We use the Born approximation of the perturbation method to solve the problem of scattering of a harmonic Rayleigh surface acoustic wave by a weak-contrast inhomogeneity that is small compared with the wavelength and is located in a solid half-space near its boundary. The material of the inhomogeneity differs from the material of the half-space only in its density. The Rayleigh wave incident on the inhomogeneity is excited by a monochromatic surface force source acting normally to the half-space boundary. We derive expressions for the displacement fields in the scattered spherical compressional and shear (SV- and SH-polarized) waves. Scattering of the Rayleigh wave into a Rayleigh wave is studied in detail. We find expressions for the vertical and horizontal components of the displacement vector in the scattered Rayleigh wave as well as its radiated power. It is shown that the field of the scattered surface wave is mainly formed by vertical oscillations of the inhomogeneity in the field of the incident wave. In this case, the radiated power for the scattered Rayleigh wave formed by vertical motion of the inhomogeneity in the incident-wave field depends on the depth of the inhomogeneity as the fourth power of the function describing the well-known depth dependence of the vertical displacements in the Rayleigh surface wave. Correspondingly, the dependence of the radiated power for the scattered Rayleigh wave formed by horizontal motion of the inhomogeneity depends on its location depth as the fourth power of the depth dependence of the horizontal displacements in the Rayleigh surface wave. We perform calculations of the ratio between the powers of the scattered and incident Rayleigh waves for different ratios between the velocities of the compressional and shear waves in a solid. It is shown that the radiated power for the scattered surface wave decreases sharply with increasing depth of the subsurface-inhomogeneity location. Thus, the scattering of a Rayleigh wave into a Rayleigh wave is fairly efficient only when the location depth of the inhomogeneity does not exceed about one-third of the wavelength of the shear wave in an elastic medium.
Similar content being viewed by others
References
K. Aki and P.Richards, Quantitative Seismology, Vol. 1, W.H. Freeman, San Francisco, Ca. (1980).
K. Aki and P.Richards, Quantitative Seismology, Vol. 2, W.H. Freeman, San Francisco, Ca. (1980).
L.P.Geldart and R. E. Sheriff, Exploration Seismology, Cambridge Univ. Press, New York (1995).
I. A. Viktorov, Surface Sound Waves in Solids [in Russian], Nauka, Moscow (1981).
S. V. Biryukov, Yu. V.Gulyaev, V. V. Krylov, and V. P. Plessky, Surface Acoustic Waves in Inhomogeneous Media [in Russian], Nauka, Moscow (1991).
L. M. Brekhovskikh, Waves in Layered Media, Academic Press, New York (1960).
L. A.Chernov, Waves in Random Media [in Russian], Nauka, Moscow (1975).
G. F. Miller and H. Pursey, Proc. Roy. Soc. A, 233, No. 1192, 55 (1955).
V. B. Gushchin, V.P.Dokuchaev, Yu. M. Zaslavsky, and I.D.Konyukhova, in: A.V. Nikolaev, ed., Study of the Earth by Nonexplosive Seismic Sources [in Russian], Nauka, Moscow (1981), p. 113.
G. I. Petrashen’, in: Problems of the Dynamic Theory of Seismic Wave Propagation [in Russian], Nauka, Leningrad (1978), No. 18, p.1.
E. L. Shenderov, Radiation and Scattering of Sound [in Russian], Sudostroenie, Leningrad (1989).
L.R. Johnson, Geophys. J. Roy. Astron. Soc., 37, 99 (1974).
A. V. Razin, Acoust. Phys., 55, No. 2, 225 (2009).
L.D. Landau and E. M. Lifshitz, Theory of Elasticity, Pergamon Press, New York (1986).
L. B. Felsen and N.Marcuvitz, Radiation and Scattering of Waves, Prentice-Hall, Englewood Cliffs, N. J. (1973).
V.P. Dokuchaev, Izvestiya, Phys. Solid Earth, 32, No. 1, 67 (1996).
V.P. Dokuchaev, Izvestiya, Phys. Solid Earth, 35, No. 4, 343 (1999).
G. A. Maksimov, Izvestiya, Phys. Solid Earth, 32, No. 11, 876 (1996).
V. S. Averbakh and Yu. M. Zaslavskii, Izvestiya, Phys. Solid Earth, 34, No. 1, 43 (1998).
G. A. Maximov, M. E. Merkulov, and V. Yu. Kudryavtsev, Acoust. Phys., 49, No. 3, 328 (2003).
Yu. M. Zaslavskii, Acoust. Phys., 50, No. 1, 46 (2004).
A.V. Razin, “Radiation of Rayleigh and Stoneley waves by distributed subsurface sources” Preprint No. 530 [in Russian], Radiophys. Research Inst., Nizhny Novgorod (2009).
A. V. Razin, Radiophys. Quantum Electron., 53, No. 2, 82 (2010).
M.V. Fedoryuk, Saddle Point Method [in Russian], Nauka, Moscow (1977).
V.P. Dokuchaev and A. V. Razin, Izv. Akad. Nauk SSSR, Fiz. Zemli, No. 10, 81 (1990).
V.T. Grinchenko and V.V.Meleshko, Harmonic Oscillations and Waves in Elastic Bodies [in Russian], Naukova Dumka, Kiev (1981).
A. V. Razin, Izv. Akad. Nauk SSSR, Fiz. Zemli, No. 12, 100 (1991).
E. I. Urazakov and L.A. Fal’kovskii, Sov. Phys. JETP, 36, 1214 (1973).
A. A.Maradudin and D. L. Mills, Appl. Phys. Lett., 28, 573 (1976).
Yu.M. Zaslavsky, “Energy of scattered elastic fields arising due to diffraction of a Rayleigh wave on a surface perturbation of a semibound medium,” Preprint No. 267 [in Russian], Radiophys. Res. Inst., Nizhny Novgorod (1989).
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 53, No. 7, pp. 464–480, July 2010.
Rights and permissions
About this article
Cite this article
Razin, A.V. Scattering of a Rayleigh surface acoustic wave by a small-size inhomogeneity in a solid half-space. Radiophys Quantum El 53, 417–431 (2010). https://doi.org/10.1007/s11141-010-9239-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11141-010-9239-3