Mt. Etna ground deformation detected by SISTEM approach using GPS data and the new generation of SAR sensors

ALOS L-band and COSMO-SkyMed X-band SAR data, referring to Mt. Etna has been acquired in the framework of SAR4Volcanoes research project funded by the Italian Space Agency (ASI). The project is carried out in the framework of a cooperation agreement between the Japan Aerospace Exploration Agency (JAXA) and ASI. The SAR data have been analyzed by using a time series approach, based on the SBAS technique. Thanks to the availability of geodetic in situ data collected on Mt. Etna, it was possible validate and integrate the SAR data with the GPS ground deformation data applying the SISTEM approach. The SISTEM approach simultaneously integrates all the available datasets (i.e. GPS displacement vectors on sparse benchmarks and SAR displacement maps), providing the high-resolution 3D displacement map by taking advantage of the positive features of each datasets, i.e. the high temporal and spatial resolution of the COSMO-SkyMed data, the good coherence of ALOS L-band interferometric data and the 3D displacements component provided by GPS with sub-cm accuracy level We apply the SISTEM method to compute 3D high-resolution surface displacement maps of Mt. Etna related to ground deformations referring to 2009-2010 time-span. The preliminary SISTEM results are consistent with the geophysical and volcanological background knowledge of the dynamic of Mt. Etna during the 2009-2010 period, showing a general inflation of the entire volcanic edifice coupled with the ESE sliding of the eastern and southeastern flank. The displacement pattern obtained by applying the SISTEM integration method provides an accurate spatial characterization of ground deformation and the proposed technique is promising for future studies on other volcanic areas, which are planned to study in the framework of SAR4Volcanoes project.