How do we know where the epicenter of an earthquake occurred? We use triangulation! In this activity, students will analyze seismograms and use compasses to determine the epicenter of an earthquake. There are 3 earthquakes included in your download. Prior to this lesson, students should already have a basic understanding of how a seismogram works and how to identify P and S waves. Note: Compasses are needed to complete this activity.

Included in your purchase are two versions:

Version 1: Students read a single line graph for S-P lag time, and do not have to determine the earthquake’s time of origin.

Version 2: Students read a double line graph for P and S arrival times, and have to determine the earthquake’s time of origin.

Regardless of the version, the maps and epicenters are the same. That means you can pass out version 1 to your lower level or SPED students, pass out version 2 for your higher achieving students, and they will still end up at the same answer. Great for accommodation!

(A Youtube link tutorial is also included. If you have never done triangulation before, it is helpful to watch one time before completing with students).