Please help with this as I can not understand it at all. Imagine you've been shown a seismogram from an earthquake on which you can see the first arrival of P waves, followed some time later by the first arrival of S waves. You work out that the S wave arrived 5 minutes after the first P wave. Use this information to estimate the epicentral angle, explaining how you arrived at your answer
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This answer isn't really helpful. Can somebody give a general explanation as to how you can work out the epicentral angle? I've got the same question and have been provided with a graph of p wave and s wave travel time. I'm assuming you find the place on the graph where the difference between the s and p waves is 5 mins, but do you measure the epicentral angle from the p wave curve or the s wave curve?
Ignore what I just said!! The answer just popped into my head after about half an hour of staring blankly at my book. (I'm assuming this is OU S105) I think what you have to do is find the point where the S wave and P wave are 5 mins apart (you should be able to measure what 5 mins equals in mm from the y axis of the graph you've been given). Read the graph down between the two points on the S and P curves to read the epicentral angle.