In-seam seismic application for detecting inhomogeneties in coal seams - a review

Mechanized coal winning systems require thorough knowledge of seam structure for planning of layout as well as selection of machines. In-seam seismic method can be used to study seam structure, thereby existence of inhomogeneties such as faults, dykes, sills, thinning of seams, washouts, etc. The basic principle of in-seam seismic technique involved survey of reflected and refracted seismic waves to detect the inhomogeneties. Among the two types of seam waves that are Rayleigh-type and Love-type, the latter is of more practical interest in in-seam seismic method. The paper describes the the principles by which the various inhomogeneties can be detected in the coal seams.