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We investigate the 24–27 December 2018 eruption of Mount Etna occurred from fissures located on the volcano eastern flank and accompanied by a seismic swarm, which was triggered by the magma intrusion and continued for weeks after the end of the eruption. Moreover, this swarm involved some of the shallow volcano‐tectonic structures located on the Mount Etna flanks and culminated on 26 December with the strongest event (ML4.8), occurred along the Fiandaca Fault. In this work, we analyze seismological data and Sentinel‐1 Differential Interferometric Synthetic Aperture Radar (DInSAR) measurements, the latter inverted through analytical modeling. Our results suggest that a dike source intruded, promoting the opening of the eruptive fissures fed by a shallower dike. Moreover, our findings indicate that the activation of faults in different sectors of the volcano may be considered as a response to accommodate the deformations induced by the magma volumes injection. We investigate the ground displacements and the 3D source geometry of the December 2018 Mount Etna (Italy) volcano‐tectonic crisisDInSAR data obtained from SAR data pairs collected by Sentinel‐1 have been inverted through analytical modelingOur results suggest the presence of two volcanic sources: a shallow dike and a deeper one associated with a long‐term seismic swarm

La Fossa Caldera at Vulcano (Italy) has been showing signs of unrest since September 2021. To investigate this phenomenon, we conducted an analysis of geodetic and seismological data from July to December 2021. In particular, we analyzed Multi Temporal Interferometric Synthetic Aperture Radar and Global Navigation Satellite System data, showing a pronounced elliptical uplift signal, which we elaborated using analytical source modeling. Additionally, seismic data were used to identify seismicity associated with hydrothermal system activity and assess its temporal evolution. The results indicate that the observed deformation is consistent with the expansion of the hydrothermal system within the La Fossa Caldera. These findings align with the analysis of seismic data, revealing signals indicative of hydrothermal activity, such as Very Long Period events. The results suggest that the ongoing phenomenon since 2021 represents a hydrothermal unrest, similar to the one observed during the late 1970s to early 1990s. La Fossa Caldera at Vulcano Island, part of the Aeolian Islands archipelago in Italy, has shown an increased volcanic activity since September 2021. This activity is characterized by an increase in fumarole temperatures, massive gas emissions, as well as a marked uplift of the crater area, accompanied by an increase in seismicity. To investigate the nature of these phenomena, an analysis of ground deformation data obtained from Multi Temporal Interferometric Synthetic Aperture Radar and Global Navigation Satellite System measurements is presented. Additionally, a detailed analysis of data recorded by the seismic network on Vulcano Island has been conducted. The results indicate that these anomalies can be attributed to the expansion of the hydrothermal system, a phenomenon previously observed in the late 1970s and early 1990s. Multi Temporal Interferometric Synthetic Aperture Radar enabled investigating localized ground deformation in the La Fossa CalderaThe analysis of local seismicity indicates it is associated with the injection of fluids into conduit‐like structuresThe modeled source of ground deformation associated with the 2021 unrest is consistent with the pressurization of the hydrothermal system Multi Temporal Interferometric Synthetic Aperture Radar enabled investigating localized ground deformation in the La Fossa Caldera The analysis of local seismicity indicates it is associated with the injection of fluids into conduit‐like structures The modeled source of ground deformation associated with the 2021 unrest is consistent with the pressurization of the hydrothermal system

The causative source of the first damaging earthquake instrumentally recorded in the Island of Ischia, occurred on 21 August 2017, has been studied through a multiparametric geophysical approach. In order to investigate the source geometry and kinematics we exploit seismological, Global Positioning System, and Sentinel-1 and COSMO-SkyMed differential interferometric synthetic aperture radar coseismic measurements. Our results indicate that the retrieved solutions from the geodetic data modeling and the seismological data are plausible; in particular, the best fit solution consists of an E-W striking, south dipping normal fault, with its center located at a depth of 800 m. Moreover, the retrieved causative fault is consistent with the rheological stratification of the crust in this zone. This study allows us to improve the knowledge of the volcano-tectonic processes occurring on the Island, which is crucial for a better assessment of the seismic risk in the area. Investigation of the ground deformation and source geometry of the 2017 Ischia Island earthquake (Italy) is discussedThe available seismological, GPS, and DInSAR data permit to investigate the causative fault and define its geometry and kinematicsThe results suggest that the rheology properties of the crust beneath the Ischia Island have an influence on the volcano-tectonic processes

