In this activity, students are introduced to the three-component output of an accelerometer as they enter class (or someone jumps next to it). As a whole class students explore how the device records ground motion. Students use circle maps to organize their prior knowledge of seismograms. Next, the students compare the output of the three-component accelerometer with three-component seismic data. To help students understand what the seismic data is illustrating students attempt to move the accelerometer in a way that produces an output similar to the seismogram they see. Building on this, students then apply their prior understanding of seismic waves. Specifically, students consider how the particles are moved as the wave propagates and which axis each wave type would be recorded on most strongly. The activity wraps up asking students to watch security camera footage of a quake and identify when the P, S, and Surface waves arrive based on their new understanding of seismic waves and ground motion.
Students will be able to:
- Explain the basic information expressed by a three-component seismogram.
- Identify P and S waves on a three-component seismogram.