The Bulletin

9th Graders Study Seismology and Earth Sciences

Monday, April 2012

On March 19th, as a part of their science curriculum, the 9th grade visited the Department of Earth and Planetary Sciences at Northwestern University where they met graduate students, Department Professor Suzan van der Lee and CWS parent Alison Witt-Janssen, who is the department's Program Assistant.

The students learned about three types of seismic waves, their characteristics, and how to recognize them as they appear on a seismometer. They practiced taking data from three seismometer stations in different locations (as determined by their latitude and longitude) learned about a specific earthquake and examined how to determine from this data the epicenter of the earthquake.

Using the human body to demonstrate the difference between P-waves and S-waves, they also learned how the various wave types have very different destructive effects on buildings and other structures. The students simulated earthquakes by jumping in the stairwells. They were then able to view Northwestern’s Locy Hall seismometer close up and see how the effects of students jumping up and down at various locations in the three-story building were recorded instantly by the seismometer in the basement. Two days later the students were sent images taken from that very seismometer of a 7.4 magnitude earthquake in Oaxaca, Mexico that happened the day after their visit!