Research objectives and content The Fennoscandian Shield makes up a nearly perfect natural laboratory for studying the electrical properties of the deep lithosphere-asthenosphere system. The upper crustal conductivity zones are largely known and the remaining resistive units constitute windows through which electromagnetic fields can penetrate without excessive damping. At high latitudes, a severe limiting factor for upper mantle studies is the proximity of the source region of the inducing electromagnetic fields. However, the source field inhomogeneities can be measured directly by a 2D-array and consequently their effects become part of the modelling. Such an experiment, the Fennoscandian magnetotelluric array, is planned for summer 1998 as major part of the EUROPROBE/SVEKALAPKO project. By the use of a magnetotelluric array of 7x7 stations (900 x 900 km2) with simultaneous measurements, it will become possible to get a rather detailed knowledge about the gross electrical conductivity of the upper mantle, largely unbiased by source field effects in contrast to previous attempts in Fennoscandia and elsewhere in the world. The applicant M.E., experienced with Greenland magnetometer data, shall evolve techniques to realize the data processing and interpretation concerning the aspect of full source field control . Training content (objective, benefit and expected impact) The training contains methodical approaches to take inhomogeneous sources into account, advanced magnetotelluric data processing, related model studies using thin-sheet techniques as well as multidisciplinary interpretation. Links with industry / industrial relevance (22) The Fennoscandian array is part of the EUROPROBE project, mainly aimed to basic research, industrial linkage is given by development and improvement of instrumentation.