely find MAFIC minerals?
Where would you most likely find FELSIC minerals?

5. Plate Tectonics and Earth’s Changing Surface

6. CONTINENTAL DRIFT Continents move: caused by sea-floor spreading.
widening sea floor.
acts as a conveyor belt.
drifted to their present locations

7. CONTINENTAL DRIFT Supercontinent cycle: Single land masses in past.
Pangaea – “all Earth”
Pangaea split east to west forming Laurasia and Gondwanaland.
Suggests supercontinents will form in future.

8. TECTONIC PLATES – BROKEN CRUST
Broken pieces of Lithosphere.
Move on top of Asthenosphere.
Pulled by convection in mantle.
Fit together like puzzle pieces.
Various sizes and shapes.

9. TYPES OF CRUST Lithosphere crust: Ocean Crust - Mafic
More Dense
Continental Crust - Felsic
Less Dense
Movement:
Together
Apart
Slide past

10. CONVERGENT PLATE BOUNDARIES
Plates move together.
Ocean – Continental
Three types.
Ocean – Ocean
Continental – Continental

11. CONVERGENT PLATE BOUNDARIES
Ocean – Ocean
Ocean plates come together
deep ocean trench, volcanic arc.

12. CONVERGENT PLATE BOUNDARIES
Ocean – Continental
dense ocean crust slips under less dense continental crust.
volcanoes, mountains form.

13. CONVERGENT PLATE BOUNDARIES
Continental – Continental
Continental plates come together.
Folded mountains rise.

14. CONVERGENCE: SUBDUCTION
Latin, means “carried under”.
Convergent zones.
One plate slips under mantle.
Oceanic plates slip into continental ones.
Where ocean plates meet, deep ocean trenches form.
Partial melting creates volcanoes near trenches.

15. DIVERGENT PLATE BOUNDARIES
Plates move apart.
Magma rises to form new land.
Builds Oceanic crust.

16. DIVERGENT PLATE BOUNDARIES
Landforms: Ocean Ridges and Rift Valleys

17. DIVERGENT PLATE BOUNDARIES

18. DIVERGENCE: SEA FLOOR SPREADING
Plates move outward.
Age of ocean crust older farther from center
Magma meets water - cools and solidifies.
Ridge forms around crack or rift at center.
Sediment builds up past ridge - deeper farther from center.

19. PLATE BOUNDARIES: TRANSFORM
Plates sliding horizontally past one another.
Not smooth – rocks lock and scrape.
No magma.
Fracture zones created at mid ocean ridges.

20. PLATE BOUNDARIES: TRANSFORM
Example: San Andreas Fault.

21. FAULTS AND FORCES
Breaks in a body of rock along which crust plates move alongside each other in opposite directions.
Reverse fault
plates PUSH TOGETHER.
Destructive Force.
Convergent boundaries.

22. FAULTS AND FORCES Normal fault plates PULL APART Divergent boundaries
Constructive Force
Strike-slip fault
plates SLIDE PAST each other
Neutral Force
Transform boundaries

23. STRESSES Forces that deform crust. Types of stresses include:
Compression
press or squeeze together.
plates collide.
Convergent boundary.
TAFFY PULL!

24. STRESSES Tension stretch a rock, or pull a plate apart.
Divergent boundary
Shear
lateral motion, causes plates to slide past each other.
Transform boundary
TAFFY PULL!

25. PLATES, FAULTS, STRESSES AND LANDFORMS
Boundaries
Force
Stresses
Faults
Landforms
Convergent
Destructive
Compression
Reverse
Ocean Trenches and Mountains
Transform
Neutral
Shear
Slip-strike
Offset Geology
Divergent
Constructive
Tension
Normal
Rift Valleys and Mid-Ocean Ridges

26. MATCHING THE DIAGRAMS…
Convergent?
Reverse Fault?
Shear?
Transform?
Slip-Strike Fault?
Tension?
Divergent?
Normal Fault?
Compression? B B C C C A A A B

27. Mapping Earth’s Drifting Plates
TODAY’S ACTIVITY
Mapping Earth’s Drifting Plates

28. TO DO
Work on Mapping Earth’s Drifting plates now.