1. Joints vs. Faults

2. Diastrophism Deformation of the earth’s crust due to plate movement
Landforms that are created when
plates collide or separate are caused by diastrophism

3. No displacement of layers after cracking
Columnar Joints
No displacement of layers after cracking

5. Fractures in bedrock in which movement HAS taken place
Faulting
Fractures in bedrock in which movement HAS taken place

6. Earth’s Plate Boundaries follow Fault Lines

7. New Madrid Zone is a fault line that is an ancient plate boundary

8. Fault or Joint?

12. Hanging Wall
Footwall

13. Let’s look at those again & determine the Footwall and Hanging Wall

14. A B

15. A B

16. B A

17. A B MC

18. Strike & Dip
Dip

19. Dip refers to the angle at which a fault plane DIPS into the earth’s crust

20. This is a dip…

21. This is also a dip…

22. This is taking a dip…

23. This is definitely a dip…

24. Dip-Slip Faults

25. Slickenlines are fine scratches & show direction of slip…
Normal Dip-Slip Fault
Slickenlines are fine scratches & show direction of slip…

26. In a Normal Dip-Slip Fault the Hanging Wall has moved DOWN relative to the footwall

27. Reverse Dip-Slip Fault

28. Reverse Dip-Slip faults are often referred to as THRUST faults because they are cause by compression forces. The Footwall acts likes a wedge…

29. In Reverse Dip-Slip the Hanging Wall has moved UP relative to the footwall

30. Strike is the compass direction where the fault meets the surface
Strike & Dip
Strike is the compass direction where the fault meets the surface

31. Strike-Slip Faults
AKA: Lateral Fault

32. Caused by SHEAR forces

33. The San Andreas Fault is a Lateral or Strike-Slip Fault

34. Oblique-Slip Faults Caused by tension forces Divergent Plate Boundary

35. Graphics showing RIFTING

37. Africa is being slowly torn apart by rifting and Oblique faults…

38. Oblique-Slip Fault

39. Rifting can lead to sea floor spreading as can be seen in the Mid-Atlantic Ridge. This is technically an Oblique Fault

40. Ok, now it’s time to identify faults Normal Dip-Slip Reverse Dip-Slip Strike-Slip Oblique-Slip

42. That was a Normal Dip-Slip!

44. You’re good. That was a Strike-Slip Fault…

46. That was an Oblique-Slip Fault… Did you get it?

48. Yup. That was another Normal Dip-Slip (As opposed to an ABNORMAL one )

50. So, did you call that one a Reverse Dip-Slip? You’re right!!

52. That was certainly another Reverse Dip-Slip

54. You called it… Reverse Dip-Slip

56. Strike-Slip…

58. Reverse Dip-Slip…

60. Enough of the Strike-Slip Faults already!