Quantitative Skills > Teaching Resources > Activities > Determining Earthquake Probability and Recurrence

Determining Earthquake Probability and Recurrence from Past Seismic Events

Eric M. Baer (derived from material originally published in Whittington and Baer, 2005)

Geology Program, Highline Community College
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In this homework and in-class exercise, students use real historical data from small earthquakes to estimate the recurrence interval of rare large earthquakes. This activity is designed for the Pacific Northwest, but could easily be altered for any other area. The activity uses the Gutenburg-Richter relationship, which states that the number of earthquakes of magnitude M is proportional to 10-bM. The activity also attempts to get students to examine the limitations of sampling, deal with outliers in a thoughtful way, compare the results of this technique with results of another technique (paleoseismology), and finally to look at the societal impacts of their results.

Learning Goals

Northridge Earthquake image
Damage done to a parking ramp by the Northridge Earthquake. Details
At the end of this exercise, students should be able to:

Context for Use

I use this in an introductory geohazards course, but it could be used in any course with earthquakes as a focus. I find students need substantial assistance from the instructor, so I would recommend classes smaller than 30. If the students complete the homework assignment, the part in-class takes one to one and a half hours. I like this assignment because it teaches many basic data analysis techniques, uses real data, and comes to real conclusions.

Teaching Notes and Tips

Teaching Materials

Here is the exercise, in word format. Forecasting Future Earthquakes (Microsoft Word 83kB Feb20 05)
You will need log paper to graph the magnitude and period on. Here (Excel 12kB Feb20 05) is an excel graph done for this.


I grade the submitted homework and lab.

References and Resources

Whittington, C. and E.M. Baer, 2005. "Workbook in Geologic Catastrophes" Kendall/Hunt Publishing, Dubuque IA 154 pp.

Controlled Vocabulary Terms

Subject: Geoscience:Geology:Structural Geology:Geophysics and Structural Geology, Environmental Science:Natural Hazards:Earthquakes, Geoscience:Geology:Geophysics
Resource Type: Activities:Classroom Activity, Lab Activity
Special Interest: Geo2YC- OLD DO NOT USE, Quantitative, Hazards, 2YC:Geo2YC
Grade Level: College Lower (13-14):Introductory Level
Quantitative Skills: Arithmetic/Computation, Probability and Statistics, Graphs, Logarithms/Exponential Functions:Logarithms, Logarithms/Exponential Functions, :Exponential Growth and Decay, Probability and Statistics:Probability, Describing Data Distribution, Data Trends:Curve Fitting/Regression, Probability and Statistics:Data Trends
Ready for Use: Ready to Use
Use: Enabling Student Investigation:Collect and interpret data, Illustrating concepts and ideas, Enabling Student Investigation:Analyze published data
Data Derived: Data Derived
Earth System Topics: Solid Earth:Deformation, Earthquakes, Human Dimensions:Natural Hazards
Quantitative Skills Activity Type: Classroom Activity, Lab Activity
Topics: Human Dimensions/Resources, Solid Earth:Structural Geology:Geophysics and Structural Geology/Earthquakes/Seismic Reflection Profiling, Solid Earth

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