Giovanni Bertolini

Radiocarbon Data on Lateglacial and Holocene Landslides in the Northern Apennines

The Emilia Romagna slope of the Northern Apennines is strewnwith over 32,000 landslides, 5,000 of which are larger than 1 million cubic metres. They representthe remains of geomorphic agents that shaped the Apennines during the Holocene. Dating themby means of radiocarbon methods adds a contribution to the knowledge about the last periodof the geological geomorphological history of the Apennines. They can also be used to examinethe influence of Quaternary climatic changes on the instability of slopes and, for practicalor planning functions, to assess the periodicity of activity phases of the landslides. Thedating has been carried out on wood remnants buried under the landslide bodies. In some cases theentire tree trunk was found.In this paper we present radiocarbon dating of 20 casestudies in the Northern Apennines. Results range approximately from 13790–13670 cal y BP to950–790 cal`y BP. The oldest case is that of the Morsiano earth-flow, while the younger datedevent is represented by the Marano case that represents an example of how radiometric analysescan further enhance the available historical data. In the Cavola case, wood remnants of different ageswere found at different depths (from 9 to 45 m), allowing the dating of the first and followingperiods of activity of the landslide. The results are discussed and some considerations on the correlationbetween landslide occurrence and Holocene climate changes are proposed.

Fingerprints of Large-Scale Landslides in the Landscape of the Emilia Apennines

Impressive depletion and accumulation landforms created by the millennial evolution of large-scale landslides are distinctive features of the landscape of the Emilia Apennines (Northern Italy). They are complex earth slides and earth flows that can be tens of hectares wide and can involve millions of cubic metres of clayey deposits originated by the failure and weathering of weak rocks such as clayey flysch and melanges. These landslides have originated in large number since the upper Pleistocene. It is estimated that they now cover up to 20% of the mountain areas of the region. They typically alternate periods of dormancy that can be centuries long, to periods of reactivation that can last for a single season or several years. Upon reactivation, they rejuvenate landforms that outstand impressively from the surrounding landscape and cause severe damages to infrastructures. The chapter presents some relevant examples of these landslides and related hazard and risk issues.

A portable continuous GPS array used as rapid deployment monitoring system during landslide emergencies in Emilia Romagna

The possibility to rapidly deploy a continuous monitoring system in and around an active landslide during an emergency is crucial in order to gather information for hazard and risk scenarios updates. This paper deals with the use of an optimized portable and self-powered array of continuous GPS receivers that has been used for rapid deployment in several landslides during 2013 and 2014 emergency events in Emilia Romagna. In order to optimize the array of GPS receivers, so to make it a sort of plug-and-play system that can be operative in a few hours only and provide data in near-real time,, several technical and logistic issues had to be pre-evaluated and solved in the configuration of the system. These issues are illustrated in the short note together with some of the results obtained in the monitored sites.

Integration of ground-based interferometry and terrestrial laser scanning for rockslide and rockfall monitoring

A rockslide in Central Italy has been monitored by means of a ground-based interferometric radar and a terrestrial laser scanner in order to monitor its displacements and to provide both an early warning system and a feedback for the restoration works. The radar furnished near real time displacement maps that were integrated with 3D models of the slope reconstructed through the laser scanner. The integration between the two techniques permitted to reconstruct a high resolution 3D displacement maps of the rockslide also in the areas where profiling works created disturbance to radar data. As a support to the safety of workers and the durability of structural interventions, several detachment areas of rockfalls were also identified and the volume of the blocks calculated.