Application of electrical resistivity tomography in assessing complex soil conditions

Appropriate assessment of spatial variation of soil and hydrogeological conditions is a crucial issue in recognizing foundation soil. The best methods to achieve this goal are those that supply continuous rather than scattered data on soil medium variation. Electrical resistivity was measured with the resistivity cone penetration test (RCPT) and electrical resistivity tomography (ERT) with electrodes spaced at 1 and 3 m in order to discriminate peat layers beneath low-resistivity clays. Soil conditions determined by drillings and ERT were not concordant, therefore resistivity modelling of the medium was conducted based on geological units determined by drillings and values of apparent resistivity obtained from RCPT. The strata thickness and electrode spacing is shown to have an influence on resistivity imaging in complex soil conditions.