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: -On a seismogram from an earthquake, the P-wave is the first signal to arrive, followed by the slower S-wave, then the surface waves. The arrival times of the P-and S-waves at different seismographs are used to determine the location of the earthquake.

Detailed explanation-3: -If a seismogram records P-waves and surface waves but not S-waves, the seismograph was on the other side of the Earth from the earthquake because those waves cannot travel through the liquid core of the earth.

Detailed explanation-4: -Earthquake detection. A seismogram is a record of the ground motions caused by seismic waves from an earthquake. A seismograph or seismometer is the measuring instrument that creates the seismogram.

Detailed explanation-5: -Body waves travel through the body of a planet. Surface waves travel along the surface. There are two types of body waves: P-waves travel fastest and through solids, liquids, and gases; S-waves only travel through solids. Surface waves are the slowest, but they do the most damage in an earthquake.