Mapping the soil-bedrock interface in the Alluvial Argive Basin (Greece) with TEM soundings

The importance of determining the shape of the soil-bedrock interface in the alluvial Argive Bain, Peloponnese, Greece, stems on the fact that it is a fundamental in a current seismic ground response analysis in areas around the archaeological sites of Midea and Tiryns, the later listed by the UNSECO as world heritage. Although newly collected Transient Electromagnetic (TEM) soundings were modeled and inverted in one-dimension (1D) and used to create two-dimensional (2D) pseudo-sections and maps of resistivity distribution at several depth intervals. This pseudo-2D and -3D imaging procedure has been successful in other alluvial basins allowing inferences of their structure. The 1D inverted models were stitched together to form thirteen 2D geoelectrical resistivity pseudo-sections, some traversing the whole basin. Additionally, the 1D models were interpolated to form maps of resistivity distribution at various depth intervals from 0 to 130 m depth. The previously uncertain soil-bedrock contact outside populated zones within the Argive Bain leading to soil thickness varying from 20 to at least 130 m thick in some areas. The bedrock is uplifted in some areas and highly fractured in others.