Peter Weidelt

Geoelectrical fields in a layered earth with arbitrary anisotropy

In many cases in geoelectrical exploration, the standard model of a layered isotropic half‐space is a good approximation to geophysical reality. But sometimes it is useful to extend this model to uniform anisotropic layers. For example, in regions with distinct dipping stratification, one will try to represent this conductivity variation in the form of dipping anisotropic layers. In this paper, the layered isotropic half‐space is extended to a half‐ space with general anisotropy such that to each layer is assigned a symmetrical (3 × 3) resistivity tensor. After formulating the general layered problem, the numerical implementation is treated. A very fast algorithm exists only if the resistivity tensor is rotationally symmetric around a vertical axis (transverse isotropy). In all other cases, one has to calculate a double integral with respect to the horizontal components of the wavenumber vector. Furthermore, we have also calculated the magnetic field. Whereas in the isotropic case this field does not cont...

Ulrich Schmucker (1930–2008)

Ulrich Schmucker passed away in a Beijing, China, hospital in the early morning of 27 October 2008. Ulrich had been in China to attend the 19th International Workshop on Electromagnetic Induction in the Earth, a biannual workshop he had helped found and had attended for more than 30 years without fail.

Geophysical In-situ Groundwater and Soil Monitoring

The area around both vulnerable sites (e.g., waterworks) and hazardous sites (e.g., landfills and industrial plants) have to be monitored for contaminants. The integrity of contaminant barriers and the success of rehabilitation of contaminated sites must also be monitored. The spread of contaminants occurs via three paths: water, soil, and air. Of these, groundwater and surface water are the most significant.