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Alessandro CORSINI

Professore Associato presso: Dipartimento di Scienze Chimiche e Geologiche - Sede Dipartimento di Scienze Chimiche e Geologiche

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2020 - Contribution of water geochemistry and isotopes (δ18O, δ2H, 3H, 87Sr/86Sr and δ11B) to the study of groundwater flow properties and underlying bedrock structures of a deep landslide [Articolo su rivista]
Deiana, M.; Mussi, M.; Pennisi, M.; Boccolari, M.; Corsini, A.; Ronchetti, F.

A comprehensive understanding of bedrock lithology and groundwater circulation is necessary to identify areas prone to landslide initiation and reactivation. This necessity is particularly required in the case of outcroppings of weak rocks such as gypsum that, due to their high solubility and low mechanical strength, can promote slope deformation with the development of caves and collapses. In the Upper Secchia River Valley, where gypsum outcrops extensively and is covered by landslide deposits, an accurate identification of the gypsum outcrops and their distribution is needed to reduce the damage to urbanized slopes. In this paper, a hydrologic and geochemical approach is used in the Montecagno landslide to identify the origin, flow paths and transit time of groundwater circulating inside the landslide body and to identify gypsum deposits and their distribution in the bedrock. The results of groundwater-level monitoring, δ18O-δ2H and 3H isotope analyses and FLOWPC modelling suggest a local and recent origin of the groundwater hosted in shallow flow paths inside the landslide. Chemical and isotope (87Sr/86Sr, δ11B) analyses offer evidence of the presence inside the landslide of small blocks of gypsum that, due to their dimensions, probably have a minor influence on landslide stability. This research demonstrates that the methodology used can provide satisfactory information about bedrock structures and their hydrological aspects.

2020 - Correction to: Sinusoidal wave fit indexing of irreversible displacements for crackmeters monitoring of rockfall areas: test at Pietra di Bismantova (Northern Apennines, Italy) (Landslides, (2020), 17, 1, (231-240), 10.1007/s10346-019-01248-x) [Articolo su rivista]
Mulas, M.; Marnas, M.; Ciccarese, G.; Corsini, A.

The published version of this article, unfortunately, contained error. The corresponding author found out that in the published version, Figure 1c lacks the level regarding the crack meters position and labeling that was asked to edit during the proofreading.

2020 - Debris flows rainfall thresholds in the Apennines of Emilia-Romagna (Italy) derived by the analysis of recent severe rainstorms events and regional meteorological data [Articolo su rivista]
Ciccarese, G.; Mulas, M.; Alberoni, P. P.; Truffelli, G.; Corsini, A.

Recent severe rainstorms events in October 2014 and September 2015 triggered more than a hundred debris-flows in the western part of the Apennines of Emilia-Romagna (Italy). In this work, we tested a novel method to define debris flows rainfall thresholds for the 2014 and 2015 rainstorms (which have been used as reference events) and to extend these results across the Apennines of Emilia-Romagna, making use of long-term rainfall data of the regional raingauges network. Results are compared, for validation, to rainfall rates recoded during other past rainstorm-debris flows events (which have been used as validation events). At first, the method involves a spatial discriminant analysis between the spatial distribution of debris flows and the high frequency weather-radar rainfall data for the 2014 and 2015 reference events. The analysis defines rainfall cutoff values over rainfall durations from 30′ to 6 h, related to verification indices in the ROC curves, which are used as debris flows rainfall thresholds. Exceedance ratios are calculated between the computed rainfall thresholds and the rainfall rates at 10 years return periods at corresponding rainfall durations computed for raingauges located in the areas affected by the 2014 and 2015 events. The ratios are then used as multipliers of the rainfall rates at 10 years return periods over rainfall durations from 30′ to 6 h calculated for all other raingauges in the regional study area. To spatialize thresholds calculation to the regional scale, the computed thresholds are interpolated across the Apennines of Emilia-Romagna. The research resulted in the assessment of two-levels debris flows rainfall thresholds curves which seem to be adequate to discriminate rainfall rates recorded during past debris flows events used for validation. Discussion evidences advantages and limits of our approach, compares results to existing debris flows thresholds and highlights their possible use in a multi-stage warning procedure at regional scale.

2020 - Displacements of an Active Moderately Rapid Landslide—A Dataset Retrieved by Continuous GNSS Arrays [Articolo su rivista]
Mulas, Marco; Ciccarese, Giuseppe; Truffelli, Giovanni; Corsini, Alessandro

2020 - Integration of Digital Image Correlation of Sentinel-2 Data and Continuous GNSS for Long-Term Slope Movements Monitoring in Moderately Rapid Landslides [Articolo su rivista]
Mulas, Marco; Ciccarese, Giuseppe; Truffelli, Giovanni; Corsini, Alessandro

2020 - Redundancy and coherence of multi-method displacement monitoring data as key issues for the analysis of extremely slow landslides (Isarco valley, Eastern Alps, Italy) [Articolo su rivista]
Simeoni, Lucia; Ronchetti, Francesco; Costa, Carlo; Joris, Paolo; Corsini, Alessandro

The paper describes the study of two extremely slow, active-continuous, deep-seated landslides located in the Isarco Valley (Eastern Alps, Italy): a Multiple Rotational Rock Slide (MRRS) and partial reactivation of a Deep-Seated Gravitational Slope Deformation (DSGSD). Both landslides interact with viaducts on the E45 highway. Extensive multi-method field investigation, monitoring of surface and subsurface displacements and limit equilibrium stability analyses were adopted to fully characterize slope dynamics. In order to overcome the limitations due to the systematic errors affecting each single monitoring system and analysis method, an operative framework based on redundancy and coherence tests was introduced to check the reliability of the data and results. In this framework, the geological and geotechnical models of the investigated slopes were progressively refined. This allowed assessment of the type of interaction between the slopes and the highway viaducts.

2020 - Sinusoidal wave fit indexing of irreversible displacements for crackmeters monitoring of rockfall areas: test at Pietra di Bismantova (Northern Apennines, Italy) [Articolo su rivista]
Mulas, M.; Marnas, M.; Ciccarese, G.; Corsini, A.

Temperature changes affect crackmeters monitoring on a daily and a seasonal basis. This is due to rock mass thermal dilatancy and to instrumental matters. The consequent widening closing cycles can mask small irreversible displacements that might be precursors of rock failures. Recently, Weber et al. (Cryosphere 11:567–583, 2017) have proposed a linear fit method between temperature and fracture opening in order to compute the irreversibility index as a metrics to rank irreversible displacements. However, such an approach requires temperature sensors coupled to crackmeters. In order to overcome these limits, we propose an alternative method for deriving a normalised Z-score irreversibility index. It is based on sinusoidal wave fit of cracks opening time series only; thus, it does not require temperature monitoring. The methodology has been tested using data recorded by a wireless sensor network installed at La Pietra di Bismantova rock slab composed of 14 crackmeters and thermometers monitoring potentially unstable rock masses. A comparison of results obtained using the method of Weber et al. (Cryosphere 11:567–583, 2017) and the sinusoidal approach shows that the latter is much less sensitive to the duration of the moving window used to derive the irreversibility index, making it a much more flexible tool for indexing irreversible displacements over short time periods. Moreover, as rapid high–magnitude temperature changes can also be the causal factor of irreversible displacements, their statistical relation with peaks of the Z-score irreversibility index has been investigated. Results have shown that, depending on which crack is examined, correlations between irreversibility peaks and antecedent extreme temperature variations are more or less relevant. In conclusion, we believe that the Z-score sinusoidal wave fit irreversibility index (ZSFI) can represent a useful metrics for indexing irreversible displacements in unstable blocks using crackmeters’ datasets affected by temperature cycles at the daily and seasonal scale. [Figure not available: see fulltext.].

2020 - Tracer test to assess flow and transport parameters of an earth slide: The Montecagno landslide case study (Italy) [Articolo su rivista]
Ronchetti, Francesco; Piccinini, Leonardo; Deiana, Manuela; Ciccarese, Giuseppe; Vincenzi, Valentina; Aguzzoli, Alessandro; Malavasi, Gianluca; Fabbri, Paolo; Corsini, Alessandro

Subsurface water processes are principle triggering and driving factors during slope movements. However, thehydraulic properties that drive groundwaterflow along the slope remain poorly understood. Moreover, landslidedeposits are often characterized by layering andfissures that cause high heterogeneity in the distribution ofhydraulic properties. This heterogeneity leads to great uncertainty in the prediction of groundwaterflow paths.This study aimed to improve understanding of hydraulic and transport properties of deep earth slides and toidentify preferentialflow directions inside the landslide body. A dye tracer test was used to estimate transportparameters and characterize groundwaterflow paths. The results indicate that in the studied landslide, twogroundwaterflow types exist and are related to the presence offissured rock blocks and debris horizons em-bedded in afine matrix. The estimated low groundwaterflow velocity has rarely been estimated in other studiesof this landslide type. The groundwaterflow direction appears to be mainly influenced by the failure surfaceshape and differs from the sliding direction. Our results differ from those in other landslide studies and improveour knowledge of groundwaterflow properties in deep earth slides; furthermore, they offer a new contribution toslope stability analyses and formula, and to the effective design of mitigation strategies.

2019 - Mountain landslides: Monitoring, modeling, and mitigation [Articolo su rivista]
Corsini, A.; Borgatti, L.

This editorial paper summarizes the contents of the papers included in the Special Issue "Mountain Landslides: Monitoring, Modeling, and Mitigation". The Special Issue provides an overview of methodological papers, as well as some innovative research carried out in the field and in the lab. Even if most papers adopted an integrated approach, sections representing the three research issues outlined in the title can be drawn: the first deals with monitoring, the second focuses on modeling, and the third is related to mitigation. Regardless of the section, the papers included in this special issue put forward methodological and practical implications that, more than likely, can stimulate further research efforts and support the stakeholders to gain better knowledge of landslide hazards in mountain environments, with an aim to tackle the urgent issue of sustainable development in times of global change that can affect landslide occurrences in mountain chains of the world.

2019 - New isotopic surveys on the Poiano karst system [Abstract in Atti di Convegno]
Ronchetti, Francesco; Critelli, Vincenzo; Deiana, Manuela; Corsini, Alessandro; Lugli, Stefano; Mussi, Mario; Ercolani, Massimo; Curotti, Alessandra

2019 - Unusual becoming Usual: recent persistent-rainstorm events and their implications for debris flow risk management in the northern Apennines of Italy [Relazione in Atti di Convegno]
Corsini, Alessandro; Ciccarese, Giuseppe; Truffelli, Giovanni

The alluvial events of Parma (13 October 2014) and Piacenza (13-14 September 2015) in the northern Apennines of Italy have had significant effects in terms of flooding and morphological changes along the main and secondary rivers of the affected areas. The paper presents a summary of the characteristics of the rainstorm events, as well as of the triggered debris flows and their consequences on infrastructures. In the perspective of an extremization of rainfall regimes as a consequence of ongoing climate changes, these phenomena might become quite usual in the future and should be further studied in order to define regional-specific triggering thresholds, analyse precursors from weather radar datasets and assess susceptibility on a regional scale basis.

2018 - A comparison between bivariate and multivariate methods to assess susceptibility to liquefaction-related coseismic surface effects in the Po Plain (Northern Italy) [Articolo su rivista]
Lanfredi Sofia, C.; Oliveira, S. C.; Pereira, S.; Zêzere, J. L.; Corsini, A.

ABSTRACTThe two main events occurred during the 2012 seismic sequence on the Po Plain in Northern Italy (May 20 Mw 5.9 and May 29 Mw 5.8) induced widespread coseismic surface effects (CSEs), mostly liquefaction phenomena, which caused severe damages. To prevent risks related to CSE, an important non-structural measure is to assess locations susceptible to liquefaction, which is usually done at site scale by means of deterministic approaches in micro-zonation studies. This paper brings a novel methodological contribution in the field of CSE susceptibility mapping at regional scale, by testing and comparing bivariate (Weights of Evidence) and multivariate (Logistic Regression) methods that, so far, have not yet been used for such purpose. In a study area of 1480 km², the computation used an inventory of CSE as supporting evidence and a set of maps with geologic, geomorphic, hydrogeological and topographic factors as causal variables. Both methods provided susceptibility maps with a significant predictive capability and a fairly good spatial agreement between each other. In conclusion, this application of data-driven spatial modelling approaches indicates that such methods can be effectively used for liquefaction susceptibility zonation at regional scale, which can be of significant support for spatial planning over large areas.

2018 - Basin-scale analysis of the geomorphic effectiveness of flash floods: A study in the northern Apennines (Italy) [Articolo su rivista]
Scorpio, V.; Crema, Silvia; Marra, F.; Righini, M.; Ciccarese, G.; Borga, M.; Cavalli, M.; Corsini, A.; Marchi, L.; Surian, N.; Comiti, F.

Large floods may produce remarkable channel changes, which determine damages and casualties in inhabited areas. However, our knowledge of such processes remains poor, as is our capability to predict them. This study analyses the geomorphic response of the Nure River (northern Italy) and nine tributaries to a high-magnitude flood that occurred in September 2015. The adopted multi-disciplinary approach encompassed: (i) hydrological and hydraulic analysis; (ii) analysis of sediment delivery to the stream network by means of landslides mapping; (iii) assessment of morphological modifications of the channels, including both channel width and bed elevation changes. The spatial distribution of rainfall showed that the largest rainfall amounts occur in the upper portions of the catchment, with cumulative rainfall reaching 300 mm in 12 h, and recurrence intervals exceeding 100–150 years. The unit peak discharge ranged between 5.2 and 25 m3s−1km−2. Channel widening was the most evident effect. In the tributaries, the ratio between post-flood and pre-flood channel width averaged 3.3, with a maximum approaching 20. Widening was associated with channel aggradation up to 1.5 m and removal of riparian vegetation. New islands formed due to the fragmentation of the former floodplain. In the Nure River, the average width ratio was 1.7, and here widening occurred mainly at the expenses of islands. Bed level dynamics in the Nure were varied, including aggradation, incision, and overall stability. The flood geomorphic effectiveness was more pronounced in the middle-higher portions of the basin. Planimetric and elevation changes were well correlated. Regression analysis of the relationship between widening and morphological/ hydraulic controlling factors indicated that unit stream power and confinement index were the most relevant variables. The study provides useful insights for river management, especially with regard to the proportion of the valley floor subject to erosion and/or deposition during large events.

2018 - Chemical and isotopic investigations (δ18O, δ2H, 3H, 87Sr/86Sr) to define groundwater processes occurring in a deep-seated landslide in flysch [Articolo su rivista]
Deiana, Manuela; Cervi, F.; Pennisi, M.; Mussi, M.; Bertrand, C.; Tazioli, A.; Corsini, A.; Ronchetti, F.

Deep-seated landslides are complex systems. In many cases, multidisciplinary studies are necessary to unravel the key hydrological features that can influence their evolution in space and time. The deep-seated Berceto landslide, in the northern Apennines of Italy, has been investigated in order to define the origin and geochemical evolution of groundwater (GW), to identify the slope system hydrological boundary, and to highlight the GW flow paths, transit time and transfer modalities inside the landslide body. This research is based on a multidisciplinary approach that involves monitoring GW levels, obtaining analyses of water chemistry and stable and unstable isotopes (δ18O-δ2H, 3H, 87Sr/86Sr), performing soil leaching tests, geochemical modelling (PHREEQC), and principal component analysis (PCA). The results of δ18O-δ2 H and 87Sr/86Sr analyses show that the source of GW recharge in the Berceto landslide is local rainwater, and external contributions from a local stream can be excluded. In the landslide body, two GW hydrotypes (Ca-HCO3 and Na-HCO3) are identified, and the results of PHREEQC and PCA confirm that the chemical features of the GW depend on water–rock interaction processes occurring inside the landslide. The 3H content suggests a recent origin for GW and appears to highlight mixing between shallow and deep GW aliquots. The 3H content and GW levels data confirm that shallow GW is mainly controlled by a mass transfer mechanism. The 3H analyses with GW levels also indicate that only deep GW is controlled by a pressure transfer mechanism, and this mechanism is likely the main influence on the landslide kinematics.

2018 - Colate detritiche durante gli eventi alluvionali del 13 ottobre 2014 in provincia di Parma e 13-14 settembre 2015 in provincia di Piacenza [Articolo su rivista]
Ciccarese, G.; Truffelli, G.; Corsini, A.

2018 - Deformation responses of slow moving landslides to seasonal rainfall in the Northern Apennines, measured by InSAR [Articolo su rivista]
Bayer, Benedikt; Simoni, Alessandro; Mulas, Marco; Corsini, Alessandro; Schmidt, David

Slow moving landslides are widespread geomorphological features in the Northern Apennines of Italy where they represent one of the main landscape forming processes. The lithology of the Northern Apennines fold and thrust belt is characterized by alternations of sandstone, siltstone and clayshales, also known as flysch, and clay shales with a chaotic block in matrix fabric, which are often interpreted as tectonic or sedimentary mélanges. While flysch rocks with a high pelitic fraction host earthslides that occasionally evolve into flow like movements, earthflows are the dominant landslide type in chaotic clay shales. In the present work, we document the kinematic response to rainfall of landslides in these different lithologies using radar interferometry. The study area includes three river catchments in the Northern Apennines. Here, the Mediterranean climate is characterized by two wet seasons during autumn and spring respectively, separated by dry summers and winters with moderate precipitation. We use SAR imagery from the X-band satellite COSMO SkyMed and from the C-band satellite Sentinel 1 to retrieve spatial displacement measurements between 2009 and 2016 for 25 landslides in our area of interest. We also document detailed temporal and spatial deformation signals for eight representative landslides, although the InSAR derived deformation signal is only well constrained by our dataset during the years 2013 and 2015. In spring 2013, long enduring rainfalls struck the study area and numerous landslide reactivations were documented by the regional authorities. During 2013, we measured higher displacement rates on the landslides in pelitic flysch formations compared to the earthflows in the clay shales. Slower mean velocities were measured on most landslides during 2015. We analyse the temporal deformation signal of our eight representative landslides and compare the temporal response to precipitation. We show that earthslides in pelitic flysch formations accelerate faster than earthflows in chaotic clay shales and reach higher velocities, while the kinematic behaviour of the earthflows can be described as rather steady with only minor accelerations. Although we have no detailed pore pressure measurements for the period of interest, the observed behaviour can be explained in our view by the morphological and hydrological characteristics of the different landslide types. On the one hand landslide material and bedrock in the pelitic flysch rocks are more resistant, which is why slope angles are higher in this lithology. On the other hand, landslides in the pelitic flysch formations have often deeper slip surfaces and landslide material is more permeable. This is why long persistent rainfall is necessary to saturate the landslide material and induce pore pressures that are high enough to trigger displacement.

2018 - Rock stability as detected by seismic noise recordings - Three case studies [Relazione in Atti di Convegno]
Taruselli, M.; Arosio, D.; Longoni, L.; Papini, M.; Corsini, A.; Zanzi, L.

2018 - Slope dynamics and streambed uplift during the Pergalla landslide reactivation in March 2016 and discussion of concurrent causes (Northern Apennines, Italy) [Articolo su rivista]
Mulas, Marco; Ciccarese, Giuseppe; Ronchetti, Francesco; Truffelli, Giovanni; Corsini, Alessandro

On March 28, 2016, the toe zone of the apparently dormant Pergalla earthslide-earthflow (Northern Apennines, Italy) had a paroxysmal reactivation. In the course of 2 days, displacements up to almost 8 m severely damaged several houses and roads. At the bottom of the slope, the emersion of rotational sliding surfaces determined the uplift of almost 3 m of the Nure river streambed that was consequently partially dammed. The paper describes the landslide event on the basis of field surveys and analysis of post-event aerial photos, as well as data from geophysical surveys and pre- to post-failure displacement monitoring. It also discusses the possible concurrent causes of the event, including antecedent rainfall, the migration of active streambed channels of Nure river toward the landslide toe in the previous year, and the existence of long-term pre-failure slow movements. It is concluded that these factors, together with the presence of sliding surfaces extending beneath the valley floor, should be primarily considered if a preventive assessment of river damming potential due to streambed uplift should be made for other similar landslides in the Apennines.

Nistor, Mărgărit Mircea; Ronchetti, Francesco; Corsini, Alessandro; Cheval, Sorin; Dumitrescu, Alexandru; Kumar Rai, Praveen; Petrea, Dănuţ; Dezsi, Ştefan

The crop evapotranspiration computing is a complex matter from many points of view, but also it represents a useful parameter in hydrological and climate studies. Due to climate changes, the natural systems are coming to be negatively affected. The seasonal and annual crop evapotranspiration under current climate (1991-2020) and future climate (2021-2050) were analysed using the mean annual temperature, mean annual precipitation, and mean monthly potential evapotranspiration for average of 30 years. The spatial distribution of crop evapotranspiration was calculated considering the evapotranspiration coefficients taken from literature using four stages of crops growth. Additionally, the absolute and relative changes of the annual crop evapotranspiration were carried out. The annual crop evapotranspiration varies in the actual period from 56 mm to 1297 mm, while in the future period the annual crop evapotranspiration varies from 59 mm to 1410 mm, which implies the impact of future climate warming on the crop evapotranspiration in the South East Europe. The heights values were identified in the South of Greece, in the southwestern sides of Romania, in the East sides of Bulgaria, Croatia and European Turkey. The maximum seasonal crop evapotranspiration were found in the mid-season, both for present and future. The minimum values of seasonal crop evapotranspiration were obtained in the cold season, when the mean air temperature and crop coefficients are lower. The absolute and relative changes indicate the high values in the South and southwestern sides of the South East Europe.

Corsini, Alessandro; Ciccarese, Giuseppe; Diena, M.; Truffelli, G.; Alberoni, P. P.; Amorati, R.

During the 13 October 2014 rainstorm event that affected the Val Parma and Val Baganza area, several debris flows affected the Mt. Cervellino relief (northern Apennines, Italy), causing severe and widespread damages to check-dams, roads and other infrastructures. Such event, together with the Piacenza province event of 2015, has generated the perception of debris flows as a breaking new potential cause of widespread damages in the Emilia-Romagna. The meteorological event of October 2014, reconstructed by means of rain gauges and radar data, reached intensities as high as 80 mm/hour, which is well above any debris flow triggering thresholds presented in literature. However, data show that debris flows have occurred in any location where 30 mm/hour were exceeded. The result was the occurrence of tens of debris flows, which were triggered in zones of failure of slope debris coverage along the streams, and that remobilized and scoured debris along the track and destroyed several check dams and damaged roads that were overflown by debris. This paper is aimed to document the distribution and characteristics of the debris flow events that occurred during such event. By doing so, it also warns against this potentially destructive events that, in a changing meteorological framework, might result much more frequent and widespread than expected also in the northern Apennines.

2017 - Development of multi-purposes procedures and service tools for GNSS data processing finalized to monitor a deep-seated earthslide in the Dolomites (Italy) [Abstract in Atti di Convegno]
Crespi, Mattia; Fratarcangeli, Francesca; Mazzoni, Augusto; Nascetti, Andrea; Monsorno, Roberto; Schloegel, Romy; Corsini, Alessandro; Mulas, Marco; Mair, Volkmar

The Corvara landslide is an active, large-scale, deep-seated and slow moving earthslide of about 30 Mm3 located in the Dolomites (Italy). It is frequently damaging a national road and, occasionally, isolated buildings and recre- ational ski facilities. In this work we present the analysis performed on data acquired thank to the installation of 3 DualFrequency GPS in permanent acquisition installed in the accumulation, track and source zone of the active portion of the landslide. In particular two years (2014 and 2015) of data were processed with several approaches and goals: daily time series were produced through Precise Point Positioning and Differential Positioning using both scientific packages and automatic on line tool based on open source libraries, specifically developed in order to provide a prototypal service. The achievable results based on single frequency (L1) data processing were also investigated in order to pave the way to the deployment of lowcost GPS receiver for this kind of application. Moreover, daily and sub-daily phenomena were analyzed. Different strategies were investigated in order to de- scribe the kinematics on the basis of 0.2 Hz data collected by the 3 permanent receivers. For particular events also the variometric approach, through the recent advances of VADASE, was applied, to detect significant movements. Finally, tropospheric parameters were estimated over the whole period in order to give a contribution to the SAR interferometry techniques. Also for this specific purpose and application, the possibilities of single frequency use were assessed.

2017 - Fingerprints of Large-Scale Landslides in the Landscape of the Emilia Apennines [Capitolo/Saggio]
Bertolini, G.; Corsini, Alessandro; Tellini, C.

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 mélanges. 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.

2017 - Groundwater Flow Characterization Using Different Hydraulic Methods in Large and Deep Earth-Slide Rich in Clay [Relazione in Atti di Convegno]
Ronchetti, Francesco; Piccinini, Leonardo; Deiana, Manuela; Fabbri, Paolo; Corsini, Alessandro

Since 2013, different hydraulic tests have been conducted and replicated in a large earth slide characterized by a landslide body that is rich in clay, has a mean thickness of 30 meters, and is located in the Northern Apennines, Italy. All the tests were performed to estimate the hydrogeological properties of the landslide and to design future mitigation measures. To define the geometry of the sliding mass, the stratigraphy in more than 15 boreholes was analyzed. The boreholes were subsequently equipped with inclinometers and open standpipe piezometers. According to the stratigraphy, the landslide body is characterized by the presence of gravel layers in a clay-rich matrix. This study compares the results from the different techniques applied to 2 boreholes, 5 open standpipe piezometers and 1 well. The number of tests performed for each test type were 31 slug tests (ST), 4 falling head tests (FT), 5 low-flow pumping tests (PT), 1 point dilution (PD) test, and 2 aquifer tests (AT). Moreover, the test data was evaluated with different solutions. The ST data was evaluated with the Hvorslev and KGS solutions; the FT data was evaluated with the AGI and Hvorslev solutions; the PT data was evaluated with the Muskat solutions; the AT data was evaluated with the Theis, Cooper-Jacob, Neuman, Moench and Tartakosky-Neuman solutions; and the PD test data was evaluated with the classical solution where Darcy velocity is calculated as a function of the rate of dilution. The results show that hydraulic conductivity (K), storage (S) and specific storage (Ss) vary in the horizontal plane and with the depth (K ranges between 1.0E-5 and 1.0E-8 m/s; S ranges between 4.0E-3 and 5E-5; and Ss ranges between 1.0E-3 and 3.0E-3 1/m). The horizontal and vertical variability is correlated with the lithologic heterogeneity highlighted by the borehole stratigraphy. Moreover, all the hydraulic tests conducted on the landslide body give highly consistent results. Comparison of results derived from different methods show that they are comparable with each other and they differ by one order of magnitude only in a few cases.

2017 - Landslide Zoning Using the Principal Component Analysis on Monitoring Data: The Sauna Earth Slide—Earth Flow (Parma, Italy) [Relazione in Atti di Convegno]
Mulas, Marco; Bonacini, Francesco; Petitta, Marcello; Ronchetti, Francesco; Truffelli, Giovanni; Diena, Michela; Corsini, Alessandro

In this contribute, we present the morphodynamic zoning of the Sauna complex earth slide—earth flow (Corniglio municipality, Northern Apennines) obtained by integrating results of field surveys and of Principal Component Analysis (PCA) of continuous displacement monitoring data. Since January 2014, the area is surveyed by an Automated Total Station (ATS) monitoring 30 prisms with duty cycles of 2 h. An evacuation plan has been adopted by the local authorities, which is based on pre-defined movement thresholds. However, during more than 2 years of monitoring, the results have evidenced that in different zones of the slope, differentiate displacement rates and timings of response to precipitations take place. Therefore, in order to fine tune evacuation plans, movement thresholds should be more appropriately tailored on the basis of morphodynamic zones rather than being left spatially generic. The final result is a morphodynamic zonation of the slope that represents a useful document to identify areas in which differentiated movement thresholds can be assessed for alert and alarm.

