HIGH RESOLUTION HYDROGEOPHYSICAL IMAGING AND CHARACTERISATION

Geophysical methods are important tools for a wide range of geological, hydrogeological, and engineering investigations. Conventional processing techniques for electromagnetic tools often use approximations that may be either inappropriate or only provide limited resolution. Higher resolution images can be derived by using more sophisticated approaches that explicitly take into account the electromagnetic wave propagation characteristics. Here, three relatively new developments to obtain high resolution images of quantitative medium properties are discussed: 1) electromagnetic induction (EMI) calibration using apparent electrical conductivity modeling based on electrical resistivity tomography, 2) dispersion inversion of ground-penetrating radar (GPR) data recorded across surface waveguides, and 3) fullwavefield inversion of crosshole tomographic GPR data.