Download CH. 8 Review WS 2

Earth Science
Name:
Chapter Eight--Worksheet Review # 2
Class Period:
Section Two and Three: [Pages 202-210]
Directions: Use your textbook and notes to assist you with answering the following questions.
1. Seismologists want to find out which of the following things about an earthquake? (More than one answer possible.)
a. when it started
c. how far it traveled
b. where it started
d. how strong it was
e. how much the ground moved
2. Seismographs create tracings of earthquake motion called
.
3. How do seismologists determine when an earthquake started?
4. The
of an earthquake is the place deep within the Earth where an earthquake begins.
(epicenter or focus)
5. The
of an earthquake is on the surface of the Earth above where an earthquake begins.
(epicenter or focus)
6. What is the name of the method seismologists use most to find the epicenter of an earthquake?
a. the P-S method c. the P-S time method
b. the S-P method d. the S-P time method
7. Look at the diagram at the bottom of page 203. Once the seismologists know how far an epicenter is from a certain
seismograph station, how do they find the location of the epicenter?
8. Who is interested in the strength of earthquakes and where they originate?
9. On the modified Richter scale shown on page 204, an earthquake with a magnitude of
causes damage at the epicenter.
10. An earthquake with a magnitude of 10 would release 31.7 times as much energy as an
earthquake with a 11 magnitude of 6.0.
11.
12. What does a seismologist study to determine the earthquake hazard level for a particular area?
13. Mark each of the following statements True or False.
a. It is difficult to predict when earthquakes will occur.
b. The strength of earthquakes varies with how often they occur.
c. If an area has strong earthquakes, it never has weaker earthquakes.
14. In your own words, explain how seismic gaps relate to the gap hypothesis.
15. What scale is used to measure the energy released by earthquakes?
Write true if the statement is true. If the statement is false, change the underlined term to make the statement true. Write your
answers in the spaces provided.
16. An instrument that detects and measures earthquakes is a seismic wave.
17. The place inside the earth where an earthquake starts is called a focus.
18. The place on the Earth’s crust directly above the place where an earthquake starts is called
the focus.
19. Vibrations released during an earthquake are called focus waves.
20. The higher the lines on a seismogram, the weaker the earthquake.
21. A tsunami forms when the epicenter of an earthquake is on the desert floor.
22. A tsunami is a large wave that is sometimes caused by an earthquake.
23. The San Andreas Fault is a strike-slip fault that runs through portions of California.
24. The force of tension at a divergent plate boundary causes a minor earthquake.
25. Most destruction in an earthquake is caused by p-waves .
26. Use the listed terms to label the diagrams. Write your answers in the provided spaces.
27. When the buildup of stress in Earth’s crust is so great that rocks reach their (elastic limit,
tectonic force), an earthquake occurs.
28. A reverse fault is often located along a (divergent, convergent) plate boundary.
29. The radius of the circle seismologists draw on a map is equal to the distance from a
station to an earthquake’s (epicenter, fault line)
30. The slowest seismic waves are (primary, secondary) waves.
31. The farther apart primary, secondary, and surface waves are, the (closer, farther away) the
epicenter is.
32. (Compression, Tension) forces are generated at convergent plate boundaries.