Scattering of SV waves by a cavity in a layered half-space was analyzed by indirect boundary element method in frequency domain. The free-field displacements and stresses were calculated on the line which will form the surface of the cavity. Then fictitious distributed loads were applied on the same line to calculated Green’s functions for displacements and stresses. The amplitudes of the fictitious distributed loads were determined by the boundary conditions

and the displacement response arising from the waves in the free field and from the fictitious distributed loads were then summed up to obtain the solution. The amplification of the incident SV waves by a cavity in a homogeneous and a layered half-space were compared; and numerical results showed that larger surface displacement amplitude may be resulted in the case of layered half-space

especially for low-frequency waves.