Nel 1904, il professor Francesco Cavani, su incarico del Comune di Bologna, fu chiamato a valutare la stabilità della Torre Garisenda. A tal fine, sviluppò un innovativo sistema di monitoraggio, basato su un filo a piombo fissato a circa 40 metri di altezza sulla parete Sud e su cannocchiali specializzati, dotati di un doppio sistema di lenti e fuochi, in grado di rilevare spostamenti con una precisione fino a un ventesimo di millimetro. Le tavole allegate alla sua relazione presentano in dettaglio i dati di monitoraggio, comprensivi delle serie temporali degli spostamenti verso Est e Nord, rappresentate in scala ingrandita 20:1. In questo studio, le serie originali sono state digitalizzate, scalate ed esportate per essere analizzate con metodi moderni. L’obiettivo è quello di estrarre informazioni sulle caratteristiche dinamiche del movimento della torre, sia nel dominio del tempo che in quello delle frequenze. I risultati ottenuti mettono in evidenza le oscillazioni e le relative ampiezze, offrendo una lettura moderna e aggiornata del comportamento dinamico della struttura a oltre un secolo di distanza. Questo lavoro si propone come strumento per divulgare alcune informazioni di base sul comportamento della torre nel passato, al fine di valutare, in studi futuri, eventuali cambiamenti significativi nella caratterizzazione cinematica dei suoi movimenti. Inoltre si annunciano futuri sviluppi per aumentare la comprensione dei limiti spaziali e temporali dei risultati in considerazione delle imperfezioni dei grafici storici.

We present the deployment and performance of 17 temporary broadband seismic stations installed in Northern Italy and Sardinia as part of the AdriaArray project. These stations aim to densify the national seismic network, especially in areas with historically sparse coverage such as the Po Plain and Sardinia. We describe here the network design and site selection that follow high‑quality standards developed during previous large‑scale European seismic experiments. Despite challenging environmental and anthropogenic conditions, the stations recorded high‑quality data, enabling both local and teleseismic event detection. We analyze the seismic noise characteristics across the network using probabilistic power spectral densities and observe that stations installed in sedimentary basins typically show higher noise levels at short periods, while stations in rock sites – especially in Sardinia – generally perform better. The use of different sensor types and installation methods also influences noise behavior, particularly in the long‑period components. Despite the diverse conditions, the stations allow for the recording of both local and teleseismic events. The addition of the 4P stations improves the network’s detection threshold by approximately 0.4 magnitude units in Sardinia and 0.2 in the North Italy. The open‑access data from this deployment contribute to AdriaArray’s broader goals of advancing seismic imaging and geodynamic interpretation in the Mediterranean region.

Vulcano Island has experienced recurrent historical eruptive activity from the La Fossa and Vulcanello cones, including predominantly phreatomagmatic, Vulcanian, and occasionally Strombolian eruptions. It has also produced several effusive events and phreatic explosions. Despite extensive geological investigations and numerous radiometric and palaeomagnetic age determinations, significant gaps persist in the chronology and source attribution of historical eruptions. These gaps largely reflect stratigraphic complexity and the limited availability of reliable tephrostratigraphic markers. This study presents a critical reassessment of the eruptive chronology and vent locations of the La Fossa and Vulcanello cones from the 4th century BCE to the 18th century CE. We employ a multidisciplinary approach integrating historiographical analysis with recent volcanological and stratigraphic data. A systematic review of historical texts and iconographic sources was conducted, using rigorous philological criteria, to assess their reliability and their temporal and spatial resolution independently of existing volcanological interpretations. Key results include: (1) The identification of the initial emergence of the Vulcanello cone and associated lava platform between 183 and 126 BCE, and its subsequent stabilization in later centuries; (2) The reconstruction of the definitive formation of the isthmus connecting Vulcanello to the rest of Vulcano, attributed to the progressive accumulation of eruptive material from the La Fossa cone. This likely occurred at the beginning of the 16th century and culminated with the 1525–1526 CE eruption; (3) The absence of conclusive textual evidence for modern-era eruptions at the Forgia Vecchia crater, despite geological indicators of older explosive phases during the early development of the La Fossa cone; (4) The refinement of the chronology of the 18th-century Pietre Cotte eruptive cycle, with emplacement of a rhyolitic lava flow in 1739 CE and an associated pumice fallout in 1771 CE, each emitted from different summit vents of the La Fossa cone. The study outlines five major eruptions or eruptive cycles exceeding the typical intensity and magnitude of vulcanian-type explosions. These occurred in the late 4th century BCE, 1444 CE, 1525–26 CE, 1739 CE, and 1771 CE. No major phreatic eruptions are documented in historical sources, aside from the well known and historiographically transparent Breccia di Commenda eruption. However, geological evidence indicates that numerous (minor) phreatic explosions occurred during initial vent-opening phases. These findings demonstrate the value of historical sources in reconstructing Vulcano’s eruptive history and underline their potential to enhance the temporal resolution of probabilistic hazard scenarios for the island.

