Earthquakes produce several types of shock waves. The most well-known are the P-waves (P for primary or pressure) and the S-waves (S for secondary or shear). In the earth's crust, the P-waves travel at around 6.5 km/s while the S-waves move at about 3.5 km/s. The actual speeds vary depending on the type of material they are going through. The time delay between the arrival of these two waves at a seismic recording station tells geologists how far away the earthquake occurred.
If the time delay is 33 seconds, how far from the seismic station did the earthquake occur?
10 points to whoever can answer AND explain most clearly. I want to know how to do it, not just the answer.
If the time delay is 33 seconds, how far from the seismic station did the earthquake occur?
10 points to whoever can answer AND explain most clearly. I want to know how to do it, not just the answer.
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You have an unknown distance that equals both 6.5 m/s • t and 3.5 m/s • (t + 33).
6.5t = 3.5(t + 33)
6.5t = 3.5t + 115.5
3t = 115.5
t = 38.5 second
The P wave had a travel time of 38.5 seconds and the S wave had a travel time of 71.5 seconds.
6.5 km/s • 38.5 s = 250.25 km
3.5 km/s • 71.5 s = 250.25 km
That checks.
6.5t = 3.5(t + 33)
6.5t = 3.5t + 115.5
3t = 115.5
t = 38.5 second
The P wave had a travel time of 38.5 seconds and the S wave had a travel time of 71.5 seconds.
6.5 km/s • 38.5 s = 250.25 km
3.5 km/s • 71.5 s = 250.25 km
That checks.
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6.5 km/sec x 33 seconds = 214.5 kilometers.
Hoever, you seem to be totally ignorant that you need seismic data from at LEAST three locations to figure out where the holocenter and epicenter of an earthquake are. No, I'm not going to expalin that. I answered the question.
Hoever, you seem to be totally ignorant that you need seismic data from at LEAST three locations to figure out where the holocenter and epicenter of an earthquake are. No, I'm not going to expalin that. I answered the question.