Publication Date:
2019
Description:
〈span〉〈div〉Summary〈/div〉The paper focuses on the propagation of low-frequency pseudo-Rayleigh and pseudo-Scholte waves at the liquid/soft porous sediment interface with an underlying hard porous sediment half-space. The overlying liquid is assumed to be ideal compressible medium and the porous sediments are modelled by Biot theory. Based on the boundary conditions, the closed-form dispersion equations of far-field interface waves are deduced using 2-D Helmholtz decomposition theorem and Fourier transform. The velocity and attenuation of pseudo-Rayleigh and pseudo-Scholte waves are determined by Newton iteration in a reasonable rooting interval. The analytical expressions of the displacement field and liquid pressure distribution caused by interface waves are also derived. Then, the dispersion equations for four degenerate systems are derived as special cases by assuming the thickness of the liquid layer or the sandwiched porous soft sediment layer to be zero or infinite. Lastly, numerical examples are used to verify the degeneracy of the system and to analyse the propagation characteristics of pseudo-Rayleigh and pseudo-Scholte waves. They show the dependences of the velocity and displacement field on dimensionless modulus and dimensionless wavelength. When the dimensionless wavelength is small or very large, the phase velocity and displacement field calculated by the present system is the same as the special cases, thus proving the validating of the new system.〈/span〉
Print ISSN:
2051-1965
Electronic ISSN:
1365-246X
Topics:
Geosciences
Published by
Oxford University Press
on behalf of
The Deutsche Geophysikalische Gesellschaft (DGG) and the Royal Astronomical Society (RAS).
