Study Guide – Exam II – Fall 2003

1. Can you identify a great circle on a stereonet?

2. Can you identify a small circle on a stereonet?

3. Can you plot the attitude of a plane on a stereonet?

4. Can you plot the pole to a plane on a stereonet?

5. Can you plot the attitude of a line on a stereonet?

6. Given the following data, can you solve for the attitude of the axial surface and hingeline, and the interlimb angle?  Limb1: N30W, 60NE. Limb2: NS, 40 W.  Ans: N16W, 80SW; 6 at N21W; 84 degrees

7. Can you fully classify the fold described in 6? Ans: plunging, upright, open fold

8. Given the following data, can you solve for the attitude of the axial surface and hingeline, and the interlimb angle? Limb1: N40E, 80SE. Limb2: N60W, 50NE. Ans: N74E, 71NW; 48@N51E; 89 degrees

9. Can you fully classify the fold described in 8? plunging, open, upright

10. Given the following data, can you solve for the attitude of the axial surface and hingeline, and the interlimb angle? Limb1: N20W, 80SW. Limb2: N30E, 40SE. Ans: NS, 69E; 30@S20E; 74 degrees?

11. Can you tell me how a profile view of a fold might differ from a cross-sectional view?

12. Given a cross-section striking N50W, and a bedding attitude of NS, 40W, what is the apparent dip of the bed in the plane of the cross-section?  Ans: 32 NW

13. Given an anticline with a hingeline attitude of 40 @ N20W, and a bedding attitude on the SW limb of N23E, 50NW, what is the pitch of the bed in the plane of the profile of the fold?  Ans: 34 SW?

14. Can you tell me what you might look for as evidence of faulting in the field?

15. Can you tell me what the xenith point is and how it is used in the construction of a stereonet?

16. Can you tell me how a symmetric fold differs from an asymmetrical fold?

17. Can you tell me what the hingeline of a fold is?

18. Can you tell me what the axial surface of a fold is?

19. Can you tell me how the map pattern for a plunging syncline would differ from that of a non-plunging syncline?

20. Can you tell me how the map pattern for a plunging anticline would differ from that of a non-plunging anticline?

21. Can you explain to me how you would determine the direction of plunge of an anticline from a geologic map of such a structure?

22. Can you explain to me how you would determine the direction of plunge of a syncline from a geologic map of such a structure?

23. Can you recognize the map pattern of a doubly plunging anticline?

24. Can you recognize the map pattern of a doubly plunging syncline?

25. Can you tell me what the words culmination and depression refer to?

26. Can you tell me how a similar fold differs from a parallel fold?

27. Can you describe for me the triangulation method that you would use in the field to locate yourself on a topographic map?

28. Can you tell me what the following terms refer to: microscopic, mesoscopic, macroscopic?

29. Can you tell me what the orthographic projection plane is?

30. Can you list in ascending or descending order the Eonothems/Eons, Eratherms/Eras, and Systems/Periods of the geologic column?

31. Can you plot and recognize the key elements of a fold on a geologic map, e.g., trace of axial surface, attitude of hingeline, type of fold?

32. Can you sketch for me a dextral (right-lateral) sense asymmetric fold?

33. Can you sketch for me a sinistral (left-lateral) sense asymmetric fold?

34. Can you tell me how you would determine the asymmetry of a fold in the field?

35. Can you recognize the map pattern of plunging and non-plunging folds?

36. If you were exploring for hydrocarbon accumulations can you tell me what kind of fold (anticline or syncline) you would search for?

37. Can you explain to me the mechanism of flexural-slip folding?

38. Can you define a cylindrical fold?

39. Can you define a non-cylindrical fold?

40. Can you tell me what a generator line is?

41. Can you describe for me the difference between a disharmonic and harmonic fold?

42. Can you draw a cross-section across a fold and accurately project into the plane of the cross-section the geometry of the fold?