InSAR Displacement Evolution of Emplaced Lava Flows: New Insights into the December 2018 Etna Unrest

On 24 December 2018 a new lateral eruption of Mt. Etna volcano began. The phenomenon produced an intense seismic swarm, strong gaseous emissions from the summit craters and a well-defined lava flow, emplaced on the southwestern portion of the Valle del Bove depression. During the following paroxysm occurred on 29 May 2019, a new lava flow partially covered the previous ones. Aiming to evaluate the effects over time that the emplacement of lava flows produces over the volcanic structure, here we exploited a multidisciplinary approach, comprising both optical (Sentinel-2) and radar (Sentinel-1 and Cosmo-SkyMed) satellite data, processed through different remote sensing techniques. In detail, Sentinel-2 data allowed to retrieve the lava flows boundaries, Sentinel-1 data permitted to reconstruct ground displacement maps and related time series during the January 2016 – July 2021 time span whilst Cosmo-SkyMed ones were used to estimate the topographic changes caused by the lava emplacement.