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We present a 1:25,000 scale map of the coseismic surface ruptures following the 30 October 2016 M-w 6.5 Norcia normal-faulting earthquake, central Italy. Detailed rupture mapping is based on almost 11,000 oblique photographs taken from helicopter flights, that has been verified and integrated with field data (>7000 measurements). Thanks to the common efforts of the Open EMERGEO Working Group (130 people, 25 research institutions and universities from Europe), we were able to document a complex surface faulting pattern with a dominant strike of N135 degrees-160 degrees (SW-dipping) and a subordinate strike of N320 degrees-345 degrees (NE-dipping) along about 28km of the active Mt. Vettore-Mt. Bove fault system. Geometric and kinematic characteristics of the rupture were observed and recorded along closely spaced, parallel or subparallel, overlapping or step-like synthetic and antithetic fault splays of the activated fault systems, comprising a total surface rupture length of approximately 46km when all ruptures were considered.

Debris flows represent dangerous occurrences in many parts of the world. Several disasters are documented due to this type of fast-moving landslides; therefore, natural-hazard assessment of debris flows is crucial for safety of life and property. To this aim, much current work is being directed toward developing geotechnical-hydraulic models for the evaluation of debris flow susceptibility. A common base for such current models is parameterization of background predisposing and triggering factors such as inherent characteristics of geo-materials, topography, landscape and vegetation cover, rainfall regime, human activities, etc. which influence the occurrence of these processes on slopes. The same factors are also taken into account in soil erosion prediction models. Consequently, it seems worth investigating the effectiveness of the soil erosion index as debris flows susceptibility indicator. To this aim, a logistic regression analysis was carried out between the erosion index assessed by means of the Revised Universal Soil Loss Equation (RUSLE) model and the inventory of debris flows that have occurred in an area in Sicily (Southern Italy). Model assumptions were verified and validated by means of a series of statistical tools. Different possible scenarios were also evaluated by considering hypothetical changes in soil erosion rate under different rain erosivity conditions. Notwithstanding the rough approximations in model data collection, the outcomes appear encouraging. © 2014, Springer-Verlag Berlin Heidelberg.

Messina area (Italy) range stretches along the coast and have high relief energy. Huge rainfall events cause rapid gravitational phenomena classified as debris flows. The rampant urbanization developed in the last decades in the Messina Municipality has determined a fragile territorial settlement, prone to be heavily damaged by debris flows, as in October 2009. In order to support the community in tackling the risk conditions which it is subjected to, it is necessary to develop “non-structural” measures, characterized by a high level of environmental sustainability. The scientific community and the public authorities responsible for land management and involved in the mitigation of the geomorphological risk are paying a specialattention to the development of monitoring and alarm systems able to improve the current civil defence plans. Based on the historical information on rainfall, this study deals with the triggering thresholds of debris flows. The results provide additional elements to the knowledge of the critical rainfall, useful for developing effective early warning systems. . © Springer International Publishing Switzerland 2015.

October 1st 2009 a heavy rainfall caused more than one thousand debris flows in two small basins south of Messina town (North–East Sicily, Italy). After the disaster Messina Municipality entrusted the risk assessment of its whole territory to a geomorphology and GIS team, led by ENEA, that applied and improved a heuristic method aimed at the identification of the areas prone to landslide triggering, based on the recognition of physical and dynamical characteristics of phenomena. This landslide susceptibility method is a GIS based process that consists in four steps: Field Survey, Site Analysis, Macro-Area Analysis and Susceptibility Analysis. Through the Field Survey of natural and anthropic conditions of past and recent phenomena a landslide inventory is generated, and each thematic map is stored in a GIS database. In the Site Analysis a univariate statistical analysis of the inventory leads to classify each causative factor as a discriminating parameter (condition necessary for slope instability) or as a pr edisposing factor (condition that works together in worsening slope stability). In the Macro-Area Analysis the GIS overlay of all thematic maps is performed to recognize, in surrounding areas, features similar to those of past events. Finally a susceptibility function runs the weighted sum of Predisposing Factors in zones where all Discriminating Parameters are present, deriving the Susceptibility Map. The here discussed heuristic GIS method allows the integration of multidisciplinary knowledge, both quantitative and qualitative, thus exploiting field experience. . © Springer International Publishing Switzerland 2015.

The analysis of the triggering thresholds is aimed at answering the question of when an event can take place. Based on the historical information on rainfall—the main triggering factor of this type of landslides—the triggering thresholds of debris flows have been investigated with the aim to provide additional elements to the knowledge of the critical rainfall. Nevertheless, the most directly factor related to the triggering of debris flows is the soil moisture level that depends not only on the intensity of rainfall in a given moment, but also by the thermoprecipitation regime of the previous period. The state of soil saturation was analysed in this study in laboratory with the pressure plate extractors techniques and monitored in field by the FDR probes. The responses of the FDR probes seem to confirm the data modelling, showing in some cases a marked sensitivity to the rainfall input. Coupling rainfall and soil water content data, the study would give a contribution to the development of more effective early warning systems. . © Springer International Publishing Switzerland 2015.

Through the recording of historical and recent events data, three different landslides inventory of the Messina town territory have been created. The first collects information about localization and date of historical landslides occurred between the XVI century and 2011. The second collects ground effects induced by the 1908 earthquake registered in numerous technical reports compiled by expert researchers and technicians of that time. The third gathers recent landslides and was carried out through field activities, by reviewing aerial photographs for the years 2007 and 2009 and by analysis of Google satellite images. These three landslides inventories represent a source of specific information, essential for the knowledge and the analysis of the territory. They represent a valid tool not only for experts in the sector but also for everyone who faces the issues linked to the geomorphologic risk assessment. Nevertheless the information on the landslide characteristics constituted the basis for the definition of the landslide susceptibility map and landslides’ trigger rainfall thresholds of the area. . © Springer International Publishing Switzerland 2015.

Favignana island (Sicily, Italy) is a historical and environmental attraction site frequented by tourists during the long warm season of the year. For several centuries the calcareous sandstone outcropping in the east side of the island has been extracted and used as building stone. Actually the quarries and the caves are undergoing to erosional and gravitational processes that are influencing the touristic use. As well as putting at risk the safety of people attending the area, the diffused rock falls are likely to jeopardize sites of great anthropological value that, once destroyed, can no longer be reconstructed. An integrated monitoring project of the cliffs is aimed to identify the most active areas and to provide support to the local government’s policies in the implementation of mitigation measures. If adequate measures will be taken in the future, operators and users of the tourist circuit will have the opportunity to enjoy these amazing areas with lower level of landslide risk. © Springer International Publishing Switzerland 2015.

Mud and debris flows constitute a serious threat for several Italian regions as attested by recent several disasters attributable to such phenomena. The adoption of effective mitigation measures is complicated by the difficulty in predicting spatial and intensity features of future events. This paper applies a practical application of debris/mud flows hazard assessment in the area of Messina province. The study was based on an inventory of several debris flows triggered by heavy rainfall occurred in the Giampilieri and Briga catchments after the event of October 1, 2009. Data elaboration was focused on mapping source areas and on assessing the runout of landslides and their intensity. An evaluation of the factors that make the area prone to these events was used as input for a GIS based hazard prediction model. © Springer-Verlag Berlin Heidelberg 2013.