Antonello, G.

Ballini, A.

Casagli, Nicola

Del Ventisette, Chiara

Fortuny Guasch, J.

La Rocca, L.

Leva, Davide

Mannucci, G.

Tarchi, D.

English

Florence Research

Geophysical Research Abstracts,Vol. 10, EGU2008-A-08818, 2008SRef-ID: 1607-7962/gra/EGU2008-A-08818EGU General Assembly 2008© Author(s) 2008Ground-based interferometry for monitoring an activerockslide in the Italian AlpsN. Casagli (1), C. Del Ventisette (1), G. Mannucci (2), L. La Rocca (2), A. Ballini(2), G. Antonello (3), J. Fortuny-Guasch (3), D. Tarchi (3) and D. Leva (4)(1) Earth Sciences Department, University of Florence, Italy (e-mail: nicola.casagli@unifi.it),(2) Regional Agency for Environmental Protection, ARPA – Lombardia, Milano, Italy (e-mail:g.mannucci@arpalombardia.it), (3) Joint Research Center of the European Commission, IPSC,Ispra, Italy (e-mail: dario.tarchi@jrc.it), (4) LisaLab Ltd. a JRC spin-off company, Legnano,Italy (e-mail: davide.leva@lisalab.com)The ground based interferometry technique (GBInSAR) was applied to identify thedeformation on the Ruinon landslide in order to carry out a real time monitoring sys-tem.The Ruinon landslide is one of the most hazardous slope movements in the ItalianAlps. It is located in Valfurva (High Valtellina), near the village of Bormio, in theRhaetian Alps. The landslide is currently active, and its continuous movements affectan estimated volume of rock of about 30 million m3. This landslide represent a seriousthreat to human lives and socioeconomic activities in the area.The landslide is characterized by two main scarps oriented northwest-southeast, par-allel to the main fracture system recorded on the slope. The “upper scarp” is located atan elevation of about 2100 m above sea level (a.s.l.), the “lower scarp” at about 1900m a.s.l..The ground based linear SAR system installed to monitor the Ruinon Landslide wassettled up by the Joint Research Centre (JRC) of the European Commission and byLisaLab , a JRC spin-off company. The radar system was installed on the slope infront of the landslide, at an average distance of 1400 m. The system operates at afrequency of 17.35 GHz and produces a radar image of the observed area every 14.3minutes. The pixel resolution in range is about 1.5m while the resolution in azimuth isbetween 2.6m and 5.2m in relation to the distance between the sensor and the observedarea.The application of the radar interferometry technique through ground-based instru-mentation to the Ruinon landslide between 22/06/2006 and 22/06/2007, allow us toobtain multitemporal maps showing the complete displacement field of the landslideand to create, using binge of interference of the observed scene, velocity vs. timeplots for a lot of selected pixel. This type of information is fundamental for the earlydetection of landslide accelerations.The deformations are prevalently concentrated on two sectors; the first one corre-sponds to the east part of the upper scarp where the total displacement is of 636mm/year along the line-of-sight towards the sensor. The second one corresponds tothe upper sector of the lower scarp.The monthly displacement maps point out that the deformation rate, both on the “up-per scarp” and in the “lower scarp” decrease progressively from December 2006. Thevelocity of displacement increases from May 2007 especially in the faster sector ofthe landslide, localized in the upper scarp, where the velocity reached about 9 mm perday.Furthermore a comparison between velocity changes and major rainfalls has beenmade. Indeed the rapid increasing in velocity recorded by GBInSAR is the result of aquick response to rainfall intensity.Moreover, to validate a GBInSAR technique to monitor the Ruinon landslide, a com-parison between the GBInSAR data and the in situ measurements has been carriedout. At present the entire slope is monitored by the Geological Monitoring Centre ofthe Regional Agency for Environmental Protection (ARPA) of the Lombardia Region,through an extensive network composed of a series of extensometer and distometersensors, part of which are equipped for real-time data acquisition and transmission.The trends of deformation recorded from GBInSAR monitoring in several point of theRuinon landslide are comparable with those recorded from in situ measurements.

Ground-based interferometry for monitoring an active rockslide in the Italian Alps

https://flore.unifi.it/bitstream/2158/384573/1/Casagli%20et%20al%20GRA%20vol%2010%20EGU%202008.pdf

Ground-based interferometry for monitoring an active rockslide in the Italian Alps

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