Please set up your notebook.  Title the next page and update your TOC.

To define:

• focus
• epicenter
• p-wave
• s-wave
• triangulation

Questions to answer while doing the lab.  Yes, please copy the questions OR write your answers in such a way that the question was obvious.  (Do not use the "new version" offered to you.)

1. How many earthquakes are there each year that can be recorded by modern instruments? __________________
2. What is the instrument called that records the seismic waves produced by earthquakes? _________________________
3. P waves can travel through ______________________________, but S-waves can only travel through ___________________.
4. The seismograph records the energy and scientists can read the results on a ________________, the written record of the earth’s shaking.
5. How many seismographic stations are needed to determine the location of an epicenter using triangulation? ________________

Ok, now you are given the choice of selecting your earthquake region. Please do not select Japan as it has had errors in the past. 

Which location did you choose? _________________________

6. On the seismograms given, what is the increment used on the axis that shows seconds? ________________

On each of the three seismograms you are asked to estimate the S-P interval, or how many seconds passed by after the P-wave arrived before the S-wave showed up. Note: The P-wave is first. It will start the pen on the seismograph. The energy of the P-wave will slowly decrease and the pen on the seismograph will jump dramatically when the S-wave arrives. 

Your job is to see how many seconds it took for the S-wave to get there AFTER the P-wave showed up. The P-wave begins at zero. The S-wave should be measured by finding its beginning and then reading the number of seconds on the x-axis, or seconds axis, just below it. BE AS EXACT AS POSSIBLE!

Have you entered all three readings? Click "Convert to S-P Interval."

7. Which of the 3 curves/lines shown on the S-P Interval graph will you use for the rest of this exercise? ________________
8. How many circles appeared on the next page after you measured the S-P interval? ______________
9. Each circle was drawn with a compass. The point of the compass was put in the city where the seismograph station was located. The compass was opened to a distance that matched the distances given on the S-P interval graph. The epicenter SHOULD be where these three circles _______________________. (If you have to re-measure and the pictures don’t show up, you can use the back key to get back to the original seismograms.)
10. What is the city you triangulated (the epicenter)? ________________
11. What are three ways given to evaluate the relative strength of an earthquake?

a.

b.

c.

12. The _________________ of an earthquake is an estimate of the total amount of energy released during fault rupture.
13. What is the interval on the y-axis for amplitude (height of the tallest wave)? ____________________
14. What is the graph that is used to simplify the relationship between amplitude and S-P interval to find magnitude? ______________ Study this tool well. The intervals on each line are not equal and should not be cause for confusion. Just roll with it!

• After trying to PRECISELY determine the magnitude, you will be taken to a screen that says "Richter Magnitude Confirmation."
• Please type your name, your PERIOD where it says "Institution," and city, state can be left blank or type RMSA.
• Email a screen shot of the page that shows the DATA TABLE filled in with your results!  A green certificate page may be offered to you, but I can't use that page for your grade.  I must have the completed data table.   NOTE:  Some of the "actuals" are not correct.  I have done all four earthquakes, and I have the TRUE 'actuals" written down.  Do NOT worry if your answers do not match theirs - you will be graded on how closely your answers match mine.