EGMS-based comparative analysis of ground deformation before and after volcanic eruptions of Etna and Stromboli (2019-2023)

Ground deformation monitoring is a key tool for understanding volcanic processes, particularly in settings where in situ observations are limited or unavailable. This study presents a comparative analysis of surface deformation associated with major eruptive events at Mount Etna and Stromboli between 2019 and 2023 using InSAR-derived satellite data.

The primary objective is to evaluate whether documented eruptive events correspond to detectable ground motion and classify deformation patterns before, during and after these events. 

Eruptive events were selected based on records from the Smithsonian’s Global Volcanism Program, ensuring a reliable event catalogue.

The analysis is based on data obtained from the European Ground Motion Service (EGMS).

 

A set of measurement points located on and around both volcanoes was used to analyse how deformation changes in space and over time. For each eruptive event, time windows for pre-, syn- and post-eruptive stages were defined, allowing for comparative analysis of trends and amplitudes. In addition to event-based analysis, high-amplitude deformation anomalies were also identified and evaluated in terms of their correspondence with known eruptions. Sentinel-2 optical imagery supported the interpretation of surface changes.

Large-scale signals are well captured, while small or rapid processes may be missed or undersampled. Integrating InSAR time series with optical data improves interpretation and supports applications in planetary science for analysing surface deformation on other planetary bodies.