(1) School of Earth Sciences, Flinders University of South Australia, GPO Box 2100, 5001 Adelaide, SA, Australia;(2) Department of Engineering Science, University of Oxford, Parks Rd, OX1 3PJ Oxford, U.K.
Abstract:
Guided seismic waves are generated at lateral discontinuities in coal seams as an integral part of the mechanics of scattering downgoing body waves from a surface energy source.Numerical and laboratory model studies undertaken for both thin and thick coal seam waveguides show that small faults generate recognizable diffraction patterns by convertingP andS waves into channel wave arrivals at in-seam geophones on a walkawayVSP profile.These results suggest that in-seam geophones can be used during subsequent surface reflection surveys so as to improve mine profitability by optimising longwall layout in faulted ground.