Geoelectrical structure across the Bohemian Massif and the transition zoneto the West Carpathians

Geoelectrical methods of magnetotelluric (MT) and geomagnetic deep sounding s (GDS) were employed to infer the electrical conductivity structure at dep ths of specific regions of the Bohemian Massif (BM) and in the transition z one between the BM and the West Carpathians (WCP). Transfer functions betwe en components of temporal variations of the natural electromagnetic field i nduced in the Earth by external sources were estimated and converted to ele ctrical conductivity (resistivity) profiles. While the results from other r egions of the BM are noted in references, the emphasis hen is placed on the new analysis of MT/GDS data at field stations along the regional almost 50 0-km long Deep Seismic Sounding profile No. VI traversing the country from NW to SE. Inversion of its results suggests a complex,geoelectrical structu re, characteristic for each geological unit, with layers or increased elect rical conductivity at crustal and uppermost mantle depths. The results also indicate strong fields of anomalous induction marking geoelectrical inhomo geneities at the eastern margin of the BM and in the foreland of the WCP. ( C) 2001 Elsevier Science B.V. All rights reserved.