1. Bell work 11/16
Get a computer
Open quizlet
Practice vocabulary set 5

2. QUICK REVIEW… Layers of the Earth
Crust (2 types)
Mantle
Outer Core
Inner Core
Earth’s crust & the very top solid portion of the mantle form the lithosphere
The lithosphere sits on top of the liquid asthenosphere

3. HOW???

4. LAW OF UNIFORMITARIANISM
Law of Uniformitarianism: States that Earth is an always changing place
The same forces of change are at work today that were at work in the past.
Some changes are gradual; some changes are fast…some times both!

5. SINKHOLES
Would you categorize them as a fast change, a slow change, or both?
They seem to be getting more common…WHY?

6. SOME THINGS HAPPEN SLOWLY, WHILE OTHERS HAPPEN QUICKLY, BUT WHAT THEY BOTH HAVE IN COMMON IS A LOT OF THEM STEM FROM MOVEMENT …BUT MOVEMENT OF WHAT????
HINT:

7. TECTONIC PLATES
The Lithosphere is broken into many large and small slabs of rock called tectonic plates and where two plates meet, a lot of changes can occur.

8. How do the tectonic plates move?
The plates move because of convection currents.
The hot, soft rock in the mantle rises…then it cools, and sinks.
How do the tectonic plates move?

9. There are 3 types of plate boundaries
TECTONIC PLATES
1. Divergent
2. Convergent
3. Transform
There are 3 types of plate boundaries

10. SUBDUCTION What is SUBduction?
When one tectonic plate sinks under another plate
IT CAN ONLY HAPPEN WHEN…
Continental & oceanic plate collide = oceanic plate ALWAYS sinks because it is more DENSE.
Oceanic & oceanic plate collide = the more dense plate sinks!
What is SUBduction?

11. DIVERGENT
Key word: Divide

12. DIVERGENT

13. DIVERGENT Mid-ocean Ridges Rift Valleys Earthquakes
What occurs at this boundary?
New Crust Forms
Mid-ocean Ridges
Rift Valleys
Earthquakes

14. REAL-WORLD EXAMPLES : Divergent Boundary
Mid-Ocean Ridges like the Mid-Atlantic Ridge

15. CONVERGENT Key word: Collide 3 types of convergent:
Continental-continental
Oceanic-oceanic
Oceanic-continental

16. CONVERGENT: CONTINENTAL-CONTINENTAL

17. CONVERGENT: CONTINENTAL-CONTINENTAL
What occurs at
this boundary?
High mountains
Earthquakes

18. REAL-WORLD EXAMPLES: Continental-Continental Convergent
High Mountains like the Himalayas

19. CONVERGENT: OCEANIC-OCEANIC

20. CONVERGENT: OCEANIC-OCEANIC
What occurs at this boundary?
Deep-ocean Trenches
Volcanic Islands
Earthquakes
Hawaii is NOT on a plate boundary!

21. REAL-WORLD EXAMPLES: Oceanic-Oceanic Convergent
Deep-ocean trenches like the Mariana Trench

22. CONVERGENT: OCEANIC- CONTINENTAL

23. CONVERGENT: OCEANIC-CONTINENTAL
What occurs at this boundary?
Deep-ocean trenches
Coastal mountains (some are volcanic)
Earthquakes

24. REAL-WORLD EXAMPLES: Continental-Oceanic Convergent
Coastal mountains like the Andes Mountains on the coast of South America

25. TRANSFORM
Key word: Slide

26. TRANSFORM

27. TRANSFORM
What occurs at this boundary?
Faults
Earthquakes

28. REAL-WORLD EXAMPLES: Transform Boundary
Faults, like the San Andreas Fault in California

29. PLATE MOTION SIMULATION
Simulation of the tectonic plate movement we talked about today!

30. QUICK REVIEW

31. Draw and label the 4 main layers of the Earth:
ESSENTIAL QUESTIONS
Draw and label the 4 main layers of the Earth:
What are the 2 type of crust?

32. Explain why the Earth’s interior is separated into these layers:
ESSENTIAL QUESTIONS
Explain why the Earth’s interior is separated into these layers:
DENSITY

33. ESSENTIAL QUESTIONS
If it is so hot, why is the inner core solid?
Because it is under so much intense PRESSURE from the other layers sitting on top of it.

34. Which 2 layers make up the lithosphere?
ESSENTIAL QUESTIONS
Which 2 layers make up the lithosphere?
Which layer does the lithosphere sit on top of?
Crust
Mantle (solid upper portion)
Asthenosphere

35. Which layer is broken into tectonic plates?
ESSENTIAL QUESTIONS
Which layer is broken into tectonic plates?
What are the 3 types of tectonic plate boundaries?
Lithosphere
Convergent, Divergent, Transform

36. ESSENTIAL QUESTIONS
What is the key word that goes with each type of boundary that indicates the type of movment?
Convergent = Collide
Divergent = Divide
Transform = Slide

37. What is it called when one plate sinks beneath another?
ESSENTIAL QUESTIONS
What is it called when one plate sinks beneath another?
Which plate will sink?
Subduction
The denser plate/oceanic

38. What event occurs at all plate boundaries?
ESSENTIAL QUESTIONS
What event occurs at all plate boundaries?
At which type of plate boundary will any mountains occur?
Earthquakes
Convergent

39. ESSENTIAL QUESTIONS
If new crust is created at divergent boundaries, then why doesn’t Earth get any bigger?
SUBDUCTION! As new crust is formed at a divergent boundaries, old crust is being melted down at convergent boundaries where subduction is occurring. New crust is being “created” at the same rate that old crust is being “destroyed.”
Earth recycles itself!

