Chapter 12 Study Notes

1. Chapter 12 Study Notes Earthquakes

2. 1 • A ____ wave is a seismic wave that travels through the _____ of the earth. • body • interior

3. 2 • A _______ is a small earthquake that may precede a ______ earthquake. • foreshock • larger

4. 3 • A modern _______ consists of _____ sensing devices. • seismograph • three

5. 4 • A ______ ______ is an area in which strong earthquakes have occurred in the ______. • seismic • gap • past

6. 5 • A ______ displays earthquake motion ________ by a seismograph. • seismogram • recorded

7. 6 • A _______ is an instrument that records the ground _______. • seismograph • vibrations

8. 7 • A __________ is an area where no direct ______ _____ from a particular earthquake can be detected. • shadow zone • seismic • waves

9. 8 • A ______ wave is a seismic wave that travels along the _______ of the earth. • surface • surface

10. 9 • A ______ is a large ocean _____ that forms after a volcanic eruption, underwater earthquake, or landslide. • tsunami • wave

11. 10 • As tsunamis move toward shore the waves _______ in _____. • increase • height

12. 11 • Before and after an earthquake you should stay _______ and follow ________. • cautious • instructions

13. 12 • During a _____ earthquake, buildings may _____ or _______. • major • sway • collapse

14. 13 • Earth’s interior affects the _____ and _______ of seismic waves. • speed • direction

15. 14 • Earthquake _______ is _________. • prediction • unreliable

16. 15 • Earthquakes generally occur at _____ _______ where stress on rocks is the ________. • plate • boundaries • greatest

17. 16 • _______ ________is the ______ return of deformed rock to its ________ shape. • Elastic • rebound • sudden • undeformed

18. 17 • If you are ______ during an earthquake, you should crouch under _____. • indoors • desk

19. 18 • _____ is the amount of _______ caused by an earthquake. • Intensity • damage

20. 19 • Intensity ____ on the modified Mercalli scale is described as causing _____ __________. • XII • total • destruction

21. 20 • ________ is a measure of the ______ of an earthquake. • Magnitude • strength

22. 21 • P _______ are the ______ body waves. • waves • fastest

23. 22 • P waves can travel through ______, ______, and _______. • solids • liquids • gases

24. 23 • P waves travel _______ through very _____ and not easily _______ materials. • fastest • rigid • compressed

25. 24 • S waves can only travel through ______. • solids

26. 25 • Scientists find the _______ of an earthquake by comparing the ______ times of P waves and S waves at _____ or more seismograph stations. • epicenter • arrival • three

27. 26 • Scientists study ______ ______, ____ ______, and _______ in order to predict earthquakes. • seismic • gaps • rock • changes • foreshocks

28. 27 • The _______ of an earthquake is the point on Earth’s _______ directly above the earthquake’s focus. • epicenter • surface

29. 28 • The ______ ______ of an earthquake occurs at the _____. • first • motion • focus

30. 29 • The _______ _______ scale measures the _________ of an earthquake. • modified • Mercalli • intensity

31. 30 • The moment magnitude scale measures the ________ of an earthquake by the _____ size and the ______ that the fault blocks move. • magnitude • fault • distance

32. 31 • The _______ _______ scale measures the ________ of large earthquakes the most ________. • moment • magnitude • magnitude • accurately

33. 32 • The Richter scale is based on ________. • magnitude

34. 33 • The Richter scale measures the _____ of an earthquake using ______ ______. • magnitude • ground • motion

35. 34 • _______ _______, ________, and undersea ________ may all cause a tsunami. • Volcanic • eruptions • earthquakes • landslides

36. 35 • When seismologists record ______ times of P waves and S waves at three or more seismograph stations, they are looking for the earthquake’s ________. • arrival • epicenter

37. 36 • You can prepare for an earthquake by gathering _____, _____, _______, and a portable _____. • food • water • flashlights • radio

38. The End