1. Earthquake Review

2. What is one similarity between P and S waves
They both travel through solids
They both start at a focus
Both begin at the same time
Both can be felt at Earth’s surface

3. Answers will vary

4. What is another similarity between P and S waves?

5. Answers will vary

6. What does a wave’s speed depend on?

7. The density of a medium
What kind of medium it is traveling through

8. What is a fault?

9. A break or crack in the Earth’s crust

10. What is refraction?

11. The bending of a wave as it travels through a boundary

12. Do earthquakes always cause destruction?

13. Nope

14. How many earthquakes occur each year felt by humans?

15. Thousands

16. How many earthquakes occur each year only felt by seismographs?

17. Millions

18. Draw a picture of a reverse fault.

20. What is one difference between P and S waves?
P waves travel through liquids and S waves do not
P waves are a push and pull motion while S waves are a side to side motion
P waves travel faster than S waves
P waves will reach a seismograph before S waves
S waves cause more destruction than P waves

21. Answers will vary

22. What is another difference between P and S waves?

23. Answers will vary

24. What is the difference between the epicenter and focus?

25. Focus – point inside the Earth where an earthquake begins Epicenter – point on Earth’s surface above focus

26. What is a seismograph?

27. An instrument that records vibrations in the ground and determines the location and strength of an earthquake

28. Do earthquakes release energy?

29. Yep

30. What causes earthquakes to occur?

31. Tectonic plates move past each other causing stress (The movement of tectonic plates)

32. What are the waves of energy that travel through the Earth called?

33. Seismic Waves

34. Draw a picture of a normal fault.

36. What are the 2 scales used to measure earthquake strength?

37. Richter Magnitude Scale
Mercalli Intensity Scale

38. Where do most earthquakes occur?

39. At or near plate boundaries

40. Draw a picture of a strike-slip fault.

42. What is the difference between the Mercalli and Richter scales?

43. Mercalli Scale measures the strength of shaking and how much damage was caused to a city
Richter Magnitude Scale measures the amount of energy released and what shows up on a seismogram

44. If you know the distance from the epicenter of an earthquake to 3 seismic stations how could you find where the earthquake originated?

45. Draw a circle around each city with the radius being the distance away from the epicenter the city is. Once all three circles are drawn where they overlap is where the earthquake originated.

46. Where in the united states experiences the most earthquakes and why?

47. California because it is on a fault (plate boundary)

48. If you had the intensity level of different cities how could you tell where an earthquake started?

49. It started where the highest intensity levels are

50. In what direction(s) do earthquakes release waves?

51. All directions

52. What is the connection between earthquake strength and occurrence?

53. Weaker earthquakes occur more often than stronger earthquakes

54. What is a seismogram?

55. A tracing of earthquake motion that is created by a seismograph

56. What kind of deformation leads to earthquakes occurring?

57. Elastic Deformation

58. Why does Ohio not experience many earthquakes?

59. We are not on a plate boundary (or fault)

60. What is the S-P time interval of the following printout?

61. 49 Seconds