S waves oscillate the ground perpendicular to the direction of wave travel. They travel about 1.7 times slower than P waves. Because liquids will not sustain shear stresses, S waves will not travel through liquids like water, molten rock, or the Earth's outer core. (See seismic waves and Figure 2.)

Transverse waves of an earthquake that cause Earth's material to vibrate perpendicular to the direction of the waves' travel. Also called secondary or shear waves.

A seismic body wave that has motion perpendicular to the direction of travel (i.e. like light waves). They cannot travel through liquids and are slower than P Waves