Electrical resistivity tomography investigations on a paleoseismological trenching study

• 2D ERT is carried out as a tool for determination of suitable trench location.
• Various electrode configurations and intervals of ERT application were tested.
• Trench results are correlated with 2D ERT sections.
• The success of the ERT method and usage of the mixed data set are presented.
• Relative sensitivity values to appraise the DOI of the ERT images are given.

Two-dimensional electrical resistivity tomography (ERT) investigation was performed in a paleoseismological trenching study. Data acquisition strategies such as the selection of electrode configuration and electrode intervals of ERT application were investigated in this paper. The ERT results showed that the Wenner and Wenner–Schlumberger arrays yielded similar results for subsurface characteristics whereas the DD array provided slightly different results. The combined usage of these arrays produced satisfactory images of the subsurface resistivity distribution. In addition, the electrode spacing tests revealed that a suitable interpretation of subsurface geology can be obtained from a 5 m electrode interval. However, a suitable trenching location defined by successful 2D resistivity models was obtained for 1 m electrode spacing. Therefore, the comparison of the trench and ERT results was also possible. The results of trenching and ERT studies substantially support each other.