Signal processing for crosshole seismic imaging

Abstract

Boreholes are normally drilled on a wide grid pattern over potential coal mine sites to evaluate coal reserves, etc., but further drilling or geophysical methods are required for detailed coal seam mapping. Surface seismic methods are useful to find seam conditions without drilling, but are limited by the low frequencies used (<150 Hz even for high resolution surveys) to resolutions of the order of 10 m, which is inadequate for good mine planning. Higher frequencies cannot be transmitted through the surface soil and weathered layers.