This preprint was accepted July 6, 2007
ABSTRACT: New exact solutions, describing acoustic surface waves propagation on an arbitrarily layered structures are constructed via a straightforward separation of variables. Attention is paid to solutions of a moderate growth in lateral variables, $x$ and $y$, of which two particular cases are considered in detail. First, these are solutions with a plane wavefront $x=const$, but with polynomial dependencies of amplitudes on $x$ and $y$. Second, these are solutions describing beams of surface waves exhibiting a high degree of localisation inside a given sector. Dependencies of such a wave fields on parameters are demonstrated by a numerical simulation. Also, solutions which are inhomogeneous plane waves with respect to lateral variables and their polynomial-amplitude generalisatios are considered.[Full text: (.ps.gz)]