1. PLATE TECTONICS AND CONTINENTAL DRIFT
AUGUST 30, 2016

2. FALCON FOCUS
SOLVE THE PUZZLE ON THE NEXT SLIDE

4. ESSENTIAL QUESTION
What evidence supports that at one time the continental plates were together as Pangaea?

5. Plate Tectonics…what is it?
Plate tectonics is the theory that explains the formation, movement and subduction of Earth’s plates

6. How do the Plates move?
The plates of the Earth move because of Convection Currents in the asthenosphere rising and causing the movement.

7. What happens when the plates move?
No plate can budge without affecting the other plates surrounding it.
As the plates move, they collide pull apart, or grind past each other producing changes in the Earth’s surface.

8. What kind of Changes?
Volcanoes! Earthquakes! Mountain ranges! Sea-trenches!

9. Where are these plates?
IN THE LITHOSPHERE!

10. PROOF or it didn’t happen…
EVIDENCE #1 The continents used to fit together like puzzle pieces before the plates moved them apart Scientists call this Supercontinenet: PANGAEA How do I say that?? PAN-GEE-UH

11. Continental
drift
Continental drift was Wegener’s theory that all continents had once been joined together in a single landmass and have drifted apart since.
Wegener named this supercontinent Pangaea.
Wegener’s theory was rejected by scientists because he could not explain what force pushes or pulls continents.
Continental drift video clip

12. Wegener
earthobservatory.nasa.gov
Alfred Wegener first proposed the theory of continental drift.

13. As the plates continued to move and separate, OCEANS formed Landmasses collided and split apart until they ended up where they are now

14. PROOF or it didn’t happen…
EVIDENCE #2 Fossils on different continents are similar to fossils on continents that were once connected. When the continents split, different life forms developed. Continents that were once connected also have identical landform shapes and features and identical rock formations

16. PROOF or it didn’t happen…
EVIDENCE #3
Most features on land and in the ocean are the result of geological activity and earthquakes along plate boundaries (where the pieces meet).
The exact patterns depend on HOW the plates are moving… together – apart – or sliding.

17. What else do we know?
The plates are still moving!! Though they move VERY SLOWLY  between 1-10 centimeters per year

18. What else do we know?
There are places within the lithosphere where magma rises and leaks through the crust This is called a HOT SPOT and is where volcanic activity occurs. HOTSPOTS are how the Hawaiian islands were formed!!

19. CONVERGENT PLATE BOUNDARY
AUGUST 31, 2016

20. FALCON FOCUS - REVIEW CHECK
What are two evidences of the continental drift theory?
What is Pangaea?
Where are the tectonic plates located?
What part of the Earth do tectonic plates float on?
How do tectonic plates move?

21. ESSENTIAL QUESTION
What landforms result from a Convergent Boundary?

22. Plate Boundaries Boundaries
Plates float on the upper mantle (Asthenosphere) They move due to Convection Currents
The edges of the different plates meet at lines called
Boundaries
At the border of plate boundaries are….
FAULTS—breaks or cracks in the Earth’s crust

23. Types of Boundaries
There are 3 different types of boundaries that occur because of their different movement
Convergent Boundaries
Divergent Boundaries
Transform Boundaries

24. Convergent Boundaries
2 plate boundaries come together or collide
A collision is when two plates hit each other
CRUST
CRUST

25. What happens when they hit?
The DENSITY of the crustal plates colliding determines if either…
A) One plate goes under the other
B) The plates rise up
Either way…. An Earthquake can always (and often does) occur when two plates interact

26. Collisions
PREDICTION TIME: Basalt (what Oceanic Crust is made out of) is more dense than Continental Crust.
What do you think will happen to the plate that is MORE dense?

27. SUBDUCTION ZONE CRUST INVOLVED: OCEANIC & CONTINENTAL
MOVEMENT: More dense plate (Oceanic) slides under or sinks below the less dense Continental plate.
FORCE/STRESS ON THE ROCK: Compression (push or squeeze rocks)
LAND FORMS:
Trenches, crust going below into the mantle melts and recycles
Island arcs and volcanic arcs (small mountain ranges)

