Electronic Journal Technical Acoustics ISSN 1819-2408

Yu. M. Zaslavsky, V. Yu. Zaslavsky

On an influence of the dispersion on the propagation of surface Rayleigh waves

language: Russian

received 09.11.2011, published 24.11.2011

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ABSTRACT

The surface Rayleigh waves propagated along the boundary of the half-space covered by thin layer with different density, that causes a phase velocity dispersion similar to the interferential waves, are analyzed. The dispersion equation for these waves are derived that permits to plot the curve of frequency dependence of the wave phase velocity. As applied to the medium model of the layer on the half-space and to the pulse impact the calculation, formulas for the wave responses in the remote surface points are derived. That further used for the construction of the time dependence of the response. Presented illustrations show that some effects occur by the growth of the source-receiver distance. The increasing of the duration of the wave response on the pulse action, the increasing of the time delay of the wave appearance and the decreasing of the surface wave level are accompanying the wave propagation.

Key words: surface Rayleigh waves, inhomogeneous layer, frequency dispersion, phase velocity, pulse impact, wave response.

11 pages, 4 figures

Сitation: Yu. M. Zaslavsky, V. Yu. Zaslavsky. On an influence of the dispersion on the propagation of surface Rayleigh waves. Electronic Journal “Technical Acoustics”, http://www.ejta.org, 2011, 13.

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		Yuriy Mikhaylovich Zaslavsky graduated radio-physical faculty of N.Novgorod University (1966), doctor of science, leader scientist at the Institute of Applied Physics Russian Academy of Science. Scientific interests: acoustic and seismic wave propagation and radiation of these waves by coherent vibration sources, generation of seismic waves with sharp space-angle directivity on the base of phase arrays, the seismic signal reception, acoustic probing of heterogeneous in bowels of the earth, developing of the approaches for the enhancement of hydro-carbonates seismic probing efficiency. e-mail: zaslav(at)hydro.appl.sci-nnov.ru
		Vladislav Zaslavsky - PhD, Radiophysical faculty of Nizhny Novgorod State University. e-mail: zas-vladislav(at)appl.sci-nnov.ru