seismometers

On the use of seismic Rayleigh waves in security systems

There are four types of seismic waves: primary waves , secondary waves , wave Rayleigh and Love waves. The first two types are called depth waves, because these waves penetrate into the depths of the earth. Rayleigh waves and Love waves called surface waves. They can to propagate on the surface. Given the characteristics of propagation of these waves can be concluded that even at low energies excitation source, Rayleigh waves can propagate at a much greater distance than depth waves, so it would be advisable to use them in security systems.