Detection of Old Workings
Review of earlier geophysical work plus literature, setting out method selection and test site requirements ahead of field trials, for engineers assessing undermined ground before development.
by M van Schoor | February 2008
Microgravity, resistivity based methods including self potential, and time domain electromagnetics are identified as able to detect and delineate shallow old workings, with controlled source audio magnetotellurics useful below about 30 metres. How well each performs depends on target depth, the material filling the void and the overburden, and has never been quantified. Field trials were planned to close that gap.
R1500,00
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