Understanding Earthquakes: Comparing seismograms
Summary
Learners compare multiple seismograms to gain a better understanding of how different locations respond differently to earthquake waves, and how these variations can provide information about the structure of the Earth. A set of seismograms from two Mw7.1 earthquakes near Anchorage, AK, are provided as an initial comparison option. Additional seismograms can be pre-selected and provided in hard-copy to constrain the scope of the lesson, or learners can access an online data portal to do more self-directed investigations. Educators can provide seismograms from any source, for example the Raspberry Shake ShakeNet data portal. (Opens in new window)
Context
Audience
Skills and concepts that students must have mastered
Learners should be familiar with plate tectonics and seismic P and S waves. Activities that will help learners with the background knowledge for this one are Human Wave: Modeling P and S Waves and Seismic Slinky. If learners do not already know how to interpret an earthquake seismogram, precede this activity with Reading an Earthquake Seismogram.
How the activity is situated in the course
This activity can be used early on in an earthquake unit to engage learners, or further along in an earthquake unit to prepare learners for a deeper dive in seismology.
Goals
Content/concepts goals for this activity
Learners will:
- Identify P-waves and S-waves on seismograms
- Compare P-wave and S-wave arrival times to rank the distances from the earthquake epicenter to the seismometers
- Compare amplitudes of seismic waves to evaluate the differences in shaking intensity experienced by seismometers
Higher order thinking skills goals for this activity
- Interpret graphical data
Other skills goals for this activity
- Access data in online data portals
Description and Teaching Materials
Activity
See attached file for instructor notes, NGSS alignment, and links to supporting resources.
Understanding Earthquakes - Comparing Seismograms Activity.pdf (Acrobat (PDF) 5.2MB Oct3 23)
Supporting Audiovisual
Teaching Notes and Tips
Instructors can provide seismograms from any source, for example the ShakeNet data portal. See also the Instructor Guide: Getting Started with the ShakeNet Data Portal. (Both open in new windows)
Assessment
Evaluate learners' ability to make comparisons between seismograms, and their ability to apply logical reasoning to develop explanations for the differences in amplitude, or arrival times of the waves.
References and Resources
- Learn more about Raspberry Shake (Opens in new window)
- United States Geological Survey Event Pages (Open in new window)
- IRIS Resources for viewing seismograms (Opens in new window) - links to more options for viewing seismograms from different seismic stations and earthquake events
- Figures and seismograms were provided by the Alaska Earthquake Center.
- This activity is part of ANGLE Curricular Pathway 1: Instrumentation.
- Contact ANGLE with questions or comments.