1. Effects of Plate Tectonics Part I
Forces Shape the Land

2. Definition: Isostasy
When plates move, they balance to equilibrium on athenosphere
Example: Drop block in water, and it bobs up & down, then floats

3. Major Forces Stress/Strain: Compression, Shearing, Tension
Folding/Deformation: Anticline, Syncline, Monoclines (Rocks don’t break)
Faulting: Normal, Reverse, Strike-Slip (Rocks do break)
These forces can create:
1) Landform changes
2) Mountains
3) Earthquakes
4) Volcanoes

9. types of folds
Anticline – “A” Shaped

10. types of folds
Syncline – remember “smile” shaped

11. types of folds
Monocline – slightly curved

12. Folds Animation Link

13. fault terminology
                                                    
Fault – fracture in rock along which there has been displacement
Hanging wall – rock surface above the fault
Footwall – rock surface below the fault
Fault scarp – exposed fault surface

14. Caused by tension forces Hanging wall moves down
Normal Faults
Caused by tension forces
Hanging wall moves down

20. Reverse Faults
Caused by compression forces
Hanging wall moves up

25. Opposing forces cause rock to break
Strike-slip Faults
Opposing forces cause rock to break
Move horizontally

34. Animation Link:

35. Questions for Review What is isostasy?
Explain the difference among compression, shearing, and tension.
What is the difference between a fold and a fault?
Name the 3 types of folds and their shape.
What are the 3 types of faults?
What are some effects of plate tectonics?

36. CE Questions
As a volcanic mountain range is built, isostatic adjustment will cause the crust beneath it to:
A) Break
B) Sink
C) Rise
D) Fold

37. CE Questions
As a volcanic mountain range is built, isostatic adjustment will cause the crust beneath it to:
A) Break
B) Sink
C) Rise
D) Fold

38. CE Questions
Isostatic adjustments continue until the forces pressing the crust up and down are:
A) Balanced
B) Doubled
C) Decreased
D) Removed

39. CE Questions
Isostatic adjustments continue until the forces pressing the crust up and down are:
A) Balanced
B) Doubled
C) Decreased
D) Removed

40. CE Questions
Folding of rocks is most likely to happen when rocks undergo:
Tension
Shearing
Compression
Cooling

41. CE Questions
Folding of rocks is most likely to happen when rocks undergo:
Tension
Shearing
Compression
Cooling

42. CE Questions
Rocks deeper in the earth’s crust are less likely to deform by breaking than rocks closer to the earth’s surface because of:
A) Lower stresses
B) Higher temperature
C) Higher strains
D) Lower altitude

43. CE Questions
Rocks deeper in the earth’s crust are less likely to deform by breaking than rocks closer to the earth’s surface because of:
A) Lower stresses
B) Higher temperature
C) Higher strains
D) Lower altitude

44. CE Questions Which causes reverse faults? A) Compression B) Shearing
C) Tension
D) Folding

45. CE Questions Which causes reverse faults? A) Compression B) Shearing
C) Tension
D) Folding

46. CE Questions Where do strike-slip faults often occur?
A) At mid-ocean ridges
B) In the lower half of the crust
C) Between ridges
D) Along transform plate boundaries

47. CE Questions Where do strike-slip faults often occur?
A) At mid-ocean ridges
B) In the lower half of the crust
C) Between ridges
D) Along transform plate boundaries

48. CE Questions
Explain the cause and effect of normal, reverse, and strike-slip faults (be specific).

49. CE Questions
What is the result of a….convergent boundary….divergent boundary…transform…?
Which produces new crust?
Which takes place on continental crust?
Which takes place in the ocean?
Which boundary is located in California?

50. Discovery Ed Videos