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The present paper illustrates the results of an integrated study of a large landslide located on the southern slope of Mount la Civita (Molise, Southern Apennine), an E-W elongated, SSE dipping and 890-m-high monocline carbonate ridge. The upper part of the slope affected by the landslide is largely controlled by strata attitude while its basal part is marked by a strike-slip fault causing the tectonic juxtaposition of the carbonate successions against predominantly clayey flysch units. An integrated study, including geological, geomorphological and geotechnical investigations, was carried out to determine the features of the landslide and to plan further investigation and monitoring. In particular, from 2002 to 2004, Differential Global Positioning System monitoring and core drillings, coupled with inclinometer measurements, were carried out to determine the landslide's kinematics, extent, depth to the surface of rupture and rates of movement. Inclinometer data revealed the presence of the rupture surface at a depth of about 20 m. DGPS monitoring allowed rates of movement up to several tens of centimetres per year to be recorded. The nearby village of Civitanova del Sannio can still be considered at risk due to the landslide, as recent remedial works, consisting mainly of very shallow re-shaping of the slope by blasting and partial filling of trenches, did not succeed in stopping its movement. © 2012 Springer-Verlag.

A significant part of Campania is extensively covered by volcaniclastic soils, deriving from the alteration of airfall-sedimented formations of layered ashes and pumices that were ejected by Campi Flegrei and Mt. Somma–Vesuvius during explosive eruptions. Where such soils cover steep slopes cut in carbonate bedrock, landforms depend essentially on the morpho-evolution of such slopes prior to the deposition of the volcaniclastic soils, because these are generally present only as thin veneers, up to a few meters of total thickness. Historical records and local literature testify that, in this part of Campania, landslides that originate on carbonate slopes covered by such soils and terminate at their foot or at gully outlets are frequent, following critical rainfall events. Such landslides can be classified as complex, occurring initially as debris slides, but rapidly evolving into debris avalanches and/or debris flows. The localization of the initial sliding areas (i.e. ‘‘sources’’) on the slopes depends on both the spatial distribution of characters of the soil cover and the spatial distribution of the triggering rainfall events. It therefore appears reasonable to separate the two aspects of the problem and focus on the former one, in order to attempt an assessment of soil sliding susceptibility in the event of landslide-triggering rainfall. In this paper, some results of the application of a method aimed at such an assessment are presented. The method, called SLIDE (from SLiding Initiation areas DEtection), is based on the concept that, for a spatially homogeneous soil cover and a spatially homogeneous landslide-triggering rainfall sequence, different values of threshold slope gradient for limit equilibrium conditions exist, depending on morphological characters of the soil cover, such as its continuity and planform curvature. The method is based on the assessment of (1) soil cover presence, (2) discontinuities within soil cover, (3) slope gradients and curvature, by means of good resolution DEMs. It has been applied to sample carbonate slopes of Campania, where landslides originated either repeatedly or recently. Results are encouraging, and a soil sliding susceptibility map of a large area, based on a simplified version of method, is also presented.

InfraRed Thermography has been tested herein for the study of the fracturing condition of intensely jointed rock masses, in order to find out what kind of information can be assessed. Although this technique is widely used in several scientific fields, its direct application for rock mechanics purposes is still under development. In this paper, thermal imaging campaigns, carried out in different climatic conditions, are described. A Cooling Rate Index, related to how fractured rock masses behave during the heat transfer towards the external environment, is proposed. Such an index has been related to the degree of fracturing of the rock masses, in order to find a relationship among thermal behavior and the main quantitative fracturing indexes. Results return interesting matches between some geostructural features and thermal outputs, demonstrating the reliability of the application of such methodology to bare rock masses. Moreover, new experimental considerations are proposed, laying the foundations for future studies aimed to further validate the InfraRed Thermography as an effective remote survey technique.

The application of Infrared Thermography is here proposed as a useful tool for the remote survey of intensely jointed rock slopes. Although such a technique is widely used in several scientific fields, its direct application for the evaluation of the degree of fracturing in bare rock masses is still a pioneering methodology. To test and validate its application, two representative rock masses of different lithologies have been chosen in the southern sector of Peloritani Mountains (north-eastern Sicily). Thermal images were taken during three moments of the same day, to study the thermal behavior of the rock under heating and cooling conditions. Results show interesting matches between some geostructural features and thermal outputs, demonstrating the reliability of such a methodology, which can also allow the extension of the survey to portions of the slope that are not directly reachable.

A complex landslide, which mobilized a calcareous rock mass of about 60,000 m3, occurred on January 3, 2002, along the southwestern slope of Mt. Catiello, above Positano (province of Salerno, Italy). According to established classification schemes, such a landslide can be classified as a rock avalanche or as a complex, dry, extremely rapid rock fall—dry, extremely rapid debris flow. Landslides of this type and dimensions are quite rare in the southern Apennines, and even rarer in the Sorrento-Amalfi Peninsula. Therefore this one represents a singular case for assessing both the mechanisms leading to such a type of sudden, often hazardous mass movements, and the residual hazard still existing on Mt. Catiello. Due to the inaccessibility of the near-vertical rock slopes, the characterization of the instability mechanisms of the landslide was based on analyses of terrestrial stereoscopic photographs, taken from lateral and frontal positions with respect to the 2002 depletion zone, and on measurements/validations of structural settings carried out in accessible sectors of the mountain. Currently, the southwestern slope of Mt. Catiello, which corresponds to the depletion zone of the 2002 landslide, cannot be considered more unstable than the adjacent northern slope, where a smaller rock mass tower, with a volume of 20,000 m3 and clear signs of a propagating deformation-fracturing process at the base, was identified. Considering this remaining unstable rock tower as a part of the mass movement, the distribution of activity of the landslide can be considered as widening, and its state of activity as suspended.