Quantitative 2D VLF data interpretation
نویسنده
چکیده
Ž . The ability of the VLF-R Resistivity method to provide quantitative subsurface resistivity information is examined. The Ž . frequencies used in conventional VLF 15 to 30 kHz provide the deepest penetrations of the multi-frequency, extended method of RadioMT. Both methods are considered. VLF data, being effectively single frequency, are insufficient to resolve Ž . Ž . one-dimensional 1D vertical structure in any detail. At the site investigation scale, however, it is the departures from the Ž . background vertically uniform structure that are of interest. Improved methodologies for the quantitative assessment of VLF data derive from advances in regularised inversion techniques. Hydrogeological and waste-site examples of VLF-R Ž . survey data, aided by wide-band VLFrRadioMT synthetic modelling and inversion studies, are used to illustrate their Ž . shallow 0 to 20 m resolution capabilities in conductive environments. q 2000 Elsevier Science B.V. All rights reserved. Ž .
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