Detection of Old Workings, Sinkholes, Underground Fires and Acid Mine Pollution Using Geophysics and Airborne Thermal Infrared Imagery
Field trials at four collieries comparing ground and airborne geophysical methods, with case studies and an applications guideline for the Witbank and Highveld collieries.
by Michael van Schoor | March 2002
Micro-gravity, electrical resistivity and time domain electromagnetics located the boundary between old workings and virgin ground, but no ground technique tested could resolve individual bords and pillars at the depths typical of the Witbank and Highveld coalfields. Airborne thermal infrared surveys worked well as a low cost regional reconnaissance tool for shallow sinkholes, fires and possible pollution plumes.
R1500,00
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