28.2. Earthquake Magnitude

Try these first

1. 1.

   What does the Richter scale measure?

   Hint

   Recall what aspect of earthquakes the Richter scale focuses on.

2. 2.

   What is the formula for calculating the Moment Magnitude?

   Hint

   Think about how seismic moment relates to the magnitude formula.

3. 3.

   What is the primary function of the Richter scale?

   • Measure earthquake duration
   • Measure seismic wave amplitude
   • Measure damage level

   Hint

   Remember the specifics of what the Richter scale targets.

4. 4.

   True or False: The Moment Magnitude Scale is the most widely used scale for all sizes of earthquakes.

   • True
   • False

   Hint

   Think about the effectiveness of scale across different magnitudes.

5. 5.

   Calculate the energy released in joules for a magnitude 6 earthquake using the formula log E = 1.5M + 4.8.

   Hint

   Use logarithmic properties to find the energy extrapolated from the magnitude.

6. 6.

   Suppose an earthquake measures 7.5 on the Moment Magnitude Scale. Discuss the potential structural impacts compared to a 5.5 magnitude quake.

   Hint

   Reflect on the energy release and effects of increased magnitude on buildings.