The first seismo-volcanological observatory in the anglophone Caribbean was established on Montserrat in 1936, in response to a volcano-seismic crisis that began with repeated felt events in 1933. Staff at Montserrat's agricultural office began routinely recording earthquake shocks in 1934. In 1936, following a scientific expedition dispatched by the Royal Society, an observatory was established at the Grove Botanical Station, Plymouth. This was run by volcano-seismic observers who managed an instrumental network, and monitored gas and steam emissions and air quality. The observatory functioned until 1946. We reconstruct the decision-making and evolution of the instrument networks as the observatory was established, and highlight the personnel involved, including the first female seismo-volcanic observer on Montserrat, Greta Scotland. Observations from the 1930s crisis emphasise the persistent seismicity and gas emissions associated with this extended episode of unrest, and suggest that there were minor phreatic explosions at the height of the crisis. We draw parallels with long-term observations of the activity of the Soufrière Hills Volcano since the 1990s.

Stromboli is a unique open-conduit mafic volcano known for persistent Strombolian eruptions of highly porphyritic (HP) basalticshoshonite scoria. Stronger paroxysmal explosions occur once or twice per decade, ejecting low porphyritic (LP) golden pumice from deeper volatile-rich magma. The July 3rd, 2019, paroxysm showed features of a Vulcanian eruption—supersonic blast, ballistic ejection, and pyroclastic flows—despite Stromboli’s open-conduit basaltic nature. Textural analysis suggests that LP pyroclasts formed via rapid decompression, fragmentation, and quenching. This event likely resulted from shallow HP-filled conduit pressurization and failure triggered by a rising large gas slug. This caused top-down decompression, evacuating both HP and deeper LP magma. The proposed “basaltic Vulcanian” model better fits geophysical data than the traditional deep LP magma ascent model.

The Carrán-Los Venados volcanic field in southern Chile comprises small basaltic eruption centres of Holocene to historical ages. These centres are atop extensive, basaltic flows that erupted during late glacial or early postglacial times (< 14ka), marking a dramatic change in eruption style over a short space of time. Differences in trace element characteristics and U-series isotopes point to a dampened subduction influence in the melting environment of the older Basal Lavas. Th isotopes point to higher melting rates and more dominant decompression melting, which may be related to the deglaciation of southern Chile at this time. Olivine textures and chemistry suggest longer storage times for the Basal Lavas compared to the Holocene tephras. The historic eruptions have relatively homogeneous whole rock compositions, suggesting the development of a storage system in the lower crust. This may be the beginning of a thermal environment more akin to those of nearby stratovolcanoes.

We introduce the Volcanology Infrastructure for Computational Tools and Resources (VICTOR), a cloud-based cyberinfrastructure designed to modernize computational workflows and data access in volcanology. Built around a scalable JupyterHub environment, VICTOR provides users with an array of pre-installed modeling tools, remote sensing data access workflows, geochemical calculators, and the pyVICTOR utility library for geospatial and visualization tasks. The platform drives educational efforts through courses, modular teaching materials, and multilingual documentation. VICTOR promotes open science by making tools findable, accessible, interoperable, and reproducible (FAIR) and enables innovative workflows including multi-model intercomparisons and inversion schemes. We describe its architecture, current tool suite, community engagement activities, and plans for model coupling, machine learning integration, and expanded observatory support. VICTOR exemplifies a community-driven approach to infrastructure that empowers researchers, educators, and stakeholders in volcanic hazard science.

This study investigates sulfur dioxide (SO2) emissions from Stromboli’s explosive activity using ground-based remote sensing techniques. We analyze the SO2 mass derived from ultraviolet (UV) and thermal infrared (TIR) cameras, alongside explosion parameters and emitted products obtained from high-frequency thermal imaging. Our dataset (May 23–24, 2023) includes 49 explosions ranging from gas-dominated (Type 0) to bomb-dominated (Type 1) and ash-rich (Type 2). During non-explosive periods, UV and TIR SO2 masses are generally comparable, whereas explosions show systematic TIR overestimation relative to UV. The TIR/UV deviation scales with plume temperature and eruption type, reflecting TIR sensitivity to thermal radiation and ash scattering, while UV retrievals remain largely temperature-independent. Our results emphasize the need for temperature-based corrections in TIR retrievals, and support integrated multi-sensor approaches for robust, real-time monitoring of volcanic gas emissions.

