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Landslide databases are essential tools for risk assessment. In the Italian portion of the South-Eastern Alps these archives are managed by the Veneto Region and by the provinces of Bolzano and Trento, as part of the Italian Inventory of Landslides. About 750 rockfall events recorded in these archives were checked, put together and completed to create a new integrated database. Information on 24 new rockfalls were added from different research sources. Descriptive statistic shows that the most affected slopes with the highest frequency of rockfall are the southern ones. The distribution of rockfalls during the year presents three peaks in March, June and November. The most commonly affected lithologies are massive dolomites, effusive rocks and mica schists. Roads proved to be the most commonly involved feature. The hypsographic curves obtained from the DEMs of the provinces of Belluno, Bolzano and Trento have shown that the different areas potentially affected by periglacial processes experience rockfalls during summer and autumn, thus representing a risk to tourists and hikers. This study is the first attempt to collate and extend the available information in the various rockfall databases in the Eastern Italian Alps, with the aim at creating uniform data collection for the whole Alpine range. [ABSTRACT FROM AUTHOR]

On October 12th, 2007 about 40,000 m of dolomitic rock detached from the northern wall of the peak known as 'Cima Una' (Val Fiscalina, Sesto Dolomites, Bolzano, Italy), and fell 900 m to Fiscalina Valley below. The event generated a dense dust cloud, which traveled up to 4 km from the source area. The failure surface was formed by two near-vertical surfaces, almost perpendicular to each other. The orientation of these surfaces is consistent with two of the main regional tectonic sets. Only a small portion of the fallen material appeared to be preserved as blocks deposited at the base of the rock wall. About a fifth of the fallen mass was deposited on a colluvial cone. The missing mass, estimated to be about 80 %, may be represented by highly fragmented rock in part deposited as sand on the valley floor and in part dispersed as a dense dust cloud generated during the rockfall. There appears to be a deficit of deposited material, which could lead underestimation in the calculation of rock-cliff recession rates. The dynamics of the rockfall, strongly conditioned by the local topography, partially explains the intense rock breakage and the generation of the dust cloud. The rockfall was not caused by an external trigger, such as an earthquake or heavy rainfall; the failure was most likely progressive due to mechanical and physical degradation along highly stressed failure surfaces, possibly promoted by permafrost degradation and freeze and thaw processes. [ABSTRACT FROM AUTHOR]