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What Can We Learn From Seismic Waves?. D24. Seismograph stations can give us information about earthquakes. Time lag Is the time difference between the arrival of the two waves Tells how far away you are from the epicenter, NOT the direction of the earthquake.
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Seismograph stations can give us information about earthquakes. • Time lag • Is the time difference between the arrival of the two waves • Tells how far away you are from the epicenter, NOT the direction of the earthquake
P Waves show up on seismograph first, then S Waves • Near the epicenter, the time lag is short • Further away, the time lag is longer
How scientists find the epicenter of an earthquake • Draw a circle around the station. • The epicenter can be anywhere in that circle. • Contact two other seismograph stations and find the lag time noted at each station. • Lag time tells how far the epicenter is from each station. • Draw a circle around each place and the epicenter is the point where all three circles come together.