Answers

2016-06-22T19:54:56+08:00
The P-waves and S-waves

P-waves or Primary wave is the wave that comes first when an earthquake occur.

S-waves or secondary waves are the waves that came after the P-waves and has an interval of 8 seconds between the two.

The two are extremely useful to the study of seismologist as it helps them locate epicenters and such.
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