The radiation patterns of P and S waves from a spherical cavity, in an infinite elastic medium on which the stress similar to a single couple force acts, were obtained by J. G. J. Scholte and A. R. Ritsema (1962). In this paper the solution for their model is presented in the case when a step function is assumed as the time variation of the stress.
As a result, it is found that the wave form of S waves depends on θ in spherical coordinates (r, θ, ø). Generally speaking, the orbit of the particle motion of S waves is not linear. Also the radiation pattern of S waves is similar to that for Type II rather than for Type I force system.