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Channel waves serve as a tool for the detection of discontinuities in coal seams caused, for example, by tectonic faulting. In this paper we study Love waves propagating along two-dimensional discontinuous coal seams. Synthetic seismograms, computed with an explicit finite difference method, are presented for three types of discontinuities: the seam end, the horizontal and the vertical offset. In all cases the discontinuity reflects mainly those waves with short wavelength and transmits those waves with large wavelength. An additional damping term is introduced into the finite difference formulation in order to prevent reflections from the edges of the computational grid. The boundary conditions at interfaces are all approximated with a truncation error of second order.
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