Lava dome collapse hazards are intimately linked with their morphology and internal structure. We present new lava dome emplacement models that use calibrated rock strengths and allow material behaviour to be simulated for three distinct units: (1) a ductile, fluid core; (2) a solid upper carapace; and (3) disaggregated talus slopes. We first show that relative proportions of solid and disaggregated

Kambalny is the southernmost volcano in the Kamchatka Peninsula. After a long repose stage, on March 24, 2017, it produced a strong phreatic eruption, which ejected an ash cloud to the distance of up to 1000 km. In summer 2018, we deployed ten seismic stations in the vicinity of Kambalny for one year. Data from this network and the only permanent station located at ~20 km from the volcano provided

Retrospective eruption characterization is valuable for advancing our understanding of volcanic systems and evaluating our observational capabilities, especially with remote technologies (defined here as a space-borne system or non-local, ground-based instrumentation which include regional and remote infrasound sensors). In June 2019, the open-system Ulawun volcano, Papua New Guinea, produced a VEI

The western slope of Cerro Domuyo in northern Patagonia is characterized by thermal springs with boiling waters, Quaternary silicic domes, and pyroclastic deposits that suggest the existence of a geothermal reservoir. According to geochemical studies, the reservoir may have a temperature of 220 °C and one of the largest advective heat fluxes reported for a continental volcanic center. In this paper

The youngest (last 1500 years) volcanic eruptions of Lipari, within the Aeolian Archipelago, produced the prominent pumice cone of Monte Pilato and the obsidian lava flows of Rocche Rosse and Forgia Vecchia, concentrated in the north-eastern sector of the island as well as highly dispersed white-coloured, fine-grained tephra layers of rhyolitic composition in terrestrial and marine settings on the

There are currently no reliable methods to determine rock physical and mechanical properties that are not labor or resource intensive, especially at the scale of volcanoes. Using mineralogical-physical-mechanical relationships, we suggest it is possible to derive rock properties from rapid, non-invasive reflectance spectroscopy measurements. To demonstrate this potential, we correlate the physical

Siliceous sinter is formed by biogenic and abiogenic opal deposition around hot springs and geysers. Using Structure-from-Motion photogrammetry we generated three-dimensional models of Giant and Castle Geysers from the Upper Geyser Basin of Yellowstone National Park. We use these models to calculate an approximate mass of sinter for each (~2 and ~ 5 kton, respectively) and estimate a range of plausible

The Santorini-Amorgos zone is an area rich in microseismicity at the center of the Hellenic volcanic arc. The microseismicity of the zone is distributed along the Santorini-Amorgos ridge and Kolumbo submarine volcano. In this study, we utilized crustal events that were recorded by temporary networks during September 2002 to July 2004 and October 2005 to March 2007, and also by the permanent network

This compilation re-visits the May 18, 1980 Plinian eruption sequence of Mount St. Helens and correlates new and existing observations and measurements for a revised narrative of when and how eruption behavior changes occurred. It presents new observations of vesicle textures in white pumice and analyses of lithic materials that are correlated with observed eruption behavior. These and the compositional

Volcano-tectonic (VT) earthquake swarms are usual precursors to volcanic eruptions and their dynamic phenomenologies are an invaluable eruption forecasting tool. A power-law relationship between cumulative seismic moment release and intrusion volume has been proposed for both well injection sites and VT swarms. Here we compile data from 17 geodetically-studied VT swarms and use a Bayesian methodology

The Harrat Rahat (HR) is the largest harrat in the Large Igneous Province in Saudi Arabia. Evolution of HR is enigmatic; two main debated postulates are the Red Sea rift margin volcanism vis-a-vis the Afar plume activity. Our objective in the present study is to investigate the rheological parameters for the crustal columns beneath the HR; computed from Receiver Function analysis results based on 11

For accurate and timely information on the evolving state of our volcanoes we need reliable short-term forecasts. These forecasts directly impact crisis management from evacuations, exclusion zones, and when it is safe to return. Eruption forecasting should not be viewed as an academic exercise or a theoretical discussion in a back room, nor is now the time for dramatic data interpretations or a set

Changbaishan-Tianchi volcano is a potentially hazardous intraplate volcano, and has gained increasing concern because of its volcanic unrest between 2002 and 2006. However, the magma system beneath this volcano is not well understood yet. Electrical resistivity is highly sensitive to the presence of interconnected partial melt and/or saline fluid. A total of 41 magnetotelluric (MT) sites were occupied