2017 - Monitoring the rapid-moving reactivation of earth flows by means of GB-InSAR: The April 2013 Capriglio Landslide (Northern Appennines, Italy) [Articolo su rivista]
Bardi, Federica; Raspini, Federico; Frodella, William; Lombardi, Luca; Nocentini, Massimiliano; Gigli, Giovanni; Morelli, Stefano; Corsini, Alessandro; Casagli, Nicola

This paper presents the main results of the GB-InSAR (ground based interferometric synthetic aperture radar) monitoring of the Capriglio landslide (Northern Apennines, Emilia Romagna Region, Italy), activated on 6 April 2013. The landslide, triggered by prolonged rainfall, is constituted by two main adjacent enlarging bodies with a roto-translational kinematics. They activated in sequence and subsequently joined into a large earth flow, channelizing downstream of the Bardea Creek, for a total length of about 3600 m. The displacement rate of this combined mass was quite high, so that the landslide toe evolved with velocities of several tens of meters per day (with peaks of 70-80 m/day) in the first month, and of several meters per day (with peaks of 13-14 m/day) from early May to mid-July 2013. In the crown area, the landslide completely destroyed a 450 m sector of provincial roadway S.P. 101, and its retrogression tendency exposed the villages of Capriglio and Pianestolla, located in the upper watershed area of the Bardea Creek, to great danger. Furthermore, the advancing toe seriously threatened the Antria bridge, representing the "Massese" provincial roadway S.P. 665R transect over the Bardea Creek, the only strategic roadway left able to connect the above-mentioned villages. With the final aim of supporting local authorities in the hazard assessment and risk management during the emergency phase, on 4 May 2013 aerial optical surveys were conducted to accurately map the landslide extension and evolution. Moreover, a GB-InSAR monitoring campaign was started in order to assess displacements of the whole landslide area. The versatility and flexibility of the GB-InSAR sensors allowed acquiring data with two different configurations, designed and set up to continuously retrieve information on the landslide movement rates (both in its upper slow-moving sectors and in its fast-moving toe). The first acquisition mode revealed that the Capriglio and Pianestolla villages were affected by minor displacements (at an order of magnitude of a few millimeters per month). The second acquisition mode allowed to acquire data every 28 seconds, reaching very high temporal resolution values by applying the GB-InSAR technique.

2017 - Multi-Temporal X-Band Radar Interferometry Using Corner Reflectors: Application and Validation at the Corvara Landslide (Dolomites, Italy) [Articolo su rivista]
Schlögel, Romy; Thiebes, Benni; Mulas, Marco; Cuozzo, Giovanni; Notarnicola, Claudia; Schneiderbauer, Stefan; Crespi, Mattia; Mazzoni, Augusto; Mair, Volkmar; Corsini, Alessandro

From the wide range of methods available to landslide researchers and practitioners for monitoring ground displacements, remote sensing techniques have increased in popularity. Radar interferometry methods with their ability to record movements in the order of millimeters have been more frequently applied in recent years. Multi-temporal interferometry can assist in monitoring landslides on the regional and slope scale and thereby assist in assessing related hazards and risks. Our study focuses on the Corvara landslides in the Italian Alps, a complex earthflow with spatially varying displacement patterns. We used radar imagery provided by the COSMO-SkyMed constellation and carried out a validation of the derived time-series data with differential GPS data. Movement rates were assessed using the Permanent Scatterers based Multi-Temporal Interferometry applied to 16 artificial Corner Reflectors installed on the source, track and accumulation zones of the landslide. The overall movement trends were well covered by Permanent Scatterers based Multi-Temporal Interferometry, however, fast acceleration phases and movements along the satellite track could not be assessed with adequate accuracy due to intrinsic limitations of the technique. Overall, despite the intrinsic limitations, Multi-Temporal Interferometry proved to be a promising method to monitor landslides characterized by a linear and relatively slow movement rates.

2017 - Perennial springs provide information to predict low flows in mountain basins [Articolo su rivista]
Cervi, F.; Bloschl, G.; Corsini, A.; Borgatti, L.; Montanari, A.

A new method for estimating low flows in ungauged rivers from minimum discharge of perennial springs is proposed. This spring-based approach (SBA) is tested in 21 catchments from the northern Apennines, Italy. First, the hydrogeological behaviour of each geological formation and superficial deposit is related to the spatial distribution and discharge of perennial springs in a test area using a Bayesian approach, weight of evidence (WoE). Second, the observed river flow exceeded for 95% of the observation period is related to the type of geological formations outcropping within the catchment. Finally, the q95 low flows are estimated from the WoE weights. The SBA performance is assessed by leave-one-out cross-validation and compared with the results of a multiple regression (MR) model that accounts for selected catchment characteristics, but no springs. The results show that the SBA outperforms MR. The better performance of the SBA may be related to its ability to capture bedrock characteristics, which are the main controls of low flows in the study area.

2017 - Remote Sensing Mapping and Monitoring of the Capriglio Landslide (Parma Province, Northern Italy) [Relazione in Atti di Convegno]
Bardi, Federica; Raspini, Federico; Frodella, William; Lombardi, Luca; Nocentini, Massimiliano; Gigli, Giovanni; Morelli, Stefano; Corsini, Alessandro; Casagli, Nicola

In the spring of 2013, the Parma Province (Northern Italy) was affected by a large number of landslides, as a result of heavy and persistent rainfall occurred between January and April. This resulted in the triggering of about 1400 mapped landslides, which caused severe damages. In particular, on April 6th 2013, a large landslide activated in Tizzano Val Parma municipality. It stretches from an altitude of 980 m to about 630 m a.s.l., covering an area of 0.92 km(2) with a total length of 3600 m. It is constituted by two main adjacent enlarging bodies with a roto-translational kinematics, channelizing downstream the Bardea Creek, forming an earth flow. The landslide crown area destroyed a 450 m-long sector of a provincial roadway, and its retrogression tendency put at risk the Capriglio and Pianestolla villages, located in the upper watershed area of the Bardea river. Moreover, the advancing toe threatened the Antria bridge, representing the "Massese" provincial roadway transect over the Bardea Creek. This work describes the main results of the landslide mapping and monitoring activities, conducted after the landslide trigger. With the aim of supporting local authorities in the hazard assessment and risk management, an integrated analysis of various remote sensing data was developed, in order to generate a multi-temporal mapping of the landslide, whose velocity reached values of several tens of meters per day in the first month, and several meters per day from early May to mid-July 2013. Satellite and aerial post-event images were analyzed, together with the results of field surveys, to accurately map the landslide extension and evolution. Moreover, on May 2013, a GB-InSAR (Ground Based Interferometric Synthetic Aperture Radar) monitoring campaign was started in order to assess displacements of the whole landslide area and to support early warning activities. The GB-InSAR acquired until December 2013.

2017 - Seismic Noise Measurements on Unstable Rock Blocks: The Case of Bismantova Rock Cliff [Relazione in Atti di Convegno]
Arosio, Diego; Corsini, Alessandro; Giusti, Riccardo; Zanzi, Luigi

In this work, we tested the use of passive seismic for the characterization of potentially unstable rock blocks in the Pietra di Bismantova site, a wide slab of calcareous sandstone located in the Northern Apennines of Italy. Ambient vibrations recordings with broad-band 3-component seismometers were carried out on potentially unstable areas such as 5 rock blocks and 1 rock column located close to the top of the 100 m-high cliff. The rock blocks are also monitored by means of crackmeters. Seismic noise recordings were processed with a standard sequence and noise spectra and spectral ratios have been evaluated. Preliminary results are promising since in some cases a significant frequency peak can be observed, indicating resonance effects due to the vibration of the rock pillars. In addition, for the most favorable case, noise polarization analysis presents vibration direction values at given frequency in a limited angle range, reasonably corresponding to the direction of maximum displacement. Future investigations could address additional noise measurements and their correlation with the crackmeter datasets in order to understand possible relationship between change in resonance frequency or signal polarization and crackmeter hysteresis path. Moreover, new ambient noise surveys could be planned as a pilot investigation campaign, with the aim of designing extensometer monitoring network tuned on the most critical situations.

2017 - Use of ROC curves for early warning of landslide displacement rates in response to precipitation (Piagneto landslide, Northern Apennines, Italy) [Articolo su rivista]
Corsini, Alessandro; Mulas, Marco

Active landslides are generally characterized by variations in displacement rate in response to cumulated precipitation. Velocities that are only exceeded in a limited number of days during the year might be considered as critical events, since they might determine, or prelude to, a significant evolution of the landslide. The purpose of this paper is to present a novel approach based on the use of receiver operating characteristic (ROC) curves for assessing cumulated precipitation thresholds that can provide early warning for the occurrence of critical events such as the exceedance of rare displacement rates. The approach has been developed and tested in the Piagneto landslide, an active complex rock slide—debris slide in the Northern Apennines of Italy, for which a 5-year continuous surveying monitoring dataset is available. On the basis of the first 4 years of monitoring data (training dataset), threshold curves relating cumulative precipitation (mm) to precipitation moving windows (days) have been generated by using different benchmarks that, in literature, are used to estimate the maximum predictive performance of ROC curves. These threshold curves have been successfully validated using the last 1 year of monitoring data (validation dataset). They have then been used to simulate how they might help defining different early warning levels in due advance. The proposed methodology can be replicated in any landslide for which a monitoring dataset that includes recurrent acceleration events in response to precipitation is available.

2017 - Using Weather Radar Data (Rainfall and Lightning Flashes) for the Analysis of Debris Flows Occurrence in Emilia-Romagna Apennines (Italy) [Relazione in Atti di Convegno]
Ciccarese, Giuseppe; Corsini, Alessandro; Alberoni, Pier Paolo; Celano, Miria; Fornasiero, Anna

During the last years, the Emilia-Romagna Apennines have been severely affected by debris flows, a type of landslide that is relatively uncommon in this area. These phenomena occur as a result of intense rainfall. The two most significant events are the one that affected the Province of Parma in October 2014 and the one that affected the Province of Piacenza in September 2015, in the night between the 13th and 14th. The objective of this work is to identify relationships between rainfall and debris flows occurrence for the Piacenza 2015 event, through the analysis of the distribution of debris flows with respect to rainfall data from weather radar and rain gauges recorded by ARPAE. The analysis of the relationships between spatial occurrence of debris flows and rainfall peaks has been based on the definition of the % of debris flow triggering points that can be contoured inside isohyets and on the ROC curve method. Moreover, we analyzed possible correlations between rainfall intensity and density or number of lighting flashes. The rainfall intensity vs duration plot showed that the September 2015 event largely exceeded debris-flows triggering thresholds proposed in literature. Analysis of debris flows occurrence with respect to hourly precipitation peaks retrieved by weather radar data, evidenced that 100% of the debris flows points occurred above the 30 mm/h isohyet, 97%, above the 50 mm/h isohyet and 82.5% above the 60 mm/h isohyet. Using ROC curves, the spatial distribution of debris flows triggering points can be more precisely predicted by considering, rainfall peaks at 1 h and 30 min over the event or by considering hourly rainfall between 02:00 and 03:00 of 15/09/2015. Rainfall classes of the best cut-off points in these ROC curves, i.e. most significant classifiers of the location debris flows points, are 75–90 mm/1 h and 45–60 mm/30 min. The analysis of lightning data shows that rainfall intensity was directly correlated to the lightning density but, also, that in some sub-areas a better correlation is obtained by considering rainfall intensity versus the lightning density recorded in the previous 30 min

2016 - A wireless crackmeters network for the analysis of rock falls at the Pietra di Bismantova natural heritage site (Northern Apennines, Italy) [Relazione in Atti di Convegno]
Corsini, Alessandro; Bonacini, Francesco; Deiana, Manuela; Giusti, Riccardo; Russo, M. .; Ronchetti, Francesco; Cantini, C.; Truffelli, G.; Iasio, C.; Generali, M.; Ascari, L.; Chiesi, L. .; Venturi, L.

The Pietra di Bismantova (Northern Apennines, Italy) is a large calcareous sandstone rock slab which is distinctively bordered by sub-vertical cliffs that are affected by rock falls, a risk for people visiting the area and for key assets located at the foot of this natural heritage site. A wireless sensor network based on wireless nodes, crack meters and thermometers has been made operative in January 2015 in order to study the response of fractures to changing environmental conditions and support the spatial and temporal zonation of rock fall hazard in this natural heritage site. Results from the first eight months of monitoring show that intense snowfall and low temperatures can determine short-term pulses of fracture opening while the increase of temperature throughout summer determines long-term fracture closing trends. Moreover, as soon as February 2015 one of the crack meters monitored the rapid trend of crack opening that occurred prior to the failure of a large rock slab of about 200 cubic meters.

2016 - Assessment of the 2006 to 2015 Corvara landslide evolution using a UAV-derived DSM and orthophoto [Relazione in Atti di Convegno]
Thiebes, B; Tomelleri, E; Mejia Aguilar, A; Rabanser, M; Schlögel, R; Mulas, Marco; Corsini, Alessandro

We present a UAV-based photogrammetry study on Corvara landslide, a large and active earthflow in the Italian Dolomites. During a one-day field survey, an area of approximately 13 ha was cov- ered and a very high resolution orthophoto and a point cloud consisting of more than 200 million points were created. From this data, a Digital Surface Model (DSM) with a pixel size of 1.5 cm was prepared. The comparison to the existing 2006 LiDAR DSM highlights landslide enlargements, displacement rates and material depletion and accumulation exceeding 11 m. Although some uncertainties regarding the exact magnitude of topographical changes remain, the methodology has been evaluated as a useful addi- tion to the ongoing monitoring activities on the Corvara landslide by GPS and DInSAR due to the unprecedented level of detail.

2016 - Debris flows in Val Nure and Val Trebbia (N Apennines) during the September 2015 alluvial event in Piacenza Province (Italy) [Articolo su rivista]
Ciccarese, G.; Corsini, A.; Pizziolo, M.; Truffelli, G.

During September 2015, some municipalities of Val Nure and Val Trebbia areas (Piacenza province) have been affected by a severe rainstorm event which has caused flooding along rivers and debris flows and landslides on slopes. A toll of 3 casualties and serious damages to infrastructures and roads was paid. In the mostly affected areas, rainfall in 6 hours reached 298 mm with an hourly precipitation peak of 107,6 mm/h. In an area of approximately 500 km2, 103 debris flow have occurred. The distribution of debris flows seems to be controlled by the distribution of the intensity of the rainstorm. Debris flows seems to have in many cases caused by slope failures in the upper part of the sub-basins. These phenomena remobilized slope debris that, subsequently, was transported by channelized debris flows. Major damages were suffered at locations where roads are crossing the creeks and streams along which the debris flow occurred. A preliminary analysis of affected sub-basins in one of the areas mostly affected by debris flows, indicates that a straightforward discrimination of the susceptibility of sub-basins based on simple morphometric and lithologic factors is not possible.

2016 - Impulsive ground movements in the mud volcanoes area of "le Sarse" di Puianello (Northern Apennines, Modena, Italy): Field evidence and multi-approach monitoring [Articolo su rivista]
Mulas, Marco; Bayer, Benedikt; Bertolini, Giovanni; Bonacini, Francesco; Leuratti, Enrico; Pizziolo, Marco; Simoni, Alessandro; Corsini, Alessandro

In this contribution we present the work carried out to determine the nature of the impulsive vertical ground movements occurred in February 2015 in the mud-volcanoes area "Le Sarse" (Northern Apennines, Modena province, Italy). A multi-technique based work has been started including field surveys, SAR Multi-Interferometric processing and high-precision periodical D-GPS monitoring. Field evidence indicates that movements occurred in February 2015, in the order of 25 cm in few minutes, can be ascribed to a vertical collapse of part of the caldera area rather than to a landslide activity. The affected area is bordered by concentric normal faults that were originated during February 2015. According to SAR interferometry, the collapsed area was already undergoing movements in the order of 2 cm/year at least from 2012. The D-GPS monitoring indicates that movement rates have nowadays still taking place at rates higher than those of the pre-event. In conclusion, it can be assumed that movements in the area are most likely related to the mechanisms controlling the activity and evolution of the mud volcano itself. However, the reconstruction of the structural characteristics of this caldera system and the identification of the specific causes for the February 2015 event still need to be further investigated.

2016 - Monitoring landslide kinematics by multi-temporal radar interferometry - the Corvara landslide case study [Abstract in Atti di Convegno]
Thiebes, Benni; Cuozzo, Giovanni; Callegari, Mattia; Schlögel, Romy; Mulas, Marco; Corsini, Alessandro; Mair, Volkmar

2016 - Quantitative monitoring of surface movements on active landslides by multi-temporal, high-resolution X-Band SAR amplitude information: Preliminary results [Relazione in Atti di Convegno]
Mulas, Marco; Corsini, Alessandro; Cuozzo, G; Callegari, Mattia; Thiebes, Benjamin; Mair, V.

Multi-temporal image cross-correlation is a method for tracking moving features and can there-fore be used for quantitative assessments of surface displacements. Accuracies of up to 1/8th of the original image geometric resolution can be achieved. We present the results of an analysis car- ried out on Corvara landslide located in the Italian Dolomites. Image offset-tracking was applied to CosmoSky-Med amplitude images acquired between October 2013 and August 2015. The presence of a validation dataset consisting of periodical GPS surveys carried out on 16 benchmarks represents an ideal opportunity to test the applicability of SAR-based image cross-correlation for landslide moni- toring. Despite the relative low accuracy of the results amplitude-based offset-tracking proved to be beneficial due to the ability of this method to capture large displacements. In particular the results evidence its complementarity with respect to multi-temporal interferometry that is confined to slow displacements along E-W directions.

2016 - Toward a centralized data management center for integrated landslide monitoring in Emilia Romagna Region (Italy) [Relazione in Atti di Convegno]
Corsini, Alessandro; Bonacini, Francesco; Ciccarese, Giuseppe; Mulas, Marco; Ronchetti, Francesco; Nanni, Stefania; Truffelli, Giovani; Caputo, Giuseppe; Pizziolo, Marco; Primerano, Sabrina; Monni, Antonio

In Emilia Romagna Region, slope monitoring systems have become more widely used for hazard and risk management. However, they are generally non-interoperable. Moreover dispersion of monitoring data in several local databases have made data sharing among the involved institutional actors quite laborious and often untimely. A centralized database and a web-based portal that integrate infor- mation derived by different types of slope monitoring systems has been developed. The paper illustrates the specific features of the developed “SensorNet” and provides examples of its use for visualizing and analyzing in an integrated manner data from different monitoring systems. In perspective it could serve as an every-day operational tool for a timely reporting of landslide monitoring data for surveillance and warning purposes.

2015 - A portable continuous GPS array used as rapid deployment monitoring system during landslide emergencies in Emilia Romagna [Articolo su rivista]
Corsini, A.; Bonacini, F.; Mulas, M.; Ronchetti, F.; Monni, A.; Pignone, S.; Primerano, S.; Bertolini, G.; Caputo, G.; Truffelli, G.; Benini, A.; Berti, M.

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.

2015 - Acceleration of large active earthflows triggered by massive snow accumulation events : evidences from monitoring the Corvara landslide in early 2014 ( Dolomites , Italy ) [Abstract in Atti di Convegno]
Corsini, Alessandro; Mulas, Marco; Marcato, Gianluca; Chinellato, Giulia; Mair, Volkmar

In the Dolomites of Italy, snowfall during winter 2013/2014 was exceptionally abundant. Major snowfall events occurred from late December 2013 to mid-March 2014. Snow accumulation in Badia Valley peaked in early February: from 2 to 4 meters with a positive gradient respect to altimetry and accordingly to wind accumulation zones. Below 2000 m asl, due to the mild temperatures recorded before the onset of snowfall, the relatively dry snow cover was mostly deposited on top of unfrozen soils. The Corvara landslide is a large active earthflow located close to Corvara in Badia, at an elevation from 2000 to 1600 m. It’s displacement rate before, during and after the exceptional snowfall period was monitored at high temporal frequency. Surface displacement was measured bi-weekly by differential GPS in several benchmarks in the source, track and accumulation zone. Deep displacement was monitored semi-continuously by two in-place inclinometers at 48 m depth in the accumulation zone, across the main deep-seated sliding surface. Results show an acceleration of movements, both at surface and at depth, soon after the massive snow accumulation event of 31st January to 2nd February 2014, which suddenly increased snow thickness from 1 to more than 2 metres. Short time lags between the onset of the acceleration of movements in the source, the track and the accumulation zones were also recorded. The landslide then maintained a relatively constant velocity during the high snow cover period extended to earlyApril and underwent a progressive deceleration during the snowmelt period that lasted until mid-June. The fact that the acceleration of the Corvara earthflow was triggered by a massive and rapid snow accumulation event, provides a quite different perspective from the generally adopted one that considers the destabilizing effect of snow only in relation to the increase of groundwater level during rapid snowmelt. A full explanation of the processes associated to the dynamics observed in Corvara is undoubtedly still an open issue. However, it can be tentatively speculated that in the some sectors of the source and track zone, where sliding surfaces are relatively shallow -around 15 m deep -, the weight of the copiously fallen snow induced a distributed undrained loading in the already fully saturated and confined landslide mass. Or, alternatively, that snow accumulation over the unfrozen soil induced groundwater levels above the ground. To explain how acceleration of movements occurred as deep as 48 m in the accumulation zone, it might be argued that the mass and/or the pore pressure transfer from the track to the accumulation zone - evidenced by the time lag of velocity peaks- can have played a role in indirectly transferring to the accumulation zone the acceleration induced by massive snowfall in the track zone. To provide more robust answers, further monitoring data collection and analysis is needed. Thus, while waiting for other massive snowfall events, three continuous GPS receivers and a water pressure transducer in the soil havebeen added to the monitoring network during 2014.

2015 - Application of persistent scatterers interferometry time-series analysis (PS-time) to enhance the radar interpretation of landslide movements [Capitolo/Saggio]
Franceschini, Silvia; Iannacone, Jean Pascal; Berti, Matteo; Corsini, Alessandro; Simoni, Alessandro

In the last few years, the success of Persistent Scatterers Interferometry (PSI) techniques has largely increased because of the ever enhanced availability of space born radar data. Recently, various authors worked about using PSI techniques in order to better understand slope movements in general and in particular landslides kinematic. PS-time approach represents a new method for the automatic classification of PSI time series based on a conditional sequence of statistical tests. Time series are classified into distinctive predefined target trends, such as uncorrelated, linear, quadratic, bilinear and discontinuous, that describe different styles of ground deformations, so this new approach can be successfully used to improve the radar interpretation of land-slide movements. In this paper we present the results of the application of PS-time to two unstable areas in Northern Apennines of Italy (San Benedetto Val di Sambro, Province of Bologna; Vairo, Province of Parma). Results show that the time series analyis can greatly improve our understanding of the deformation phenomena, and pro-vide useful information in addition to the conventional analysis based on the mean velocity alone. .

2015 - Characterization of longwall mining induced subsidence by means of automated analysis of insar time-series [Capitolo/Saggio]
Iannacone, J. P.; Corsini, A.; Berti, M.; Morgan, J.; Falorni, G.

We present an automated time series analysis of InSAR data for the characterization of ground subsidence induced by longwall mining at Metropolitan mine (New South Wales, Australia). The dataset derives from SqueeSAR™ processing of two Envisat radar data stacks of 44 images acquired from the ascending orbit and 43 from a descending orbit, acquired on a 35-day repeat interval in the period June 2006 to September 2010. Automated time series classification was carried out with PSTime, a specifically designed software that employs a sequence of statistical tests to classify the time series into the six different classes: uncorrelated, linear, quadratic, bilinear, discontinuous without constant velocity and discontinuous with change in velocity. Results highlight a cluster of bilinear trends with acceleration at the front of longwall panel progression and a cluster of bilinear trends with deceleration at the back. Linear trends are found at the centre of the subsidence bowl while outside most trends are uncorrelated. This picture is consistent with the evidence of acceleration in deformation trend when mining is approaching and a deceleration after extraction is completed and an essentially constant while mining takes place just underneath a specific point. Thus, time series analysis proved to be valuable for subsidence dynamics characterization, constraining in space and time the patterns of deformation trend in mining applications.

2015 - Characterizing the Recharge of Fractured Aquifers: A Case Study in a Flysch Rock Mass of the Northern Apennines (Italy) [Relazione in Atti di Convegno]
Cervi, F.; Corsini, Alessandro; Doveri, M.; Mussi, M.; Ronchetti, Francesco; Tazioli, A.

12 springs from the northern Apennines of Italy were studied by means of a comprehensive hydrogeological investigation to unravel recharge processes taking place in a highly fractured slab of flysch rock hosting the corresponding aquifers. Several campaigns were carried out during the period 2005–2008 to gather springs’ discharge together with electrical conductivity and temperature data. Water samples were collected and allowed the determination of the major ions (Ca2+, Mg2+, Na+, K+, SO4 2−, HCO3 −, Cl−) and the isotopic content (δ18O). Additionally, groundwater discharge from 3 selected springs was measured continuously using pressure-transducers. Over the same period, reference δ18O values for rainfall and snow-melt water were collected monthly by a rain-gauge. Results highlighted an aquifer-like behavior of this slab of flysch rock. The springs are characterized by a Ca–HCO3 hydro-facies and an increase of groundwater mineralization has been noticed moving toward the base of the slab; the mean discharges are between 0.3 and 0.7 l·s−1 and suffered a marked variability during the year; the total maximum yield is about 155,000 m3 while the total discharge volume is around 320,000 m3·y−1. By processing the δ18O isotope values from springs (mean annual values ranged from −9.67 and −10.42 ‰) and by combining them with rainfalls datasets, results show that the main aliquot of recharge occurs in the winter—spring months and it is principally related to the solid precipitations (snow-melt).

2015 - Cross-correlation and time-lag analysis of high frequency monitoring data of the Vallcebre landslide (Eastern Pyrenees, Spain) to reveal cause-effect relationships between variables governing slope instability [Abstract in Atti di Convegno]
Mulas, Marco; Moya, Jose; Corsini, Alessandro; Corominas, Jordi

The Vallcebre landslide is a slow moving large landslide located 140 km north of Barcelona in the Eastern Pyrenees. Monitoring data of the Vallcebre landslide represent a singular case of multi parameter high-frequency monitoring system set up in 1996 and still ongoing. Data of movements and groundwater levels are measured and recorded with a frequency of 20 minutes in 6 boreholes distributed in the landslide, each one equipped with a wire extensometer and a piezometer, while rainfall is recorded by a specific gauge at the site. Data from 3 boreholes recorded during three full years of measurements (from 1999 to 2001) have been analyzed by means of a cross-correlation function in order to determine the reciprocal interdependency and the relative time lag between rainfall, groundwater and movement rate maxima and, ultimately, to evidence cause-effect processes occurring along the slope. It should be pinpointed that, in this specific case, rainfall is also a proxy for the discharge level of the stream eroding the toe of the landslide, that is believed to be one of the main instability factors. The cross-correlation function is a quite simple signal processing tool for measuring similarities of waveforms as function of an applied time-lag. Specifically, it was applied to study: i) the relations between rainfall and movement rate, so to highlight the relative time lag for rainfall to produce an effect in different points of the landslide; ii) the inter-dependencies between different movement rates in the three boreholes in order to determine the pattern of mobilization of the landslide (from up to down slope and vice-versa); iii) the response of groundwater with respect to rainfall, which reflects the local permeability; iv) the evolution of groundwater levels in the three monitoring points. Altogether, results confirm and constrain in time the retrogressive trend of movements in the landslide (in agreement with a 2D numerical model previously developed by Ferrari et. al. 2011) and the driving role of stream undercutting the toe of the landslide, as the acceleration of movements at the lower borehole has the shortest time lag with respect to rainfall, disregard the fact that groundwater level raise earlier in the upper piezometers. Finally, the in-depth analysis of time-lags between movement rates along the slope, allowed highlighting compression and tensile phases in different zones along the longitudinal cross section of the landslide.