28. SUBDUCTION ZONE

29. SUBDUCTION ZONE

30. TRENCHES

31. ISLAND ARC

32. VOLCANIC ARC

33. MOUNTAINS & VOLCANOES CRUST INVOLVED: CONTINENTAL & CONTINENTAL
MOVEMENT: Both plates buckle and push up
FORCE/STRESS ON THE ROCK: Compression (push or squeeze rocks)
LAND FORMS:
Mountain ranges
Volcanoes
AND EARTHQUAKES!
INCRUST INVOLVED: CONTINENTAL and push up
AND EARTHQUAKES!OLVED: CONTINENTAL & CONTINENTAL \

36. DIVERGENT AND TRANFORM BOUNDARIES
SEPTEMBER 1

37. FALCON FOCUS
With reference to the types of crusts, describe how converging boundaries are formed.

38. ESSENTIAL QUESTION
WHAT LANDFORMS RESULT FROM A DIVERGENT BOUNDARY?

39. Landforms from Convergent Boundaries
Deep ocean trench – includes oceanic and continental plates; as oceanic subducts, it pulls the front edge of the continental plate.
Volcanoes – includes oceanic and continental; continental plate melts due to friction and extreme heat; melted plate rises up through crust and cools when it reaches surface
Volcanic island arc- includes only oceanic plates; subduction occurs
Folded mountains – includes only continental plates; collision occurs; no subduction

40. PEER/PAIR ASSIGNMENT
To your favorite Rap beat, compose a lyric to describe the types of boundaries (convergent, divergent and transform). You will be graded on content, creativity and performance. Presentation – tomorrow Lyrics MUST be typed!!!

41. Divergent Boundaries
The place where two plates move apart—or diverge—is called a divergent boundary
Most divergent boundaries occur at the mid-ocean ridge—so crust is forming
When divergent boundaries occur on land, a rift valley is formed

42. Divergent Boundaries  
A plate boundary where two plates move away from each other.
 
RIFTING
causes
SEAFLOOR SPREADING

43. How is the rock pulled at Divergent Boundaries
How is the rock pulled at Divergent Boundaries? Rock gets THIN in the middle as it is pulled apart. This STRESS is called

44. What happens when the rock SNAPS from the Stress of Tension
What happens when the rock SNAPS from the Stress of Tension? A Normal Fault (fault is a break in Earth’s crust) Rock drops down as it breaks

45. What happens next at Divergent Boundaries?
A geologic feature or event…
May form RIFT VALLEYS on continents
SEA-FLOOR SPREADING in the ocean

46. Helpful Hints… Divergent is like “dissecting” or “dividing”
If you pull warm bubble gum or silly putty, it will thin in the middle until it is stressed so much that it breaks.
Happens on land
& under H2O

47. Features of Divergent Boundaries
Mid-ocean ridges
rift valleys
fissure volcanoes

48. TRANSFORM BOUNDARY
SEPTEMBER 2, 2016

49. FALCON FOCUS
Can you match the boundary name correctly with its diagram?
_____________

50. ESSENTIAL QUESTION
WHAT LANDFORMS RESULT FROM A TRANSFORM BOUNDARY?

51. Transform Boundaries
Along transform boundaries crust isn’t created or destroyed
At a transform boundary the two plates slip past each other

52. Transform Boundaries
A plate boundary where two plates move past each other in opposite direction.

53. How is the rock broken at Transform Boundaries?
Rock is pushed in two opposite directions (or sideways, but no rock is lost)
This stress is called SHEARING

54. What happens next at Transform Boundaries?
May cause Earthquakes when the rock snaps from the pressure.
A famous a Transform Boundary is the San Andreas Fault in California.

55. San Andreas Fault, CA

56. What happens when the rock is sheared (or “cut”) from the Stress of Shearing?
A STRIKE-SLIP FAULT
Rocks on each side of the fault slip past each other as they break.

57. Helpful Hints…
Shearing means cutting (“Shears” are like scissors)
Transform boundaries run like trains going past each other in different directions & they shake the ground!

58. Plate Boundaries:
Correct Answers:
Divergent
Convergent
Transform

59. Station Work WHAT IS THE THEORY OF PLATE TECTONICS?
WHAT IS A RIFT VALLEY? HOW IS IT FORMED?
WHAT TYPES OF PLATE MOVEMENT OCCUR AT PLATE BOUNDARIES
WHAT MAJOR EVENT BEGAN ABOUT 225 MILLION YEARS AGO?
LABEL ALL THE BOUNDARIES ON FIGURE 5 (OVERHEAD) AS TRANSFORM, CONVERGENT OR DIVERGENT.