Landslide Zoning Using the Principal Component Analysis on Monitoring Data: The Sauna Earth Slide—Earth Flow (Parma, Italy)

In this contribute, we present the morphodynamic zoning of the Sauna complex earth slide—earth flow (Corniglio municipality, Northern Apennines) obtained by integrating results of field surveys and of Principal Component Analysis (PCA) of continuous displacement monitoring data. Since January 2014, the area is surveyed by an Automated Total Station (ATS) monitoring 30 prisms with duty cycles of 2 h. An evacuation plan has been adopted by the local authorities, which is based on pre-defined movement thresholds. However, during more than 2 years of monitoring, the results have evidenced that in different zones of the slope, differentiate displacement rates and timings of response to precipitations take place. Therefore, in order to fine tune evacuation plans, movement thresholds should be more appropriately tailored on the basis of morphodynamic zones rather than being left spatially generic. The final result is a morphodynamic zonation of the slope that represents a useful document to identify areas in which differentiated movement thresholds can be assessed for alert and alarm.