Discussion Questions: Earthquakes: The Seismograph

• Discuss the differences between P and S waves. Why do you think these different kinds of waves have different effects? Describe the effects of each.
• Replay the section on the Lisbon earthquake. Describe when the P waves hit and what happened. Do the same for S waves.
• Discuss how the Lisbon earthquake informed our understanding of earthquakes.
• How does a seismograph record an earthquake's waves?
• On the Richter scale, how much stronger is a 7 than a 6? How much stronger is an 8 than a 6?