2015 - Debris flows in Val Parma and Val Baganza (northern Apennines) During the October 2014 alluvial event in Parma Province (Italy) [Articolo su rivista]
Corsini, Alessandro; Ciccarese, Giuseppe; Berti, Matteo; Diena, Michela; Truffelli, Giovanni

During the October 2014 alluvial event in Parma province, which also caused the city of Parma to be partially flooded, several debris flows affected the upper Val Parma and Val Baganza (northern Apennines, Italy) causing severe and widespread damages to check-dams, roads and other infrastructures. The meteorological event reached intensities as high as 80 mm/hour, which is well above the thresholds presented in literature for the alpine area. The result was the occurrence of tens of debris flow along the Mt. Cervellino - Mt. Vitello relief, which were triggered in zones of failure of slope debris coverage along the streams, remobilized and scoured debris along the track and destroyed several check dams and damaged roads that were overflown by debris. Since debris flows in the northern Apennines are considered quite rare events, their hazard is generally underestimated or overlooked. The event in the Parma province, at the opposite, warns against this potentially destructive events that, in a changing meteorological framework, might result much more frequent and widespread than expected also in the northern Apennines.

2015 - Geomechanical assessment of the Corvara earthflow through numerical modelling and inverse analysis [Articolo su rivista]
Schädler, W.; Borgatti, L.; Corsini, Alessandro; Meier, J.; Ronchetti, Francesco; Schanz, T.

This research proposes a conceptual approach for analysis and numerical modelling of the hydromechanical behaviour of large landslides, applied to one of the source areas of the Corvara earthflow (Dolomites, Italy). The approach consists of two steps: forward calculation and inverse analysis. For the forward calculations, the geological model of the slope considering several shear zones delimitating landslide units was developed, based on a detailed dataset of field investigation and monitoring data. A viscoplastic constitutive model was used to describe the time-dependent material behaviour, i.e. the creep, of the shear zones. The transient distribution of pore water pressure in the slope was considered by means of an additional purely hydrogeological model. These results were used as averaged hydraulic boundary conditions in the calculation of stress and deformation fields with the continuum finite element method (FEM). The numerical model was then calibrated against ground surface displacement rates measured by D-GPS, by iteratively varying the material parameters of the shear zones. For this task, an inverse analysis concept was applied, based on statistical analyses and an evolutionary optimisation algorithm. The inverse modelling strategy was further applied to gather statistical information on model behaviour, on the sensitivity of model parameters and on the quality of the obtained calibration. Results show that the calibrated model was able to appropriately simulate the displacement field of the earthflow and allow the requirements, difficulties and problems, as well as the advantages and benefits of the proposed numerical modelling concept to be highlighted.

2015 - Hydrogeology, Hydrochemistry and Isotopic Investigation to Define the Lateral Hydraulic Boundaries of a Deep Rock Slide (Berceto Landslide: Northern Apennines) [Relazione in Atti di Convegno]
Deiana, Manuela; Cervi, F.; Corsini, Alessandro; Ambanelli, A.; Diena, M.; Lopardo, L.; Truffelli, G.; Ronchetti, Francesco

The Berceto landslide is a deep and active rock slide located in the northern Apennines. It affects a slope characterised by the overlapping of flysch and shale formations. The landslide has been monitored since the 1990s and an inclinometer installed in the head zone shows a sliding surface at the depth of 110 m. The landslide and the adjacent areas are affected by morphological anomalies in the slopes and in the surface drainage patterns. These anomalies are related to the presence of deep landslide or to the presence of faults in the bedrock. In particular, the River Baganza (RB) is situated at about 100 m upstream of the landslide main scarp and it is separated from the landslide by a thin layer of shale. The RB streambed is located at an elevation 70 m higher than the elevation of the active sliding surface. Due to these morphological anomalies, it is possible to speculate that the present extension of the landslide limit is not correct and that the landslide sliding surface could be extended as far as the RB. In this study, hydro-chemical and isotopic investigation have been carried out on the Berceto rock slide in order to define the lateral hydraulic boundary, the geometry of the slide surface and the groundwater flow paths. The ion contents and the δ18O-δ2H values indicate the presence in the landslide body of an external source of groundwater which could be provided by the RB through a sliding surface developed within the shale or by the flysch below the landslide body.

2015 - Integration of X-band SAR interferometry , continuous and periodic D-GPS and in-place inclinometers to characterize and monitor a deep-seated earthslide in the Dolomites ( Italy ) [Abstract in Atti di Convegno]
Mulas, Marco; Corsini, Alessandro; Soldati, Mauro; Marcato, Gianluca; Pasuto, Alessandro; Crespi, Mattia; Mazzoni, Augusto; Benedetti, Elisa; Branzanti, Mara; Manunta, Michele; Ojha, Chandrakanta; Chinellato, Giulia; Cuozzo, Giovanni; Costa, Armin; Monsorno, Roberto; Thiebes, Benni; Piantelli, Elena; Magnani, Massimo; Meroni, Marco; Mair, Volkmar

The Corvara landslide is an active, large-scale, deep-seated and slow moving earthslide of about 30 Mm3 located in the Dolomites (Italy). It is frequently damaging a national road and, occasionally, isolated buildings and recreational ski facilities. Since the mid ‘90s it has been mapped, dated and monitored thanks to field surveys, boreholes, radiocarbon dating, inclinometers, piezometers and periodic D-GPS measurements, carried out by the Geology and the Forestry Planning offices of the Autonomous Province of Bolzano, the Municipality of Corvara in Badia, the University of Modena and Reggio Emilia, the IRPI-CNR of Padua. In 2013, a new phase of characterization and monitoring has started which also involves the EURAC’s Institute for Applied Remote Sensing, the geodesy group of University La Sapienza, the CNR-IREA of Naples and the Leica Geosystems office in Italy. This new phase of characterization and monitoring is meant to investigate the opportunities of innovative SAR interferometry, D-GPS and in-place inclinometers techniques to provide for a high frequency monitoring of the study site in support to the analysis of the investigation of forcing factors leading unsteady, nonuniform landslide motion through different seasons of the year. Monitoring results are also expected to provide a validation of innovative interferometric techniques so to fully evaluate their conformity to be used as a long-term monitoring system in land-use planning and risk management procedures. The monitoring infrastructure now integrates: 16 Corner Reflector for satellite X-Band SAR interferometric products, 13 benchmarks for D-GPS periodic surveys, three on-site GPS receivers for continuous positioning and remote ftp data pushing, two in-place inclinometers and a pressure transducer to record pore-pressure variations. The coupling of SAR-based products with GPS records is achieved using especially designed Corner Reflectors having an appendix dedicated to hold Dual-Frequency GPS antennas. COSMO-SkyMed X-Band SAR acquisitions started on October 2013 and are ongoing with a temporal resolution of 16 days using STRIPMAP (HIMAGE) measuring mode. Discontinuous D-GPS Fast-Static surveys are scheduled with a triple frequency: annual for 24 points outside recent activation areas, monthly for 13 points in the active zone and a bi-weekly for 6 points located in the most active zone. Displacement high-frequency data are acquired thank to the installation of 3 Dual-Frequency GPS in permanent acquisition that have been located in the accumulation, track and source zone of the active portion of the landslide. High frequency data are also obtained by the two inclinometers operating in continuous acquisition located across the main slide surface at 48 m depth into a 90 m borehole drilled in the accumulation zone. A piezometer installed in the source zone and the meteorological station of Piz La Ila (3 km far away) of the Autonomous Province of Bolzano complete the system.

2015 - Interaction of Extremely Slow Landslides with Transport Structures in the Alpine Glacial Isarco Valley [Relazione in Atti di Convegno]
Simeoni, L.; Ronchetti, Francesco; Corsini, Alessandro; Mongiovì, L.

This paper describes three cases of extremely slow landslides located in the Isarco Valley, and interacting with major transport infrastructures connecting Italy to the central Europe: SS12 State Road, A22 (E45) Motorway, Verona-Brennero railway, high-speed railway network TNT-T5. Field measurements of displacements and pore water pressure were carried out to understand the mechanism of landslide evolution and the interaction with the transport structures. In particular, mobile inclinometers, IPIs, direct pendula and Total Station were used for monitoring the subsurface or structure movements. The landslides were classified as complex landslides. Two of them are associated to DGSDs phenomena. Field and remote measurements of displacements revealed that the interaction with the transport infrastructures was due to deep rotational/translational slides as partial reactivations of the DGSDs. The residual shear strength was developed on the sliding surfaces and therefore these landslides may be classified as active landslides.

2015 - Long-Term Continuous Monitoring of a Deep-Seated Compound Rock Slide in the Northern Apennines (Italy) [Relazione in Atti di Convegno]
Corsini, Alessandro; Bonacini, F.; Mulas, Marco; Petitta, M.; Ronchetti, Francesco; Truffelli, G.

An automated total station monitored a compound rock slide near the Cerreto Pass (northern Apennines, Italy) for more than three and a half years. The rock slide, which threatens national road SS63, has an estimated volume of more than 3 million m3 and is composed by the overlap of highly fractured limestone on an impermeable and weak clay shale layer. Specifically, a network of more than 30 prisms has been measured every 2 h from October 2009 to May 2013. This dataset provides substantial evidence of displacement rates up to 15 cm/year and gives information about the control of rainfall on slope movements. On the yearly scale the seasonal variation of rainfall regime determines the baseline displacement rate of the rockslide while moving to shorter time spans has been possible to individuate effects of rain episodes calculated on daily and weekly sampling. Results highlight the added value of continuous monitoring for assessing rock slide dynamics and improving hazard assessment.

2015 - Long-term monitoring of a deep-seated, slow-moving landslide by mean of C-band and X-band advanced interferometric products: the Corvara in Badia case study (Dolomites, Italy) [Articolo su rivista]
Mulas, Marco; Petitta, M.; Corsini, Alessandro; Schneiderbauer, S.; Mair, F. V.; Iasio, C.

The availability of data from various Synthetic Aperture Radar (SAR) operating in X-Band and C-Band acquired in the last decades enables to monitor slopes affected by landslides. The ASI-founded project ‘LAWINA’ (2010 – 2012) aimed at the improvement of SAR – based monitoring techniques as well as at the integration of SAR data with data stemming from other sensors. Test case area of LAWINA has been a slow-moving landslide located up-stream of Corvara in Badia village in the Dolomites, Italy. Within the scope of the project different time-series obtained through 35 Envisat2, 40 Radarsat-1 and 46 Cosmo-SkyMed covering this test area have been processed in order to explore the potentials to analyse historical and near real time landslide dynamics. The SAR data are characterized by various geometric and temporal resolutions having been acquired by 3 sensors operating at different bands in different periods between 2003 and 2011. TeleRilevamento Europa (TRE) exploited these data in order to retrive displacement time- series applying its proprietary SqueeSAR algorithm. After re-projecting Envisat-2 and Radarsat datasets according to the CSK Line Of Sight a comparison of displacements recorded by each sensor has been possible. For this purpose, we have selected areas characterized by the presence of Persistent Scatterers or Diffused Scatterers from at least two datasets. This multi-sensor approach allowed determining the slope displacement tracking during 8 years. Even though the different time series are not formally integrated each other, the result is accurate enough to allow the evaluation of the landslide’s behaviour and trend over several years

Deiana, Manuela; Corsini, Alessandro; Mussi, Mario; Ciccarese, Giuseppe; Giusti, Riccardo; Ronchetti, Francesco

Fractured sandstone by tectonic and gravity actions could be classified as aquitard or aquifer according to the number and aperture of the fractures inside the rock mass. This kind of rock mass outcrops not frequently and sparsely in the Apennine and Alps chains. In the Emilian Apennines, which is mainly composed by sedimentary rocks (rich in clay), this type of rock is part of the Epiligurian Succession that outcrops for a 20 percent of the chain. The paper aims to highlight the first results of the semi-continuous water flow monitoring (discharge, electrical conductivity and temperature) and stable isotopic monitoring (delta18O and delta2H) of the spring that represents the drainage point of a vertical fractures system. This network joint characterizes the vertical scarp of a sandstone slab with thickness of 100 meters. The results show that the spring flow rate, the water electrical conductivity, temperature and isotopic values are influenced by the rainfall distribution pattern. Consequently during every rainfall event the spring discharge and water electrical conductivity increase, while the water temperature decreases and isotopic values become more negative. The new infiltrate water reachs the spring with a delay of 10-60 hours. The discharge variability index is around 270 percent. The fractured system is characterized by replacement effect of the preexistent groundwater. During the infiltration event, dissolution phenomena are observed along the wall of the fractures. A preliminary groundwater budget calculation highlights that only a potential infiltration coefficient higher that 75 percent is admitted to justify the total annual volume discharge from the fractures.

2015 - Partial reactivation of a DGSD of ignimbrite and tuff in an alpine glacial valley in Northern Italy [Relazione in Atti di Convegno]
Simeoni, L.; Ronchetti, Francesco; Corsini, Alessandro; Mongiovì, L.

This paper describes the surveys, site investigations, field measurements and laboratory tests carried out to analyze the stability of a slope in the Isarco alpine glacial valley, in Northern Italy, where rocks and debris of ignimbrite and tuff outcrop. This valley is crossed by the major transport infrastructures connecting Italy to the central Europe: SS12 State Road,A22 (E45) Motorway, Verona-Brennero railway, high-speed railway network TNT-T5. Recently, large deformations of the pads of a viaduct were identified and were supposed to be caused by the downslope movement of the piers. In effect, subsequent investigations and measurements revealed the existence of sliding surfaces with movements smaller than 1 cm per year. Surveys identified that movements occur at the toe of a DGSD and back-analyses revealed that the residual shear strength estimated with shearbox tests is mobilized on the sliding surfaces.

2015 - Prediction of landslide velocity at given cumulated rainfall values based on analysis of continuous monitoring data using ROC curves : application to the Piagneto landslide ( Northern Apennine , Italy ) [Abstract in Atti di Convegno]
Corsini, Alessandro; Mulas, Marco; Petitta, Marcello; Bonacini, Francesco; Ronchetti, Francesco

A novel approach to predict landslide velocity at given cumulated rainfall values based on the analysis of continuous displacement and rainfall monitoring data by using ROC curves has been developed and tested in the Piagneto landslide (northern Apennines, Italy). It is an active rock slide for which a velocity dataset covering the period October 2009 to December 2014 is available thanks to a total station that has been monitoring tens of prisms at duty cycles of 2 hours. Over the same time frame, an hourly rainfall dataset is available from rain gauges located just a few km away from the landslide. The ROC curve (Receiver Operating Characteristic) is a well-known and widely used method to assess the efficiency of a binary classifier. In this case, it is used to assess the efficiency of different values of cumulated rainfall to determine a given value of velocity in the landslide. Operatively, the daily velocity distributions of selected monitoring prisms is plotted in order to assess upper values at given levels of occurrence probability, i.e. velocity values at the upper 1st,2nd, 3rd quartile and 2 sigma. These velocity values are then classified with respect to daily rainfall cumulated over different time windows (from 1 to 120 days), that are considered singularly or in combination one another. The area under the ROC curves, as well as the max distance from the random line, is used as indicator of performance in order to assess the cumulated rainfall (in terms of amount and duration) showing the higher performance in predicting a defined landslide velocity level. The values obtained with the retrospective analysis of monitoring data, can then be used for prediction of expected velocity levels. This has been verified by using the conventional approach of dividing the dataset in a training and a validation subsets. Results underline the added value of the analysis of long time-series of continuous landslide monitoring data by mean of operational research tools, such as in this case the ROC curves, for extracting information useful for improving the comprehension and the prediction of slope dynamics that, in specific cases, can be of great support to risk management.

2015 - Preliminary water flow monitoring of a vertical fractures system in a sandstone rock mass [Articolo su rivista]
Deiana, M.; Bonacini, F.; Cilona, F.; Formicola, M.; Nistor, M. M.; Corsini, A.; Ronchetti, F.

Fractured sandstone by tectonic and gravity actions could be classified as aquitard or aquifer according to the number and aperture of the fractures inside the rock mass. This kind of rock mass outcrops not frequently and sparsely in the Apennine and Alps chains. In the Emilian Apennines, which is mainly composed by sedimentary rocks (rich in clay), this type of rock is part of the Epiligurian Succession that outcrops for a 20% of the chain. The aim of the paper is to highlight the first results of the semi-continuous water flow monitoring (discharge, electrical conductivity and temperature) of the spring that represents the drainage point of a vertical fractures system. This network joint characterizes the vertical scarp of a sandstone slab with thickness of 100 meters. The results shows that the spring flow rate, the water electrical conductivity and temperature are influenced by the rainfall distribution pattern. Consequently every rainfall event the spring discharge and water electrical conductivity increase, while the water temperature decreases. The new infiltrate water reacts the spring with a delay of 10-60 hours. The discharge variability index is around 270%. The fractured system is characterized by replacement effect of the preexistent groundwater. During the infiltration event, dissolution phenomena are observed along the wall of the fractures. A preliminary groundwater budget calculation highlights that only a potential infiltration coefficient higher that 75% is admitted to justify the total annual volume discharge from the fractures.

2015 - Water isotopes in landslide research (WIsLaR) [Abstract in Atti di Convegno]
Deiana, Manuela; Cervi, Federico; Corsini, Alessandro; Mussi, Mario; Pennisi, Maddalena; Ronchetti, Francesco

In the last decade, the scientific community is trying to integrate multidisciplinary approaches to gain further insights in the knowledge of landslide initiation and evolution. In particular, isotope geochemistry is a useful investigation tool to define landslide groundwater recharge origin, groundwater flow paths, mixing phenomena between different water bodies, type of aquifer, type of groundwater transfer processes (only pressure or pressure and mass). This paper aims at pointing out the potentiality of stable and radiogenic isotopic analyses in the study of large and deep rock landslides located in north Apennines. In the studied landslides, the continuous monitoring of groundwater levels, groundwater flow rate from springs or mitigation works, groundwater electrical conductivity and temperature are coupled with groundwater sampling followed by determination of major and tracers ions (such as: Na+, K+, Mg2+, Ca2+, Cl-, HCO3-, SO42-,Btot, Sr2+), and stable (delta 18O, delta 2H,) and radiogenic isotopes (87Sr/86Sr, 3H). In this study isotopic investigations are decisive to understand hydrological processes in landslide body. More in details delta 18O, delta 2H, 87Sr/86Sr and 3H allow to define subsurface architecture, groundwater origin, groundwater flow paths and mixing phenomena between different groundwater bodies. Recharge zones are identify by means of delta 18O and delta 2H isotopes. 3H gives information about groundwater age and allows to identify deep confined layer characterized by low circulation of water and to investigate subsurface transfer processes. In the current research 3H allows to identify a deep confined aquifer in which pressure transfer prevails on mass transfer. Subsurface layers with prevalent horizontal or vertical flux are identified by means simultaneous application of delta 18O, delta 2H and 3H. The simultaneous application of delta 18O, delta 2H, 3H and 87Sr/86Sr allows to recognize hydraulic connections between groundwater and surface water. Moreover, 87Sr/86Sr coupled with 3H allow to identify multilayer aquifer within the landslide body.

2014 - A reliable methodology for monitoring unstable slopes: the multi-platform and multi-sensor approach [Relazione in Atti di Convegno]

High resolution topography, by involving Digital Terrain Models (DTMs) and further accurate techniques for a proper displacement identification, is a valuable tool for a good and reliable description of unstable slopes. By comparing multitemporal surveys, the geomorphology of a landslide may be analyzed as well as the changes over time, the volumes transportation and the boundaries evolution. Being aware that a single technique is not sufficient to perform a reliable and accurate survey, this paper discusses the use of multi-platform, multi-source and multi-scale observations (both in terms of spatial scale and time scale) for the study and monitoring of unstable slopes. The final purpose is to highlight and validate a methodology based on multiple sensors and data integration, useful to obtain a comprehensive GIS (Geographic Information System) which can successfully be used to manage natural disasters or to improve the knowledge of a specific phenomenon in order to prevent and mitigate the hydro-geological risk. The novelty of the present research lies in the spatial integration of multiple remote sensing techniques such as: integration of Airborne Laser Scanning (ALS) and Terrestrial Laser Scanning (TLS) to provide a comprehensive and accurate surface description (DTM) at a fixed epoch (spatial continuity); continuous monitoring by means of spatial integration of Automated Total Station (ATS) and GNSS (Global Navigation Satellite System) to provide accurate surface displacement identification (time continuity). Discussion makes reference to a rockslide located in the northern Apennines of Italy from 2010 to 2013. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

2014 - Disaster Mitigation by Corrective and Protection Measures [Capitolo/Saggio]
Olga Christina, Mavrouli; Corsini, Alessandro; Jordi, Corominas

Mavrouli et al. (Chap.11) distinguish two different strategies for corrective and protective measures for the mitigation of landslide risk, namely stabilization/interception measures and control measures. A variety of mitigation measures are presented for three different landslide types: rockfalls, debris flows and shallow to deep seated slope movements.

2014 - Frane a cinematica estremamente lenta in una valle glaciale del corridoio TEN-T5 [Relazione in Atti di Convegno]
Simeoni, L.; Ronchetti, Francesco; Corsini, Alessandro; Mongiovì, L.; Ferro, E.; Ghirardini, G.; Girardi, M. F.

La memoria descrive tre casi di frane a cinematica estremamente lenta (velocità di spostamento media inferiore a 10 mm/anno) ubicate nella valle glaciale alpina dell’Isarco, tra Bolzano e Bressanone. Le tre frane sono riattivazioni parziali di DGPV, sviluppatesi dopo l’ultima glaciazione in rocce vulcaniche o metamorfiche e si classificano come scorrimenti rotazionali profondi di roccia e detrito. Si descrivono i sistemi di monitoraggio di spostamenti e pressioni interstiziali, attivi da un minimo di 5 anni ad un massimo di 20, che sono stati installati per la definizione dei meccanismi di evoluzione dei movimenti. Si evidenziano i metodi di elaborazione delle misure, finalizzati al controllo dell’affidabilità delle stesse, e si riportano le interpretazioni dei meccanismi di frana effettuate mediante verifiche di stabilità a ritroso.

2014 - Innovative Techniques for the Characterization of the Morphology, Geometry and Hydrological Features of Slow-Moving Landslides [Capitolo/Saggio]
Ulrich, Kniess; Julien, Travelletti; Alexander, Daehne; Dominika, Krzeminska; Gregory, Bievre; Denis, Jongmans; Corsini, Alessandro; Thom, Bogaard; Jean Philippe, Malet

highlight the interest of combining different techniques obtained from numerous developments in remote-sensing, near-surface geophysics, field instrumentation and data processing. In a number of case studies, they show significant advances in characterizing the landslide morphology and internal structure

2014 - Innovative Techniques for the Detection and Characterization of the Kinematics of Slow-Moving Landslides [Capitolo/Saggio]
Ping, Lu; Alexander, Daehne; Julien, Travelletti; Nicola, Casagli; Corsini, Alessandro; Jean Philippe, Malet

The chapter introduces several innovative remote-sensing techniques to monitor and analyse the kinematics of slow moving to moderately moving landslides. These are illustrated in three case studies in Italy and France

2014 - Integrazione tra indagini geofisiche e geognostiche per la definizione di un modello geologico e geotecnico di grandi frane profonde: il caso di Berceto nell’Appennino Settentrionale [Relazione in Atti di Convegno]
Ambanelli, A.; Ambrogio, A.; Baldi, A. M.; Bianchi, F.; Corsini, Alessandro; De Luca, J.; Deiana, Manuela; Diena, M.; Larini, G.; Lopardo, L.; Malaguti, C.; Mencarini, S.; Ronchetti, Francesco; Roverselli, D.; Truffelli, G.; Vescovi, P.

L’Appennino Settentrionale è caratterizzato dalla presenza di numerose frane con Deformazione Gravitativa Profonda di Versante (DGPV), a carattere cinematico lento. Una di queste interessa il versante di Berceto e presenta un’estensione di 3-4 km223 , una profondità di oltre 100 metri e un tasso di movimento nell’ordine di alcuni mm/anno, coinvolgendo l’intero abitato ed un tratto dell’Autostrada della Cisa (A15). La Regione Emilia-Romagna ha avviato, da alcuni anni, campagne di indagini geognostiche e geofisiche per la definizione del modello geologico e geotecnico di tale fenomeno. Le caratteristiche geometriche della massa coinvolta hanno reso necessaria indagini geofisiche di superficie (geoelettrica e sismica) e sondaggi geognostici indispensabili per la taratura puntuale dei dati indiretti e per l’installazione di strumentazioni inclinometriche, estensimetriche-assestimetriche e piezometriche. I risultati, interpretati alla luce delle evidenze stratigrafiche hanno consentito, congiuntamente ai dati idrogeologici e di monitoraggio degli spostamenti, la ricostruzione di un primo modello geologico e geotecnico.

2014 - Remotely Piloted Aircraft Systems (RPAS) for high resolution topography and monitoring: civil protection purposes on hydrogeological contexts [Relazione in Atti di Convegno]
BERTACCHINI, Eleonora; CASTAGNETTI, Cristina; CORSINI, Alessandro; De Cono, Stefano

The proposed work concerns the analysis of Remotely Piloted Aircraft Systems (RPAS), also known as drones, UAV (Unmanned Aerial Vehicle) or UAS (Unmanned Aerial System), on hydrogeological contexts for civil protection purposes, underlying the advantages of using a flexible and relatively low cost system. The capabilities of photogrammetric RPAS multi-sensors platform were examined in term of mapping, creation of orthophotos, 3D models generation, data integration into a 3D GIS (Geographic Information System) and validation through independent techniques such as GNSS (Global Navigation Satellite System). The RPAS used (multirotor OktoXL, of the Mikrokopter) was equipped with a GPS (Global Positioning System) receiver, digital cameras for photos and videos, an inertial navigation system, a radio device for communication and telemetry, etc. This innovative way of viewing and understanding the environment showed huge potentialities for the study of the territory, and due to its characteristics could be well integrated with aircraft surveys. However, such characteristics seem to give priority to local applications for rigorous and accurate analysis, while it remains a means of expeditious investigation for more extended areas. According to civil protection purposes, the experimentation was carried out by simulating operational protocols, for example for inspection, surveillance, monitoring, land mapping, georeferencing methods (with or without Ground Control Points - GCP) based on high resolution topography (2D and 3D information).

