GEOLOGY

Detailed explanation-1: -P waves travel fastest and are the first to arrive from the earthquake. In S or shear waves, rock oscillates perpendicular to the direction of wave propagation. In rock, S waves generally travel about 60% the speed of P waves, and the S wave always arrives after the P wave.

Detailed explanation-2: -Because P waves are the fastest seismic waves, they will usually be the first ones that your seismograph records. The next set of seismic waves on your seismogram will be the S waves. These are usually bigger than the P waves.

Detailed explanation-3: -P waves are recorded earlier than S waves, because they travel at a higher velocity. SF Table 7.1 shows that P waves have a higher velocity than S waves when traveling through several mineral types. The speed at which seismic waves travel depends on the properties of the material that they are passing through.

Detailed explanation-4: -P waves, or Primary waves, are the first waves to arrive at a seismograph. P waves are the fastest seismic waves and can move through solid, liquid, or gas. They leave behind a trail of compressions and rarefactions on the medium they move through. P waves are also called pressure waves for this reason.

Detailed explanation-5: -1897 – P-waves and S-waves Richard Oldham realised that there were at least two types of seismic waves that travelled at different speeds. We know these now as P-waves and S-waves. Seismic waves are waves that travel through or over Earth.