We investigate a large geodetic data set of interferometric synthetic aperture radar (InSAR) and GPS measurements to determine the source parameters for the three main shocks of the 2016 Central Italy earthquake sequence on 24 August and 26 and 30 October (Mw6.1, 5.9, and 6.5, respectively). Our preferred model is consistent with the activation of four main coseismic asperities belonging to the SW dipping normal fault system associated with the Mount Gorzano‐Mount Vettore‐Mount Bove alignment. Additional slip, equivalent to a Mw~ 6.1–6.2 earthquake, on a secondary (1) NE dipping antithetic fault and/or (2) on a WNW dipping low‐angle fault in the hanging wall of the main system is required to better reproduce the complex deformation pattern associated with the greatest seismic event (the Mw6.5 earthquake). The recognition of ancillary faults involved in the sequence suggests a complex interaction in the activated crustal volume between the main normal faults and the secondary structures and a partitioning of strain release. Coseismic ground deformation of the 2016 Central Italy earthquake sequence measured with InSAR and GPS dataAt least four main normal fault segments played an active role in the sequenceAntithetic faults and/or preexisting compressional structures may have been reactivated during the sequence with extensional kinematics

We present an efficient solution to mitigate phase unwrapping (PhU) errors that can affect a sequence of multi-temporal differential synthetic aperture radar (SAR) interferograms. To this aim, we propose a strategy that, starting from a properly chosen network of differential interferograms, complements PhU operations with an advanced multi-temporal region-growing (RG) procedure that exploits the space-time relationships among the computed interferograms. In particular, the proposed method implements an iterative procedure that, at each step, allows correcting a sequence of previously unwrapped interferograms at one selected pixel, namely candidate pixel, by exploiting the (unwrapped) phase values at its neighbouring ‘seed’ pixels (i.e. the ones already correctly unwrapped). Following their estimation, the unwrapped phases are then used to retrieve surface deformation products, such as mean deformation velocity maps and displacement time series, through (advanced) small baseline differential SAR interferometry (DInSAR) techniques. The effectiveness of the presented RG PhU algorithm is demonstrated by analysing a data set of SAR images acquired by the European Remote Sensing (ERS)-1/2 sensors over the megacity area of Istanbul, Turkey.

We provide new insights into the two main seismic events that occurred in 2012 in the Emilia region, Italy. We extend the results from previous studies based on analytical inversion modeling of GPS and RADARSAT‐1 InSAR measurements by exploiting RADARSAT‐2 data. Moreover, we benefit from the available large amount of geological and geophysical information through finite element method (FEM) modeling implemented in a structural‐mechanical context to investigate the impact of known buried structures on the modulation of the ground deformation field. We find that the displacement pattern associated with the 20 May event is consistent with the activation of a single fault segment of the inner Ferrara thrust, in good agreement with the analytical solution. In contrast, the interpretation of the 29 May episode requires the activation of three different fault segments and a block roto‐translation of the Mirandola anticline. The proposed FEM‐based methodology is applicable to other seismic areas where the complexity of buried structures is known and plays a fundamental role in the modulation of the associated surface deformation pattern. Detection of active seismogenic structures responsible for ground deformationEvaluate the role of tectonic constrain on the modulation of ground deformationProvide a detailed characterization of the rock failure mechanisms

