1. Diastrophism Results of plate tectonics: 1.volcanism2.diastrophism3.earthquakes

2. diastrophism: Deformation of crust due to tectonic stress: Deformation of crust due to tectonic stress: Folding (bending)Folding (bending) Faulting (breaking and displacement)Faulting (breaking and displacement)

3. Types of Stress and Strain (Stress is force acting on rock; strain is rock’s response to stress) Compression (shortening) Compression (shortening) Extension (stretching) Extension (stretching)

4. EXTENSION COMPRESSION

6. Folding Compressional stress causes rocks to buckle and fold Compressional stress causes rocks to buckle and fold Anticline: arch-shaped foldAnticline: arch-shaped fold Syncline: sink-shaped foldSyncline: sink-shaped fold

7. Anticlines begin as ridges ; synclines begin as valleys. Anticlines begin as ridges ; synclines begin as valleys.

8. Differential erosion leads to: Differential erosion leads to: Anticlinal ridges and valleysAnticlinal ridges and valleys Synclinal ridges and valleysSynclinal ridges and valleys Differential erosion: less-resistant types of rock strata will weather and erode more rapidly than more-resistant rock strata Differential erosion: less-resistant types of rock strata will weather and erode more rapidly than more-resistant rock strata

9. Anticlinal mountain/ridge Synclinal valley

10. What’s this? Synclinal mountain/ridge

12. Faulting Rock is strained beyond ability to remain intact; rock fractures; one side is displaced with respect to the other. Rock is strained beyond ability to remain intact; rock fractures; one side is displaced with respect to the other. Fault plane: surface along which 2 sides moveFault plane: surface along which 2 sides move Fault scarp: cliff formed along fault faceFault scarp: cliff formed along fault face

14. Fault from Hebgen Lake, Montana earthquake, 1959 What’s this? Fault scarp

15. Types of Faults 1. Normal Fault: from extensional stress Vertical movement along an inclined fault plane

17. normal

19. Horst and Graben (result of normal faulting) Horst : up- faulted block Graben: down- faulted block

22. Block mountains

23. 2. Reverse Fault from compressional stress Vertical movement along inclined fault plane such that one side rides up over the other. often creates landslides

26. reverse

27. reverse

28. reverse

29. 3. Overthrust fault Reverse fault with very low angle Reverse fault with very low angle More horizontal than vertical movement More horizontal than vertical movement

30. overthrust

31. 3. Transcurrent (Strike-slip) Fault horizontal movement no fault scarp

33. Transcurrent

34. Transcurrent HEY! Who moved my wood pile?!@*

35. Transcurrent

36. San Andreas