Abstract:In this paper, the problem of equivalence of a pressurized cavity and a center of explosion in the generation of seismic waves is first discussed. The displacement field caused by an explosion in a spherical cavity situated in a layered medium is then calculated by first finding the impulse response of the medium and then con-volving it with the equivalent point source function.For a homogeneous half space, the transient solution for the displacement of the free surface is determined by three dimensionless parameters in terms of which the exact solution for the far field is found and the motion near the explosion is also discussed. Finally, the formal solution for the spectrum of the surface displacement caused by a cavity explosion in a layered medium is derived.