How is an Earthquake's Magnitude and Intensity Different (yet related)?

In this activity, students explore the relationship between an earthquake's magnitude and intensity. Students calculate the energy released during a weight drop (magnitude) and use an accelerometer (iPhone, QCN, or other) to investigate what happens to this energy as the source is moved further and further from the sensor (intensity). Students next examine USGS ShakeMaps to explore other factors besides and event size and the distance form the source to the receiver that can effect the intensity (e.g. geologic structures etc).


Students will be able to:

  • Students will be able to explain the information expressed in a three-component seismogram... particularly directions of motion, peak absolute amplitude and accelerations.
  • Students will be able to explain how the magnitude of an earthquake, like their weight drop, is tied to the physical properties of the fault, and b) that 
  • Students will be able to explain several factors that contribute to the intensity of shaking at a particular location

Total Time: 1h
Level: Novice

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