Question

If the ratio of distance from the epicenter to S-P lag time is 10 to 1, what would the distance be if the S-P lag time is 23.2 minutes?

Answer 1

Subtract P-wave travel time (“tp”) from S-wave travel time (“ts”) to get S-P lag time (“ts - tp”). ts = D /vs. tp = D /vp. How far was the earthquake from my seismograph?