GEOLOGY

Detailed explanation-1: -S waves shake the ground in a shearing, or crosswise, motion that is perpendicular to the direction of travel. These are the shake waves that move the ground up and down or from side to side. S waves are called secondary waves because they always arrive after P waves at seismic recording stations.

Detailed explanation-2: -Seismic waves cause intense shaking at the Earth surface that can cause buildings and roads to collapse.

Detailed explanation-3: -S-waves move side to side (or up and down). They change the rock’s shape as they travel. S-waves are about half as fast as P-waves, at about 3.5 km (2 miles) per second. S-waves can only move through solids.

Detailed explanation-4: -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-5: -P waves, or primary waves, arrive first while S waves, or secondary waves, arrive second. Both waves cause the ground to shake when an earthquake occurs. S waves cause more intense shaking than P waves and are typically much more destructive.