GNGTS 2023 - Atti del 41° Convegno Nazionale

Session 1.2 GNGTS 2023 1992-2021 Campi Flegrei deformation history from satellite SAR missions M. Polcari, S. Borgstrom, C. Del Gaudio, P. De Martino, C. Ricco, V. Siniscalchi, E. Trasatti Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy Introduction Campi Flegrei caldera is a complex volcanic system located in southern Italy, well known for the related hazard due to the continuous volcanic and geothermal activity and the high population density. It is indeed characterized by bradyseism, a phenomenon causing ground level variations with ground uplift/subsidence rate of some cm/yr. These ground movements are clearly connected to the volcanic and geothermal activity of the caldera then the monitoring of the inflation and deflation phases allows to indirectly infer useful information about the volcanic source (De Natale et al, 1991; Trasatti et al., 2011; Amoruso et al, 2014). During the years, networks of continuous Global Navigation Satellite System (GNSS) stations and Levelling benchmarks have been installed in the area for monitoring the bradyseism of Campi Flegrei. However, since 1992, it can also be observed by satellite data acquired by Synthetic Aperture Radar (SAR) sensors which offer a denser spatial coverage with relatively low costs. SAR data processed by interferometric techniques (InSAR) have already been exploited for studying several phases of the Campi Flegrei bradysesism (Samsonov et al., Trasatti et al., 2015). However, according to the scientific aim of a study, only limited time windows have been analyzed. In addition, different working groups use different techniques, parameters and reference systems to elaborate the SAR images. This produces a data fragmentation with as consequence a lack of homogeneity and time continuity in Campi Flegrei ground deformation monitoring. Therefore, the aim of the present work is to provide the scientific community with a continuous InSAR dataset, to constrain the entire dynamic of Campi Flegrei from the first space mission equipped with a SAR sensor in 1992. To do this, the GeoSAR Laboratory of INGV processed SAR data acquired by ERS 1-2 (1992 - 2002), Envisat (2003 - 2010) and Cosmo-SkyMed (2011 – 2021) missions using the same technique, parameters and reference system. The retrieved outcomes in terms of InSAR ground velocity rate and displacement time series were validated by the measurements provided by precise levelling