Rayleigh wave

Summary

A Rayleigh wave is an elastic wave that travels along the free surface of a solid and dies out exponentially with depth. The particles move in ellipses in the vertical plane through the direction of travel, combining a compressional and a shear part. On a homogeneous isotropic half-space it travels without dispersion at a speed a little below the S-wave speed. Lord Rayleigh predicted these waves in 1885. They carry most of the shaking of an earthquake at the surface, and they are used in surface acoustic wave devices.