The transmission and reflection of a Rayleigh wave through a step on a homogeneous half-space of Poisson's ratio σ = 0.253 have been investigated by a seismic models method. The experimental results show good agreement with numerical ones obtained by finite-difference calculations when the wave is incident onto a downward step. Phase shifts are given both for the upward and downward steps. The characteristics of the transmitted wave do not depend much on the direction of propagation but those of the reflected wave are clearly direction-dependent. In each case the transmission and reflection coefficients and phase shifts depend on the ratio of step height to wavelength.

The group delays are calculated and they are positive or negative depending on the period. About 80 per cent of the incident energy is converted into body waves when the step is higher than 0.3 times the wavelength of the Rayleigh wave.

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