In September 2021, the La Fossa crater at Vulcano, in Italy, entered a new phase of unrest. We discuss a set of monitoring parameters included in the INGV surveillance network, which closely tracked the sequence of effects related to the crisis. The low-frequency local seismicity sharply increased, while the GPS and tiltmeter networks recorded the inflation of the cone, as an effect of fluid expansion in the hydrothermal system. Gravity variations were probably the effects of fast processes within shallow sources. The anomalies in soil CO₂ flux, fumarole temperature, and in plume SO₂ flux marked the strong increase in the vapor output from crater fumaroles. The signs of the impending crisis had been evident in the chemical and isotopic composition of fumarole gases since July 2021. These geochemical anomalies were clearly indicative of the enhanced input of gases from a magmatic source. In October, the massive degassing also influenced the areas at the base of the cone. In some areas, soil CO₂ degassing and the thermal aquifer recorded strong anomalies. By early November, the crisis reached its acme. Afterward, the monitored parameters started a slow and discontinuous decreasing trend although remaining, some of them, sensibly above the background for several months. The multidisciplinary approach proved decisive for the interpretation of the underlying processes acting in the different phases of the unrest, thus allowing a consistent evaluation of the multiple hazards.

This study was developed to carry out a comprehensive radiological assessment of natural radioactivity for river sediment samples from Calabria, southern Italy, and to define a baseline background for the area on a radiation map. In the studied area, elevated levels of natural radionuclides are expected, due to the outcropping acidic intrusive and metamorphic rocks from which the radioactive elements derive. To identify and quantify the natural radioisotopes, ninety river sediment samples from nine selected coastal sampling points (ten samples for each point) were collected as representative of the Ionian and the Tyrrhenian coastline of Calabria. The samples were analyzed using a gamma ray spectrometer equipped with a high-purity germanium (HPGe) detector. The values of mean activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K measured for the studied samples are (21.3 ± 6.3) Bq kg⁻¹, (30.3 ± 4.5) Bq kg⁻¹ and (849 ± 79) Bq kg⁻¹, respectively. The calculated radiological hazard indices showed average values of 63 nGy h⁻¹ (absorbed dose rate), 0.078 mSv y⁻¹ (effective dose outdoors), 0.111 mSv y⁻¹ (effective dose indoors), 63 Bq kg⁻¹ (radium equivalent), 0.35 (H_ex), 0.41 (H_in), 0.50 (activity concentration index) and 458 µSv y⁻¹ (Annual Gonadal Equivalent Dose, AGED). In order to delineate the spatial distribution of natural radionuclides on the radiological map and to identify the areas with low, medium and high radioactivity values, the Surfer 10 software was employed. Finally, the multivariate statistical analysis was performed to deduce the interdependency and any existing relationships between the radiological indices and the concentrations of the radionuclides. The results of this study, also compared with values of other locations of the Italian Peninsula characterized by similar local geological conditions, can be used as a baseline for future investigations about radioactivity background in the investigated area.

We constrained the origin and genetic environment of modern iron ooids (sand-sized grains with a core and external cortex of concentric laminae) providing new tools for the interpretation of their fossil counterparts as well as the analogous particles discovered on Mars. Here, we report an exceptional, unique finding of a still active deposit of submillimetric iron ooids, under formation at the seabed at a depth of 80 m over an area characterized by intense hydrothermal activity off Panarea, a volcanic island north of Sicily (Italy). An integrated analysis, carried out by X-ray Powder Diffraction, Environmental Scanning Electron Microscopy, X-ray Fluorescence and Raman spectroscopy reveals that Panarea ooids are deposited at the seafloor as concentric laminae of primary goethite around existing nuclei. The process is rapid, and driven by hydrothermal fluids as iron source. A sub-spherical, laminated structure resulted from constant agitation and by degassing of CO₂-dominated fluids through seafloor sediments. Our investigations point the hydrothermal processes as responsible for the generation of the Panarea ooids, which are neither diagenetic nor reworked. The presence of ooids at the seawater-sediments interface, in fact, highlights how their development and growth is still ongoing. The proposed results show a new process responsible for ooids formation and gain a new insight into the genesis of iron ooids deposits that are distributed at global scale in both modern and past sediments.

Within an E.U.-funded project, BESS (Pocket Beach Management and Remote Surveillance System), the notion of a geographic information system is an indispensable tool for managing the dynamics of georeferenced data and information for any form of territorial planning. This notion was further explored with the creation of a WebGIS portal that will allow local and regional stakeholders/authorities obtain an easy remote access tool to monitor the status of pocket beaches (PB) in the Maltese Archipelago and Sicily. In this paper, we provide a methodological approach for the implementation of a WebGIS necessary for very detailed dynamic mapping and visualization of geospatial coastal data; the description of the dataset necessary for the monitoring of coastal areas, especially the PBs; and a demonstration of a case study for the PBs of Sicily and Malta by using the methodology and the dataset used during the BESS project. Detailed steps involved in the creation of the WebGIS are presented. These include data preparation, data storage, and data publication and transformation into geo-services. With the help of different Open Geospatial Consortium protocols, the WebGIS displays different layers of information for 134 PBs including orthophotos, sedimentological/geomorphological beach characteristics, shoreline evolution, geometric and morphological parameters, shallow water bathymetry, and photographs of pocket beaches. The WebGIS allows not only for identifying, evaluating, and directing potential solutions to present and arising issues, but also enables public access and involvement. It reflects a platform for future local and regional coastal zone monitoring and management, by promoting public/private involvement in addressing coastal issues and providing local public administrations with an improved technology to monitor coastal changes and help better plan suitable interventions.

Terrestrial mud volcanoes (MVs) represent the surface expression of conduits tapping fluid and gas reservoirs in the deep subsurface. Such plumbing channels provide a direct, effective means to extract deep microbial communities fueled by geologically produced gases and fluids. The drivers accounting for the diversity and composition of these MV microbial communities, which are distributed over a wide geographic range, remain elusive. This study characterized the variation in microbial communities in 15 terrestrial MVs across a distance of ∼ 10 000 km on the Eurasian continent to test the validity of distance control and physiochemical factors in explaining biogeographic patterns. Our analyses yielded diverse community compositions with a total of 28 928 amplicon sequence variances (ASVs) taxonomically assigned to 73 phyla. While no true cosmopolitan member was found, ∼ 85 % of ASVs were confined within a single MV. Community variance between MVs appeared to be higher and more stochastically controlled than within MVs, generating a slope of the distance–decay relationship exceeding those for marine seeps and MVs as well as seawater columns. For comparison, physiochemical parameters explained 12 % of community variance, with the chloride concentration being the most influential factor. Overall, the apparent lack of fluid exchange renders terrestrial MVs a patchy habitat, with microbiomes diverging stochastically with distance and consisting of dispersal-limited colonists that are highly adapted to the local environmental context.