Big data managing in a landslide early warning system: Experience from a ground-based interferometric radar application

A big challenge in terms or landslide risk mitigation is represented by increasing the resiliency of society exposed to the risk. Among the possible strategies with which to reach this goal, there is the implementation of early warning systems. This paper describes a procedure to improve early warning activities in areas affected by high landslide risk, such as those classified as critical infrastructures for their central role in society. This research is part of the project LEWIS (Landslides Early Warning Integrated System): An Integrated System for Landslide Monitoring, Early Warning and Risk Mitigation along Lifelines. LEWIS is composed of a susceptibility assessment methodology providing information for single points and areal monitoring systems, a data transmission network and a data collecting and processing center (DCPC), where readings from all monitoring systems and mathematical models converge and which sets the basis for warning and intervention activities. The aim of this paper is to show how logistic issues linked to advanced monitoring techniques, such as big data transfer and storing, can be dealt with compatibly with an early warning system. Therefore, we focus on the interaction between an areal monitoring tool (a ground-based interferometric radar) and the DCPC. By converting complex data into ASCII strings and through appropriate data cropping and average, and by implementing an algorithm for line-of-sight correction, we managed to reduce the data daily output without compromising the capability for performing

Tectonic and sedimentary evolution of the Upper Valdarno Basin: new insights from the lacustrine S. Barbara Basin

We describe stratigraphic, structural and kinematic data from the sediments of the Upper Pliocene Santa Barbara Basin and from its substratum. The results shed light on the relationships between tectonics and sedimentation in the larger Late Pliocene-Middle Pleistocene Upper Valdarno Basin of which the Santa Barbara Basin is considered a precursor. The sediments filling up the Santa Barbara Basin are made up of alluvial to deltaic and lacustrine deposits, grouped in the Castelnuovo dei Sabbioni (CSB) Synthem, related to Late Pliocene. This synthem was deposited in a tectonic depression reasonably delimited to the East by a west-dipping normal fault system and delimited to the North and to the South by left-lateral trans-tensional shear zones, which controlled the main directions of the alluvial drainage. During Early Pleistocene, a new master normal fault system (Trappola fault system) developed further to the East, determining the widening of the previous tectonic depression, now delimited to the North and to the South by the regional Piombino-Faenza and Arbia-Val Marecchia transfer zones, respectively. In this new tectonic depression, with a dominant axial drainage direction, alluvial, fluvio-aeolian and fluvial sediments (Montevarchi Synthem, VRC) deposited during Early Pleistocene. The VRC Synthem, being located in the hanging-wall of the Trappola normal fault system, is slightly tilted to the NE. Finally, during Early-Middle Pleistocene, axial fluvial deposits (Torrente Ciuffenna Synthem, UFF), sealed the previously formed brittle structures. Our kinematic and structural data allow us to confirm the interpretation that the Santa Barbara Basin is the precursor of the Upper Valdarno Basin and that both basins developed in structural depressions formed by the interplay between normal and transfer faults, framed in the extensional tectonics which characterizes Tuscany since Miocene

Tectonic and sedimentary evolution of the Upper Valdarno Basin: new insights from the lacustrine S. Barbara Basin

We describe stratigraphic, structural and kinematic data from the sediments of the Upper Pliocene Santa Barbara Basin and from its substratum. The results shed light on the relationships between tectonics and sedimentation in the larger Late Pliocene-Middle Pleistocene Upper Valdarno Basin of which the Santa Barbara Basin is considered a precursor. The sediments filling up the Santa Bar- bara Basin are made up of alluvial to deltaic and lacustrine deposits, grouped in the Castelnuovo dei Sabbioni (CSB) Synthem, related to Late Pliocene. This synthem was deposited in a tectonic depression reasonably delimited to the East by a west-dipping normal fault sys- tem and delimited to the North and to the South by left-lateral trans- tensional shear zones, which controlled the main directions of the alluvial drainage. During Early Pleistocene, a new master normal fault system (Trappola fault system) developed further to the East, determining the widening of the previous tectonic depression, now delimited to the North and to the South by the regional Piombino- Faenza and Arbia-Val Marecchia transfer zones, respectively. In this new tectonic depression, with a dominant axial drainage direction, alluvial, fluvio-aeolian and fluvial sediments (Montevarchi Synthem, VRC) deposited during Early Pleistocene. The VRC Synthem, being located in the hanging-wall of the Trappola normal fault system, is slightly tilted to the NE. Finally, during Early-Middle Pleistocene, axial fluvial deposits (Torrente Ciuffenna Synthem, UFF), sealed the previously formed brittle structures. Our kinematic and structural data allow us to confirm the interpretation that the Santa Barbara Basin is the precursor of the Upper Valdarno Basin and that both basins developed in structural depressions formed by the interplay between normal and transfer faults, framed in the extensional tectonics which characterizes Tuscany since Miocene

Geomorphology of the Rotolon landslide (Veneto Region, Italy)

In this paper a geomorphological map of the Rotolon landslide is presented. This cartographic product was obtained using a combination of accurate field surveys together with airborne Lidar analysis, aerial photo interpretation and thermographic field surveys within a GIS. The map was prepared in order to analyze the morphological features of the landslide and therefore improve interpretation of the GB-InSAR data. This monitoring device was installed on the site after the detachment of a debris mass of 225,000 m3 on 4 November 2010. The main purpose of the post-event activities, including the geomorphological characterization, was to detect the processes acting on the landslide, evaluate the hazard related to each phenomenon, understand the landslide kinematics and define the residual risk for the area.The geomorphological map suggests that debris production and detachment are hazardous phenomena that involve the surficial detrital cover of a bigger and more complex landslide. The latter has the typical characteristics of a deep-seated gravitational slope deformation. The distinction between secondary processes, which appear to be the most hazardous in the short-term, and deep seated ones, demonstrates that accurate mapping provides important information for local administrations and decision makers, allowing them to prepare landslide susceptibility and hazard models

Geomorphological characterization, monitoring and modeling of the Monte Rotolon complex landslide (Recoaro Terme, Italy)

The Rotolon landslide, located in the upper Agno River valley (Vicenza, Italy), has threatened the valley for centuries. During November 2010, after 637 mm of rainfall in 12 days, a debris mass of about 225,000 m3 collapsed from the lowermost portion of the landslide and evolved into a debris flow that channeled in the Rotolon Creek riverbed, damaging the villages of Maltaure and Parlati in the Recoaro Terme municipality. On December 8th, 2010 the Department of Earth Sciences of the University of Firenze started a real-time monitoring using a GB-InSAR radar interferometer. The radar data are elaborated to obtain weekly, monthly and total cumulated 3D displacement maps and displacement time series of ten control points selected on the landslide mass. Accurate field surveys were carried out to analyze the landslide physiographic features and to validate the ground deformation retrieved from the radar data. The geomorphological features, supported by the radar data, led to an interpretation of the complex Rotolon landslide as a Deep Seated Gravitational Slope Deformation, whose detrital cover is often affected by detachments triggering debris flows. The November 2010 detachment area was modeled in order to: (i) calculate the main geotechnical properties of the collapsed material by means of a back analysis; (ii) define the residual risk; (iii) simulate new critical scenarios for the new topographic slope surface