40. PLATE TECTONICS REVIEW
Please turn to your note guide from last class so you can reference it during the mini lab activity!

41. REMEMBER…
It is the movement of the tectonic plates that cause the majority of changes on Earth.
Some changes happen quickly, while others happen slowly, but none have been more Earth changing than this…
HOW?

42. PANGAEA
Scientist Alfred Wegener noticed that Earth’s continents seemed to fit together like a puzzle, so he hypothesized that they were once joined in a single “super continent” called Pangaea
which means “all land”

43. 255 MILLION YEARS AGO

44. 152 MILLION YEARS AGO

45. 66 MILLION YEARS AGO THE EXTINCTION OF THE DINOSAURS

46. PRESENT DAY POSITION

47. 50 MILLION YEARS FROM NOW

48. 150 MILLION YEARS FROM NOW

49. 250 MILLION YEARS FROM NOW

50. CONTINENTAL DRIFT
This led to his Theory of Continental Drift – that although the continents were once joined, they slowly drifted apart!
But nobody believed him ☹…why?
Wegener’s Evidence:
1. Matching rock layers on different continents
2. Matching fossils on different continents
3. Evidence of climate change – tropical plant fossils in cold places, ice scratches in warm places

51. SEA-FLOOR SPREADING http://www.youtube.com/watch?v=GyMLlLxbfa4
Harry Hess’ discovery turned the Theory of Continental Drift into the Theory of Plate Tectonics!

52. SEA FLOOR SPREADING
The sea floor spreads apart at divergent boundaries allowing new crust to form…this new crust builds Mid-Ocean ridges
The crust closest to the crack is the youngest while the crust further from the crack is older

53. MAGNETIC REVERSALS
Minerals in the magma that rise through the cracks in the sea floor align themselves with Earth’s magnetic poles (North and South)
As the rock cools, the minerals stay fixed in this position, like a compass
Earth’s poles periodically reverse. The “stripes” of rock along the ocean floor record these reversals.

54. QUICK REVIEW What is the former “supercontinent” called?
Why is it called Pangaea?
The idea that the continents had slowly moved is called…?
Who was the scientist that proposed the idea of both Pangaea & Continental Drift?
Why didn’t people believe him?
What did he use as evidence to prove his theory?
What LAND FORM was later discovered on the ocean floor that supported his theory?

55. QUICK REVIEW How is this land form created?
This discovery turned the Theory of Continental Drift into the Theory of…?
We further discovered that the oldest crust was located…?
And the youngest crust was located…?
Not only were there age patterns, but patterns of what else?
Which scientist is responsible for the discovery of the Mid-Ocean Ridge & Sea- Floor Spreading?

56. TECTONIC PLATE MAP ANALYSIS

57. HOT SPOTS!
Read Hawaii…How?

58. HOT SPOTS! – Reading Comprehension
What is the Earth’s lithosphere made up of?
Where can a volcano form?
What plate are the Hawaiian Islands on?
Are they at a plate boundary or a hot spot?
What is a hot spot?
Does a hot spot move?
So what is moving?
How many islands has this hot spot formed to make the Hawaiian Island chain?
Where are there other hot spots?

59. HOT SPOT VIDEOS – Discovery Education
Hot Spots: The Formation of the Hawaiian Islands
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Yellowstone’s Super Volcano: A Ticking Time Bomb
Guid/2CE8482D-877D-48D3-A9BB-9A03A86321DA

60. HOT SPOTS Hot spots occur far from plate boundaries.
Magma rises and eventually melts through the crust above it.
The plate moves, but the hot spot stays in the same place - creates a series of volcanic islands or volcanoes.
Hot spots help measure plate movement.

61. Conclusion Plate Tectonics & Continental Drift
“CONTINENTS ADRIFT”
Conclusion Plate Tectonics & Continental Drift

62. Law of Uniformitarianism Tectonic Plates Subduction Divergent Boundary
KEY VOCABULARY TERMS FOR THIS POWERPOINT…BUT DON’T FORGET THE ROCK CYCLE WORDS!!!
Crust
Mantle
Outer Core
Inner Core
Lithosphere
Asthenosphere
Convection Current
Magma/Lava
Law of Uniformitarianism
Tectonic Plates
Subduction
Divergent Boundary
Convergent Boundary
Transform Boundary
Mid-Ocean Ridge
Rift Valley
Deep-ocean Trench
Pangaea
Continental Drift
Sea floor Spreading
Magnetic Reversal
Hot Spot