NAME________________________________________D_________________P_____ Earthquake Review 1. Base your answers to this question on the map below. Seismic stations are located at the four cities shown on the map. Letter X represents the epicenter of an earthquake determined from seismic waves recorded at all four cities. Which map correctly shows how the location of the epicenter was determined? NAME________________________________________D_________________P_____ Earthquake Review 2. For seismic waves that travel through the Earth, the Travel-Time curves for P and S- waves are curved (example on the right). Why do you think this is? Curves because the wave is introduced to new material/Layer causing it to change direction and speed 3. Define reflected and refracted. Reflection- seismic waves hit a material/surface and they bounce back Refraction- seismic waves hit a material and bend changes speed and direction (velocity) NAME________________________________________D_________________P_____ Earthquake Review 4. Decide on the diagrams below which one is reflected and refracted and explain how you know. Refraction – bending through layers Station 1 Station 2 Earthquake Station 4 Station 3 5. Which stations will record fewer waves than other? Explain how you know NAME________________________________________D_________________P_____ Earthquake Review Station 2 and 3 because S waves can not reach those stations because they can not travel through a liquid core. 6. What do the changing P-wave velocities mean? Velocity- speed and direction (distance/ time When a p wave changes speed and/or direction we know that it has entered a new layer of the Earth 7. Using the graphs below circle where P-wave changed velocity. Explain how you know. NAME________________________________________D_________________P_____ Earthquake Review 8. Use the graph above to find the distance for each city. City Lag Time Distance Detroit, MI 3 min Charleston, SC 7 min 20 sec Minneapolis, MN 5 min 20 sec 2000 km 6000 km 4,200 km