2014 - The Relevance of Early-Warning Systems and Evacuations Plans for Risk Management [Capitolo/Saggio]
Carolina, Garcia; Simone, Frigerio; Daehne, Alexander; Corsini, Alessandro; Simone, Sterlacchini

Garcia et al. (Chap. 13) analyse different types of Early-Warning Systems with the aim to connect scientific advances in hazard/risk assessment with local management strategies and practical demands of stakeholders/end-users. An Integrated People-Centred Early Warning System (IEWS) is presented, which is mainly based on prevention as a key element for disaster risk reduction

2014 - Utilizzo d'immagini all'infrarosso termico per l'individuazione di sorgenti minerali nella Finestra Tettonica di Gova [Articolo su rivista]
Ronchetti, Francesco; F., Cervi; Corsini, Alessandro; P., Mora; G., Maragò; S., Taddia

L’utilizzo di immagini all'infrarosso termico da piattaforma satellitare, aerea e terrestre è oramai consolidato in diverse discipline tra le quali l’ingegneria civile, l’architettura, l’idrologia, l’idrogeologia, l’agronomia e la climatologia. A partire dagli ultimi anni, le termocamere forniscono preziose informazioni per la valutazione della dispersione di energia termica dagli edifici mentre in campo ambientale, vengono impiegate per monitorare vulcani, prevenire e controllare incendi, controllare discariche, rilevare fughe gas, valutare l'umidità del suolo, monitorare/caratterizzare frane e pareti rocciose, classificare l’uso del suolo, controllare la dispersione di inquinanti in fiumi, individuare sorgenti in alveo e stimare la loro portata, indagare la presenza di sorgenti sottomarine lungo le coste (Danielescu et al. 2009). Una trattazione esaustiva delle possibili applicazioni di questa tecnica in campo idrogeologico ed ambientale si trova in Brunner et al. (2007). Nella presente nota viene riportato l'utilizzo dell’infrarosso termico mediante termocamera da piattaforma terrestre per la localizzazione di alcune sorgenti minerali che vengono a giorno in modo diffuso nell’alveo del Torrente Dolo (Comune di Toano, Provincia di Reggio Emilia). Si tratta delle sorgenti fredde e minerali di Quara, già sfruttate fin da epoca romana, ad oggi in larga parte scomparse e sepolte da alluvioni recenti. Il sito è inoltre inserito tra le aree di particolare interesse nell’analisi preliminare per la valutazione del potenziale geotermico in Regione Emilia Romagna.

2014 - Valutare la vulnerabilità dei corpi idrici a scala locale [Articolo su rivista]
Ronchetti, Francesco; Corsini, Alessandro; F., Cervi; M. M., Nistor; F., Petronici; D., Errigo; M., Marcaccio

Il progetto il progetto ha lo scopo di valutare la vulnerabilità delle risorse idriche potabili in funzione del cambiamento climatico e delle variazioni degli aspetti socio-economici della zona montana dell’Appennino della Regione Emilia Romagna. Tale vulnerabilità è intesa sia in termini quantitativi, come la disponibilità futura della risorsa idropotabile, che in termini qualitativi, intesa come futura potabilità della risorsa stessa. Inoltre il progetto ha lo scopo di valutare la funzione dei servizi ecosistemici relativamente all’azione mitigatrice della vulnerabilità della risorsa idrica sotterranea e di fornire linee guida per una corretta regolamentazione dell’uso del suolo nelle zone di ricarica dei corpi idrici sotterranei in zone montane.

2014 - Vulnerability of groundwater in fractured aquifers, under climate and land use change in northern Apennines [Relazione in Atti di Convegno]
Nistor, M. M.; Ronchetti, Francesco; Corsini, Alessandro; F., Cervi; L., Borgatti; D., Errigo; M., Marcaccio

Vulnerability of groundwater in fractured aquifers

2013 - Automated classification of Persistent Scatterers Interferometry time series [Articolo su rivista]
M., Berti; Corsini, Alessandro; S., Franceschini; Iannacone, JEAN PASCAL

We present a new method for the automatic classification of Persistent Scatters Interferometry (PSI) time series based on a conditional sequence of statistical tests. Time series are classified into distinctive predefined target trends, such as uncorrelated, linear, quadratic, bilinear and discontinuous, that describe different styles of ground deformation. Our automatic analysis overcomes limits related to the visual classification of PSI time series, which cannot be carried out systematically for large datasets. The method has been tested with reference to landslides using PSI datasets covering the northern Apennines of Italy. The clear distinction between the relative frequency of uncorrelated, linear and non-linear time series with respect to mean velocity distribution suggests that different target trends are related to different physical processes that are likely to control slope movements. The spatial distribution of classified time series is also consistent with respect the known distribution of flat areas, slopes and landslides in the tests area. Classified time series enhances the radar interpretation of slope movements at the site scale, pointing out significant advantages in comparison with the conventional analysis based solely on the mean velocity. The test application also warns against potentially misleading classification outputs in case of datasets affected by systematic errors. Although the method was developed and tested to investigate landslides, it should be also useful for the analysis of other ground deformation processes such as subsidence, swelling/shrinkage of soils, or uplifts due to deep injections in reservoirs.

2013 - Comparative analysis of surface roughness algorithms for the identification of active landslides [Articolo su rivista]
Berti, M.; Corsini, Alessandro; Daehne, Alexander

Parameters correlated to surface roughness are quite commonly used to describe landslide activity in quantitative geomorphology. Previous studies proved that topographic roughness is closely related to both landslide mechanics and features. A number of different techniques have emerged over the years to describe quantitatively the great variety of landforms and processes that affect unstable slopes. In this work we perform a comparative analysis of severalmethods used in literature to compute surface roughness (root mean square applied to elevation and slope grids, eigenvalue ratios, semivariance, discrete Fourier transform, continuous wavelet transform and wavelet lifting scheme) in order to evaluate quantitatively which algorithms are best suited to discriminate active landslides and to predict them for automated mapping purposes. A first test was carried out on artificial surfaces simulating different roughness patterns encountered in nature, so to highlight advantages and limits in controlled conditions. Then, the algorithms were applied to LiDAR datasets of two earth flow case studies in the Northern Apennines, Italy. Results obtained by using “effect-size” statistical test to objectively quantify the capability of the different algorithms of discriminating active landslide slopes from other slope types showed that most algorithms perform reasonablywell and that simple techniques (RMS-based and wavelet lifting scheme) achieve equal or sometimes even better results thatmore complex ones. Results fromthe use of roughness indexes for the prediction of landslide slopes in automated mapping showed that non-forested active slopes could be predicted bymostmethods with an accuracy greater than 85% and that most methods had a 15% drop in prediction accuracy in forested active slopes. Results also proved that increasing the size of the moving window has minor beneficial effects in predictive capability, suggesting that small size of pixels and moving windows should be used to retain a full resolution of surface conditions in slopes.

2013 - Forward simulation and sensitivity analysis of run out scenarios using MassMov2D at the Trafoi rockslide (South Tyrol, Italy) [Articolo su rivista]
Iannacone, J. P.; Quan Luna, B.; Corsini, Alessandro

This paper presents forward simulation with MassMov2D code and sensitivity analysis of run out resulting from different scenarios of potential failure of a 40 million m3 active rockslide hanging above the village of Trafoi, in South Tyrol (Italy). Five scenarios of potential failure zones were identified, with the larger one being the failure of the entire rock slide. Forward simulations showed that the consequences for the Trafoi village would be potentially destructive. A parametric sensitivity analysis was carried out in order to increase the significance of risk assessment. Results obtained by varying friction and turbulent coefficients showed quite unequivocally that although the variability of the run out might be quite large it does not change risk scenarios significantly except in the smaller case of failure. This confirms the usefulness of forward simulations even if they might be affected by uncertainties related to the impossibility to retrieve optimized parameters.

2013 - Forward simulation of displacement rates variations due to groundwater level changes induced by deep drainage wells in Succiso earth slide (northern Apennines, Italy) [Articolo su rivista]
F., Bonacini; G., Caputo; A. B., Costantino; Ronchetti, Francesco; Corsini, Alessandro

The Succiso landslide is a large scale active earth slide located in the northern Apennines of Italy, in the upper Enza river basin (Province of Reggio Emilia, Emilia Romagna Region). It extends from 1075 to 800 m a.s.l., affecting an area of about 0.5 km2 for a length of about 1.6 km and a maximum width of 500 m. The landslide area is characterized by flysch and claystone bedrock, by glacial and landslide deposits of various type and by more than 2000 mm rainfall per year. The landslide is named after the village of Succiso, that was damaged by acceleration of earth slide movements in 1951, 1952 and, quite severely, in 1966 and 1972. Succiso was first declared, according to law 445/1908, as “to be consolidated” (DPR n 201 of 14/02/1957) and, later on, as “to be transferred” (DL n°976 of 18/12/1966 – G.U. 24/4/70). From 1972 to 2008 the landslide did not underwent any other particular acceleration event and presumably, it moved at rates in the order of few cm/year, as it does presently. Consequently, the village of Succiso was again re-classified as “to be consolidated” (DGR n° 686 of 12/05/2008). Following such recent administrative act, and in order to define, design and construct consolidation works, the local technical basin service (Emilia Romagna Region) has undertaken an intensive geological, geotechnical investigation and monitoring survey that allowed to define the geological model and the on-going kinematics of the landslide's deposit. This work describes a geotechnical softsoil-creep model, in order to analysing the potential benefits, in terms of decrease in displacement rates, induced by the building of a deep drainage wells in the Succiso earth slide.

2013 - Forward simulation of groundwater level changes induced by deep drainage wells in Succiso earth slide (northern Apennines, Italy) [Articolo su rivista]
M., Righini; G., Caputo; F., Cervi; Corsini, Alessandro; Ronchetti, Francesco

The Succiso landslide is a large scale active earth slide located in the northern Apennines of Italy, in the upper Enza river basin (Province of Reggio Emilia, Emilia Romagna Region). It extends from 1075 to 800 m a.s.l., affecting an area of about 0.5 km2 for a length of about 1.6 km and a maximum width of 500 m. The landslide area is characterized by flysch and claystone bedrock, by glacial and landslide deposits of various type and by more than 2000 mm rainfall per year. The landslide is named after the village of Succiso, that was damaged by acceleration of earth slide movements in 1951, 1952 and, quite severely, in 1966 and 1972. Succiso was first declared, according to law 445/1908, as “to be consolidated” (DPR n 201 of 14/02/1957) and, later on, as “to be transferred” (DL n°976 of 18/12/1966 – G.U. 24/4/70). From 1972 to 2008 the landslide did not underwent any other particular acceleration event and presumably, it moved at rates in the order of few cm/year, as it does presently. Consequently, the village of Succiso was again re-classified as “to be consolidated” (DGR n° 686 of 12/05/2008). Following such recent administrative act, and in order to define, design and construct consolidation works, the local technical basin service (Emilia Romagna Region) has undertaken an intensive geological, geotechnical investigation and monitoring survey that allowed to define the geological model and the on-going kinematics of the landslide's deposit. This work supports feasibility analysis of a shield of deep drainage wells to be possibly located in the central portion of the landslide (indicatively: 26 wells, diameter 1 m, depth 30 m, inter-axes 7-8 m, total length of shield 200 m, gravity discharge).Specifically, it performs a forward simulation of groundwater level changes induced by this possible deep drainage solution, using an hydrogeological modeling of the landslide based on 3D FEFLOW software, which has been calibrated thank to a continuous piezometric monitoring. A parent paper presented at this conference has complemented the feasibility analysis by using the outputs of this hydrogeological simulation as input to a geotechnical softsoil-creep model, in order to analysing the potential benefits, in terms of decrease in displacement rates, induced by deep drainage wells.

2013 - Hot spots for simplified risk scenarios of the Trafoi rockslide (South Tyrol) [Relazione in Atti di Convegno]
Corsini, Alessandro; Iannacone, J. P.; Ronchetti, Francesco; Salvini, R.; Mair, V.; Nossing, L.; Stefani, M.; Unterthiner, G.; Valentinotti, G.

The Trafoi rockslide is very similar to the Val Pola landslide before it evolved in a catastrophic rock avalanche in 1987. The Trafoi rockslide was recognized and mapped on the basis of geomorphic evidences such as double crests and detachment niches/scarps as well as geologic proxies such as gravitational offset of distinctive bedrock levels and trenching and fracturing of rock masses. In order to assess the activity status of the landslide, not discernible from field evidences only, periodic GPS monitoring on 11 benchmarks was started in 2007 and continued until 2010 with static-rapid measurements repeated 3 to 4 times per year. Results have shown that portions of the rockslide move at some cm/year rate. This highlights the potential for a possible evolution of the mass movement and the necessity of hazard scenarios mapping and run-out modelling. In order to define volume of possible detachments scenarios, digital aerial photo-interpretation were used together with High Resolution DEM and information collected from geomechanical field survey. The Trafoi rockslide is among the test sites of the ongoing European project “Monitor II”, that is proposing the usage of hot spots in the process domain as a practical mean to describe hazard scenarios. Following such approach, simplified hazard and risk scenarios were schematized on the basis of the data collected with monitoring and analysis of ongoing and potential slope instability processes.

2013 - Improve information provision for disaster management: MONITOR II, EU project [Relazione in Atti di Convegno]
Ronchetti, Francesco; Corsini, Alessandro; Kollarits, S.; Leber, D.; Papez, J.; Plunger, K.; Preseren, T.; Schnetzer, I.; Stefani, M.

Management of natural hazards constitutes a common challenge in all country of the world. Until now, neither hazard mapping nor contingency planning have been transnationally coordinated and defined. These gaps will be tackled in MonitorII project (founded by the EU - South East Transnational Cooperation Program) with the development of a common methodology about risk assessment and risk management. The project partnership has so far carried out the following activities and achieved the following results: review of best practices in hazard mapping and contingency plans; definition of information needs and information flows in different phases of risk management; definition of novel concepts for the creation of simplified scenario models in the process, damage and intervention domain. In the project will be developed a Continuous Situation Awareness system, a software that support the disaster management in the different phases of the risk cycle. Within the broad range of hazards, MonitorII specifically deals with floods and landslides, but the concepts of the project could be applied to other types of hazards.

2013 - Integrating airborne and multi-temporal long-range terrestrial laser scanning with total station measurements for mapping and monitoring a compound slow moving rock slide [Articolo su rivista]
Corsini, Alessandro; Castagnetti, Cristina; Bertacchini, Eleonora; Rivola, Riccardo; Ronchetti, Francesco; Capra, Alessandro

A slow moving compound rock slide located in the northern Apennines of Italy was mapped and monitored through the integration of Airborne Laser Scanning (ALS), multi-temporal long-range Terrestrial Laser Scanning (TLS), and Automated Total Station (ATS) measurements. Landslide features were mapped using a High Resolution Digital Terrain Model (HR-DTM) obtained by merging ALS and TLS data in an Iterative Closest Point (ICP) procedure. Slope movements in the order of centimeters to a few decimeters were quantified with Differential TLS (D-TLS) based on a Surface Matching approach and supported by ATS data to define stable reference surfaces. The integrated approach allowed mapping of the composite geomorphic features of the rock slide under examination, revealing its complex dynamic nature and further proving that laser scanning is a versatile and widely applicable tool for slope process analysis

2013 - Kinematics of active earthflows revealed by Digital Image Correlation and DEM of Difference techniques applied to multi-temporal LiDAR data [Articolo su rivista]
Daehne, Alexander; Corsini, Alessandro

Earthflow-type landslides are persistent natural hazards having deep socio-economic and environmental consequences. They have significantly contributed to the geomorphic evolution of mountainous slopes in Europe since the Late Glacial. An understanding of their complex kinematics is crucial to better constrain the processes governing their occurrence and mobility. In this work, with reference of a large flow-type landslide locatedin the northern Apennines of Italy, we explored the possibility to quantify displacement vectors on a spatially distributed basis and to quantify volumetric transfer at the slope scale with the application of digital image correlation (DIC) and digital elevation model difference (DEMoD) techniques to multitemporal airborne LiDAR surveys of 2006, 2007 and 2009. DIC was applied to greyscale slope gradient maps retrieved after precise co-registration of LiDAR surveys, and allowed for a reconstruction and quantification of movement patterns over various sectors of the landslide (up to 60 m in the upper and main track of the landslide and up to about 27 m at the landslide toe). DEMoD analysis revealed significant mass transfer from the source to the tracks and toe zone, with the upper flow tracks acting as temporal storage of large amounts of material. The mass balance indicated that during reactivation events significant amounts of debris were actually eroded away from river erosion of the advancing toe. The combined analysis of results allowed discussing governing processes such as the transition from slide to flow, the influence of underlying topography on earthflow mobility and the role of undrained loading as a mechanism of toe zone reactivation. In conclusion, the successful application of DIC and DEMoD to the case study evidenced the added value of high-resolution DEMs in the analysis earthflows kinematics toward a better understanding of their role in the geomorphic evolution of slopes.

2013 - Landslide displacement monitoring from multi-temporal terrestrial digital images: case of the Valoria landslide site [Relazione in Atti di Convegno]
M., Motta; F., Gabrieli; Corsini, Alessandro; V., Manzi; Ronchetti, Francesco; S., Cola

This work presents a low-cost method to measure the displacement of some points on the landslide surface. The method uses a sequence of terrestrial digital images. The Image Acquisition System (IAS) consists in a remote connected DSLR camera and controlled by software. The camera is fixed on a stable pillar, inside a transparent box and it periodically takes the pictures of the landslide. In order to rectify the image and to correct the little natural displacement of the image plane with respect to the landslide some fixed reference points are selected in the images. Moreover, some “well recognizable” optical targets are used in order to evaluate the displacement field. The image sequence is analyzed with a home-made digital image correlation code. The colour and size of the optical targets were evaluated in order to get the maximum accuracy of measurements and to improve the auto-matching function between the images. Taking pictures with bracketing function was proved to help the target searching phase for different weather conditions. The possibilities of the method are evaluated with reference to a sequence of images taken at the Valoria landslide site (Northern Apennines, Italy).

2013 - Large-scale slope instability affecting SS63 near the Cerreto Pass (northern Apennines, Italy) [Relazione in Atti di Convegno]
Corsini, Alessandro; Ronchetti, Francesco; Bertacchini, Eleonora; Bonacini, Francesco; Calicetti, P; Capra, Alessandro; Castagnetti, Cristina; Piantelli, E; Caputo, G; Truffelli, G.

National Road SS63 is endangered by large scale slope instability phenomena few km north of the Cerreto Pass (northern Apennines, Italy). At the Col Piagneto slope, SS63 was closed two times in the past 50 years after landslide events. In 1974, the collapse of portion of a rock slide triggered a debris slide that buried more than 50 m of the road track. In 2008, the reactivation of an earth slide in eastern portion of the slope damaged about 400 m of the “new” track built to by-pass the 1974 risk area. In order to evaluate if it is worthwhile keeping the old track open to traffic, or it is maybe better to repair the new track a comprehensive study was financed by Emilia Romagna Region. Research methods included: high resolution DEM, landslides mapping, continuous displacement and groundwater monitoring. Results allowed to assess different semi-quantitative risk scenario for the road structures or vehicles.

2013 - Multi-sensors integrated system for landslide monitoring: critical issues in system setup and data management [Articolo su rivista]
Castagnetti, Cristina; Bertacchini, Eleonora; Corsini, Alessandro; Capra, Alessandro

This paper discusses critical issues related to the reliability of topographic monitoring systems such as ATS (Automated Total Stations), GNSS (Global Navigation Satellite System) and Ground Based InSAR focusing the attention on controlling the stability of networks infrastructure, which have influence on data correction procedures but are often taken for granted, and on integrating results in GIS (Geographic Information System), under a common reference framework and with respect to open-access ancillary data. The novelty of the paper lies in the demonstration of the efficiency obtained by a proper implementation of the system. Discussion makes reference to an active landslide by using ATS, GNSS and Ground Based InSAR in continuous and periodic mode

2013 - Origin of the lake: the hypothesis of a giant landslide [Capitolo/Saggio]
Corsini, Alessandro

The chapter deals with the hypothesis of an ancient landslide as geomorphic factor that dammed the valley and, consequently, the formation of the Lake Paruhuay. Evidences from aerial images, maps and field surveys are provided

2013 - Rapid assessment of landslide activity in Emilia Romagna using GB‐InSAR short surveys [Relazione in Atti di Convegno]
Corsini, Alessandro; Berti, M.; Monni, A.; Pizziolo, M.; Bonacini, Francesco; Cervi, Federico; Ciccarese, G.; Ronchetti, Francesco; Bertacchini, Eleonora; Capra, Alessandro; Gallucci, A.; Generali, M.; Gozza, G.; Pancioli, V.; Pignone, S.; Truffelli, G.

Rapid assessment of landslide activity is important in case of adverse climatic conditions leading to civil protection’s alerts that require increased surveillance of risk areas. GB-InSAR is nowadays becoming a consolidated near-sensing monitoring technique for slope movements. It can be installed rapidly and it can rapidly provide results in the form of displacement maps. However, it has never been thoroughly tested in radar-hostile conditions such as these posed by large-scale earth slides – earth flows covered by a canopy of trees bushes and meadows, that are the typical landslides in Emilia Romagna Apennine. As sparse small villages, buildings, roads and other lifelines are often built on these landslide bodies, they are of particular concern for civil protection, especially during prolonged rainfall periods that determine attention/alerting conditions. To test the possibility to achieve improved surveillance capability in case of attention needed, a series of GB-InSAR spot campaigns lasting from a week to a month, was carried out in 2010-11 in several landslides of Emilia Romagna Apennine using a commercial interferometric radar. The aim was to evaluate the performance of the technique for rapid assessment of landslide activity, even in case of partly vegetated soil coverage conditions. The paper deals with the results obtained in 3 out of the 11 monitored sites.

2013 - Retrieving high resolution deformation patterns of slow moving landslides by COSMO-SkyMed SAR data: a sustainable long term monitoring system using artificial reflectors [Abstract in Atti di Convegno]
Iasio, Christian; Mulas, Marco; Corsini, Alessandro

Retrieving high resolution deformation patterns of slow moving landslides by COSMO-SkyMed SAR data: a sustainable long term monitoring system using artificial reflectors

2013 - Seismic monitoring of soft-rock landslides: Super-Sauze and Valoria landslides case studies [Articolo su rivista]
Tonnellier, A.; Helmstetter, A.; Malet, J. P.; Schmittbuhl, J.; Corsini, Alessandro; Joswig, M.

Thiswork focuses on the characterization of seismic sources observed in clay–shale landslides. Two landslides are considered: Super-Sauze (France) and Valoria (Italy). The two landslides are developed in reworked clay–shales but differ in terms of dimensions and displacement rates. Thousands of seismic signals have been identified by a small seismic array in spite of the high-seismic attenuation of the material. Several detection methods are tested. A semiautomatic detection method is validated by the comparison with a manual detection. Seismic signals are classified in three groups based on the frequency content, the apparent velocity and the differentiation of P and S waves. It is supposed that the first group of seismic signals is associated to shearing or fracture events within the landslide bodies, while the second group may correspond to rockfalls or debris flows. A last group corresponds to external earthquakes. Seismic sources are located with an automatic beam-forming location method. Sources are clustered in several parts of the landslide in agreement with geomorphological observations. We found that the rate of rockfall and fracture events increases after periods of heavy rainfall or snowmelt. The rate of microseismicity and rockfall activity is also positively correlated with landslide displacement rates. External earthquakes did not influence the microseismic activity or the landslide movement, probably because the earthquake ground motion was too weak to trigger landslide events during the observation periods.

2012 - A new approach for slope instability characterization: spatio-temporal analysis of SAR based time series applied to the corvara in Badia landslide test-case (Dolomites, Italy) [Relazione in Atti di Convegno]
Mulas, Marco; Petitta, Marcello; Branzanti, Mara; Benedetti, Elisa; Corsini, Alessandro; Iasio, Christian

The aim of this study is to discern and estimate the influence of different forcing factors acting on instability phases of a slow alpine earthslide-earthflow. To reach this scope, the deformation signals of displacement rates measured by Persistent Scatterers Interferometry (PSI) have been decomposed and analyzed taking in mind the dynamics of the different sectors included in the mass movement already known by previous studies.

2012 - Cosmo Skymed High Frequency - High Resolution Monitoring Of An Alpine Slow Landslide, Corvara In Badia, Northern Italy [Relazione in Atti di Convegno]
Iasio, C.; Novali, F.; Corsini, Alessandro; Mulas, Marco; Branzanti, M.; Benedetti, E.; Giannico, C.; Tamburini, A.; Mair, V.

Located in the Alta Badia Valley, a famous tourist area in the Dolomites of northern Italy, the active Corvara earthslideearthflow causes damages to critical road infrastructures, as well as ski and other recreational facilities and power lines. The high spatial resolution and the short frequency of revisit time of COSMO-SkyMed system (CSK®), open new opportunities for SAR-based monitoring systems dedicated to natural risks management. The ASI AO funded project “LAWINA” takes advantage from these distinctive features together with non-conventional reflectors, in order to monitor and assess the hazard of such a phenomenon by means of PSI techniques. The particular working context and the complete processing workflow for this specific application, offer opportunity to highlight strengths and weak points of classical approach to PSI and to provides suggestions for an effective use of experimented corners.

2012 - Critical aspects of an integrated monitoring system for landslides risk management: strategies for a reliable approach [Abstract in Atti di Convegno]
Castagnetti, C.; Bertacchini, E.; Capra, A.; Corsini, A.

2012 - GB-InSAR survey of the Valoria earthflow during the 2009 reactivation (Northern Apennines, Italy) [Relazione in Atti di Convegno]
Corsini, Alessandro; Daehne, Alexander; Bertacchini, Eleonora

A GB-InSAR is a valuable monitoring system for unstable slope. When LoSs of pixel coherence is low, it is capable to measure movements up to m/day in a spatial continuous way. These meas- urements can then integrated with spatially discrete monitoring data obtained for example by automated topographic survey stations. In this paper, the GB-InSAR technique was tested in a 3 day measuring campaign at the Valoria earth flow during a reactivation event in 2009. Results were compared and validated with measurements of a continuous topographic monitoring system that consists of a total station. For this purpose, total station data were projected into line of sight displacements concurring with the displacement direction of the GB-InSAR survey. The test proved that even in difficult conditions, i.e. high water content in the ground and significant displacement, the radar is capable of returning robust results that are comparable, and potentially complementary to that of the total station.

2012 - Origin and assessment of deep groundwater inflow in the Ca' Lita landslide using hydrochemistry and in situ monitoring [Articolo su rivista]
Cervi, Federico; Ronchetti, Francesco; Martinelli, G.; Bogaard, T. A.; Corsini, Alessandro

Changes in soil water content, groundwater flow and a rise in pore water pressure are well-known causal or triggering factors for hillslope instability. Rainfall and snowmelt are generally assumed as the main sources of groundwater recharge. This assumption neglects the role of deep water inflow in highly tectonized areas, a factor that can influence long-term pore-pressure regimes and play a role on local slope instability. This paper aims to assess the origin of groundwater in the Ca' Lita landslide (northern Italian Apennines) and to qualify and quantify the aliquot attributable to deep water inflow. The research is essentially based on in situ monitoring and hydrochemical analyses. It involved 5 yr of continuous monitoring of groundwater levels, electrical conductivity and temperature and with groundwater sampling followed by determination of major ions (Na+, K+, Mg2+, Ca2+, Cl−, HCO3−, SO42−), tracers (such as Btot and Sr2+), and isotopes (δ18O, δ2H and 3H). Leaching experiments on soil samples, hydrochemical modelling and water recharge estimation were also carried out. Results show that the groundwater balance in the Ca' Lita landslide must take into account an inflow of deep and highly mineralised Na-SO4 water (more than 9500 μS cm−1) with non-negligible amounts of Cl− (up to 800 mg l−1). The chemical and isotopic fingerprint of this water points to oilfield water hosted at large depths in the Apennine chain and that uprises through a regional fault line crossing the landslide area. It recharges the aquifer hosted in the bedrock underlying the sliding surface (at a rate of about 49 000–85 700 m3 yr−1) and it also partly recharges the landslide body. In both the aquifers, the hydrochemical imprint of deep water mixed with rainfall and snowmelt water was observed. This indicates a probable influence of deep water inflow on the mobility of the Ca' Lita landslide, a finding that could be applicable to other large landslides occurring in highly tectonized areas in the northern Apennines or in other mountain chains. The paper demonstrates that hydrochemistry should, therefore, be considered as a valuable investigation method to define hydrogeological limits and the groundwater sources in hillslope and to assess groundwater flow patterns in deep-seated landslides

2012 - Overview of 2001–08 GPS monitoring at the Corvara landslide and perspectives from 2010–11 use of HR X-band SAR (Dolomites, Italy) [Relazione in Atti di Convegno]
Corsini, Alessandro; Iasio, C.; Mair, V.

