Chapter 19 Review

1. Chapter 19 Review Earthquakes

2. Movement occurs along fractures in rocks when _____. • stress equals the strength of the rocks involved • stress overcomes the strength of the rocks involved • stress is applies to the rocks involved • stress is less than the rocks involved

3. The strain which causes a material to twist is known as • stress • compression • tension • shear

4. The strain which causes a material to pull apart is known as • stress • compression • tension • shear

5. P-waves and S-waves are also known as ____. • surface waves • ground waves • body waves • first waves

6. Which point marks the epicenter of the earthquake? • A • B • C • D

7. At which point will the most damage as a result of the earthquake occur? • A • B • C • D

8. What is true about the focus? • It is the point where the most surface damage will occur. • It is the point where the surface waves originate and spread out. • It is the point where the waves are attracted. • It is the point of failure where the waves originate.

9. What keeps the stable part of this seismometer from moving during an earthquake? • inertia • gravity • its mass • its location

10. Which part of the seismometer does not shake during an earthquake? • the frame • the spring • the rotating drum • the pendulum and pen

11. Use the graph to answer the questions.

12. A seismogram is located 4500 miles away from the epicenter of an earthquake. What is the difference in time between when the P-waves reach the seismogram and the S-waves reach the seismogram? • 5 1/2 minutes • 6 minutes • 10 minutes • 22 minutes

13. Which type of material would be best to use for construction in an area prone to earthquakes? • Concrete • Brick • Wood • Stone

14. Organize the locations from lowest to highest hazard. • B, A, D, C • C, D, A, B • A, B, C, D • B, A, C, D

15. Seismologists have assessed a particular area and predict that an earthquake occurs every 17 years in that area. If the last earthquake occurred in 1998, when will the next earthquake most likely occur? • 2010 • 2015 • 2017 • 2025

16. Over the past 250 years a city has experienced 23 earthquakes at rather regular intervals. Approximately how often have these earthquakes occurred? • every 50 years • every 10 years • every 100 years • every 5 years

17. A city is located over an active fault, but has not experienced an earthquake for a long period of time. The city is most likely located where? • over a seismic gap • in an area of low recurrence • over minimal strain accumulation • at a location of low seismic risk

18. ____ and the amount of strain released during the last quake are used in earthquake probability studies. • Seismic belts • Strain accumulation • Fault scarps • Tsunamis

19. On a seismometer, vibrations of the ground do not move the ____. • frame • spring • recording drum • suspended mass

20. A ____ fault forms as a result of horizontal compression. • blind • normal • strike-slip • reverse

21. The San Andreas Fault, a result of horizontal shear, is a ____ fault. • blind • normal • strike-slip • reverse

22. The locations of seismic belts are determined by plotting ____. • earthquake epicenters • seismic gaps • earthquake foci • epicentral distances

23. A numerical scale of earthquake magnitude that takes into account the size of the fault rupture is the ____. • Richter scale • modified Mercalli scale • moment magnitude scale • epicentral distance scale

24. Deaths associated with earthquake deaths in sloping areas can result from • tsunamis. • landslides. • formation of fault scarps. • surface ruptures.

25. Does not pass through Earth’s liquid outer core • surface wave • P-wave • S-wave

26. Does not pass through Earth’s interior at all • surface wave • P-wave • S-wave

27. Squeezes and pulls rocks in same direction as the save travels • surface wave • P-wave • S-wave

28. Is refracted by Earth’s core • surface wave • P-wave • S-wave

29. Absence of this kind of waves results in a shadow zone • surface wave • P-wave • S-wave

30. Causes structures to sink into the ground • Liquefaction of soils • Collapse of higher, intact floors onto ground floors • Vertical motions of the seafloor during an earthquake • Natural sway of intermediate buildings equals the period of vibration of the earthquake

31. Type of structural failure called “pancaking” • Liquefaction of soils • Collapse of higher, intact floors onto ground floors • Vertical motions of the seafloor during an earthquake • Natural sway of intermediate buildings equals the period of vibration of the earthquake

32. Type of structural failure related to building height • Liquefaction of soils • Collapse of higher, intact floors onto ground floors • Vertical motions of the seafloor during an earthquake • Natural sway of intermediate buildings equals the period of vibration of the earthquake

33. Results in a tsunami • Liquefaction of soils • Collapse of higher, intact floors onto ground floors • Vertical motions of the seafloor during an earthquake • Natural sway of intermediate buildings equals the period of vibration of the earthquake

34. Section of an active fault that has not experienced a significant earthquake for a long time • modified Mercalli scale • magnitude • stress • fault • tsunami • strain • seismic gap • surface wave

35. Rates earthquake intensity • modified Mercalli scale • magnitude • stress • fault • tsunami • strain • seismic gap • surface wave

36. Wave generated by vertical motions of the seafloor • modified Mercalli scale • magnitude • stress • fault • tsunami • strain • seismic gap • surface wave

37. Seismic wave that causes the ground to move in two directions • modified Mercalli scale • magnitude • stress • fault • tsunami • strain • seismic gap • surface wave

38. Forces per unit area acting on a material • modified Mercalli scale • magnitude • stress • fault • tsunami • strain • seismic gap • surface wave

39. Measure of the energy released by a quake • modified Mercalli scale • magnitude • stress • fault • tsunami • strain • seismic gap • surface wave

40. Deformation of materials in response to stress • modified Mercalli scale • magnitude • stress • fault • tsunami • strain • seismic gap • surface wave

41. Fracture in rock along which movement occurs • modified Mercalli scale • magnitude • stress • fault • tsunami • strain • seismic gap • surface wave

42. Most rocks that exist in Earth’s crust are brittle but become ductile at great depths where temperatures are cooler. • True • False

43. Seismic belts are relatively narrow and tend to follow tectonic plate boundaries. • True • False

44. If two seismic stations receive data from an earthquake, the quake’s location can be computed if P-waves, S-waves, and surface waves have been received. • True • False

45. The fact that a significant earthquake has not occurred within a seismic gap indicates that an earthquake is more likely to occur in the near future. • True • False

46. On a seismometer, the suspended mass tends to stay at rest during an earthquake because of inertia. • True • False

47. A seismometer is designed so that its frame vibrates with the movement of the ground. • True • False

48. The amount of damage done to structures as a result of an earthquake is the earthquake’s magnitude. • True • False

49. S-waves are refracted, or bent, by Earth’s outer core. • True • False