In the area of the landslide that was triggered after a longer period of heavy rainfall in May 2023 in the village of Rotman, municipality of Juršinci, we measured several geoelectrical profiles in transverse and longitudinal directions using the electrical resistivity tomography (ERT) method. The measurements provided data on the spatial distribution of electrical resistivity, which is influenced, among other factors, by lithological composition, sediment grain size, porosity, and water content. The measurements were carried out during a dry period and then repeated after intense short-duration rainfall along the same profiles, with the aim of checking for possible changes in the resistivity distribution and identifying the potential formation of perched groundwater horizons and preferential infiltration pathways of rainwater.
The study revealed zones of different resistivity within the landslide. Lower electrical resistivity values are primarily associated with fine-grained sediments, whereas higher values indicate coarser-grained sediments. The spatial distribution of electrical resistivity points to a heterogeneous internal structure of the landslide and its variable thickness.
Based on the interpretation of the ERT data, we can conclude that the landslide slip surface most likely developed at the contact between fine-grained and coarse-grained sediments. A comparison of measurement results under different hydrological conditions did not show sufficiently clear changes in the resistivity distribution to allow identification of the formation of possible perched groundwater horizons or preferential infiltration pathways of rainwater.
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