surface waves
Surface waves travel along the ground outward from an earthquakes epicenter. Surface waves are the slowest of all seismic waves. They travel at 2.5 km 1.5 miles per second. There are two types of surface waves. Love waves move side-to-side, much like a snake. Rayleigh waves produce a rolling motion as they move up and backwards Figure above . Surface waves cause objects to fall and rise, while they are also swaying back and forth. These motions cause damage to rigid structures during an earthquake.