The Corvara landslide is a large active earthslide–earthflow in the Alta Badia Valley, Dolomites (South Tyrol, northern Italy). Over the last decades, the valley became renowned as a winter ski resort and an important area for summer tourism. Due to its slow but steady displacement, the landslide damages the national road 244, which connects the Alta Badia Valley to the Campolongo Pass, as well as lifelines, ski lifts and water pipes for snow production. The landslide is being investigated since 1996 and discontinuously monitored by means of GPS surveys from 2001, in order to assess geomorphic hazard and to establish possible mitigation measures. Recently, PS interferometry (based on 2010–11 high resolution X-band SAR data from the Cosmo SkyMed mission) has been tested using corner reflectors installed at GPS benchmarks points, allowing cross-validation and monitoring system integration. This paper provides an overview of GPS results for the period 2001–2008, discusses evidence on the seasonal behavior of different landslide sectors, presents recently obtained PS results, and highlights the positive perspectives opened by high-frequency SAR datasets in capturing slope processes more effectively than by means of periodic GPS only.

2012 - Spatio-temporal analysis of SAR based time series for slope instability characterization : the Corvara in Badia landslide ( Dolomites , Italy ) [Abstract in Atti di Convegno]
Mulas, Marco; Petitta, Marcello; Branzanti, Mara; Benedetti, Elisa; Corsini, Alessandro; Iasio, Christian

The aim of this study is to estimate the influence of different forcing factors acting on instability phases of a slow alpine earthslide-earthflow, by means of the characteristics of decomposed deformations signals derived by displacement rates measured in its different sectors. In this work we analyze a slow landslide located ESE from Corvara in Badia, a famous tourist area in the Dolomites (NE Italy). Road, infrastructure, ski and other recreational facilities, isolated buildings close to the town of Corvara and finally an artificial reservoir for snow production are threatened and occasionally damaged by this mass movement. It flows from 2000m s.l. to 1500m s.l. where a paleo-landslide deposit is partially covered and re-activated. In the last 10 years the Province of Bolzano carried out discontinuous GPS surveys between 5 and 1 times per year to define the landslide’s level of hazard. The landslide volume is resulted to be 30Mm3, xtending downslope for approx. 3km, with displacement rates between few centimeters and slightly less than 10m per year. To analyze this area we used data from active radar sensors (SAR – Synthetic perture Radar). The SAR-based dataset consists in high resolution X-band SAR data from the Cosmo SkyMed (CSK) mission acquired every 8 days from August 2010 to September 2011. Part of the 38 CSK scenes contain the back-scattering signal from 17 artificial reflectors (AR) installed along the AOI and partially on existing GPS benchmarks for data validation and integration. The ARs back scattering signal has been elaborated in order to track their displacement from August 2010 to September 2011, in the lower zone of the landslide, as well as from March 2011 to September 2011 in the higher part, excluding the period when the snow was covering the surface. The signals have been analyzed with Fourier and wavelet methods to identify the different frequencies and nature of the components. T and Mann-Kendall tests have been used to assess the presence of trends. Fits with exponential functions of the de-trended and de-seasonalized signal have been performed to identify the presence of dissipating deformations. We observed that the signal of velocity and acceleration is characterized by the coexistence of different factors: first, periodic signals associated to seasonal and gravitational kinematic behavior; second, decay effects due to instability events. Moreover, using different points is possible to observe the signal propagation both in time and space. This analysis allow us to determine the spatio-temporal scale of different forcing events and their effect on the total landslide area. Finally, this study represent a new approach for identify the spatio-temporal nature of different factors in the evolution of the landslide for setting-up a system of conscious prediction of aintenance tasks of he exposed structures. The use of the SAR data demonstrated to be an innovative tool for high temporal resolution surveys with a big amount of points that in comparison with GPS surveys results to be conomically convenient in wide AOI.

2011 - Atmospheric corrections for topographic monitoring systems in landslides. [Relazione in Atti di Convegno]
Bertacchini, Eleonora; Capra, Alessandro; Castagnetti, Cristina; Corsini, Alessandro

SUMMARYNew automated “long range” total stations are actually available for monitoring landslides, dams, structures etc. The use of total station is consolidate within some hundred meters of distance and with a supervisor. But the long range (up to 3 km) measurements are not still completely investigated in operating condition. When the accuracy and the precision required are important, seems to be necessary to investigate the atmosphere influence on distance measurements. The research deals with the study of a landslide topographic monitoring system: the Collagna Landslide (Reggio Emilia, Italy) monitoring system. It consists of an automated long range total station acquiring about 36 prisms ,every 4 hours, since 2009. The idea was to test how atmospheric corrections could improve the measurements precision and accuracy to exploit the system capabilities. Some tests on the total station EDM (Electronic Distance Measuring) system are presented in operating conditions. Particularly attention was paid to the long distances dependence on atmospheric conditions (temperature, pressure and relative humidity). Two kinds of corrections were applied, that of the instrument and one of the literature. Some differences were found on atmospheric corrections calculated with the two different methods. But it seems that atmospheric corrections can really improve the final result accuracy.

2011 - Explanatory notes of the Geomorphological map of the Alta Badia valley (Dolomites, Italy) [Articolo su rivista]
Panizza, Mario; Corsini, Alessandro; Ghinoi, Alessandro; Marchetti, Mauro; A. PASUTO, A.; Soldati, Mauro

This paper shows the geomorphological aspects of the Alta Badia valley (Autonomous Province of Bolzano, northern Italy), located in one of the best known areas of the Italian Dolomites, between the passes of Gardena, Campolongo and Valparola-Falzarego. The paper is also aiming at illustrating the annexed Geomorphological Map of the Alta Badia valley (Dolomites, Italy), at 1:20,000 scale.The present morphological features of the Alta Badia valley is the result of a complex interaction between geological structure and modelling processes that have mainly been active since the Last Glacial Maximum (LGM). Stratigraphy and structure controlled the formation of sub-horizontal dolomitic plateaus, flanked by sub-vertical slopes that are linked to less inclined ones - where softer materials mainly outcrop - by broad scree slopes and talus cones.Landforms in the area are largely related to mass movements that have progressively remodelled the main valleys during the Holocene, partly masking the older traces of glacial origin. Landslides - that took place after the progressive glacier retreat - showed an intense period of activity at the end of the Lateglacial, followed by alternated clustering during the Holocene, as witnessed by several radiometric datings. Slope processes have gradually become the main geomorphological feature in the valley. The slopes are, at present, characterized by the presence of extensive scree slopes and talus cones, debris flow accumulations and different types of landslides. Sometimes, landslide bodies dammed the valley bottoms forming lakes. This is the case of the plain of Corvara in Badia that is made up of alluvial and lacustrine deposits accumulated as a consequence of the repeated damming of the valley since the early Holocene.The traces of the LGM consist of scattered and small moraine deposits on plateaus as well as of broader outcrops along the slopes, where they have largely been mobilized by subsequent mass movements. On the other hand, glacial landforms shaped during the Lateglacial are mainly located in the lowest part of slopes and, occasionally, along the valley floors, especially in the centre-eastern part of the study area.Recently, the intense urbanization and the development of the ski tourism, on which the economy of the valley is based, have been modifying the landscape with ever growing intensity.

2011 - Integrating LIDAR and terrestrial laser scanning for a full and reliable description of landslides geomorphology [Abstract in Atti di Convegno]
Castagnetti, C.; Bertacchini, E.; Capra, A.; Dubbini, M.; Rivola, R.; Corsini, A.

2011 - Landslide Monitoring with Sensor Networks: Experiences and Lessons Learnt from a Real-world Deployment [Articolo su rivista]
Rosi, Alberto; M., Berti; Bicocchi, Nicola; Castelli, Gabriella; Mamei, Marco; Corsini, Alessandro; Zambonelli, Franco

Wireless sensor networks have the potentials to be a very useful technology for fine-grained monitoring in remote and hostile environments. This paper reports on the implementation and deployment of a system for landslide monitoring in the Northern Italy Apennines, and analyzes the positive results we have achieved with it. Yet, the paper also critically analyzes the problems and the inherent limitations/difficulties we had to face in developing and deploying such a system, challenging many of the “big claims” that are often heard around wireless sensor networks.

2011 - Monitor II: new methods for linking hazard mapping and contingency planning [Monografia/Trattato scientifico]
Kollarits, S.; Leber, D.; Corsini, Alessandro; Papez, J.; Preseren, T.; Schnetzer, I.; Schwingshandl, A.; Kreutzer, S.; Plunger, K.; Stefani, M.

The present brochure deals with the state of the art of hazard mapping and contingency planning and provides a general framework for adaptations and improvements. This brochure is intended to provide information to • experts of hazard mapping and natural hazards • authorities competent for disaster management, esp. contingency planning. The goal of the brochure is to provide these groups with a better understanding of the tasks and needs of each other. The long term goal is to improve communication between these domain expert groups. As state-of-the-art analysis, this brochure reflects the discussion arising from the problems and issues encountered by the participating project partners in their testbeds.

2011 - Rilievi integrati per il monitoraggio e la gestione dell’instabilità dei versanti [Capitolo/Saggio]
Bertacchini, Eleonora; Castagnetti, Cristina; Capra, Alessandro; Rivola, Riccardo; Corsini, Alessandro

Nowadays civil protection and environment safeguard are of topical interest. The hydro-geological instability and landslides as well, in fact, are serious problems that unfortunately characterize our whole country. The consequences are sometimes severe and there is more to deal with such as emergencies and disasters directly affecting the population. Geomatics, in this sense, offers a wide variety of methodologies and technologies, both well-established and well-advanced, functioning as an important support to the control and monitoring of territory. Key studies concern the phenomenon itself, risk prevention and emergency management . Concerning that, the present paper presents the design and implementation of an integrated system based on topographical and geotechnical instrumentation with the purpose to continuously monitor a landslide. Two case studies will be presented: they are both located in the Apennines of Emilia-Romagna Region. The system consists of a robotic total station located in a geologically stable area together with a GNSS (Global Navigation Satellite System) receiver which acts as a permanent master station. The robotic total station regularly runs several times a day repeating the same action, which consists on measuring a series of prisms positioned both inside and outside of the landslide body. A two-directions inclinometer monitors the stability of the monument in real-time mode. An additional GNSS, acting as a rover receiver, has been placed at the edge of the landslide to assess over time the possible extension of the phenomenon (continuous monitoring). The monitoring system, operating in continuous mode, is remotely managed; this allows a constant control on displacements and ensures a rapid and effective action in case of emergency . Together with the topographic instruments, some extensometers, inclinometers and piezometers were installed with the aim to study the deformation mechanism of the investigated phenomenon. LIDAR (Light Detection And Ranging) surveys were carried out to obtain the DTM (Digital Terrain Model) and high accuracy orthophotos of the area. Periodical flights were performed to detect and study the subsequent reactivations. The present research aims to present some phenomena, which are similar to many others in the country, with the aim of strengthening the role, the importance and the usefulness of Geomatics in the monitoring of the territory.

2011 - Sperimentazione di corner per banda X nel monitoraggio di colate di terra lente con COSMO SkyMed [Relazione in Atti di Convegno]
Iasio, C.; Corsini, A.; Mair, V.; Schneiderbauer, S.; Tamburini, A.

2011 - Surveillance of landslides risk areas with ground-based interferometric SAR for Civil protection in Emilia Romagna (Italy). [Relazione in Atti di Convegno]
Corsini, Alessandro; F., Cervi; G., Ciccarese; J. P., Iannacone; Ronchetti, Francesco; Bertacchini, Eleonora; Capra, Alessandro; M., Berti; E., Brancaleoni; P., Mora; V., Pancioli; A., Gallucci; G., Gozza; A., Monni; M., Generali; M., Pizziolo; G., Caputo; G., Truffelli; V., Manzi; F., Ghiselli; M., Guida; G., Minardi; C. C., Lucente; A., Bernardi; A., Benini

Experimental applications of Groune Based SAR to landslides movement/deformation control. The objective was to verify yìthe possibility to apply GBsAR techniques for civil protection activities in Emilia Romagna region relatively to the different types of landslides.

2010 - Applications of a numerical model for slow moving landslides to the Valoria landslide in the Italian Apennines, and the Super Sauze mudslide in the French Alps [Relazione in Atti di Convegno]
Daehne, Alexander; Corsini, Alessandro; Travelletti, J.; Spickermann, A.; Malet, J. P.; Van Asch, T. h. W. J.; Bégueria Portuguès, S.

ISBN 2-95183317-1-5This research demonstrates the applicationof the dynamic SLOWMOVE model onthe Valoria case study located in the northern Apennines (Italy) and the Super-Sauze landslide in the southwestern Alps (France). The SLOWMOVE model is based on the Navier-Stokes equations. The landslide is modeled as a one-phase material with homogeneous and constant rheological properties. The slow movements of landlside materials allow for the cancellation of the inertia term from the momentum equation. At the Valoria case study site a 3.5 km long earth slide/flow with materials comprised of disaggregated Flysch, Marl and Clay-stones resumed activity in 2001 after a suspended phase. The landslide is characterized as earth slides in the upper slope, and as earth flows in the main track following complete disaggregation of the materials in the source areas. During reactivations, the earth flows can reach velocities up to 10 m·h-1. Characteristic for the landslide activity are repeated acceleration events ascribed to seasonal climatic inputs. Through continuous activity since 2001, more than 15 million cubic meters of material have been transferred down-slope. The Su-per-Sauze landslide is triggered in Callovo-Oxfordian black marls and is composed of a silty-sand matrix mixed with moraine debris. It extends over a horizontal distance of 850 m with an average slope of 25° impli-cating a volume of 560,000 m³. The complex paleo-topography covered by the landslide is made by succes-sions of crests and gullies which play an essential role in the mudslide behavior by creating sections with dis-tinct kinematical, mechanical and hydrological characteristics. The mudslide kinematics is characterized by a spatially heterogeneous displacement field with velocities ranging from 0.01 to 0.40 m day-1. For the Valoria landslide, the performance of the 1D approach of SLOWMOVE was analyzed on a representative landslide cross-section from the main track zone down to the toe zone. Multi-temporal Lidar surveys in conjunction with a large set of surface displacement data obtained from continuous monitoring since March 2008 was used to calibrate and evaluate the SLOWMOVE model. The model is capable to simulate realistic velocities and displacements but failed to achieve an accurate topographic reconstruction of the morphologic changes between 2003 and 2007. For the Super Sauze mudslide, the 2.5 D approach is used to simulate the heteroge-neous displacement field of the mudslide. The performance of the model is evaluated on multi-temporal and spatially distributed datasets of landslide displacements for the period of summer 2009

2010 - Comparing predictive capability of statistic and deterministic methods for landslide susceptibility mapping: a case study in the northern Appennines (Reggio Emilia Province, Italy) [Articolo su rivista]
Cervi, Federico; Borgatti, Lisa; M., Berti; Ronchetti, Francesco; F., Manenti; Corsini, Alessandro

Statistical and deterministic methods are widely used ingeographic information system based landslide susceptibility mapping.This paper compares the predictive capability of three differentmodels, namely the Weight of Evidence, the Fuzzy Logic andSHALSTAB, for producing shallow earth slide susceptibility maps, to be included as informative layers in land use planning at a local level.The test site is an area of about 450 km2 in the northern Apennines ofItaly where, in April 2004, rainfall combined with snowmelt triggeredhundreds of shallow earth slides that damaged roads and otherinfrastructure. An inventory of the landslides triggered by the eventwas obtained from interpretation of aerial photos dating back to May2004. The pre-existence ofmapped landslides was then checked usingearlier aerial photo coverage.All the predictivemodelswere run on thesame set of geo-environmental causal factors: soil type, soil thickness,land cover, possibility of deep drainage through the bedrock, slopeangle, and upslope contributing area. Model performance wasassessed using a threshold-independent approach (the ROC plot).Results show that global accuracy is as high as 0.77 for both statisticalmodels, while it is only 0.56 for SHALSTAB. Besides the limited qualityof input data over large areas, the relatively poorer performance of thedeterministic model maybe also due to the simplified assumptionsbehind the hydrological component (steady-state slope parallel flow),which can be considered unsuitable for describing the hydrologicbehavior of clay slopes, that are widespread in the study area.

2010 - Environmental Monitoring and Task-Driven Computing [Articolo su rivista]
Rosi, Alberto; M., Berti; Bicocchi, Nicola; Castelli, Gabriella; Corsini, Alessandro; Mamei, Marco; Zambonelli, Franco; E. T. A., L.

We report on our early experience in landslide monitoring with sensor networks.

2010 - Hydro-mechanical features of landslide reactivation in weak clayey rocks [Articolo su rivista]
Ronchetti, Francesco; L., Borgatti; Cervi, Federico; Corsini, Alessandro

In the northern Apennines, four representativelarge and deep seated landslides affecting weak rockmasses have been studied before, during and after reactivationevents. Semi-continuous and continuous monitoringin the 2004–2006 period included the dormancy, reactivationand suspension phases, allowing some comments tobe put forward as regards the hydro-mechanical conditionsthat drive the reactivations. The data have highlighted theinteractions between groundwater and displacement ratesin different sections of the slope.

2010 - Innovative integrated airborne and wireless systems for landslide monitoring [Relazione in Atti di Convegno]
P., Sterzai; M., Vellico; M., Berti; F., Coren; Corsini, Alessandro; Rosi, Alberto; P., Mora; Zambonelli, Franco

Landslides are a widespread phenomenon over the Italian territory and economical losses due to this hazard are impressive (an average of 2 billion of euros per year in the last 50 years). In the framework of the WISELAND research project (Integrated Airborne and Wireless Sensor Network systems for Landslide Monitoring) funded by the Italian Government, we are testing new monitoring devices devoted to control large landslides at different degrees of activity. Integrated monitoring tools with a strong innovative character are being explored, in particular ground-based wireless sensor networks combined with airborne laser-scanning and hyperspectral surveys.A wireless sensor network (WSN) consists of a set of low cost micro-computers capable to measure physical parameters and to communicate between them. Such a technique allows landslides remote monitoring, measuring spatially distributed parameters and recognizing deformation patterns. Ground-based sensor networks can be effectively integrated with grid-based data measured by the use of airborne techniques. The Light Detection and Ranging (Lidar) technology is used primarily to densely map wide areas, even in presence of a thick vegetation coverage, to retrieve high resolution Digital Terrain Models (DTMs); DTMs are fundamental in monitoring and describing landslide movements. Hyperspectral sensors are capable to measure parameters such as soil moisture content, vegetation coverage and surface roughness, that can be correlated with slope movements.In the first year of the project we tested and validated these monitoring tools on two large earthflows, which are representative of the widespread slope instability in the Northern Apennine: the Silla landslide (Bologna Province, Italy) and the Valoria landslide (Modena Province, Italy). Although characterised by different geological settings and evolution stages, both landslides are associated to a high degree of risk because of the presence of vulnerable elements and their tendency to periodic and abrupt reactivations.Periodic airborne surveys were performed in Valoria site in different periods, in order to monitor the surface displacement of the slopes. Multitemporal Lidar DTMs allowed the calculation of a differential surface, therefore highlighting absolute height variations and recognizing the main landslide components. Hyperspectral data helped in the landslide characterization; for instance the analysis of PCA components are also correlated with results coming from DTM analysis and this has been evidenced to be a proper system to identify depletion and accumulation zones.A prototype wireless sensor network was installed at Silla landslide in July 2009. The network consists of four nodes (located in the upper part of the landslide) configured with static routing table which forward packets (one data every 15 minutes) to a master node connected to a laptop. Parallel to this test, a new node hardware platform, more shaped for low power – high range data transmission in outdoor conditions has been developed and it is now ready to be deployed in the field.

2010 - Integrated displacement and activity analysis at the Valoria landslide (Italian Apennines) through automated topographic monitoring, image correlation velocimetry and surface roughness computation [Relazione in Atti di Convegno]
Daehne, Alexander; Corsini, Alessandro; Ronchetti, Francesco

ISBN 2-95183317-1-5At the Valoria landslide located in the Italian Apennines, surface monitoring data acquired by an automated total station were analyzed. The system provided short-term information on the behavior of the material during crisis and the duration of reactivations. Long-term displacements and morphometric properties were studied using a geographic information system (GIS). Results from monitoring show a strong correlation between rainfall related triggering of mass wasting in the crown zone and subsequent downslope reactiva-tions. We found that crown-to-toe zone reactivations generally occur within only 6 weeks. Further findings indicate that earth slide materials in the head zone fail almost instantaneous conversely to earth flow materials in the track channel. The findings are complemented by a digital image correlation analysis of multi temporal, high-resolution digital elevation models (DEM) acquired in 2006, 2007 and 2009. We utilized this technique to compute velocities and displacements of pixels in the DEMs between 2006 and 2009. It was found that both azimuth and magnitude of displacements could be reconstructed in for the crown zone, the main track channel and the landslide toe. The results from the image correlation compare well to displacements obtained from independent monitoring methods (GPS and interpreting of shaded reliefs maps). Based on the assump-tion that increased materials movements result in higher terrain roughness, we used LiDAR-derived to per-form a raster based roughness analysis. Different roughness calculation methods were applied to 0.5 m eleva-tion grids using different Kernel sizes. The performance of a supervised and an unsupervised approach was evaluated. Findings from the supervised approach showed that the difference between active and dormant landslides is evident in some cases but also that earth flows and dormant landslides tend to have a similar roughness patterns as stable areas. Results from the unsupervised approach demonstrated that landslide roughness is heterogeneous and that non-landslide areas may have a similar morphometric signature. In this study it was demonstrated that near- and remote sensing techniques are crucial, as well as complimentary in the analysis of landslide hazard. Applying both approaches can yield a more complete picture of the defor-mation history of landslides

2010 - Ipotesi sugli eventi distruttivi rilevati nell’abitato romano di Montegibbio [Capitolo/Saggio]
Borgatti, L.; Cervi, Federico; Corsini, Alessandro; Guandalini, F.; Ronchetti, Francesco; Pellegrini, M.

Presso la località il Poggio, circa 500 m a N del castello di Montegibbio, in Comune di Sassuolo (Provincia di Modena), la Soprintendenza per i Beni Archeologici dell’Emilia-Romagna ha portato alla luce i resti di una sequenza di insediamenti di età romana (da una villa urbano – rustica del I secolo a. C. sino ad un insediamento del VI secolo d. C.). Una parte delle strutture presentano evidenze di lesioni di rilevante entità, che possono aver portato alla distruzione e al successivo abbandono degli insediamenti stessi. L’edificio più antico rinvenuto negli scavi del 2008, sul quale si focalizza prevalentemente il nostro contributo, aveva un pavimento in opus signinum e un’elevazione in ciottoli e blocchi, talora debolmente arrotondati, e in laterizio. L’obbiettivo di questo lavoro è di indagare le possibili cause che possono avere provocato le deformazioni rinvenute nelle strutture e ricostruire la sequenza di eventi ambientali che hanno accompagnato la vita e l’abbandono dell’insediamento romano di Montegibbio. Le ipotesi di lavoro che sono state hanno la finalità di rispondere a due domande, ovvero: Quali tipologie di eventi possono essere stati responsabili delle deformazioni osservabili sulle strutture? Tali eventi possono essere tanto di origine naturale (dissesto per frana, terremoto, erosione s.l., creep, cedimento e consolidazione dei terreni di fondazione), tanto di origine antropica (cedimento strutturale, asportazioni successive di materiale dovute in particolare alle lavorazioni agricole); Quanti eventi si sono eventualmente susseguiti? Si tratta di un solo evento che ha lesionato tutte le strutture o si tratta di una serie di dissesti? E nel secondo caso, i dissesti sono tutti della stessa natura o di natura differente? Le problematiche esposte sono state affrontate con un approccio multidisciplinare, che vede l’integrazione di diverse discipline oltre all’Archeologia, tra cui la Geologia e la Geologia Applicata.

2010 - Lidar And Hyperspectral Data Integration For Landslide Monitoring: The Test Case Of Valoria Landslide [Articolo su rivista]
Sterzai, P.; Vellico, M.; Berti, M.; Coren, F.; Corsini, Alessandro; Rosi, Alberto; Mora, P.; Zambonelli, Franco; Ronchetti, Francesco

In the framework of the WISELAND project, funded by MIUR, we tested the integration between Lidar and hyperspectral methodologies in the Valoria landslide (Modena province, Italy), a high risk area with vulnerable elements, subjected to periodic and abrupt reactivations. Multitemporal Lidar Digital Terrain Models (DTMs) allowed the calculation of a differential surface, highlighting absolute height variations, recognizing the main landslide components and identifying depletion and accumulation zones. Hyperspectral data helped in the landslide terrain roughness characterization, performing the Principal Component Analysis (PCA) and correlating the results with Flatness and Organization geomorphometric parameters derived from Lidar DTM.

2010 - Utilizzo dei sistemi di telerilevamento per il monitoraggio di fenomeni franosi: il progetto WISELAND [Relazione in Atti di Convegno]
Vellico, M.; Sterzai, P.; Pietrapertosa, C.; Corsini, Alessandro; Ronchetti, Francesco; Berti, M.; Mora, P.; Coren, F.

I fenomeni franosi sono ampiamente diffusi in tutto il territorio italiano e sono responsabili di ingenti perdite economiche, stimate nell’ordine dei 2 miliardi di euro l’anno negli ultimi 50 anni. Lo scopo del progetto WISELAND, afferente al Programma di Ricerca Scientifica di Rilevante Interesse Nazionale (PRIN) 2007, finanziato dal Ministero dell’Università e della Ricerca (MIUR), è la creazione di un sistema integrato ed innovativo di sensori wireless ed airborne per il monitoraggio e il controllo di fenomeni franosi a cinematica lenta. La sperimentazione di tale sistema è stata condotta su una frana per scorrimento-colata, tipica dell’Appennino: la frana di Valoria, in provincia di Modena. Nel corso del 2009 e 2010 sono stati condotti diversi rilievi aerotrasportati con sensoristica Lidar e iperspettrale. I primi hanno consentito di ricostruire accurati Modelli Digitali del Terreno (DTM), dalla cui analisi si è stati in grado di caratterizzare le componenti principali di una frana. Inoltre, tramite un’analisi differenziale e geomorfometrica dei DTM (relativi a rilievi effettuati in passato mediante la stessa metodologia), si sono individuati e monitorati gli spostamenti avvenuti in un certo arco temporale. I rilievi iperspettrali hanno contributo anch’essi alla caratterizzazione dei fenomeni franosi; in particolare si è dimostrato che i risultati ottenuti dalla Principal Component Analysis (PCA) sono correlabili con la rugosità del terreno ed il dinamismo di frana e consentono di metterne chiaramente in risalto le zone di accumulo e deplezione. Oltre ai datasets telerilevati, si sono utilizzati dei dati provenienti da una rete sperimentale di sensori wireless (WSN) installata nell’ambito del progetto, che ha permesso di rilevare gli spostamenti differenziali della frana in modo efficace e poco costoso. L’utilizzo combinato della metodologia Lidar, iperspettrale e di reti asensori wireless (WSN) si è dimostrata, pertanto, un valido strumento in grado di monitorareperiodicamente un fenomeno franoso. La potenzialità dei risultati aumenta con l’interpretazionecongiunta dei datasets. Il monitoraggio con queste metedologie può essere inoltre facilmenteprogrammato sia temporalmente che spazialmente, e questo garantisce una specificitàdell’informazione attualmente non garantita da altre metodologie operative.