The transition from oceanic subduction to continental collision and, eventually, to delamination is thought to control dynamics, magmatism/metamorphism, and tectonic/sedimentation style in orogens. We propose for the first time that the alternation of slow and fast orogenic wedge advance and backarc opening in the retreating Apennines subduction zone (central Mediterranean area) was controlled by the transition from oceanic subduction to soft-collision (subduction of hyperextended continental lithosphere), evolving to hard-collision (subduction of the necking domain), and eventually to delamination. The coupling between slab dynamics and the evolution of the orogen is revealed by an unprecedented joint analysis of magmatism/metamorphism, of timing and rate of migration of forebulging, thrusting, and backarc extension and of seismic heterogeneities in the slab. Oceanic subduction and soft-continental collision, testified by high pressure-low temperature metamorphism, was characterized by fast orogenic and backarc extension migration, fast rotation of Corsica and Sardinia and vigorous magmatism. Low shear velocity anomalies observed in along-dip tomographic profiles across the Apennines are interpreted as signatures of slab damage events associated with the diachronous (at 21 Ma in the Northern and at 18 Ma in the Central/Southern Apennines) underthrusting of the necking domain of Adria in the Northern and Central-Southern Apennines. This hard-collision stage was characterized by slow orogenic wedge advance and backarc opening. The heating and weakening of the subducting continental crust produced by hard-collision promoted the transition from continental subduction to delamination of the Adria lithosphere. This process occurred at ca. 9 Ma and led to a relocalization of the subduction interface from the base of the sedimentary cover into the ductile middle crust and was associated with a renewal of fast orogenic wedge advance and backarc opening.

The movement of large masses on the Earth’s surface, including landslides or debris flows, transfers energy to the ground, inducing both permanent and transient deformation. This gener- ates measurable motion and seismic radiation that can be detected by proximal seismic networks. On November 26, 2022, during heavy rainfall, several debris flows inundated the northern slope of the active volcanic island of Ischia in southern Italy, causing fatalities and extensive damage. The island of Ischia is one of the most land- slide-prone localities in Italy. It has already suffered comparable, even larger, events over the past two centuries, and with a popula- tion of around 60,000 and more than 300,000 tourists per year, it is considered a high natural risk zone. In this study, we performed seismological analyses over an extended range of frequencies and scales, using broadband data recorded by the local permanent seis- mic network, to study the dynamics of the November 26, 2022, event and to quantitatively characterise its evolution over time. Unlike post-event static surveys, a major advantage of the seismological approach is its ability to track the progression of the debris flow motion from the instant of the initial detachment. Our analyses allowed us to estimate the spatial and temporal origin of the rock detachments, the mass of the flowing material, the size of the coarse boulders, the speed at which the landslide approached the nearest seismic station, and the impacting overpressure that caused the most severe damage. These results further demonstrate that spe- cifically designed instrumental (seismic and tiltmetric) networks represent an essential tool for real-time monitoring and for activat- ing early warning systems prior to potential damage to inhabited localities.

Swarm‐like seismicity manifests as earthquake clusters driven by aseismic transients. The investigation of the mechanisms behind their occurrence is generally based on automatic detection and characterization of swarm‐like clusters. In this study, we investigate four different (de‐)clustering algorithms to identify earthquake clusters, and then classify these clusters as either swarm‐like or mainshock–aftershocks sequences. The classification uses the clusters’ distribution of seismic moment over time, quantified by standardized central moments. Synthetic catalogs from an epidemic‐type aftershock sequence model are used to establish confidence bounds for swarm classification. The workflow is applied to the swarm‐dominated regions Húsavík–Flatey fault, Iceland, and Pollino range, Italy. Our workflow effectively detects/classifies earthquake clusters, but their inherent variability in duration and seismic moment release can bias automated swarm/mainshock–aftershocks labeling. The results provide benchmarks for future swarm‐like seismicity analyses, highlighting the importance of a posteriori careful inspection of clusters to understand the underlying physical mechanisms.

In a recent work, we tested the ability to compute earthquake parameters (location and magnitude) using citizen testimonies collected by the European-Mediterranean Seismological Centre (EMSC). Each intensity estimated by individual non-professional users of the LastQuake smartphone application is indicated as an individual data point (IDP). Each IDP is archived by EMSC with a time stamp, allowing the calculation of the time delay from the earthquake origin time. To use IDPs as classic intensities, i.e. macroseismic data points (MDPs), identifying damage at the scale of towns or cities, they must be grouped into spatial clusters, which are then processed by the BOXER code to locate and size global earthquakes. A retrospective analysis on a dataset of more than 15,000 events collected over the past 10 years shows that the procedure can provide reliable parameters and that the results depend on the geographical area and improve over time and as the number of available IDPs/MDPs increases. The key question is whether early IDPs/MDPs can quickly provide reliable parameters (location and magnitude) for users and stakeholders (e.g. the civil protection agencies). Using clustering methods that statistically provide, on average, the best agreement with instrumental data, we tested some predefined time intervals within which to group the available IDPs into MDPs. We then applied the BOXER code to these MDPs, evaluating the agreement with the final instrumental parameters. Results confirm that reliability increases with the number and distribution of MDPs, strictly dependent on the number and distribution of available IDPs. This retrospective analysis demonstrates the effectiveness of the approach and its potential to quickly provide parameters for future real-time applications. The method may offer a reliable and rapid tool to support emergency response, improving as more IDPs/MDPs are collected.