Name: _____________________ Period: _________ Date: ___________
Address: http://www.sciencecourseware.org/VirtualEarthquake
This activity simulates the investigation of an earthquake. You will be responsible for evaluating seismograms and assigning a Richter value to a virtual earthquake.
Procedure:
1. Go to the site listed above.
2. Click Execute Virtual Earthquake on the bottom of the page.
3. Read the material presented.
4. In kilometers per second, how fast do P-waves travel? _______________
5. In kilometers per second, how fast do S-waves travel? _______________
6. Why aren’t these speeds exact? What are two factors that effect the speed of waves?
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7. Choose either Southern CA, Japan, or Mexico sites for your earthquake.
8. Click Submit Choice.
9. Read the "Determining the Earthquake Epicenter" page with map.
10. Finish this sentence : Measure the S-P interval to the nearest _________.
11. Click View Seismograms.
12. Read the directions and evaluate seismograms. Type in intervals for each of the three graphs.
13. Click Convert S-P Interval.

14. Read "Determining the Earthquake Distance" page. Use the chart to determine the Distance from S-P Intervals. Type in the values for each recording location.
15. Click Find Epicenter.
16. Read "Triangulation of the Epicenter" page. Have a teacher look at it & initial here: ___________
17. Click Compute Richter Magnitude.
18. Read "Richter Magnitude" page.
19. What does the Richter Scale measure? __________________________
20. How large does an earthquake have to be on the Richter Scale to be felt by humans?
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21. You’ve already measured the S-P interval. What else do you need to measure to calculate the Richter Magnitude?
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22. Click Go To Next Page.
23. Read "Richter Nomogram".
24. Click Go To Next Page.
25. Compute magnitude for each seismogram. Enter values for each graph.
26. Click Submit To Nomogram.
27. Enter your estimate for the magnitude. (Use the middle scale, and look where each of the three lines intersects there.) Click Confirm Magnitude.
28. Read "Richter Magnitude Confirmation" page. Have a teacher look at it & initial here: ___________