2009 - Analysis of the relationships between hydrogeological characteristics of mountain basins and low flow discharge: Regional-scale prediction of hydrological indexes in ungauged basins of the northern apennines [Relazione in Atti di Convegno]
Cervi, F.; Borgatti, L.; Corsini, A.; Bloschl, G.; Pellegrini, M.

In the last decade the north of Italy suffered a marked hydrologic deficit as a consequence of decreasing mean annual precipitation and increasing demand from industry and agriculture. Rivers that outflow from the northern Apennines display a highly variable discharge rate, mainly because of inherited hydro-geological factors such as the extensive presence of low permeability sedimentary rocks with low storage coefficient in the mountain catchments. The growing interest for a proper management of water courses, that has led to directives regulating the amount of minimum water that must permanently flow downstream from points of water diversions and yield, makes the prediction of hydrological indexes in ungauged basins located in the mountain areas of relevant practical importance, since it can support a sustainable planning of surface water management along the entire water course. The research has being aimed at developing a spatial analysis tool for regional-scale prediction of hydro-geological indexes in ungauged basins, that still represent the majority of cases in the upper catchment areas of the northern Apennines. This has been dealt with by linking statistical indexes of discharge calculated for gauged basins (Q95, Q355), obtained with five years of continuous daily data, to the results of spatial analysis methods (such as Weight of Evidence, Logistic Regression, Neural Networks), that allow the storage coefficient of different bedrock types to be relatively ranked using the spatial distribution of permanent groundwater springs as main supporting evidence. The paper summarises the main results obtained that were validated in three basis within the whole study area.

2009 - Carta geomorfologica dell’Alta Badia (Dolomiti, Italia). [Cartografia]
Panizza, Mario; Corsini, Alessandro; Ghinoi, A.; Marchetti, Mauro; Pasuto, A.; Soldati, Mauro

Carta geomorfologica a scala 1:20.000 dell'Alta Badia edita da: Litografia Artistica Cartografica (LAC) sui tipi topografici TABACCO

2009 - Continuous monitoring of active earth flow by means of an integrated GPS-automatic total station approach [Articolo su rivista]
Corsini, A.; Capra, A.; Bertacchini, E; Borgatti, L.; Borghi, A.; Cristina, C.; Cervi, F.; Daehne, A.; Dubb Ini, M.; Leuratti, E.; Manzi, V.; Pellegrini, M.; Ronchetti, F.; Bonanno, C.; Piantelli, E.

The research deals with the integration of surface displacement measurements obtained using geodetic and topographic instruments such as GPS, automatic total station and inclinometer sensor in a large-scale active earth flow. The landslide, located in the northern Apennine of Italy, damaged roads and endangered houses during a sequence of reactivations in 2001, 2005 and 2007. Monitoring has been performed by means of: an automatic total station, coupled with inclinometer sensor, measuring about 40 prisms located in the landslide to a maximum distance of 1.650 km; one double-frequency GPS receiver connects in streaming by wireless communication with 4 single-frequency GPS in side the flow. Until December 2007 the monitoring network was operated with periodic static surveyings followed by the data post-processing; while since March 2008 the total station system and GPS were automated in order to allow continuous data acquisition and near-real-time data processing. The monitoring network has been able to cope with displacement rates ranging from millimetres to metres per day, a performance not achieved by borehole systems operated in the slope, such as in-place inclinometers, that were damaged when displacements exceeded some decimetres. The data so far collected, integrated with geomorphic, geologic and borehole data, allowed the complex spatial and temporal pattern of slope movements to be tracked and the relationships between rainfall pattern and acceleration-deceleration phases to be highlighted.

2009 - Coupling geomorphic field observation and Lidar derivatives to map complex landslides [Relazione in Atti di Convegno]
Corsini, Alessandro; Cervi, Federico; Daehne, A.; Ronchetti, Francesco; Borgatti, L.

High resolution LiDAR DEMs from regional or site specific surveys were used to map complexlandslides such as deep-seated rockslides and earth slides-earth flows. Regional surveys DEMs wereused to produce shaded relief maps that allowed delimiting rock slide units and sub-units at the slope scale.Multitemporal site-specific survey DEMs were used in eath slides-earth flows case studies to derive roughnessmaps that allowed defining the curvature fingerprint of the most active parts of earth flows, and to derivedifferential elevation maps that allowed assessing depletion and accumulation areas occurring in the slope asa consequence of post-failure dynamics.

2009 - Estimating mass-wasting processes in active earth slides – earthflows with time-series of High-Resolution DEMs fromphotogrammetry and airborne LiDAR [Articolo su rivista]
Corsini, Alessandro; Borgatti, L.; Cervi, Federico; Daehne, Alexander; Ronchetti, Francesco; Sterzai, P.

This paper deals with the use of time-series ofHigh-Resolution Digital Elevation Models (HR DEMs) obtainedfrom photogrammetry and airborne LiDAR coupledwith aerial photos, to analyse the magnitude of recently reactivated large scale earth slides – earth flows located in thenorthern Apennines of Italy. The landslides underwent completereactivation between 2001 and 2006, causing civil protectionemergencies. With the final aim to support hazardassessment and the planning of mitigation measures, highresolution DEMs are used to identify, quantify and visualizedepletion and accumulation in the slope resulting from the reactivation of the mass movements. This information allowsto quantify mass wasting, i.e. the amount of landslide materialthat is wasted during reactivation events due to streamerosion along the slope and at its bottom, resulting in sedimentdischarge into the local fluvial system, and to assessthe total volumetric magnitude of the events. By quantifyingand visualising elevation changes at the slope scale, resultsare also a valuable support for the comprehension of geomorphological processes acting behind the evolution of theanalysed landslides.

2009 - Geotechnische Bewertung der Hangbewegung Corvara (Dolomiten, Italien) - Effizienz moglicher Sanierungsmasnahme [Relazione in Atti di Convegno]
Knabe, T.; Schädler, W.; Corsini, Alessandro; Mair, V.; Schanz, T.

In den Dolomiten sowie im nördlichen Apennin ist das Phänomen großflächiger Schuttströme besonders weit verbreitet. Schuttströme sind Massenbewegungen, die vorzugsweise im Hang- und Verwitterungsschutt ausgeprägter, tiefgründig verwitternder Wechsellagerungen mit mächtigen Tonstein- und Mergeleinschaltungen auftreten.Ein solcher Schuttstrom erstreckt sich nahe dem Dorf Corvara. Während der jährlichen saisonal bedingten Reaktivierungsphasen entstehen häufig Schäden an Infrastrukturen. Die ontinuierlichen Bewegungen des Schuttstroms von Corvara führen fast alljährlich zu Schäden an der Nationalstraße 244, sowie an Stromleitungen und Liftanlagen, die sich auf dem Areal der Hangbewegung befinden. Benachbarte Siedlungen sind potenziell durch sekundäreMassenbewegungen (v. a. Murgänge nach Aufstau des Hauptvorfluters) bedroht.Aus diesem Grund wurden durch die Universität Modena und den Consiglio Nazionale delle Ricerche Padua (CNR-IRPI) mfangreiche Untersuchungen zur Geologie und Geomorphologie des gesamten Hanges durchgeführt. Ferner wurdeeine großflächig angelegte Monitoring kampagne umgesetzt, welche umfangreiche Messdaten, insbesondere Zeitreihen zu den Bewegungen sowohl an der Oberfläche als auch zum Bewegungsverlauf nach der Tiefe, zu Bergwasserspiegelständen und Porenwasserdruckschwankungen zusammen mit Klimadaten, erbrachte (Panizza et al. 2006).

2009 - Groundwater processes in a complex landslide, northern Apennines, Italy [Articolo su rivista]
Ronchetti, Francesco; L., Borgatti; Cervi, Federico; Gorgoni, Carlo; L., Piccinini; V., Vincenzi; Corsini, Alessandro

The hydrogeological characteristics of rototranslationalslides in flysch are complex, due to the inherentanisotropy and heterogeneity of rock masses and related deposits.The paper deals with the hydrogeological characterizationof a reactivated roto-translational slide affecting Cretaceousflysch rocks, located in the northern Apennines ofItaly. Continuous monitoring of groundwater levels, in-situpermeability and pumping tests, hydrochemical and physicalanalyses and Uranine tracers were the adopted prospectingmethods.In this research hydrological monitoring and investigationare summarized in order to define a hydrogeological conceptualmodel of the landslide source area. Results showed thattwo overlaying hydrogeological units exist at the slope scale:the first is unconfined, but highly compartmentalized, andhosted in the fractured and dismembered rock slide body.The second is confined and lays in the undisturbed flyschbelow the sliding surface. The groundwater level in theconfined hydrogeological unit is twenty meters higher thanthe groundwater level in the uppermost one. Moreover, thegroundwater chemistry characterization revealed a rising ofdeep fluids in the landslide area.

2009 - Hydrogeologic characterististics of roto-traslational slides in flysch [Relazione in Atti di Convegno]
Ronchetti, Francesco; Borgatti, L.; Cervi, Federico; Corsini, Alessandro; Gorgoni, Carlo; Piccinini, L.; Truffelli, G.; Vincenzi, V.

The hydrological characteristics of roto-translational slides in flysch are complex, due to the inherent anisotropy and heterogeneity of rock masses and related deposits. The paper deals with the hydrogeological characterization of a reactivated roto-translational slide affecting Cretaceous flysch rocks, located in the northern Apennines of Italy. Continuous monitoring of groundwater levels, in-situ permeability and pumping tests, hydrochemical analyses and uranine tracers were the adopted prospecting methods. Results showed that two overlaying aquifers exist at the slope scale: the first is unconfined, but highly compartmentalized, and hosted in the fractured and dismembered rock slide body. The second is confined and lays in the undisturbed flysch below the sliding surface. The latter is therefore a relevant factor for the instability of the slope. In this work, hydrologic monitoring and investigation are summarized, in order to support the analysis of landslide trigger mechanisms and to identify and design proper drainage system.

2009 - Hydrogeological characterization of roto-translational slides in flysch rock masses for mitigation proposes: The example of Ca'Lita landslide [Articolo su rivista]
Ronchetti, Francesco; L., Borgatti; F., Cervi; A., Gargini; C., Gorgoni; M., Pellegrini; L., Piccinini; G., Truffelli; V., Vincenzi; Corsini, Alessandro

The hydrogeological characteristics of rototranslational slides in flysch are complex, due to the inherent anisotropy and heterogeneity of rock masses and related deposits. The paper deals with the hydrogeological characterization of a reactivated roto-translational slide affecting Cretaceous flysch rocks, located in the northern Apennines of Italy. Continuous monitoring of groundwater levels, in-situ permeability and pumping tests, hydrochemical and physical analyses and Uranine tracers were the adopted prospecting methods. In this research hydrological monitoring and investigation are summarized in order to define a hydrogeological conceptual model of the landslide source area. Results showed that two overlaying hydrogeological units exist at the slope scale: the first is unconfined, but highly compartmentalized, and hosted in the fractured and dismembered rock slide body. The second is confined and lays in the undisturbed flysch below the sliding surface. The groundwater level in the confined hydrogeological unit is twenty meters higher than the groundwater level in the uppermost one. Moreover, the groundwater chemistry characterization revealed a rising of deep fluids in the landslide area.

2009 - Integrated Surveying System for Landslide Monitoring, Valoria Landslide (Appennines of Modena, Italy) [Relazione in Atti di Convegno]
Bertacchini, Eleonora; Capitani, Andrea; Capra, Alessandro; Castagnetti, Cristina; Corsini, Alessandro; Dubbini, Marco; Ronchetti, Francesco

The research object is the study and prevention of landslide risk through the utilization of integrated surveying systems like GPS and Automatic Total Station (Robotic station).The measurements have been applied to Boschi di Valoria landslide, located on Appennines of Modena in the Northern Italy, which relatively large size, about 1.6 square km, required the use of both techniques. The system is made by Automatic Total Station, looking at 45 reflectors and a GPS master station, reference for three rovers on the landslide. In order to monitor "local" disturbing effects, a bi-dimensional clinometer has been applied on the pilaster where the total station is located. In a first periodically measurements were collected, while the system is now performing continuously. The system permitted to evaluate movements from few millimeter till some meters per day in most dangerous areas; the entity of the movements obliged to plan an alert system that was activated after a first phase of phenomenon study. Topographic measurements have been integrated with geotechnical sensors (inclinometers and piezometers) in a GIS for landslide risk management.

2009 - Monitoring, modelling and mitigation of earth slides-earth flows in the northern Apennines [Articolo su rivista]
Borgatti, L.; Corsini, Alessandro; Ronchetti, Francesco

The article show some experiences about slow moving landslides monitoring and modelling, which are located in northern Appennines.

2009 - Stazione totale per il monitoraggio Leica TM30: test di verifica secondo norme DIN-18723 e test di funzionamento per il monitoraggio frane [Relazione in Atti di Convegno]
Bertacchini, E.; Boni, E.; Capitani, A.; Capra, A.; Castagnetti, C.; Corsini, A.; Dubbini, M.; Parmeggiani, E.

2009 - The role of geomorphology in land management. Modena - Alta Val Badia 13-18 September 2009. Field-trip guide [Monografia/Trattato scientifico]
V. M., Bruschi; Coratza, Paola; Corsini, Alessandro; Marchetti, Mauro; Panizza, Mario; Piacentini, Daniela; Soldati, Mauro

Si tratta della guida all'escursione in Alta Val Badia tenutasi in occasione del III Convegno Nazionale AIGeo (Modena e Alta Val Badia, 13-18 settembre 2010).

2009 - Weight of Evidence and Artificial Neural Networks for potential groundwater springs mapping: an application in Mt. Modino area (Northern Apennines, Italy) [Articolo su rivista]
Corsini, Alessandro; Cervi, Federico; Ronchetti, Francesco

Locations of potential groundwater springs were mapped in an area of 68 km2 in the Northern Apennines of Italy based on Weight of Evidence (WofE) and Radial Basis Function Link Net (RBFLN). A map of more than 200 springs and maps of five causal factors were uploaded to ArcGIS with Spatial Data Modelling extensions. The WofE and RBFLN potential groundwater spring maps had similar prediction rates, allowing about 50% of the training and validation springs to be predicted in about 15 to 20% of the study area. The two maps were merged using a heuristic combination matrix in order to produce two hybrid maps: one representing susceptible areas in both the WofE and RBFLN maps (type A), while the other representing susceptible areas at least in one of the two maps (type B). For small cumulated areas, the success rate of both hybrid maps was higher than that of the parent maps, while for large cumulated areas, only the type B hybrid map performed similarly to the parent maps. This conclusion suggests different applications of these maps to water management purposes.

2008 - Appraise the structural mitigation of landslide risk via numerical modelling: a case study from the northern Apennines (Italy) [Articolo su rivista]
L., Borgatti; Corsini, Alessandro; G., Marcato; Ronchetti, Francesco; L., Zabuski

The Ca’ Lita landslide is a large and deep-seated mass movement located in the northern Apennines, about 70 km west of Bologna (Northern Italy). It consists of a composite landslide that affects Cretaceous to Eocene flysch rock masses and chaotic complexes. Many of the sectors making up the landslide have resumed activity between 2002 and 2006, threatening some villages and an important road connecting several key industrial facilities located in the upper watershed. This paper presents the management of the emergency, dealing with the investigation campaigns (geological, geomorphological and LiDAR surveys, borehole drillings, seismic surveys), with the monitoring (in situ instrumentation) and with the design and construction of mitigation measures. The whole process, from landslide reactivation to date, has been modelled on a numerical basis with the finite difference code FLAC 2D, to assess the efficiency of the mitigation system and to propose further countermeasure works in different scenarios.

2008 - Collecting a multi-disciplinary field dataset to model the interactions between a flood control reservoir and the underlying porous aquifer (abstract) [Abstract in Atti di Convegno]
Borgatti, L.; Corsini, A.; Chiapponi, L.; D'Oria, M.; Giuffredi, F.; Lancellotta, R.; Mignosa, P.; Moretti, G.; Orlandini, S.; Pellegrini, M.; Remitti, F.; Ronchetti, F.; Tanda, M.; Zanini, A.

2008 - Inverse Parameter Identification Technique using PSO Algorithm applied to Geotechnical Modelling [Articolo su rivista]
Meier, J.; Schaedler, W.; Borgatti, L.; Corsini, Alessandro; Schanz, T.

This paper presents a concept for the application of particle swarm optimization in geotechnical engineering. For the calculationof deformations in soil or rock, numerical simulations based on continuum methods are widely used. The material behavior ismodeled using constitutive relations that require sets of material parameters to be specified. We present an inverse parameteridentification technique, based on statistical analyses and a particle swarm optimization algorithm, to be used in the calibrationprocess of geomechanical models. Its application is demonstrated with typical examples from the fields of soil mechanics andengineering geology. The results for two different laboratory tests and a natural slope clearly show that particle swarms are anefficient and fast tool for finding improved parameter sets to represent the measured reference data

2008 - Large Slow-moving Rock Slides – Earth Flows: the Case Study of Ca’ Lita Landslide (Northern Apennines, Italy) [Relazione in Atti di Convegno]
Borgatti, L.; Corsini, Alessandro; Ronchetti, Francesco; Truffelli, G.

The Ca’ Lita landslide is a large and deep-seated mass movement located in the northern Apennines of Italy. It consists of a complex-composite landslide that affects Cretaceous to Eocene flysch rock masses and chaotic complexes. The landslide head zone resumed activity in 2002 and in 2004 the landslide was totally reactivated. More than 50 m retrogression of the scarp, and about 400 m advancement of the toe threatened villages and an important road connecting several key industrial facilities located in the upper watershed. A national state of emergency was declared by the Authorities, following the evolution of 2004. A large plan of civil protection interventions was implemented, aimed at the management of risk and at the identification and realisation of structural mitigation. The Ca’ Lita landslide is a noticeable case history both from the geomorphic and the risk management perspectives. The relatively fast evolution undergone by the phenomenon from 2002 to date, and the remarkable advancement of the toe, point out that total and partial reactivations of dormant landslides can cause unexpected consequences in terms of involvement of new areas that, in practice, have no previous hazard rating assigned. Also, the landslide is a test bed for coupled monitoring and mitigation actions that, in a relatively short time, have allowed passing from response, to mitigation and preparedness phases. In this work, the management of the emergency is presented in the frame of monitoring, mitigation and modelling activities that are the result of the shared effort of public offices and research institutes.

2008 - Modellazione numerica dei meccanismi di riattivazione di grandi frane per scivolamento di terra: l’esempio della frana di Tolara, Appennino settentrionale [Articolo su rivista]
Ronchetti, Francesco; Borgatti, L.; Cervi, Federico; Piccinini, L.; Corsini, Alessandro

The time and space evolution of large earth slides in weak and complex rockmasses, that characterize thenorthern Apennines, is depending on geological setting and past climate. At the present the reactivation of theselandslides are due to mainly to hydrogeological and geotechnical features. This paper describes the hydrogeological andgeotechnical features of these landslides and the reactivations mechanism using coupled 2D hydrogeological numericalmodel and limit equilibrium analysis (Geoslope, 2004). The case study is the Tolara landslide (Modena Apennines) thatresumed activity in 2002. In this landslide some hydrogeological and geotechnical data have been collected from 2003 todate.

2008 - MONITOR – Hazard Monitoring for Risk Assessment and Risk Communication [Articolo su rivista]
Mayer, R.; Plank, C.; Bohner, A.; Kollarits, S.; Corsini, Alessandro; Ronchetti, Francesco; Siegel, H.; Noessing, L.; Mair, V.; Sulzenbacher, U.; Tosoni, D.; Cimarosto, S.; Zanco, A.; Todorov, S.; Krastev, L.; Wergles, N.; Gasperl, W.; Mayerl, M.; Toli, T.; Haradalia, H.; Koutsias, N.; Kreuzer, S.; Liehr, C.; Rachoy, C.; Papez, J.; Jindra, P.

Protection against natural disasters is an increasing challenge for society. In many areas the frequent occurrence of natural hazards like e.g. floods, landslides and forest fires has become a constant threat for inhabitants, the habitat itself and its resources. The overall magnitude of damaging events in the last decade clearly shows the need for comprehensive and innovative risk management. It is absolutely necessary to implement controlling mechanisms for the protection of population, land use areas, infrastructure and the natural space in endangered areas.Therefore monitoring tools and appropriate simulation procedures are indispensable. They have to provide necessary information for risk evaluation, successful risk management and communication.These are the main tasks the trans-national INTERREG IIIB Cadses Project is dealing with. The report gives an insight into the particular activities and will present some results of MONITOR.

2008 - MONITOR: Hazard Monitoring for Risk Assessment and Risk Communication [Monografia/Trattato scientifico]
Kollarits, S.; Wergles, N.; Maurer, L.; Mayer, R.; Plank, C.; Corsini, Alessandro; Rachoy, C.; Siegel, H.; Tosoni, D.; Sulzenbacher, U.; Mair, V.; Nössing, L; Jindra, P.; Papez, J.; Cimarosto, S.; Campana, R.; Zanco, A.; Galuppo, A.; Koutsias, N.; Toli, T.; Hardalia, H.; Makrakis, T.; Todorov, S.; Scheikl, M.; Kreuzer, S.; Liehr, C.; Mayerl, M.; Gasperl, W.; Bohner, A.

Monitoring tools and appropriate simulation procedures are indispensable when it comes to providing vital information for risk evaluation, successful risk management and communication. New methods useful for monitoring, like new remote sensing and high resolution laserscan techniques, have been developed in the past. The value of these techniques can be calculated in theory but practical experience is limited. The main goal of the MONITOR (INTERREG IIIB CADSES) project was the improvement of the methodology of risk evaluation and communication by applying these innovative methods. The project partners represent authorities dealing with hazard processes as well as infrastructure and land-use experts. Monitoring methods for the assessment of natural hazards, differentiated by risk quality and risk quantity as well as by differing legislative and organisational environments, were compared and evaluated. The MONITOR project developed transnational, harmonised, best-practise methods for the implementation of monitoring on the basis of criteria of cost, reliability, quality, re- usability as well as applicability.

2008 - Monitoring Methods: Systems Behind a Safer Environment [Relazione in Atti di Convegno]
Corsini, Alessandro

The paper deals with the role of monitoringmethods in the broad range of actions thatcan be undertaken in order to make the environmentsafer from a man-kind perspective.Effort has been put into identifying and classifyingthe factors controlling the selection ofmonitoring methods, the key characteristicsof monitoring systems and the core group ofconstraining factors that must be consideredwhile choosing a monitoring system for aspecifi c purpose with reference to landsliderisk. The backbone structure of a decisionsupport system that can allow end-user toidentify sets of viable monitoring options hasbeen developed. While doing so, the specifi coperational differences between mainstreamin-situ and remote sensing method have beenidentifi ed and discussed.

2007 - A lacustrine record of early Holocene watershed events and vegetation history, Corvara in Badia, Dolomites (Italy) [Articolo su rivista]
Borgatti, L.; Ravazzi, C.; Donegana, M.; Corsini, Alessandro; Marchetti, Mauro; Soldati, Mauro

The early-middle Holocene lacustrine succession of Corvara in Badia (Italian Dolomites, 1521 m a.s.l.) records landslides and other watershed events before the onset of human pressure. The sensitivity of this archive to relate climate change, watershed processes and vegetation dynamics in the catchment has been explored through a stratigraphic study, including the analysis of sedimentological features, magnetic properties, palaeobotanical records and radiocarbon dating. A palaeolake existed between 10.1 k and 7 k cal. yr BP and was surrounded by a dense conifer forest. Long-term forest dynamics driven by ecological processes and by climatic conditions favourable to upward forest expansion is recorded throughout the pollen record. Within the fine clastic sedimentation, distinct layers enriched in organic debris of terrestrial origin have been attributed to instant events produced by mass movements. Their age fits the chronology of large landslide events already known in the catchment, enabling correlation of the field evidence of landslides with the lacustrine record. Landslide frequency is controlled by geological and structural factors, but it is significantly modulated by the centennial-millennial climatic phases that characterise the Holocene in the Alps. The taphonomical properties of pollen and macroremains provided valuable insight on the mechanism of watershed processes. Copyright (C) 2006 John Wiley & Sons, Ltd.

2007 - Analisi della predisposizione al manifestarsi di sorgenti in area appenninica: un approccio statistico applicato all’area del Monte Modino (Provincia di Modena) [Articolo su rivista]
Cervi, Federico; Corsini, Alessandro; Ghinoi, A.; Ronchetti, Francesco; Pellegrini, Maurizio

Il lavoro,centrato sull’applicazione di codici di calcolo statisticiin ambiente Arc-GIS già utilizzati nel campo dellaricerca geomineraria, intergrati con l’analisi dei complessiidrogeologici, permette l’individuazione delle zonepotenzialmente idonee al reperimento ed eventuale captazionedella risorsa. Il tipo di informazione ottenuta,integrata ad una carta dei complessi idrogeologici, èutile per la pianificazione dello sfruttamento e per latutela della risorsa idrica.

2007 - Consolidamento di versanti instabili mediante opere di contenimento strutturale e tecniche di drenaggio profondo: gli esempi di Acquabona, Cervarezza, Magliatica e Ca’ Lita (Appennino reggiano) [Articolo su rivista]
Sartini, G.; Caputo, G.; De Simone, N.; Truffelli, G.; Borgatti, L.; Cervi, Federico; Corsini, Alessandro; Ronchetti, Francesco

The consolidation works carried out by the Technical Service of Enza, Panaro and Secchia basins of ReggioEmilia (STB-RE) on four large landslides, located in the Northern Apennines, Italy, are described. These interventions havebeen focused on the use of specialised drainage and containment measures such as modular shields of draining wells andinspectionable draining wells (Ø 1500 mm), large-diameter wells and large-diameter pile (Ø 60 mm) retaining walls with tierods. The interventions carried out have allowed slopes to be consolidated and critical hydro-meteorological events to bemanaged after the implementation of works.

2007 - Hydro-mechanical mechanisms of landslide reactivation in heterogeneous rock masses of the northern Apennines (Italy) [Relazione in Atti di Convegno]
Borgatti, L.; Cervi, Federico; Corsini, Alessandro; Ronchetti, Francesco; Pellegrini, Maurizio

The prediction of landslide reactivations in space and time is of relevantpractical interest in the northern Apennines. Dormant or active earth slides-earth flows affect,directly or indirectly, about 1800 villages and many km of road networks. Four test sites havebeen studied and monitored in order to analyse hydro-mechanical conditions in and aroundthe landslides, prior or during reactivation events. Data from monitoring systems such aselectric piezometers, spring and stream discharge flow-meters, inclinometers, Time DomainReflectometry (TDR) cables, Differential Global Positioning System (DGPS) networks andwire extensometers have highlighted some interplay between flow and mass transfers fromstable rock masses to the landslide body, and within the landslide itself. Monitoring in the2004-2006 period has covered dormancy, reactivation and suspension phases, allowing someconsiderations to be drawn on the hydro-mechanical mechanisms that drive the reactivationof large and deep seated landslides.

