As an experienced "Earth surfer" I can say that the S and P waves (Primary and Secondary) are distinct and easy to tell apart. "P" waves are the rumble and the ones that give you that kind of queasy feeling underfoot and the sharp jolts and "bangs" are the "S" waves.

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In your rush to call everyone "entrenched" or closed-minded or "limited" you fail to note that the "limit" here has a very natural boundary: that point at which the evidence stops. - JayUtah

Science fiction was never meant to be an educational tool. - Editor Amazing Tales