Name:
SW US Seismogram
The activity below involves studying three seismograms from an earthquake. You will use the same tools and methods that a seismologist uses to find the epicenter of the earthquake.
- Study the three seismograms on the back side of this paper.
- For each seismogram, determine the S-P interval and the amplitude.
- Use the S-P graph and the S-P intervals to find the distance from the epicenter to each seismic station (epicenter distance).
- Determine the epicenter of the earthquake by using a compass to draw a circle around each seismic station. The radius of each circle should be equal to the epicenter distance determined with the S-P graph. The epicenter is the point where all three circles intersect.
Seismogram Data Table
| Location | Amplitude (mm) | S-P Interval (seconds) | Distance (km) |
| Reno, NV | |||
| Salt Lake City, UT | |||
| Flagstaff, AZ |
Location Map
Seismograms