2007 - Large Holocene mass movements in the Dolomites (Val Gardena and Val Badia) [Articolo su rivista]
Corsini, Alessandro

The paper deals with the occurrence of large landslides in the dolomites and with their relationships to geomorphic and palaeo-climatic conditions.

2007 - Numerical analysis of the effectiveness of countermeasure works on earth slide stabilization: a case study in South Tyrol (Italy). [Relazione in Atti di Convegno]
Marcato, G.; Borgatti, L.; Corsini, Alessandro; Pasuto, A.; Silvano, S.; Zabuski, L.

An active complex earth slide causes risk for the resort of Corvara in Badia(South Tyrol, Italy). Displacement rates measured in the source area from 2001 to 2004 byGPS and inclinometers ranged between mm and dm per month, with sliding depth varyingfrom 20 to 40 m. In this crucial sector of the landslide a mitigation option is the constructionof rows of wells coupled with pile-founded retaining structures. The effect of suchcountermeasures was estimated by finite difference method, using FLAC 2D programme.Elasto-visco-plastic behaviour along the sliding zone was simulated with Burger’s viscositymodel. Plasticity and viscosity parameters were determined in back analysis by fittingcomputed and measured displacements in fully saturated conditions. Numerical simulationshowed that lowering ground water level for several meters is not sufficient to significantlyreduce movement rate and that retaining structures introduced into the model do not achieve acomplete mitigation of movements, since parts of the slope far-off the structure keep moving.

2007 - Primi interventi di consolidamento sulle frane dei Boschi di Valoria, di Tolara e Lezza Nuova (Val Dolo e Val Dragone, Appennino modenese) [Articolo su rivista]
Leuratti, E.; Lucente, C. C.; Medda, E.; Manzi, V.; Corsini, Alessandro; Tosatti, Giovanni; Ronchetti, Francesco; Guerra, M.

A seguito degli intensi eventi pluviometrici verificatisi a partire dall’autunno 2000, l’Appennino emiliano è stato interessato da una forte ripresa del dissesto idrogeologico, in particolare nelle valli dei torrenti Dolo e Dragone (Prov. di Modena). Il Servizio Tecnico di Bacino ha realizzato numerosi interventi volti alla mitigazione del dissesto ed al ripristino delle infrastrutture danneggiate. Vengono descritte tre località nelle quali si sono concentrati gli interventi di stabilizzazione.

2007 - Studio, mitigazione e monitoraggio della frana di crollo coinvolgente la strada comunale “Tagliole–Lago Santo” (Comune di Pievepelago, Appennino modenese) [Articolo su rivista]
Leuratti, E.; Lucente, C. C.; Medda, E.; Corsini, Alessandro; Borghi, A.; Borgatti, L.


2007 - Suscettibilità per frane superficiali (shallow traslational slides e soil slips). Quadro Conoscitivo - Sistema ambientale – Allegato 06 - La Geologia e la Geomorfologia e Tavola 4 – Carta di suscettibilità per frane superficiali [Cartografia]
Corsini, Alessandro; Cervi, Federico

Il lavoro sintetizza metodi e risultati della mappatura della suscettibilità da frane superficiali dell'area collinare della Provincia di Reggio Emilia, effettuata per mezzo di analisi multivariate.

2007 - The Valoria landslide reactivation in 2005-2006 (Northern Apennines, Italy) [Articolo su rivista]
Ronchetti, Francesco; Borgatti, L.; Cervi, Federico; Lucente, C. C.; Veneziano, M.; Corsini, Alessandro

The research has shown that complex hydrogeological processes play an important role in reactivating the Valoria landslide. The main of these processes was identified and, with the aid of new investigations and monitoring systems, will be analyzed in further details.

2007 - Use of multitemporal airborne LiDAR surveys to analyse post-failure behaviour of earthslides [Articolo su rivista]
Corsini, Alessandro; Borgatti, L.; Coren, F.; Vellico, M.

Two helicopter-borne LiDAR surveys were conducted in August 2004 and May 2005 on a 2 km2earth flow that was totally reactivated in late winter 2004. Shaded view maps and differentialanalysis of terrain models from the two surveys allowed residual movements, as well as ruptureand accumulation features over the slope, to be assessed and mapped for the period between 2004and 2005. In particular, it has been made evident that residual movements involved about 20% ofthe whole landslide area. Retrogression of the crown zones, with a depletion estimated in theorder of maximum 20 m, was coupled with a more than 10 m advancement of the deeptranslational slide affecting earth and rock materials in the source area, that resulted in anapparent uplift of more than 15 m. Down slope, the upper accumulation lobe sector was loweredby about 10 m due to depletion and also by the progressive decrease in water content.This analysis proved the usefulness of LiDAR surveys for analysing post-failure behaviour ofthis type of mass movements.

2006 - Definizione della pericolosità e di possibili interventi di mitigazione della frana di Corvara in Badia [RELAZIONE TECNICO-ILLUSTRATIVA] [Altro]
Panizza, M.; Silvano, S.; Corsini, Alessandro; Soldati, Mauro; Marchetti, Mauro; Borgatti, L.; Ghinoi, A.; Piacentini, D.; Pasuto, A.; Zannoni, A.; Marcato, G.; Mantovani, M.; Tagliavini, F.; Moretto, S.

Trattasi di relazione tecnico illustrativa delle ricerche svolte nei Progetti di studio “Definizione della Pericolosità della Frana di Corvara” e “Studio della Frana di Passo Gardena”, Provincia di Bolzano, Alto Adige

2006 - Frana di Passo Gardena [Altro]
Panizza, M.; Silvano, S.; Corsini, Alessandro; Soldati, Mauro; Marchetti, Mauro; Borgatti, L.; Ghinoi, A.; Piacentini, D.; Pasuto, A.; Zannoni, A.; Marcato, G.; Mantovani, M.; Tagliavini, F.; Moretto, S.

Trattasi di relazione tecnico illustrativa delle ricerche svolte nei Progetti di studio “Definizione della Pericolosità della Frana di Corvara” e “Studio della Frana di Passo Gardena”, Provincia di Bolzano, Alto Adige

2006 - Geomorphological evolution of slopes and climate changes in northern Italy during the Late Quaternary: spatial and temporal distribution of landslides and landscape sensitivity implications [Articolo su rivista]
Soldati, Mauro; Borgatti, L.; Cavallin, A.; De Amicis, M.; Frigerio, S.; Giardino, M.; Mortara, G.; Pellegrini, G. B.; Ravazzi, C.; Surian, N.; Tellini, C.; Zanchi, A. in c. o. l. l. with Alberto W.; Albanese, D.; Chelli, A.; Corsini, Alessandro; Marchetti, Mauro; Palomba, M.; Panizza, Mario

This paper deals with the use of landslide records in the analysis oflandscape sensitivity, with pamcdar reference to climate change as aforcing process. The dating of past landslide events is useful to reconstruct the evolution of the slope-systern at a broad ternporal scale and to recognize the different formative events it has experienced. If the environrnentai context can be defined by rneans of a rndtidisciplinary approach which cornprises geornorphological, sedimentologicai, paiaeobotanical, dendrochronological and archaeologicai anaiysis, then a deep understanding of the relationship between the possible triggering factors and the responses of the landscape can be achieved. The goal is to recognize the ternporal changes through environrnentai factors which condition landsliding events such as climate, seismic activity, vegetation and land use, trying to identify the relationship between landslide events and their initiating process, which is known to be complicated by the behaviour and the propenies of the hiilslope systern, in other words its sensitivity.The conceptual and rnethodological aspects of the topic are discussed,aiming prirnarily at the reconstruction of the temporal occurrenceof landslides and at the assessrnent of possible clustering of climate-induced landslides, as a consequence of the slope-systern sensitivity to climate changes. Case studies in the Alps and in the northem Apennines are described and the research perspectives are outlined.

2006 - Investigation and monitoring on support to the structural mitigation of large slow moving landslides: an example from Ca’ Lita (Northern Apennines, Reggio Emilia, Italy) [Articolo su rivista]
Corsini, Alessandro; Borgatti, L.; Caputo, G.; De Simone, N.; Sartini, G.; Truffelli, G.

The Ca' Lita landslide is a large and deep-seated mass movement located in the Secchia River Valley, in the sector of the Northern Apennines falling into Reggio Emilia Province. about 70 km west of Bologna (Northern Italy). It consists of a composite landslide system that affects Cretaceous to Eocene flysch rock masses and chaotic complexes. Many of the components making up the landslide system have resumed activity between 2002 and 2004, and are now threatening some hamlets and an important road serving the upper watershed area of River Secchia, where many villages and key industrial facilities are located. This paper presents the analysis and the quantification of displacement rates and depths of the mass movements, based on geological and geomorphological surveys, differential DEM analysis, interpretation of underground stratigraphic and monitoring data collected during the investigation campaign that has been undertaken in order to design cost-effective mitigation structures, and that has been conducted with the joint collaboration between public offices and research institutes.

2006 - Large reactivated landslides in weak rock masses: a case study from the Northern Apennines (Italy) [Articolo su rivista]
Borgatti, L.; Corsini, Alessandro; Barbieri, Massimo; Sartini, G.; Truffelli, G.; Caputo, G.; Puglisi, C.

This case study paper is about a large rotational rock and earth slide-earth flow located in the Secchia River Valley, in the Northern Apennines of Italy, that has displayed multiple reactivation phases between 2002 and 2004. The main geological constraints of the mass movement are related to the overlap of flysch rock masses over clayey complexes that allows rock slides to take place in the source area. The disarrangement and weathering of rock masses following slope movements causes large amount of fine-grained debris to be accumulated on the slope and mobilised by earth sliding and flowing. Analysis of rainfall data at the onset of reactivation events has proved that they occurred after periods with cumulated values higher than the averages of the last 30 years. The quantification of the morphological modifications induced by these reactivations has been made possible by comparing pre- and post-event digital elevation models. Depletion and accumulation has been in the range Of 30 m in different parts of the slope. In particular, an advancement of the landslide toe of more than 400 m, which caused a 30-m thick landslide tip to deposit, has been clearly seen. Monitoring data regarding subsurface movements and surface tension crack widening (tension cracks so large as to be properly described at trenches) has shown that sliding surfaces as deep as 43 m exist in the upper part of the landslide, while the accumulation lobe has moved by sliding and flowing over surfaces as deep as some 10 m. Velocities of cm/day have been recorded in the deep surfaces and in widening trenches of the source area, while the advancement of the accumulation lobe has been estimated as having velocities of up to 10 m/day. Groundwater in the landslide body has been observed at depths of 5-15 m in the upper areas, while it is estimated as being at the ground level in the toe. On this basis, it is concluded that the landslide still has a high potential for further development, both in the upper landslide zone and in the toe area.

2006 - Space-borne and ground-based SAR interferometry as tools for landslide hazard management in civil protection [Articolo su rivista]
Corsini, Alessandro; Farina, P.; Antonello, G.; Barbieri, Massimo; Casagli, N.; Coren, F.; Guerri, L.; Ronchetti, Francesco; Sterzai, P.; Tarchi, D.

In recent years, SAR interferometry has become one of the most popular emerging techniques for the assessment of ground displacements, and, as such, it is of great interest as a possible operational tool for civil protection institutions having to deal with landslide risk. The paper presents some of the results obtained in northern Italy during a research project aimed at testing the potentiality of the application of C-band space-borne interferometry and Ku-band ground based interferometry during different specific civil protection activities. Main research objectives were the detection of the movements of complex earth and rock slides affecting built-up areas during the 1990s, and the near real-time monitoring of a reactivated rotational earth slide over an emergency period of 15 days. Results of space-borne interferometry did qualitatively fit with the geological interpretation of the mass movements and with ground truths such as damaged buildings and in situ monitoring systems. However, this was not achieved in quantitative terms, suggesting that this technique should be used limitedly for displacement recognition and not monitoring. On the other hand, ground-based interferometry proved valuable both for a qualitative and a quantitative estimate of slope movements. Nonetheless, the research has also enabled the limitations that are still to be tackled in order to bring these systems to an operational usage in civil protection to be highlighted.

2005 - Aspetti concettuali e operativi per la realizzazione di carte di pericolosità idrogeologica: l’esempio della metodologia CARG - Provincia Autonoma di Bolzano per il Foglio 028 “La Marmolada [Relazione in Atti di Convegno]
Corsini, Alessandro; Mair, V.; Panizza, Mario

La presente nota illustra gli aspetti concettuali e operativo insiti nella metodologia per la realizzazione della Carta della Pericolosità Geologica nel settore Alto Atesino del F° “La Marmolada” e, in conclusione, discuterne in modo critico anche nell’ottica di un utilizzo del prodotto per una susseguente determinazione del rischio specifico

2005 - Esempio di cartografia della pericolosità idrogeomorfologica (Capitolo 13.2) [Capitolo/Saggio]
Corsini, Alessandro

Capitolo tematico sulla cartografia della pericolosità idrogeomorfologica, con esempi dall'Alto Adige

2005 - Field monitoring of the Corvara landslide (Dolomites, Italy) and its relevance for hazard assessment [Articolo su rivista]
Corsini, Alessandro; Pasuto, M.; Soldati, Mauro; Zannoni, A.

The Corvara landslide is an active slow moving rotational earth slide - earth flow, located uphill of the village of Corvara inBadia, one of the main tourist centres in the Alta Badia valley in the Dolomites (Province of Bolzano, Italy). Present-daymovements of the Corvara landslide cause National Road 244 and other infrastructures to be damaged on a yearly basis. Themovements also give rise to more serious risk scenarios for some buildings located in front the toe of the landslide. For thesereasons, the landslide has been under observation since 1997 with various field devices that enable slope movements to bemonitored for hazard assessment purposes. Differential GPS measurements on a network of 47 benchmarks has shown thathorizontal movements at the surface of the landslide have ranged from a few centimetres to more than 1 m between September2001 and September 2002. Over the same period, vertical movements ranged from a few centimetres to about 10 cm, with themaximum displacement rate being recorded in the track zone and in the uppermost part of the accumulation lobe of thelandslide. Borehole systems, such as inclinometers and TDR cables, have recorded similar rates of movement, with the depthsof the major active shear surfaces ranging from 48 m to about 10 m. From these data, it is estimated that the active component ofthe landslide has a volume of about 50 million m3. In this paper the monitoring data collected so far are presented and discussedin detail to prove that the hazard for the Corvara landslide, considered as the product of yearly probability of occurrence andmagnitude of the phenomenon, can be regarded has as medium or high if the velocity or alternatively the volume involved isconsidered. Finally, it is also concluded that the monitoring results obtained provide a sound basis on which to develop andvalidate numerical models, manage hazard and support the identification of viable passive and active mitigation measures.

2005 - Monitoraggio di grandi frane riattivate e sospese nella valle del Fiume Secchia (Appennino settentrionale) [Articolo su rivista]
Corsini, Alessandro; Borgatti, L.; Pellegrini, M.; Ronchetti, Francesco; con la collaborazione di Borghi, A.; Campagnoli, I.; Caputo, G.; Gatti, A.; Leuratti, E.; Lucente, C. C.; Truffelli, G.; Sartini, G.

Large complex landslides of prehistoric age, that are coupling multiple roto-traslational rock slides at the crownto earth slides and earth flows in the intermediate and lower part of the slope, are widespread over the Northern Apenninesof Italy. Typically, these landslides alternate decades or centuries long dormancy periods, to shorter periods characterised bythe alternation between reactivation events and phases of suspended activity. This note deals with four landslides of thiskind, that have been repetitively reactivated in the last decade causing damages to key road connections in thesubcatchments of Secchia River. A comparative analysis of data from the four sites collected with monitoring systems suchas inclinometers, TDR cables, wire extensometers, GPS benchmarks networks and automated electric piezometers, has beencarried out. This has enabled the kinematics and hydrogeologic characteristics of the landslide during the suspended activityphases, and during the most recent reactivation phases, to be reconstructed. This has yield indications that can have ageneral validity for these type of mass movements.

2005 - Survey and monitoring of landslide displacements by means of L-band satellite SAR interferometry [Articolo su rivista]
Strozzi, T.; Farina, P.; Corsini, Alessandro; Ambrosi, C.; Thüring, M.; Zilger, J.; Wiesmann, A.; Wegmüller, U.; Werner, C.

This paper illustrates the capabilities of L-band satellite SAR interferometry for the investigation of landslide displacements. SAR data acquired by the L-band JERS satellite over the Italian and Swiss Alps have been analyzed together with C-band ERS-1/2 SAR data and in situ information. The use of L-band SAR data with a wavelength larger than the usual C-band, generally considered for ground motion measurements, reduces some of the limitations of differential SAR interferometry, in particular, signal decorrelation induced by vegetation cover and rapid displacements. The sites of the Alta Val Badia region in South Tyrol (Italy), Ruinon in Lombardia (Italy), Saas Grund in Valais (Switzerland) and Campo Vallemaggia in Ticino (Switzerland), representing a comprehensive set of different mass wasting phenomena in various environments, are considered. The landslides in the Alta Val Badia region are good examples for presenting the improved performance of L-band in comparison to C-band for vegetated areas, in particular concerning open forest. The landslides of Ruinon, Saas Grund, and Campo Vallemaggia demonstrate the strength of L-band in observing moderately fist displacements in comparison to C-band. This work, performed with historical SAR data from a satellite which operated until 19 8, demonstrates the capabilities of future planned L-band SAR missions, like ALOS and TerraSAR-L, for landslide studies.

2004 - Application of an Integrated Method for Landslide Hazard Assessment in the Area of Corvara in Badia (Dolomites, Italy). [Capitolo/Saggio]
Corsini, Alessandro; Soldati, Mauro

The area of Corvara in Badia (Dolomites, Italy) has undergone detailed geomorphological investigation aiming at the identification, characterisation and management of mass movements within the framework of the NEWTECH Project (New technologies for landslide hazard assessment and management in Europe) funded by the European Union. From the Lateglacial, the area of Corvara in Badia has been thoroughly modelled by slope processes which resulted on a variety of landslides, some of which are still active today. In particular, some active mass movements affect tourist infrastructures and roads on the slope of Col Alto - Pralongià, located immediately to the SE of the village of Corvara in Badia. This paper presents the four main phases that make up the method adopted for integrated landslide hazard assessment in the area of Corvara in Badia. The first phase consisted in a geomorphological survey of the valley which led to the elaboration of a geomorphological map at a 1:10,000 scale. In particular, this phase enabled landslides location and type to be characterised. The second phase of the research was focused on the Col Alto - Pralongià slope and consisted of a detailed analysis of slope instability conditions. This enabled the type and state of activity of the geomorphological effects of slope instability to be defined and mapped at a 1:5000 scale. At the same time, this phase permitted the main determining causes of slope instability, such as geotechnical and geomechanical properties, slope morphometry etc., to be analysed and mapped at the same scale. The third phase of the research included databases implementation and GIS-based data analysis which eventually led to the elaboration and publication of a landslide susceptibility map at a 1:5000 scale. The fourth and the last phase of the research, which led to an integrated assessment of landslide hazard in the Col Alto - Pralongià slope, consisted in the integration of susceptibility information with hydrological, geotechnical, monitoring and recurrence data, thus producing a qualitative assessment of the triggering mechanisms and of their possible return times.

2004 - Cartographie du risque des mouvements de terrain in Italie: un exemple d'une étude pilote au Tyrol du Sud [Capitolo/Saggio]
Panizza, Mario; Corsini, Alessandro; Marchetti, Mauro; A., Pasuto; S., Silvano; Soldati, Mauro

Vengono illustrati i risultati relativi alla cartografia del rischio da frana condotti nell'Alto Adige con particolare riferimento all'Alta Val Badia.

2004 - Demonstration of the capabilities of L-band SAR interferometry for landslide deformation monitoring using JERS-1 data [Relazione in Atti di Convegno]
Strozzi, T.; Farina, P.; Corsini, Alessandro; Zilger, J.; Wiesmann, A.; Wegmüller, U.; Werner, C.


2004 - Geomorphology and slope instability in the Dolomites (Northern Italy): from Lateglacial to recent geomorphological evidence and engineering geological applications. [Articolo su rivista]
L., Borgatti; Soldati, Mauro; A., Carton; Corsini, Alessandro; A., Galuppo; Ghinoi, Alessandro; Marchetti, Mauro; E., Oddone; Panizza, Mario; A., Pasuto; G. B., Pellegrini; E., Schiavon; C., Siorpaes; N., Surian; F., Tagliavini

The aim of the paper is to show significant cases of mass movements of various types, sizes and ages which have affected the dolomitic valleys since the retreat of the Last Glacial Maximum (LGM) glaciers, including the recent catastrophic Vajont landslide which occurred in 1963. Mass movements often interfere with transport infrastructures and developed areas where a large number of tourists are present during both winter and summer. In these conditions of high vulnerability, even mass movements of modest magnitude, like debris flows, could have severe and sometimes unacceptable consequences.The secondary aims of the are, on the one hand, to highlight the relationships between geological structures and landscape evolution and, on the other hand, to show the influence of Holocene climatic changes on slope instability processes.

2004 - Hystorical and recent hydrogeological instability in the Monte Modino area: Valoria, Tolara and Lezza Nuova landslide reactivations (Dolo – Dragone valleys, Modena Apennines, Italy) [Articolo su rivista]
Manzi, V.; Leuratti, E.; Lucente, C. C.; Medda, E.; Guerra, M.; Corsini, Alessandro

Following the heavy rainfalls of autumn 2000 a strong resumption of hydrogeologicalinstability was observed throughout the whole Emilian Apennines. In the Modena provincethe effect of such event was the reactivation of many landslides. In the Monte Modino area(an elongated mountain ridge bounded by Dolo and Dragone stream valleys, high ModenaApennines) three large complex landslides (Valoria, Tolara and Lezza Nuova) werereactivated. While landslides were triggered by a strong increase in precipitation, the maincause of slope instability is possibly related to the peculiar hydrogeological setting of thewatershed: a thick unit of highly fracturated sandstones overlying a clayey formation. Inthis paper, the role of abundant rainfall events, periodically occurring in the ModenaApennines, as primary cause for landslide reactivation is discussed.The preliminary stabilisation works adopted by the “Servizio Tecnico Bacini Panaro edestra Secchia Modena”, have been restricted to restoration of slope stability withrehabilitation of the drainage system within each single landslide, mainly duringemergencies.We believe that, due to the peculiar hydrogeological setting of Monte Modino area, futureinterventions should provide the stabilization of the whole watershed area. An overalldrainage of Monte Modino sandstone unit is proposed to achieve this target.

2004 - Il telerilevamento nello studio delle frane: esempi nel territorio del Frignano [Capitolo/Saggio]
Corsini, Alessandro

La presente nota illustra brevemente tre esperienze di studio condotte nel campo del telerilevamento di frane nel territorio del Frignano, nell’ambito di una convenzione stipulata tra la Regione Emilia-Romagna (Servizio Protezione Civile, Responsabile Ing. Demetrio EGIDI) e le Università di Modena e Reggio Emilia e Università di Firenze, in quanto afferenti ai progetti di ricerca del Gruppo Nazionale Difesa Catastrofi Idrogeologiche del C.NR. Tale ricerca è finalizzata all’analisi geologico-tecnica di alcuni grandi dissesti che causano rischio per centri abitati e, tra i vari aspetti, prevede anche l’applicazione di tecniche di monitoraggio di tipo innovativo basate sul telerilevamento radar.

2004 - Landslides and climate change in the Italian Dolomites since the Lateglacial [Articolo su rivista]
Soldati, Mauro; Corsini, Alessandro; A., Pasuto

The paper deals with the relationship between the temporal occurrence of landslides and climatic changes in the period ranging from the Late-glacial to the present in the Italian Dolomites. After an introduction on the state-of-the-art, with particular reference to the Alpine region, and showing the promising aspects and main constraints of the research in this field, the results of recent investigations carried out in the two study sites are illustrated.The first study site is that of the Cortina d'Ampezzo, where several landslides have been identified and dated mainly by means of radiometric methods. The most ancient dates thus determined refer both to large rock slides which affected the dolomitic slopes after the withdrawal of LGM glaciers and to slides and flows mainly occurring on pelitic materials of the valley floors (from 13,000 to 10,000 cal. yr BP).Other datings allowed a series of flows which developed between 5500 and 2500 yr BP to be detected. For the latter, though, it was not possible to define whether they were reactivations of ancient mass movements or first-time landslides. In the Alta Val Badia the most ancient events go back to 10,000 and 9000 yr BP. In particular, they correspond to earth flows following vast rotational slides affecting the bedrock up to a depth of about 50 m. More recent earth flows, involving more modest amounts of material, took place some 5000 to 2000 yr BP.By analysing the dates so far obtained in the two study areas, it was possible to correlate the recorded increase of landslide activity with the climatic changes occurring at the boundary between the Lateglacial and the Holocene and between the Atlantic and the Sub-Boreal. The types and causes of landslides taking place in these two periods are, in any case, substantially different with respect to the different morphoclimatic conditions which existed in the two areas when these mass movements were triggered. Nevertheless, the Cortina d'Ampezzo area and the Alta Val Badia were affected by landslides also in other periods of the Holocene. This fact witnesses the importance of non-climatic causes, such as geological-structural factors. Notwithstanding this, by considering the results obtained it may be stated that many dated landslides can be considered as indicators of climatic changes.

2004 - Space-borne and ground-based SAR interferometry for landslide activity analysis and monitoring in the Appennines of Emilia Romagna (Italy): review of methods and preliminary results [Relazione in Atti di Convegno]
Barbieri, Massimo; Corsini, Alessandro; Casagli, N.; Farina, P.; Coren, F.; Sterzai, P.; Leva, D.; Tarchi, D.

This work concerns the application of SAR interferometry for the assessment of the long-term analysis of the state ofactivity of deep seated mass movements affecting some urban areas in the northern Appennines of Emilia Romagnaregion (from 1994-2001 space-borne ERS data) and for the real-time monitoring of active flow-like landslides in year2002 (from ground-based system). These activities are part of an ongoing research project supported by civil protectionauthorities of the Emilia-Romagna region that involves several research institutes with diverse expertises. A set of testsites characterized by a high landslide risk have been selected mainly taking into account phenomena characteristicssuch as deformation rates and vegetation coverage, with respect to the employed techniques. After a preliminarydetailed geomorphologic characterization of the sites, the interferometric analyses, still in progress, have beenimplemented. In particular space-borne DInSAR has been applied for 10 unstable areas using a set of ERS1/ERS2 dataacquired in the last 7 years. From 9 interferograms, the line-of-sight displacement maps have been calculated and, lateron, post processed in GIS environment in order to have on-slope-direction displacement maps that could fully beintegrated with geomorphologic and ancillary data and that could semi-quantitatively be compared with other traditionalmonitoring data. The results obtained have been rather satisfactory, especially in some test sites where entire villagesare settled on the mass movement, as in the case of Berceto (Parma) presented in the paper, and post-processed productshave proved a significant amelioration of basic interferometric ones. Moreover, in order to measure terraindisplacements induced by landslide characterized by high deformation rates and little urbanisation, ground-based SARinterferometry (GBInSAR) has been used for the monitoring of a test site located in the province of Bologna. Thisapplication proved that the LISA system adopted performs well even in clayey wet material, where signal attenuation isgenerally very strong.

