What is a seismic wave?

Seismic wave is a wave produced after energy is released at the source of the earthquake. It can have a natural source or can be man made with strong expolosions. It can be P (primar) wave or S (secondary) wave. It is a form of sound wave where particles are moving and making it.

A wave pulse which would appear on a seismometer as a seismograph if there were to be a "thump" in the earth. that "thump" could be an earthquake or a very very very big explosion - a nuclear expl would do as v v v v v v big