Reconstruction of a colluvial body using geoelectrical resistivity

We reconstructed a colluvial fill in a relict gully on the middle slope of a loess covered area of the Pleiser Hügelland near Bonn, Germany. The morphology of the site gives no indication of the existence of such a feature, and we adopted geoelectrical soundings as a means of both detecting and delineating it. Promising results showed that the electrical resistivity of colluvium and its parent material differs by up to 50%. The volume of the colluvial body has been reconstructed with the aid of a series of soil augerings. The volume of the linear feature perpendicular to the slope was calculated as 2,641 m3 ± 383.05 m3. Though it is small in size we argue that the existence of a colluvial body in such an unexpected slope situation has implications for reconstruction of long-term landscape evolution and for closure of long-term sediment budgets.