Geoelectric measurements in claystone for exploration of anomolous zones

Underground excavations provoke micro- and macrofractures in the vicinity of drifts and galleries. A detailed knowledge of this excavation damaged rock zone (EDZ) is indispensable for the planning and dimensioning of geotechnical barriers for underground ultimate waste disposals in particular that for chemical, toxic and radioactive wastes. The host rock as well as the artificial, geotechnical barrier should avert any propagation or trespassing of virulent and radioactive substances. Still different geophysical methods are tested and adapted to find out the best assessment strategy for each kind of host rock. Seismics [1], microacoustics [7] and geoelectrics [8, 9, 10] turned out to be the most promising methods in claystone. Since the beginning of 1999 also complex valued geoelectric measurements underground in tunnels the have been successfully conducted