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Abstract: The proposed experimental study is aimed at contributing to the landslide susceptibility evaluation using a multidisciplinary approach: geological, geomorphological and geo-engineering survey, together with multivariate statistical analysis and GIS technique. It is included in a wider research project, aimed at defining the landslide hazard in the area of the map no. 250 “Castelnuovo di Garfagnana” (1:50000 scale). This study is based on the realization of a landslides inventory map and statistical data analysis using probabilistic methods. The methodology applied in ranking slope instability proceeded step by step. At first, geomorphologic investigation was performed in order to realize a landslide inventory map. A GIS database was created to collect the characteristics related to landslides geometry, type of movement and state of activity. Geo-engineering survey and characterization with in situ and laboratory tests allowed assessing Rock Mass Classification and geotechnical properties of soils (texture and consistency). The statistical approach for evaluating the landslide susceptibility is based on the assumption that the landslide probability for the currently landslides-free areas could be evaluated studying the conditions which led to past and present instability. A set of environmental factors, thought to be related to landslides, were analysed and their spatial distribution organized in different layers. Then, GIS-supported spatial analysis, conditional and multivariate analysis, allowed to calculate the connections between instability factors and landslide distribution. This step evolved towards two distinct statistical methods, both indirect and quantitative, leading to a classification of the land surface in some different susceptibility domains. Conditional analysis was applied to a particular type of terrain unit named Unique Condition Unit (UCU) that is a unique combination of the instability factors. The computer-aided evaluation of the landslide index within each UCU represents the probability of landslide occurrence, according to Bayes statistical concept. Multivariate analysis was applied to the same set of instability factors, but to a different type of terrain unit, the grid cell. The results showed a quantitative response, more reliable about the effectiveness of each instability factors, with the possibility of verifying their statistical significance. [Copyright &y& Elsevier]

We combined data from geomorphologic surveys, glacial modelling, and 10Be exposure ages of boulders on moraines, to investigate the Last Glacial Maximum (LGM) and the early retreat glacial phases in the Stura Valley of the Maritime Alps. We used the exposure ages to reconstruct the timing of standstills or readvances which interrupted the post-LGM withdrawal, initiated ∼24 ka. We mapped and dated the frontal moraines of a first glacial standstill/readvance at a short distance (∼7 km) from the maximum external limit of the LGM, which occurred at ∼22 ka, and a second one at ∼19 ka (Bühl stadial). This morpho-chronologic succession is congruent with that obtained in the adjacent Gesso Valley and, combined with the similarity of Equilibrium Line Altitude values, demonstrates a consistent glacial response in the Maritime Alps to climatic forcing. Our data are chronologically consistent with those of the southern flank of the European Alps, stressing not only a general synchroneity of the LGM across the various sectors, but also that of a LGM recessional standstill or readvance at ∼22 ka. The short distance between the LGM moraines and the recessionary phase moraines, and minimal difference in ELA indicate a modest variation in the mass balance of the Maritime Alps glaciers during this time interval. A similar modest variation between LGM and the first recessional phase glacier mass balance is also found throughout the western sector of the Southern Alps but is considerably more pronounced for the glaciers of the central-eastern sectors. This behaviour can be explained by the interplay between the moisture supplied by southern currents sourced in the Western Mediterranean and that advected by the westerlies sourced in the North Atlantic, which affected the various sectors of the Southern Alps differently. • New LGM and early deglaciation dated in the Maritime Alps (southwestern Alps). • Modest glacial mass balance change between the LGM and post-LGM early stadials. • Maritime Alps climate was wetter than the central-eastern southern Alps. [ABSTRACT FROM AUTHOR]

Abstract: Along the rock coasts of the Gulf of La Spezia, which are characterised by a Mediterranean microtidal environment, a limited number of small rock platforms are scattered, constrained in elevation within 5m above present-day sea level. This work deals with a number of these rock platforms, formed in different rock types (one in limestone and two in dolomite), that show differences in their morphology. This paper aims to provide a quantitative examination of why there are morphological differences between platforms in this region. To achieve this purpose, factors controlling platform morphology and the processes acting on them are investigated through a comparative analysis of rock strength. Rebound values, obtained testing rock surfaces with the Schmidt hammer, were compared between different platforms and between different sectors of the same platform. Each platform was subdivided into two parts based on visual difference in rock surface colour, characterised by differences in occurrence of weathering microforms and bioerosive agents. Rebound values in the lower part of the platforms proved to be lower than in the upper part, providing quantitative assessment of the occurrence of weathering acting to different extents in the upper and lower part of the shore platforms (weathering degraded rock strength in the lower part by about 15%). It was demonstrated that on the upper part of platforms, displaying moderate evidence of physical and biological weathering, lithology significantly influences the rock strength. On the portion of platforms closer to sea level, instead, differential exposure histories of the same rock type in the same environmental setting can yield statistically significant variations in rock strength values. Thus, it is clear that in the lower part of the investigated platforms, the degree of weathering has strong bearing on rock strength, and that variations in rock strength are not solely due to lithology. According to the results of this work, experimental values of rock strength of platforms in the study area depend both on the rock type and on physical weathering due to frequently repeated wetting and drying and bioerosion. Lithology is then an important factor controlling platform shape and weathering is an important process operating on them. [Copyright &y& Elsevier]