Pasta Quake & Earthquake Magnitude

Paul Doherty (Exploratorium Teacher Institute) and Roger Groom (Mt Tabor Middle School) with improvements by ShakeAlert


Summary

This short activity provides an intuitive introduction to earthquake magnitude using an everyday item--spaghetti. Learners are introduced to the earthquake magnitude scale by breaking different amounts of uncooked noodles. Visual scale of the pasta emphasizes the relative differences between magnitudes steps. For older students, the demonstration helps students understand why seismologists use the nonlinear logarithmic scale to best graph the huge range of quantities.

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Context

Audience

This activity could be done with introductory geoscience learners from late elementary through secondary or even early college. It can also work for informal education or public outreach venues as a demonstration or interactive.

Skills and concepts that students must have mastered

Learners should already know what earthquakes are.

How the activity is situated in the course

Use this activity mid-way through a Plate Tectonics Unit, to introduce earthquake magnitude, and prepare learners to understand the difference between magnitude and intensity.

Goals

Content/concepts goals for this activity

Learners will be able to

  • Define the difference between Richter Magnitude, Moment Magnitude, and Intensity
  • Explain the energy difference between different Moment Magnitude steps.

Higher order thinking skills goals for this activity

  • Modeling with mathematics, reasoning quantitatively

Other skills goals for this activity

  • Older students will be able to learn a practical application of logarithmic scales.

Description and Teaching Materials

The severity of an earthquake can be described using two different scales: magnitude and intensity. The magnitude is a measure of the amount of energy released in the earthquake, whereas intensity is a measure of the impact of the earthquake, in terms of shaking and destruction caused. This activity focuses on the magnitude scale, providing a visual model that illustrates that the scales used to measure earthquake magnitude are non-linear. Comparing the number of deaths that occurred in several large destructive earthquakes that have occurred worldwide since 1960 allows learners to begin to ponder what other factors besides earthquake magnitude contribute to the intensity of earthquakes and the damage caused.

See files for educator notes, NGSS alignment, links to supporting resources, student exercise, and answer key.


Two animations which strongly support activity concepts:

Teaching Notes and Tips

  • See also the educator notes in the document above.
  • Materials needed for a full demonstration of Magnitudes 5 to 9:
  • Single strand of spaghetti for each learner plus some extras (Mag 5)
  • One or more bundles of 32 strands (Mag 6). If you are using this just as a visual aid, one rubberbanded bundle is enough. Have additional bundles if you want learners to have the chance to "make" a Mag 6 earthquake themselves. (note: pasta fragments will scatter everywhere so it may help to break it over a tray or tub)
  • One bundle of ~1024 strands (Mag 7). (note: this is about 2 pounds for standard spaghetti)
  • Circle ~15 inches across (Mag 8). This represents the approximate cross-sectional area of 32x1024=32,768 spaghetti strands. Tarp material or plastic sheeting works well.
  • Circle ~7 feet across (Mag 9). This is the approximate cross-sectional area of 32x32,768=1,048,576 spaghetti strands. Tarp material, plastic sheeting, or perhaps a round table cloth can work well.
  • A small extension can be having students work with the IRIS Earthquake Simulator. It lets them modify earthquake parameters such as area and slip distance in order to see how big an earthquake is created.

Assessment

The student worksheet, if used, serves as the summative assessment for the activity. However, some instructors may choose to just use this activity as a demonstration instead of do a formal assessment. If that is the case or if one is working with an informal audience, learner understanding can be gathered from questions to and discussions with small groups or the whole group.

References and Resources