U.S. Geological Survey, Adapted with permission.
Have you ever felt an earthquake? What was it like? Where were you? What did you do? More than 143 million people are exposed to potentially damaging shaking in the United States.
When an earthquake happens, seismic waves travel outward in all directions. Primary (P) waves travel faster than secondary (S) waves, which do most damage. But electronic information can be sent faster than P and S waves. The ShakeAlert Earthquake Early Warning Systemcan detect an earthquake quickly and send an alert before strong shaking arrives. A few seconds of warning does not sound long, but it is enough time to do something to protect yourself, such as Drop! Cover! and Hold On!
The U.S. Geological Survey (USGS) along with universities and state agencies in Washington, Oregon, Nevada, and California are developing the ShakeAlert Earthquake Early Warning (EEW) System for the West Coast.Several countries including Japan, Mexico, Taiwan, and China already use EEW systems.
A ShakeAlert can also be sent to a hospital, a light rail system, a fire station, a water provider utility, or a school to trigger automated actions such as starting emergency generators, slowing down trains, opening fire house doors, closing water system valves, or playing a pre-recorded message on a loud speaker.
- Rare earth magnets, preferably elongated design
- PVC pipe, about 1” in diameter, cut into 1.5” long pieces
- Spool of thin copper wire, with thin, insulating coating
- Fine sandpaper
- 2 gator clips
- Thick cardboard
- Rubber bands
- Tightly coil copper wire around PCV pipe, leaving about ¼-inch at both ends and about 10 inches of wire extending out from each end. Tape the wire in place and use sandpaper to remove coating from the wire.
- Connect a gator clip to each end of the wire, and connect each to the positive and negative connections on the ammeter.
- Move magnets back and forth inside the solenoid. By doing this, the changing magnetic field creates a changing electric field, producing an electric current. What happens to the needle in the ammeter?This is called “induction,” a small, simple version of how many power plants work.
- Use other materials to set up a system—a seismometer—that will allow the magnets to move back and forth through PVC pipe. Tape, rubber bands, and thick cardboard are a few examples of materials.
- Develop, test, and modify your designs to see what works best. Share designs with the class.
ShakeAlert STEM Classroom Discussion
How would various situations be made more safe if people and automatic systems were alerted that they were about to experience earthquake shaking? A surgeon performing an operation? A chemistry teacher and students in a lab? An amusement park with lots of fast rides? What can you do to keep yourself safe during an earthquake?
Full Classroom Activity and More - STEM Connections to the US Earthquake Early Warning System:
NGSS 3-D Learning
- Science and Engineering Practices–Obtaining, Evaluating, and Communicating Information
- Disciplinary Core Ideas– Earth and Human Activity
- Crosscutting Concepts–Cause and Effect