28.10. Attenuation Relationships (Ground Motion Prediction Equations)

Try these first

1. 1.

   What is attenuation?

   Hint

   Think about how distance affects shaking intensity.

2. 2.

   What does PGA stand for?

   Hint

   Focus on the 'P' for peak.

3. 3.

   What does attenuation refer to in the context of earthquakes?

   • Increase in ground motion
   • Decrease in ground motion
   • No effect on ground motion

   Hint

   Think about what happens to vibrations as you move away.

4. 4.

   True or False: The Peak Ground Acceleration (PGA) can be directly measured at the source of an earthquake.

   • True
   • False

   Hint

   Where does the measurement need to occur?

5. 5.

   Given a magnitude 7.0 earthquake occurring at a depth of 10 km, use an attenuation model to estimate the PGA at a location 20 km away. Discuss your approach and calculations.

   Hint

   Identify the constants for your specific model.

6. 6.

   Analyze how geological variances might lead to the cropping of peaks in different seismic regions when predicting PGA. Provide examples.

   Hint

   Consider how waves might change in shape and intensity.