Most high-temperature geothermal areas have a similar resistivity signature, reflecting the alteration state of the system, as is the case for the Reykjanes high temperature system. A geothermal system has an intermediate resistivity core (30–100 Ωm), overlain by a low resistivity cap (1–10 Ωm); at Reykjanes this cap reaches the surface. Hence, the study of the shallow subsurface can provide insights into the state of the system and deeper processes. Traditionally, geothermal systems are studied using electromagnetic methods, which have a large penetration depth but a low resolution. This is sufficient to characterize the system, but capturing dynamics requires sufficiently large changes and careful survey design. In this study, we explore the potential of the combined use of three geo-electric methods: electrical resistivity tomography (ERT), induced polarization (IP), and self-potential (SP), to characterize the shallow (<50 m) subsurface at Reykjanes and interpret it in a dynamic context, without the need for repeated measurements. The observed resistivity signature reflects the typical resistivity distribution known at the site. The addition of SP allows for the identification of active geothermal processes, which are highly variable and localized. The IP signal revealed a shallow (<20 m) sealing structure, prohibiting fluid and gas migration, causing the absence of hydrothermal surface expressions. Such a seal can be potentially hazardous due to over-pressurization and could not be identified from resistivity imaging alone. Here we demonstrate that shallow structures can act as a proxy for deep processes. Furthermore, we show that the combination of the tree methods is invaluable in studying these complex systems and recommend this for future studies.

Monitoring the spatio-temporal evolution of fumarolic activity is key to understanding volcanic unrest at dormant volcanoes. Here, we present the results of periodic gas surveys conducted at La Fossa (Vulcano Island, Italy) between 2021 and 2024, in which a portable Multi-GAS instrument is used to map the spatial variations in gas composition across the fumarolic field. We identify substantial spatio-temporal changes in gas composition. The crater rim fumaroles exhibit the highest CO2, SO2, H2S, H2 concentrations and stable, relatively low CO2/SO2 ratios (around 20–30), all indicative of a larger magmatic contribution. In contrast, the inner crater fumaroles display more variable and generally higher CO2/SO2 ratios, indicating a larger hydrothermal influence. These data, combined with infrared thermal imaging and SO2 flux results, are indicative of a volcanic unrest that, after having reached its climax in late 2021, has gradually vanished since, although not fully returning to pre-unrest conditions

Understanding volcanic processes including eruption mechanisms depends on knowledge of temperature and chemical compo- sition (thermochemical structure) of the crust and the upper mantle. This study applies an integrated geophysical-petrological modeling constrained by available seismic information to study the crustal and upper mantle thermochemical heterogeneities in two active volcanoes, Nemrut and Suphan (East Anatolia). The results reveal significant assemblage of basalts at depth beneath Nemrut and Suphan volcanoes. The assemblage of basalt is correlated with considerable lithospheric thinning/disappearance. Predicting geoid height anomaly and fitting gravity data including free-air and Bouguer anomalies supports the presence of the basaltic body as well as the modeled thermochemical structure. This study also implies that the crustal density structure can be biased in the presence of the significant sub-lithospheric heterogeneities. The temperature of the Moho is ~1118 °C, while the temperature of the underlying asthenosphere exceeds 1420 °C, beneath Nemrut and Suphan. The intense seismicity and focal mechanism type (strike-slip and thrust) suggests the magma differentiation and ascent of multiple magma intrusions beneath Nemrut and Suphan, which is supported by asthenospheric and extensional tectonics. Magmatism in East Anatolia is likely to be associated with a low-degree of anhydrous melting of the asthenosphere while hydrous melting is unlikely.

VolFe is an open-source flexible and adaptable thermodynamic framework in Python for calculating the equilibrium composition of melt and vapour. VolFe considers basaltic through rhyolitic melts including the volatiles carbon, hydrogen, sulfur, and the noble gases. VolFe models both reduced and oxidised systems due to the range of melt and vapour species included. Hence, VolFe is applicable to terrestrial (e.g. mid-ocean ridges to arcs) and extra-terrestrial (e.g. the Moon and Mars) systems. New parameterisations of “model-dependent variables” (e.g. volatile solubility functions, sulfide-saturation conditions, fugacity coefficients, etc.) can be added as new experimental studies come out, enhancing VolFe's future applicability. The main calculations currently included in VolFe are the pressure of vapour-saturation based on the dissolved volatile content of melts; H2O-CO2 isobars, open- and closed-system degassing and regassing; an oxybarometer based on the melt sulfur content; and uncertainty propagation of the input melt compositions on calculation outputs. As an example, we apply VolFe to melt inclusion and submarine pillow glass data from the Marianas arc.

There is a lack of understanding around the impacts and responses of communities receiving hazard and risk information during volcanic crises, but social media posts may be able to provide valuable insights. Using 7434 posts in a local residents’ Facebook group during the 2018 Kīlauea eruption, we track changes in social behaviour and emotional response. Eruption-related posts are dominated by information sharing and community observations. Sentiment and reaction analyses reveal an overall positive response, partly related to community support actions and local culture, despite the substantial detrimental eruption impacts. Temporal trends in the content of, and interactions with, posts can be linked to events during the eruption and actions taken by authorities, while the frequency of eruption posts decreases during hurricanes, indicating a shift in perceived risk in the community. Overall, results suggest social sensing with Facebook posts can provide insights on social actions and reactions during volcanic crises, but results differ from analyses of Twitter posts for the same event. More development of the techniques will be vital to gain full advantage of this promising approach.