Earth Science                                                                            Direction Sheet

Computer Lab: Earthquakes and Volcanoes                                       WRITE ON YOUR PAPER.

  1. Start from Dr. Weekes' Site:
  2. Click on Links to Other Sites
  3. Click on Volcano and Earthquake links for Class
  1. Virtual Earthquake.

This takes a little reading but you find out how to locate earthquakes and how to determine how strong they are.
Answer the numbered questions on your paper.
1. __________________________ Earthquake Location you chose. Submit Choice

Read about S and P wave arrival time. Then View Seismograms

Remember the arrival of the P wave is at the 0 time. The first bump of the arrival of the S wave is what you look for. Read directly the difference of the arrival times at the bottom of the seismogram. Each line is 2 seconds.

then Convert S - P Interval

Find your interval times and then as accurately as you can use the graph to determine the distance to the epicenter.

then Find Epicenter

How well did you do? If you did not get very close try remeasuring and do it again.

Either Remeasure S - P Interval or View True Epicenter.
When you are happy with your data do the View True Epicenter.

2. How well did you do? Make a table like below.


Your Data

Actual Data

Recording Station

S - P Interval

Epicenteral Distance

S - P Interval

Epicenteral Distance

















Go on to Compute Richter Magnitude.

Read the explanation and pay close attention to the example graph.

Then Go To Next Page. Again read then Go To Next Page.

then Submit to Nomogram

3. What was your estimate of the magnitude of earthquake?____

then Confirm Magnitude

4. What was the actual magnitude? ____

You can fill out the certificate information and print your certificate if you passed.
Show your teacher your certificate for credit.

  1. Recent Earthquakes

Go to:

National Earthquake Information Center

Scroll down to the 3 part map of the world.

  1. What do the different colors represent for the earthquakes plotted on the map?
  2. Do the locations of the earthquakes mostly match up with the plate boundaries?
  3. Describe 3 of the most recent earthquakes. Get information by clicking on them on the map.
    Make a table like below.


Time UTC



Depth (km)

Magnitude (Mb)
























For one of the earthquakes, click on Historical Seismicity.

  1. Have there been many earthquakes here before?
  2. Are there any patterns to the depths?
  3. Look at the Historical Seismicity for an earthquake in the Western Pacific Ocean.

a. Describe the pattern you see.

b. Were any of the earthquakes deep?

c. What would explain this?

  1. Volcanoes- Use the links to find the information.

1. What are the different types of volcanoes?




maybe d.

2. Look for the examples of recent volcanic activity.
Use the Worldwide Volcanic Reference Map to link to descriptions of active volcanoes.
Make a table like below.

Name of Volcano

Location of Volcano

Type of Eruption or Description











3. Explore some of the volcano links. Tell what you found or did.
Make a table with these headings.

Link Name or Location

What was cool or what did you learn?