  We investigate the propagation of transverse elastic waves in crumpled media.
We set up the wave equation for transverse waves on a generic curved, strained
surface via a Langrangian formalism and use this to study the scaling behaviour
of the dispersion curves near the ridges and on the flat facets. This analysis
suggests that ridges act as barriers to wave propagation and that modes in a
certain frequency regime could be trapped in the facets. A simulation study of
the wave propagation qualitatively supported our analysis and showed
interesting effects of the ridges on wave propagation.
