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Explain how scientists find the epicenter of an earthquake.
First they record the arrival times of the seismic waves.
Then they subtract the p-wave arrival time from the s-wave arrival time. This is called the S-P interval.
The S-P interval tells scientists how far away the epicenter is.
Lastly, scientists need the S-P interval from 2 other seismograph stations. Where all three of the "circles" meet is where the epicenter it.