Appendix F

Week Three Lab Report: Earthquakes

Answer the lab questions for this week and summarize the lab experience using this form.

|Full Name | |

|Date | |

Carefully read pages 156-170 of Geoscience Laboratory.

Complete this week’s lab by filling in your responses to the questions from Geoscience Laboratory. Select answers are provided for you in red font to assist you with your lab work. Although you are only required to respond to the questions in this worksheet, you are encouraged to answer others from the text on your own.

Lab Questions

9.1. Judging from the seismogram in Figure 9.4 of the lab book, which wave appears to be the most damaging?

Surface Wave

9.3. Determine the distance to an earthquake at a station that receives P and S waves 5.0 minutes apart. Hint: (a) Place tick marks on a scrap of paper equal to 5.0 on the minutes axis. (b) Fit that to the horizontal separation between P and S curves. (c) Read distance directly across on the distance axis.

3,000 km

9.4. At this point, from the information in Figure 9.6A, how specific can you be as concerns the location of that earthquake?

Answer: The earthquake is somewhere on the circle around Seattle

9.5. At this point, from the information in Figure 9.6B, how specific can you now be as concerns the location of that earthquake?

The earthquake is located at one of the two points where the two circles intersect.

9.6. At this point, from the information in Figure 9.6C, how specific can you now be as concerns the location of that earthquake?

The earthquake is located at the point in Montana where the three circle intersect

9.10. Using the nomogram, determine the Richter magnitude for the three earthquakes listed (see, p. 169 in the lab book).

|S arrival minus p arrival |Amplitude