We investigate the 19 September 2021 eruption of the Cumbre Vieja volcano (La Palma, Canary Islands, Spain). In particular, we analyze the Differential Interferometric Synthetic Aperture Radar (DInSAR) measurements obtained by processing Sentinel‐1 images acquired from both ascending and descending orbits. First, we show the importance, for oceanic islands like La Palma, of investigating DInSAR products retrieved from time series, instead of single interferograms, to effectively remove possible atmospheric artifacts within the displacement measurements. Subsequently, we invert the retrieved data through analytical modeling. Our results highlight that a sill–like source was active in the pre–eruptive phase (8–16 September), whereas the action of two dikes prevailed during the co‐eruptive phase (17–22 September). This evolution suggests a process of magma rising through a network of interconnected sills and dikes. The seismicity, that preceded and accompanied the onset of the eruption, is consistent with our findings. Since 19 September 2021, an intense eruptive activity has begun at Cumbre Vieja volcano (La Palma, Canary archipelago, Spain), causing huge social and economic damage. The eruption was preceded and accompanied by numerous phenomena, such as gas emissions and seismic activity. In this work, we exploit the Differential Interferometric Synthetic Aperture Radar (DInSAR) measurements, obtained by processing Sentinel‐1 images, to quantify the retrieved pre‐ and co‐eruptive deformation patterns. In particular, this eruption provided us the opportunity to show the importance, for oceanic islands like La Palma, of investigating DInSAR products retrieved from time series, instead of conventional single interferograms, to effectively remove possible atmospheric artifacts within the displacement measurements. Subsequently, we invert the retrieved surface deformation measurements to investigate the geometries of the volcanic sources responsible for the observed deformations. Our results show the evolution of this eruptive phenomenon from the pre‐to the co‐eruptive phases, suggesting that a complex network of sills and dikes has allowed the magma rising. Moreover, our findings are in good agreement with the recorded seismicity and several geophysical evidence. We retrieve the pre‐ and co‐eruptive deformation patterns of Cumbre Vieja volcano through an advanced processing of Sentinel‐1 radar dataWe show that a sill‐like source was active in the pre‐eruptive phase, whereas the action of two dikes prevailed in the co‐eruptive oneThe retrieved sources are consistent with magma rising through a network of interconnected sills and dikes, and the seismicity evolution We retrieve the pre‐ and co‐eruptive deformation patterns of Cumbre Vieja volcano through an advanced processing of Sentinel‐1 radar data We show that a sill‐like source was active in the pre‐eruptive phase, whereas the action of two dikes prevailed in the co‐eruptive one The retrieved sources are consistent with magma rising through a network of interconnected sills and dikes, and the seismicity evolution

We investigate the ground deformation and source geometry of the 2016 Amatrice earthquake (Central Italy) by exploiting ALOS2 and Sentinel‐1 coseismic differential interferometric synthetic aperture radar (DInSAR) measurements. They reveal two NNW‐SSE striking surface deformation lobes, which could be the effect of two distinct faults or the rupture propagation of a single fault. We examine both cases through a single and a double dislocation planar source. Subsequently, we extend our analysis by applying a 3‐D finite elements approach jointly exploiting DInSAR measurements and an independent, structurally constrained, 3‐D fault model. This model is based on a double fault system including the two northern Gorzano and Redentore‐Vettoretto faults (NGF and RVF) which merge into a single WSW dipping fault surface at the hypocentral depth (8 km). The retrieved best fit coseismic surface deformation pattern well supports the exploited structural model. The maximum displacements occur at 5–7 km depth, reaching 90 cm on the RVF footwall and 80 cm on the NGF hanging wall. The von Mises stress field confirms the retrieved seismogenic scenario. Investigation of the ground deformation and source geometry of the 2016 Amatrice earthquake (Central Italy)Coseismic displacements modeling through a 3‐D finite elements approach jointly exploiting DInSAR measurements and a 3‐D fault modelEvidence of a bilateral rupture propagating along two en echelon normal faults conjoined at the hypocenter