Articles | Volume 11, issue 3
Nat. Hazards Earth Syst. Sci., 11, 865–881, 2011
Nat. Hazards Earth Syst. Sci., 11, 865–881, 2011

Research article 16 Mar 2011

Research article | 16 Mar 2011

Advanced radar-interpretation of InSAR time series for mapping and characterization of geological processes

F. Cigna1, C. Del Ventisette1, V. Liguori2, and N. Casagli1 F. Cigna et al.
  • 1Department of Earth Sciences, University of Firenze, Via La Pira 4, 50121 Firenze, Italy
  • 2Department of Civil and Environmental Engineering, University of Palermo, Viale delle Scienze, 90128 Palermo, Italy

Abstract. We present a new post-processing methodology for the analysis of InSAR (Synthetic Aperture Radar Interferometry) multi-temporal measures, based on the temporal under-sampling of displacement time series, the identification of potential changes occurring during the monitoring period and, eventually, the classification of different deformation behaviours. The potentials of this approach for the analysis of geological processes were tested on the case study of Naro (Italy), specifically selected due to its geological setting and related ground instability of unknown causes that occurred in February 2005. The time series analysis of past (ERS1/2 descending data; 1992–2000) and current (RADARSAT-1 ascending data; 2003–2007) ground movements highlighted significant displacement rates (up to 6 mm yr−1) in 2003–2007, followed by a post-event stabilization. The deformational behaviours of instable areas involved in the 2005 event were also detected, clarifying typology and kinematics of ground instability. The urban sectors affected and unaffected by the event were finally mapped, consequently re-defining and enlarging the influenced area previously detected by field observations. Through the integration of InSAR data and conventional field surveys (i.e. geological, geomorphologic and geostructural campaigns), the causes of instability were finally attributed to tectonics.