Earthquakes Living Lab: Finding Epicenters & Measuring Magnitudes
A process called triangulation uses seismic data from three locations to identify the epicenter of an earthquake.Copyright USGS http://earthquake.usgs.gov/learn/kids/eqscience.php
Students learn how engineers characterize earthquakes through seismic data. Then, acting as engineers, they use real-world seismograph data and a tutorial/simulation accessed through the Earthquakes Living Lab to locate earthquake epicenters via triangulation and determine earthquake magnitudes. Student pairs examine seismic waves, S waves and P waves recorded on seismograms, measuring the key S-P interval. Students then determine the maximum S wave amplitudes in order to determine earthquake magnitude, a measure of the amount of energy released. Students consider how engineers might use and implement seismic data in their design work. A worksheet serves as a student guide for the activity.
Every year, earthquakes cause death and destruction worldwide. These natural disasters may be mitigated, however, by insightful and creative engineering. Engineers first determine where earthquakes are likely to occur, and how severe they are likely to be. They use three seismographs in a process called triangulation to determine earthquake epicenters. Using historical seismographs, engineers forecast the strength or magnitude of earthquakes and make predictions and determine building codes and safety protocols.
Scientists and engineers around the globe gather data through observation and experimentation and use it to describe and understand how the world works. The Earthquakes Living Lab gives students the chance to track earthquakes across the planet and examine where, why and how they are occurring. Using the real-world data in the living lab enables students and teachers to practice analyzing data to solve problems and answer questions, in much the same way that scientists and engineers do every day.
After this activity, students should be able to:
- Use the process of triangulation to locate an earthquake's epicenter.
- Explain the difference between S and P waves, and how their time interval is used to determine the epicenter location.
- Describe the logarithmic nature of the earthquake magnitude scale.