Name ________________________________________________ Chapter 12 Investigation Worksheet To complete this worksheet, see the instructions in the textbook (Chapter 12 Investigation). Table 1. Using Seismograms to Locate an Earthquake Observations: Using the Chapter 12 Investigation in your textbook, look at the area and read the descriptions associated with each location. Think about what each statement implies about possible earthquake hazards for that location. The blue-gray triangles represent the location of seismic stations in the area. Inspect the three seismograms below to determine where the earthquake probably occurred. You can get an idea from comparing the time intervals between the arrivals of P-waves and S-Waves for each station. Answer the question below the graphs. Three Seismograms Graph to Determine Distance from Epicenter From the general location of the earthquake, which geologic feature is likely to have caused the earthquake? ___________ Your instructor may have you use the graph of distance versus P-S time interval to more precisely locate the epicenter of the earthquake. Chapter 12 Investigation Worksheet; page 2 Table 2. Impact of an Earthquake for Each Town For each of the towns located in this area, what do the topographic and geologic features of the landscape infer about what types of hazards the recent earthquake poses for each town. Decide which three towns are the least safe and which two are the safest, and circle your choice in the table below. There is not necessarily one right answer, so explain and justify your logic in the space provided. Name of Town Sandpoint Hillside Cascade Village Mesaview Cliffside Riverton White Sands Possible Earthquake Hazards Least safe/Safest Least Safe / Safest / Neither Least Safe / Safest / Neither Least Safe / Safest / Neither Least Safe / Safest / Neither Least Safe / Safest / Neither Least Safe / Safest / Neither Least Safe / Safest / Neither Justification Name ____________________________________________ Chapter 12 Investigation Worksheet; page 3 Table 3. Locating the Epicenter of the Earthquake (Optional) If your instructor asks you to, use the graph of distance versus P-S time interval (on Table 1) to more precisely determine the location of the epicenter of the earthquake. To determine how far the earthquake was from each seismic station, use the P-S time interval for a seismic station and read off the corresponding distance from the P-S time-interval graph. Then, approximately scale off the appropriate distance from the earthquake to the seismic station and sketch part of a circle with this radius around the seismic station. The triangles on the figure below represent the location of seismic stations.