Mantle Rayleigh Wave 1
Mantle Rayleigh Wave 1 : The free surface of the Earth permits the existence of two additional types of seismic waves, called surface waves. Rayleigh waves have particle motions near the ground surface that are elliptical in a vertical plane; when surficial soil or rock layers are present, or there is a gradient in elastic properties, horizontally polarized surface waves called Love waves also propagate. Rayleigh waves propagate along the Earth's surface with retrograde elliptical motion in the vertical plane of propagation. The amplitude of the particle motion tends to die out at depth. In a homogeneous medium with a Poisson's ratio of about 0.25 (commonly taken as the nominal value for rocks), Rayleigh waves will travel at a velocity of about 0.92 that of the shear velocity. Both Rayleigh and Love waves are spreading or dispersed waves that in the Earth travel with group and phase velocities that tend to be higher for low frequencies than for high frequencies. The mantle Rayleigh waves would be those waves with the longest periods
No records Found