Magma movements are almost universally associated with volcanic deformation. The Mogi (1958) and McTigue (1987) models link observed surface displacements to behaviour within inaccessible magmatic plumbing systems. Mogi and McTigue models are well-used due to their computational simplicity and ease of application, but both models are limited by their assumptions about the deformation source and its

Previous calculations of total diffuse carbon dioxide (CO2) emissions from Yellowstone National Park have been based on flux measurements from thermally active, altered basins. However, our recent measurements show that thermally inactive, cold degassing sites can emit more diffuse CO2 per km2 than thermally active basins. The contribution of these cold degassing sites must be included in calculations

The Lusi mud eruption in East Java has been active since May 2006. Magma emplacement at depth, clay dehydration, and mud liquefaction during seismic wave propagation have been invoked as mechanisms fueling this eruption. However, the respective roles of these processes are still poorly constrained. In this focused study, we numerically investigate the influence of clay dehydration, mass and heat transport

The utility of infrasound technology for detecting explosive eruptions is well established. However, many active volcanoes are currently monitored exclusively with seismic networks and lack infrasonic sensor networks. Here, we demonstrate the ability of template matching to automatically detect ground-coupled airwave signatures (infrasound signals recorded on seismometers), associated with mild to

The Sośnica Hill volcano is part of the Oligocene to Miocene (30.9–20.0 Ma) Strzelin volcanic field. . It is located 100 km east of the Ohře Rift in the eastern part of the Fore-Sudetic Block, south of the town of Strzelin, Poland. Modern quarrying has exposed the sub-volcanic magma feeder system of the central part of the volcano and an extrusive volcanic succession that includes a 40 m thick sequence

Deception Island (South Shetland Islands, Antarctica) is an active volcano characterized by a moderate level of seismic activity, dominated by long-period seismicity related to hydrothermal processes in a shallow aquifer. Nevertheless, in the last few decades the volcano has undergone at least three episodes of seismic unrest, in 1992, 1999, and 2015. During these episodes, the pattern of seismicity

A field-based study used geologic mapping and a ground-based magnetic survey to investigate the exhumed central intrusive complex (CIC) of Summer Coon stratovolcano in Colorado. The CIC comprises a group of diorite to granodiorite stocks and sub-vertical domains of conduit-filling breccia hosted within basaltic-andesite breccia associated with cone building. The stocks serve as the focal points for

We present an ambient noise tomographic study of the mid-crustal magmatic system in the Katmai area, Alaska. Using multi-component (vertical and radial) seismic records at 70 stations deployed at various times over 20 years, we construct corresponding cross-correlograms and extract ~1010 Rayleigh-wave dispersion curves in the periods between 2 and 30 s. These enable us to obtain corresponding group

This paper presents results from a magnetotelluric survey at Ceboruco Volcano in Mexico. The observed data require an anisotropic 3-D electrical resistivity model which links a near-surface geothermal reservoir to the magmatic system and finally to the local tectonic setting. Ceboruco is an active stratovolcano, which is located in the Tepic-Zacoalco Rift and is part of the Trans-Mexican Volcanic Belt

Transcrustal magma transport systems reflect accumulation of small-volume intrusions over long timescales, transiently altering the thermal, mechanical, and compositional states of the crust. The long-term impact of such repeated and spatially-distributed intrusive magmatism on surface topography remains relatively unexplored. Here, we investigate the development of topography associated with multiple

The correlation between onshore and offshore of the volcanic features in a complex volcanic field area is a difficult task, however, it is a fundamental step in order to better understand the geological evolution of such a complex area and for an assessment of geologic hazards. Ischia is a well exposed and densely populated volcanic field located in the Campania volcanic province of Italy. In order

Due to its geodynamic location in the Lesser Antilles arc, Basse-Terre of Guadeloupe displays an active volcanism which is favourable to the development of high-enthalpy geothermal energy. An exhumed analogue of the Bouillante geothermal reservoir has been recently characterized in Terre-de-Haut island (Les Saintes archipelago), giving an opportunity to study the cooling of a natural geothermal system

Low-aspect-ratio ignimbrites, produced by the most lethal volcanic eruptions, are thin but laterally extensive and can serve as good stratigraphic markers in many sedimentary basins. They are commonly structureless, and require diverse analytical tools to reveal the related geological processes. This study aims to understand better the eruptive and depositional processes of the Cretaceous Kusandong

