Geoelectrical tomography as an operative tool for emergency management of landslide: An application in basilicata region, Italy

During the landslide emergency many kinds of data, even if preliminary, can help to better understand the complexity of the investigated phenomenon and to give a valid contribution to the successive damage valuation. The electrical resistivity tomography (ERT) method was applied for investigating the deep characteristics of a landslide body that occurred in March 2006 close to Potenza town in Basilicata region (southern Italy): the landslide slid on a road near some farmers' houses which had to be evacuated. The information obtained by the application of this indirect technique appeared to be particularly useful for end users involved in the risk management. The high resolution of the 2D ERT technique allowed the detection of possible sliding surfaces and the characterization of high water content areas in which the increase of the saturation degree and of pore pressures could cause a weakening of the slopes and a reactivation of the movement. Due to the comparison between ERT results and stratigraphical data from boreholes carried out in the area it was possible to decide on the adoption of other evacuation decrees.