Application of the ERT to recognise the geological structure of frost-riven cliffs localised in the Skalny Potok (Hruby Jesenik Mts.)

In the area of the Skalni Potok Nature Reserve (Hruby Jesenik), studies of gneissic cliffs were carried out to determine the role of lithology in the process of their formation. The research included geometric measurements of vertical discontinuity zones of selected rock outcrops and the electrical resistivity tomography (ERT) measurements of strongly weathered subsurface layers. As a result of the measurement, the orientation of the main crack systems (NW-SE and NE-SW) responsible for the location of cliffs within the Skalni Potok Valley was obtained. In addition, the main crack directions for the gneiss occurring in the studied mountain region were identified. Interpretation of the ERT models allowed to characterise the structure of the rock mass, including the reach of the rainwater infiltration level and the depth of the weathering front.