Jan Van der Kruk

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Dispersion of ground-penetrating radar (GPR) waves can occur when they are trapped in a layer. In this paper, we analyze the modal propagation of GPR pulses through a layer of ice that is overlying water. Dispersed transverse electric (TE) waves that are trapped in the waveguide have larger amplitudes than the critically refracted waves that travel through(More)
High-permittivity layers, related to high-porosity layers or impermeable clay lenses, can act as low-velocity electromagnetic waveguides. Electromagnetic wave phenomena associated with these features are complicated, not well known and not easy to interpret in borehole GPR data. Recently, a novel amplitude analysis approach was developed that is able to(More)
Ground-penetrating radar (GPR) data affected by waveguide dispersion are not straightforward to analyse. Therefore, waveguide dispersed common midpoint measurements are typically interpreted using so-called dispersion curves, which describe the phase velocity as a function of frequency. These dispersion curves are typically evaluated with deterministic(More)
There is a new method to measure the thickness of an ice layer of a lake. Contrary to applying common offset GPR measurements, no calibration measurement is needed and contrary to the most conventional method to drill a hole, the ice layer is not destroyed. Therefore no water overflows the ice which is an advantage if activities take place on the frozen(More)
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(More)
Ground Penetrating Radar (GPR) has found widespread application for the non-invasive characterization of the subsurface. Nevertheless, the interpretation of GPR measurements remains difficult in some cases, particularly when the subsurface contains thin horizontal layers with contrasting dielectric properties that might act as waveguides for electromagnetic(More)