Method
- Invite schools to participate as "monitoring sites"
- Create the synthetic seismograms (an advanced class can do this)
Note - this is not a synthetic seismogram in the full-blown computational
sense.
- Decide the location and magnitude of the earthquake based on fault maps.
- Determine the distance from the earthquake to each school
- Create each seismogram so that s-p time correlates with distance
- Create each seismogram so that aplitude correlates with distance and
magnitude
- Schools obtain individual seismograms as ascii time series (amplitude
vs time)
- Students use a spreadsheet, matlab, a graphing package to graph the
data to determine the arrival time of the p wave and the arrival time of the
S wave.
- Using charts and graphs readily available from textbooks or web
sites, students can use the s-p difference to estimate the distance to the
quake and a combination of the amplitude and s-p difference to determine
the magnitude of the quake.
- Schools send back their best estimate of distance and magnitude.
- Share all information with participating schools.
- After most schools have posted results, students use the estimates
of distance to locate the epicenter by "triangulation".
- Use distance from each "monitoring site" to construct circles
around the site.
- Determine the most probable earthquake site from the intersection
of circles. This can be done using a map and compass or computationally.
- Each school sends its best estimate of location and magnitude.
Resources
Getting Real Seismograms
- Redwood City Public
Seismic Network uses a special data format but includes information
on obtaining the necessary software. It also has information on building
your own seismograph.
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