2004 - Support of Satellite Radar to Hazard Zone Mapping in the Italian Alps [Relazione in Atti di Convegno]
Belitz, K.; Corsini, Alessandro; Mair, V.; Strozzi, T.; Wegmüller, U.; Zilger, J.

Living in areas of highly active natural processes as the alpine environment demands the careful assessment of naturalhazards and their provision in regional and local development planning processes, providing the chance to substantiallyreduce damage and loss of property and lives. Consequently techniques for the corresponding tasks of mapping andmonitoring natural hazards are subject of ongoing challenging research in this region. Earth observation data andmethodology have proven to be able to provide mapping of the spatial distribution of different environmentalparameters but are still rarely included in operational administrative and planning processes of hazard management.The presented study focussed on the potential integration of Differential SAR Interferometry techniques into currenttasks of landslide hazard management in the Italian Alps including test-cases in the Province of Bolzano-South Tyrol. Aclose cooperation with the responsible Geologic Service was established for detailed regarding of the specific userrequirements.Limitations and obstacles of the potential support from earth observation techniques were considered carefully and thepath of integration of products and services into the users processing chain was analysed in detail under operationalaspects and demonstrated.

2003 - Banche dati e GIS per la valutazione della suscettibilità da frana a Corvara in Badia [Relazione in Atti di Convegno]
Bonomi, T.; Cavallin, A.; Corsini, A.; Geneletti, D.; Napolitano, P.; Verro, R.

2003 - Conseguenze geomorfologiche di una faglia neotettonica nell’Alta Val Badia (Dolomiti) [Relazione in Atti di Convegno]
Corsini, Alessandro; Panizza, Mario

Si tratta di una faglia che si sviluppa nell’Alta Val Badia, con direzione NNW-SSE, lungo l’allineamento Col da Oi - rifugio Gardenaccia - Col Alto - Passo Incisa - Rio Salvazza, identificata per la prima volta da Panizza & alii (1978). Essa ha avuto importanti conseguenze geomorfologiche sia dirette, quale la formazione di numerosi piani e scarpate di faglia, sia indirette, quali i numerosi, vari, profondi ed estesi fenomeni di frana che si rinvengono lungo tutto il suo percorso. Viene qui illustrato il quadro, aggiornato sulla base dei rilievi condotti negli ultimi anni e avvalorato da datazioni al radiocarbonio di corpi di frana legati alla presenza della linea tettonica, delle evidenze geomorfologiche e geologiche di campagna che permettono di confermare e precisare le ipotesi di Panizza & alii (1978) già riprese successivamente da Castaldini & Panizza (1991). In particolare, tutti i dati, le evidenze e gli indizi morfoneotettonici e geologici rinvenuti permettono di classificare il lineamento come “elemento neotettonico ritenuto attivo in base ai numerosi, qualificati e congruenti indizi geomorfologici” secondo la nomenclatura di Panizza & alii (1987). Essi inoltre fanno ritenere la faglia attiva nel Pleistocene e forse nell’Olocene, con movimento prevalentemente orizzontale destrorso. La faglia, infine, può essere ritenuta “capace”, sia secondo la definizione di IAEA che quella di USMRC (cfr. Caggiano, 1979).

2003 - Le frane come indicatori di variazioni climatiche dal Tardiglaciale ad oggi nelle Dolomiti [Relazione in Atti di Convegno]
Pasuto, A.; Corsini, Alessandro; Soldati, Mauro

La presente nota riferisce dei risultati di recenti ricerche condotte nell'area di Cortina d'Ampezzo e in Val Badia (Dolomiti) relativamente ai rapporti fra ricerrenza di fenomeni franosi e variazioni climatiche dal Tardiglaciale ad oggi.

2003 - Mobilizzazione di Piombo e Zinco dal sito minerario di Viarago (Pergine Valsugana, Trento): valutazione di impatto sulla qualità ambientale [Relazione in Atti di Convegno]
Corsini, Alessandro; Matteucci, C.; Mazzucchelli, Maurizio; Piacentini, D.

Oggetto del presente studio è la valutazione dell’impatto sulla qualità ambientale connesso con lo sfruttamento, in epoca storica e fino al 1940, di manifestazioni filoniane a solfuri misti nei pressi di Viarago, nel comune di Pergine Valsugana (Trento). In particolare, lo studio analizza gli effetti connessi con la deposizione nei suoli sottostanti il sito minerario di metalli pesanti, soprattutto Pb e Zn, che vengono rilasciati dall’accumulo di materiale di scarto che ricopre il versante oggetto dell’attività estrattiva. L’approccio adottato per la valutazione della qualità ambientale dell’area di studio è stato mutuato dal progetto europeo ELANEM (Euro-Latin American Network on Enviromental Assessment and Monitoring) in cui il presente lavoro si inquadra. Questo approccio prevede l’analisi di indicatori di pressione, stato e risposta relativi a varie componenti ambientali (biota, risorse fisiche, clima, aria, pericolosità geologica, etc.) e la loro combinazione, relativamente alle funzioni ambientali di cui sono rappresentativi (Naturalità, Risorse, Smaltimento Rifiuti, Supporto e Servizi), al fine di ottenere valori indice per le diverse funzioni ambientali stesse. Gli indici sono poi, a loro volta utilizzati per ricavare un valore indice integrato di qualità ambientale. Lo studio si è avvalso di dati ricavati da rilievi diretti sul terreno (relativamente a geomorfologia, pedologia, vegetazione), campionamenti di suoli, analisi di laboratorio e ricerche presso enti pubblici e privati. Tutta la procedura di elaborazione dati è stata effettuata in ambiente GIS. E stato in primo luogo evidenziato che i microelementi considerati, ovvero Pb e Zn, assumono concentrazioni elevate nella zona dell’accumulo detritico e in quelle ad esso direttamente sottostanti, raggiungendo valori di gran lunga superiori al limite di attenzione indicati dalla Legge 478/82. I vari elaborati cartografici prodotti e rappresentativi di indici di funzioni e qualità ambientale hanno permesso di evidenziare che l’area di studio presenta valori assoluti di qualità ambientale che si attestano su classi assolute medie, differenziate però in maniera più evidente in termini relativi specifici per l’area. L’impatto della miniera sulla qualità ambientale dell’area è stato valutato effettuando un confronto tra le carte di indici di funzioni e di qualità ambientale ottenute nelle condizioni reali e carte analoghe ottenute simulando l’assenza di tutte le pressioni e variazioni di stato connesse con la miniera stessa. Rispetto la funzione ambientale “naturalità”, si è notato che in presenza della miniera un’ampia zona ad essa sottostante presenta valori relativi dell’indice di Naturalità da bassi a medi con piccole unità con valori molto bassi. Nell’analoga carta relativa alla condizione ipotetica tale zona è assente. Situazione pressoché analoga si è riscontrata per le altre funzioni ambientali e quindi, di conseguenza per i valori dell’indice integrato di qualità ambientale, che risultano bassi e medi nella zona limitrofa alla miniera, ma che sarebbero medi o alti senza la miniera. Da tali risultati ottenuti è evidente che un eventuale intervento di bonifica dell’area dovrebbe essere mirato a limitare l’alterazione del detrito di scarto e quindi la mobilizzazione di metalli pesanti, per esempio tramite la messa in posto di una copertura di materiali terrigeni, su cui far sviluppare un suolo e, in fase successiva, attecchire la vegetazione.

2003 - Resistivity profiles of a deep-seated rotational earthslide - earthflow in Corvara in Badia (Dolomites, Italy): data processing and geological interpretation [Relazione in Atti di Convegno]
Corsini, Alessandro; Arndt, R.

Sono qui presentati i risultati di due campagne di indagini geoelettriche condotte nel 2000 e 2001 sulla frana di Corvara, con particolare riferimento alla procedura di elaborazione dati adottata e all’interpretazione geologica dei profili di resistività ottenuti. Questo tipo di indagine geofisica, generalmente poco efficace in situazioni di frana, è stata scelta e sperimentata dopo che una iniziale campagna di rilievi con sismica a rifrazione non aveva prodotto risultati utili e dopo di che l’opzione della sismica a riflessione era stata temporaneamente accantonata per problemi logistici legati anche al trasporto di sorgenti potenti sui terreni impervi da studiare. Detto ciò, un tentativo è stato fatto di superare i limiti insiti in questo metodo sviluppando e adottando una procedura di elaborazione dati inedita in grado di escludere artefatti di resistività e definire i margini di errore del rilievo. La frana oggetto di indagine è uno scivolamento rotazionale - colata di terra attivo, ampio circa 2.5 km2 e profondo fino a oltre 90 m, che, innescatosi all’inizio dell’Olocene, danneggia attualmente linee elettriche, infrastrutture turistiche e una strada statale (CORSINI ET ALII, 1999; CORSINI ET ALII, 2000; CORSINI ET ALII, 2001). Il fenomeno, oggetto di studio dal 1997, è monitorato con un certo numero di inclinometri, cavi TDR e piezometri che hanno permesso di evidenziare le principali superfici di scivolamento. Tali strumentazioni sono stati installati in fori di sondaggio, da cui sono state ricostruite la stratigrafia e le caratteristiche dei materiali di frana, e la profondità del substrato roccioso (CORSINI ET ALII, 2002). Come prevedibile anche prima dell’esecuzione dei rilievi, la frana di Corvara ha rappresentato altresì una difficile prova della capacità dei metodi geoelettrici di essere di supporto alla ricostruzione della stratigrafia del substrato in condizioni topografiche e litologiche difficili. Relativamente a queste ultime, caratterizzate dalla presenza di un litosoma di frana argilloso e di un substrato litologicamente complesso (tipo B1, AGI 1985) e ricco anch’esso di livelli argillosi, la principale difficoltà deriva dalla variabilità dei valori di resistività assunti da materiali simili (in relazione al contenuto d’acqua e al grado di alterazione) che di conseguenza causa anche una convergenza di valori di resistività ottenuti da materiali diversi. Nel complesso sono stati rilevati 10 profili tra trasversali e longitudinali (il più lungo è circa 1100 m, i più corti circa 300 m, e nel complesso si sono coperti circa 6300 metri di profili) utilizzando la configurazione Wenner - Schlum¬berger, 100 nodi, spaziatura degli elettrodi variabile tra 5 e 15 m, e tempi di lettura da un paio d’ore a più di 20 ore. I profili sono stati distribuiti tra l’ area sorgente, quella di trasporto e l’accumulo della frana. La sequenza di elaborazione dati adottata, iniziata con l’inversione dei dati secondo l’algoritmo di Loke (LOKE, 2001), ha permesso di definire il margine di errore medio del rilievo, di raggruppare in classi significative i valori di resistività ottenuti, di creare pseudo sezioni rappresentanti il contributo qualitativo di ciascun blocco del modello e, infine, di realizzare profili di resistività semplificati, ripuliti di artefatti generati da variazioni di resistività inferiori a margine di errore medio del rilievo. Questi profili rielaborati sono stati confrontati e integrati coi dati di sondaggio, permettendo di ottenere un’interpretazione geologica della stratigrafia del substrato di ognuno di essi. Gli aspetti geologici di maggior interesse evidenziati da alcuni profili di qualità, sono il sistema a tre livelli della frana nella zona di trasporto e in quella d’accumulo (ovvero, un livello superiore costituito da colate di terra attive di età più giovane, un livello intermedio costituito da cola

2002 - A GIS-based model for Geomorphological Impact Assessment of a railway track [Articolo su rivista]
Barbieri, Massimo; Bonachea, J.; Corsini, Alessandro; Giusti, C.

The paper illustrates a method for the assessment of geomorphological impacts and risks related to the construction of an high speed railway track. The method has been applied in the study area of Castelfranco Emilia Municipality (Province of Modena, northern Italy) as part of the activities of the EC-project GETS. The method fits into general Multi-Criteria Analysis procedures and it is based on the use of GIS, to store, elaborate and manage maps making up the basic components of impact and risk matrices. Three possible tracks of the railway and geomorphological components falling into the assets, resources and processes categories, have been considered in the analysis. In the end, a number of impact and risk maps has been generated and combined in order to estimate impacts and risks for each alternative and provide decision makers with cartographic tools to evaluate the best possible alternative track from the geomorphological standpoint.

2002 - A GIS-based model for Geomorphological Impact Assessment of a railway track in Castelfranco Emilia territory (Italy) [Relazione in Atti di Convegno]
Giusti, C.; Barbieri, Massimo; Bonachea, J.; Corsini, Alessandro

ISBN 2951831706This article illustrates a model for the assessment of geomorphological impacts and risks related to the construction of an high speed railway track. This model fits into general multi-criteria analysis methods based upon the use of GIS techniques, and has been tested in the study area of Castelfranco Emilia (Province of Modena, northern Italy). The core of the analysis is based on a series of crossing operations between thematic maps that enable the network of mutual interrelationships between geomorphological component and the alternative for the project to be outlined in impact and rick matrixes of maps.

2002 - Landslide risk mapping in high mountainsy: an example of pilot study in the Dolomites (Italy) [Relazione in Atti di Convegno]
Panizza, M.; Corsini, Alessandro; Marchetti, Mauro; Pasuto, A.; Silvano, S.; Soldati, Mauro

In Italy, hydro-geological hazards and risks maps have been laid out since many years already by research institutions (Universities, National Research Council, ENEA, etc.) and national and regional technical services (Geological Survey, Basin Authorities, Regions etc.). The procedures adopted have not followed common standards, but variables in relation to the expertise of the researchers involved, the characteristics of studied areas, scale of work, etc. This contribution presents the experience of a pilot study carried out by researchers of the University of Modena and Reggio Emilia and the National Research Council of Padua for the M unicipality of Corvara in Badia (South Tyrol), which extends for about 40 kmq and it is well known for its vocation to summer and winter tourism. The study was requested form the Autonomous Province of Bolzano - South Tyrol, and in particular the Geological and the Mountain Basins offices, and is one among the four carried out in South-Tyrol in order to test and define in further details the methodology suggested by the laws mentioned.

2002 - Researches for landslide hazard assessment in the area of Corvara in Badia (Dolomites, South Tyrol, Italy): a summary overview [Relazione in Atti di Convegno]
Corsini, A.; Pasuto, A.; Soldati, M.; Zannoni, A

2002 - Technical guidelines for the definition of a conceptual and geotechnical model of the Corvara landslide [Relazione in Atti di Convegno]
Corsini, Alessandro; Pasuto, A.; Soldati, Mauro; Zannoni, A.

This paper shows the technical guidelines and progress in underground data integration for the Corvara landslide (Dolomites, Italy). Different techniques have enabled, since 1996, a large number superficial and underground data of different nature to be collected. This large data set is now progressively transferred to a Geographic Information System (GIS) that will enable data visualisation and management on a planimetric perspective, as well as along cross sections. This will permit all the available data to be fully exploited to define a conceptual and geotechnical model of the phenomenon

2001 - Holocene slope dynamics in the area of Corvara in Badia (Dolomites, Italy): chronology and paleoclimatic significance of some landslides [Articolo su rivista]
Corsini, Alessandro; Marchetti, Mauro; Soldati, Mauro

The area of Corvara in Badia, located in the Dolomites (NE Italy), is characterised by mountain groups over 3000 m high (Sella and Puez-Gardenaccia) which are connected to valleys located at about 1500 m in altitude by means of steep slopes. Besides the lithological, neotectonic and climatic characteristics of the area, the high relief energy has favoured intense gravitational slope modelling throughout the Holocene.The study, which aimed at the reconstruction of the geomorphological evolution of the slopes surrounding the village of Corvara in Badia, has implied the geomorphological, stratigraphic and chronological analysis of landslide processes, in particular of those affecting the Col Alto - Pralongià slope, situated uphill of the village. The research has also investigated lacustrine deposits found in the surroundings of Corvara in Badia and downstream of the village, which are due to events of valley damming linked to a landslide detached form the Puez-Gardenaccia group (Col Maladat landslide). In particular, the analysis has made use of stratigraphic data obtained from boreholes, and of chronological data derived from radiocarbon dating of wood and peat remnants collected from the cores and from excavations carried out close to the surface.The study has pinpointed that the triggering of the large complex landslides affecting the Col Alto - Pralongià slope (Col Alto landslide, Arlara landslide and Corvara landslide) occurred in the early Holocene, and that subsequent phases of intense slope movements took place on the same slope during the Subboreal-Subatlantic. The 14C data gathered from landslides affecting the Col Alto - Pralongià slope have also permitted the various areas progressively involved in the movements to be identified and the chronology of deposits making up actual landslide accumulations to be reconstructed. Finally, it was also proved that the plain of Corvara in Badia was affected by lacustrine deposition during the Preboreal - Atlantic and again, but to a lesser extent, during the Subboreal-Subatlantic. The evidence of a significant temporal correlation between the development of mass movements on the Col Alto - Pralongià slope and the evolution of the Col Maladat landslide was therefore proved.Even if the landslides investigated are clearly influenced by geological factors, a cause-effect relationship seems to exist between the phases of slope dynamics outlined by the research and the climatic and environmental changes which have characterised the Holocene. The age of trigger of the landslides investigated corresponds to the early Holocene, a period that many Authors consider to be characterised by a rapid increase of temperature (followed by permafrost melting) and of precipitation. In the study area, this climate change caused in-depth infiltration and percolation of water, also favoured by the geological nature of the bedrock. A subsequent phase of slope instability, witnessed by the dating of several landslide events, corresponds to the climatic deterioration of the Subboreal - early Subatlantic periods, which has probably caused a large amount of meteoric water to be available on slopes.

2001 - Procedura per la Valutazione d'Impatto Ambientale (VIA) del Tracciato ad Alta Velocità nel comune di Castelfranco Emilia e aree limitrofe ((Provincia di Modena, Italia) [Articolo su rivista]
Panizza, Mario; Barbieri, Massimo; Bertens, J.; Bonachea, J.; Castaldini, Doriano; Corsini, Alessandro; Giusti, C.; Gonzalez Diez, A.; Marchetti, Mauro

This paper is about a procedure that has been developed for the assessment of geomorphological impacts and risks related to the construction of an High Speed Railway track. The method fits into general Multi-Criteria Analysis procedures and it is based on the use of GIS to store, elaborate and manage maps making up the basic components of impact and risk matrices

2001 - Uso Integrato di Banche dati spaziali e relazionali per la gestione di dati relativi a fenomeni franosi [Relazione in Atti di Convegno]
Bonomi, T.; Cavallin, A.; Corsini, Alessandro; Geneletti, D.; Napolitano, P.; Verro, R.

La presente note descrive la banca dati informatica realizzata nell’ambito del progetto europeo Newtech (New Technologies for Landslide Hazard Assessment and Management in Europe, Contratto n° ENV4-CT96-0248) per l’organizzazione e la gestione dei dati necessari per la valutazione della suscettibilità da frana di un area di circa 5 km2 sul versante nordoccidentale del rilievo Col Alto - Pralongià, nei pressi di Corvara in Badia (Provincia Autonoma di Bolzano). Inoltre, la banca dati ha costituito l’archivio informativo utilizzato per la valutazione qualitativa della pericolosità della frana di Corvara, il principale dei fenomeni franosi che interessano il suddetto versante.

2000 - Landslides and climate change in the Alps since the Late-Glacial: Evidence of case studies in the Dolomites (Italy) [Relazione in Atti di Convegno]
Corsini, Alessandro; Pasuto, A.; Soldati, Mauro

Since 1991, investigation on the relationships between landslide occurrence and climatic change from the Late-glacial have been carried out in the areas of Cortina d’Ampezzo and Alta Badia (Italy) within the realm of EU-funded projects. Such research, which also dealt with geomorphological and landslide hazard mapping, brought to a better understanding of the geomorphological evolution of these areas and took large benefit from radiocarbon dating of several mass movements. In particular, the study of the past distribution of landslides was fundamental for the definition of landslide hazard and for planning monitoring systems to be installed on the most active slope movements as well as for making speculations on the relationships between landslide occurrence and climate changes

2000 - L'influenza dei fenomeni franosi sull'evoluzione geomorfologica post-glaciale dell'Alta Val Badia e della Valparola (Dolomiti). [Monografia/Trattato scientifico]
Corsini, Alessandro

Il primo obiettivo delle ricerche geomorfologiche condotte nell’Alta Val Badia ed in Valparola è consistito nella ricostruzione dell’evoluzione geomorfologica post-würmiana dell’area, con particolare riguardo al riconoscimento del ruolo esercitato su di essa, nel lungo e nel breve termine, dai fenomeni franosi. Le forme ed i depositi di frana rappresentano infatti l’espressione morfologica più evidente dei vari processi gravitativi di versante che sono stati i principali artefici del modellamento del rilievo dell’area nel corso dell’Olocene e tuttora. A tale scopo, si è provveduto al riconoscimento delle principali forme e dei depositi, legati sia a processi morfogenetici ormai esauriti sia a quelli tuttora attivi, ed alla loro rappresentazione di sintesi in una carta geomorfologica alla scala 1:25.000 elaborata facendo riferimento alle linee guida del progetto “CARG” relative ai fogli della Carta Geomorfologica d’Italia alla scala 1:50.000 (Gruppo di Lavoro per la Cartografia Geomorfologica, 1994). Tra le vicende ambientali su cui si è posta particolare attenzione in fase di analisi, in quanto significative anche per lo sviluppo dei fenomeni franosi più antichi (Panizza, 1973), vi sono quelle legate alla progressiva scomparsa dall’area, nel Tardiglaciale, dei ghiacciai pleniglaciali e vallivi e delle zone con permafrost. Inoltre, è risultato molto importante, per gli scopi della ricerca, lo studio di taluni settori vallivi nei quali, durante l’Olocene, si sono formati e poi sono scomparsi specchi lacustri legati a fenomeni di sbarramento per frana. Fondamentale, ai fini di questo primo obiettivo, è stata la ricostruzione cronologica, in termini di date assolute, della ricorrenza temporale dei fenomeni franosi durante l’Olocene, tramite l’applicazione del metodo del radiocarbonio e, in seguito, l’analisi dei rapporti esistenti tra la distribuzione spaziale e temporale dei fenomeni franosi passati ed attuali dell’area ed i suoi caratteri paleoclimatici, questi ultimi ricostruiti sulla base di dati noti in letteratura e delle vicende ambientali ricostruite nella fase precedente. In quest’ambito, è stato inoltre condotto uno studio pilota atto a verificare l’applicabilità della Luminescenza Stimolata Otticamente alla datazione di sedimenti fini di origine lacustre, legati a sbarramento per frana, in ambiente dolomitico. Il secondo obiettivo della ricerca, ha riguardato invece l’analisi di dettaglio (scala 1:5000) dello stato di dissesto attuale di settori vallivi interessati da fenomeni franosi che inducono condizioni di rischio idrogeologico in zone fortemente antropizzate e, per gli stessi settori vallivi, l’identificazione di possibili scenari di evoluzione futura in termini di propensione e probabilità di dissesto. Questo ha comportato la ricostruzione morfologica e cronologica dell’evoluzione geomorfologica olocenica e recente dei versanti indagati, l’analisi degli effetti geomorfologici attuali dei dissesti (anche tramite l’ausilio di sistemi di monitoraggio) e, infine, l’identificazione dei fattori causali di tipo geologico ed orografico e l’applicazione di procedure di analisi delle relazione tra questi ed i dissesti basate sull’uso di Sistemi Informativi Territorial

1999 - Geomorphological Investigation and Management of the Corvara Landslide (Dolomites, Italy) [Articolo su rivista]
Corsini, Alessandro; Pasuto, A.; Soldati, Mauro

This paper shows the results of geomorphological investigation carried out in the area of Corvara inBadia (Dolomites) aiming at the recognition, characterisation and management of mass movements. Thearea studied, where tourism activities and infrastructures are highly developed, has been affected by severallandslides during the Holocene and is at present still endangered by active movements which affect roads,houses and ski runs. In particular, the investigation focused on the Corvara landslide which is the largest andmost hazardous mass movement in the area considered. It is a complex landslide located south-east of theCorvara village which affects the prevalently pelitic rocks of the S. Cassiano Formation (Lower Carnian)and La Valle Formation (Upper Ladinian).Detailed geomorphological survey and analyses of aerial photographs from different periods enabledthe definition of the state of activity and frequency of the landslide. At present, the most active sector is thesource area where retrogressive slides and flows show either continuous or seasonal mobilisation. On theother hand, the accumulation area shows minor, but still significant, longitudinal displacements, besidesconsiderable lateral reactivations due to the erosion caused by the two streams which flank the landslide.These reactivations are responsible for heavy and repeated damage to the national road 244. It is likely thatthis lateral erosion prevents more intense longitudinal displacements, since a condition of equilibrium isdetermined between the material deriving from the source area and that carried away by the water courses.Four boreholes were drilled on the landslide at different key points; the bedrock was found at a depthof 40 to 45 metres. These boreholes have been instrumented with inclinometers, extensometers, coaxialcables and piezometers in order to obtain further information on the geometry, hydrology and kinematics ofthe landslide.On the basis of the evidence gathered through geomorphological analysis and the first inclinometricmeasurements, it is plausible to suppose that larger sectors of the source area will reactivate, inducingeventually a hazardous advance of the landslide toe towards the village.

1998 - Indagini preliminari per la definizione della pericolosità da frana nella conca di Corvara in Badia (Dolomiti). [Articolo su rivista]
CORSINI, Alessandro; PANIZZA, Mario; Pasuto, A.; Silvano, S.; Siorpaes, C.; SOLDATI, Mauro

La presente nota costituisce dunque un contributo preliminare ai fini della valutazione della pericolosità da frana nella conca di Corvara in Badia. In particolare, dopo una descrizione delle caratteristiche geologiche e geomorfologiche, viene illustrata la frana di Corvara, il dissesto più imponente dell’Alta Badia. Lo studio di tale fenomeno presenta importanti risvolti applicativi sia perché il piede dell'accumulo lambisce l'abitato di Corvara sia perché sono interessati dal movimento la strada statale che scende dal Passo di Campolongo e alcuni impianti di risalita. Il presente studio si inserisce nell'ambito del progetto NEWTECH (“New technologies for landslide hazard assessment and management in Europe”) finanziato dalla Commissione Europea, DG XII, nell’ambito del Programma ENVIRONMENT & CLIMATE.

1998 - Report on the Use of New Landslide Susceptibility Mapping Techniques [Capitolo/Saggio]
Panizza, Mario; Corsini, Alessandro; Soldati, Mauro; Tosatti, Giovanni

Researchers from Modena University collaborated with researchers from Spain, Portugal and The Netherlands to develop and apply a new common methodological approach to geomorphological investigations, mapping and landslide hazard assessment using GIS. The report outlines how the task was fulfilled by the research teams involved in this project.

1998 - Valutazione della pericolosità da frana nell’area di Corvara in Badia (Dolomiti) [Capitolo/Saggio]
Panizza, M.; Bollettinari, G.; Bonomi, T.; Cavallin, A.; Corsini, A.; De Amicis, M.; Gandolfi, M.; Marchetti, M

1997 - The Use of New Mapping Techniques and GIS to Assess Landslide Susceptibility [Capitolo/Saggio]
Panizza, Mario; Soldati, Mauro; Bollettinari, G.; Corsini, Alessandro; Tosatti, Giovanni

Researchers from Modena University worked along with researchers from other European countries to develop a new common methodological approach to geomorphological investigations, mapping and landslide hazard assessment using GIS.