Resonance waves in media with unwelded boundaries

It is shown that in layered media with weakened interfaces, resonance waves (Kr-waves) arise. Such waves have characteristic frequencies, and many other kinematic and dynamic features distinguish them from well-known Love and Rayleigh type waves. Comparison of theoretical results with experimental seismic data indicates that Kr-waves can be formed in real geological sections. We show theoretically and numerically that in a sedimentary basin of finite lateral extent, a horizontal Kr-wave can be trapped and resonates. This wave has a number of interesting properties: the wave spectrum has a resonance frequency, the wave group velocity is equal to an intermediate value between the shear and longitudinal velocities; the attenuation of the wave increases as the frequency varies from the resonance value. Bibliography: 5 titles. © 2008 Springer Science+Business Media, Inc.