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They usually travel slightly faster than Rayleigh waves Love waves cause horizontal shearing of the ground.People have claimed to have observed Rayleigh waves during an earthquake in open spaces, such as parking lots where the cars move up and down with the waves. Rayleigh waves, also called ground roll, travel as ripples similar to those on the surface of water.There are two basic kinds of surface waves: Although surface waves travel more slowly than S-waves, they can be much larger in amplitude and can be the most destructive type of seismic wave. They are typically generated when the source of the earthquake is close to the Earth’s surface. Surface waves are similar in nature to water waves and travel just under the Earth’s surface. S-waves cannot travel through air or water but are more destructive than P-waves because of their larger amplitudes Surface waves Again, imagine a slinky partially stretched, except this time, lift a section and then release it, a transverse wave will travel along the length of the slinky. In this case, particle motion is perpendicular to the direction of wave propagation. S-waves, also known as secondary waves, shear waves or shaking waves, are transverse waves that travel slower than P-waves. They differ from S-waves in that they propagate through a material by alternately compressing and expanding the medium, where particle motion is parallel to the direction of wave propagation – this is rather like a slinky that is partially stretched and laid flat and its coils are compressed at one end and then released. Because of their speed, they are the first waves to be recorded by a seismograph during an earthquake. When they travel through air, they take the form of sound waves – they travel at the speed of sound (330 ms -1) through air but may travel at 5000 ms -1 in granite. P-waves, also known as primary waves or pressure waves, travel at the greatest velocity through the Earth. P-waves and S-waves are sometimes collectively called body waves. There are three basic types of seismic waves – P-waves, S-waves and surface waves. This wave behaviour can also be used on a smaller scale by recording waves generated by explosions or ground vibrators in the search for oil and gas. The results can provide a snapshot of the Earth’s internal structure and help us to locate and understand fault planes and the stresses and strains acting on them. Because of the different behaviour of waves in different materials, seismologists can deduce the type of material the waves are travelling through.

As the waves travel through different densities and stiffness, the waves can be refracted and reflected. Seismologists use seismographs to record the amount of time it takes seismic waves to travel through different layers of the Earth.