Editing Surface wave (section)

==Mechanical waves==
{{further|Gravity wave}}

In [[seismology]], several types of surface waves are encountered. Surface waves, in this mechanical sense, are commonly known as either ''[[Love wave]]s'' (L waves) or ''[[Rayleigh wave]]s''. A [[seismic wave]] is a wave that ''travels through the Earth, often as the result of an earthquake or explosion.'' Love waves have [[transversal wave|transverse]] motion (movement is perpendicular to the direction of travel, like light waves), whereas Rayleigh waves have both [[longitudinal wave|longitudinal]] (movement parallel to the direction of travel, like sound waves) and transverse motion. Seismic waves are studied by seismologists and measured by a seismograph or seismometer. Surface waves span a wide frequency range, and the period of waves that are most damaging is usually 10 seconds or longer. Surface waves can travel around the globe many times from the largest earthquakes. Surface waves are caused when P waves and S waves come to the surface.

<!-- The term "surface wave" can describe waves over an ocean, even when they are approximated by [[Airy function]]s and are more properly called [[creeping wave]]s. << Neither of the linked articles mentions water waves or (mechanical) surface waves. Is this really a helpful reference? -->Examples are the [[wave]]s at the surface of [[water]] and [[air]] ([[ocean surface wave]]s).  Another example is [[internal wave]]s, which can be transmitted along the interface of two water masses of different densities.

In theory of [[Hearing|hearing physiology]], the traveling wave (TW) of [[Von Bekesy]], resulted from an acoustic surface wave of the [[basilar membrane]] into the [[cochlear duct]]. His theory purported to explain every feature of the auditory sensation owing to these passive mechanical phenomena. Jozef Zwislocki, and later [[David Kemp (physicist)|David Kemp]], showed that that is unrealistic and that active feedback is necessary.