Despite decadal–millennial repose periods, volcanoes of the Canary Islands pose significant, though poorly understood hazards to local communities and infrastructure. At least 13 volcanic eruptions forming monogenetic cones and lava flows have occurred in the archipelago since 1500 CE: six on the island of La Palma (in 1585, 1646, 1677–1678, 1712, 1949 and 1971), four on Tenerife (1704–1705, 1706,

Raikoke, a small, unmonitored volcano in the Kuril Islands, erupted in June 2019. We integrate data from satellites (including Sentinel-2, TROPOMI, MODIS, Himawari-8), the International Monitoring System (IMS) infrasound network, and global lightning detection network (GLD360) with information from local authorities and social media to retrospectively characterize the eruptive sequence and improve

Camp dels Ninots is a mixed hard-soft maar-diatreme located in the Catalan Volcanic Zone (NE of Iberia), in which intra-maar lake sediments have preserved one of the most remarkable Pliocene fossil records in Europe. Geophysical surveys combined with the geological map and 11 boreholes, including two new continuous intra-crater drill cores, have enabled the construction of a 3D geological model of

Hydrovolcanic rootless cones form through the explosive interaction between lava and external water at locations remote from primary vents. Littoral rootless cones such as those on the coast of Hawaiʻi form at the ocean entries of basaltic lava flows and most consist dominantly of thinly bedded ash and lapilli. In contrast, the littoral rootless cones at ʻAuʻau Point and South Puʻu Kī Cone on the southwestern

The Malinche Pumice II is a fallout deposit produced by a Plinian-type eruption during the Pleistocene-Holocene at La Malinche volcano. La Malinche (4461 masl) is an active stratocone located in central Mexico, in the Trans-Mexican Volcanic Belt province. It is 26 km to the NE of the City of Puebla and 22 km to the SE of the City of Tlaxcala. The Malinche Pumice II was produced by one of the largest

A questionnaire to survey the common petrological monitoring procedures adopted by volcano monitoring institutions has been developed, aimed at identifying prevailing techniques and rating their suitability in terms of costs versus benefits. The collected information resulted from a sample of eighteen participating institutions, which include countries with some of the most important active volcanic

Magma plumbing system in active volcano can transport and store magmas, which is a key element for hazard assessment. The Quaternary volcano cluster of northern Hainan Island, an active volcano area in China, has been associated to a mantle plume. However, certain details such as the pathway of the ascent of magma and its storage in the crust remain unclear. In this work, a 68 km long magnetotelluric

The Auckland intraplate volcanic province consists of four small fields of basaltic monogenetic volcanoes. Each of these was active for a period of ~1 Myr and during the last 3 Myr the locus of magmatic activity migrated northward in discrete ~50 km steps. The most recent of these volcano fields is the Auckland Volcanic Field (AVF) in which individual eruptions have produced discrete magma batches

The tensile strength of volcanic rock exerts control over several key volcanic processes, including fragmentation and magma chamber rupture. Despite its importance, there is a paucity of laboratory data for the tensile strength of volcanic rocks, leading to an incomplete understanding of the influence of microstructural parameters, such as pore size and shape (factors that vary widely for volcanic

The evolution of volcanic activity observed at the New South East Crater (NSEC) and Voragine (VOR) between July 2019 and January 2020 has been deciphered by taking into account the changes of textures and chemical zoning of plagioclase and olivine crystals from the erupted lavas and tephra. The petrological observations have been integrated with analyses of the amplitude and source location of volcanic

Significant variations in temperature, water chemistry and volume of the lake in the crater of Maly Semyachik volcano, Kamchatka, in 1965–2020 can be divided in three main stages. The first stage, until about the mid-1980s, was characterized by intense volcanic-hydrothermal activity, high (above 40 °C) temperature, high salinity (up to 40 g/l) and an increase in the level (and volume) of the lake.

The Southern Andes margin hosts active and fossil volcanic, geothermal, and mineralized systems documenting intense geofluid migration through the crust. Fluid flow is also spatially associated with crustal faults that accommodate the bulk deformation arising from oblique plate convergence. Although recognized, the precise local mechanical interaction between faults and crustal reservoirs is yet to

Detailed processing and analyses of aeromagnetic data supported by geological constraints shed new light on the structural framework and plumbing system of Huichapan Caldera and Nopala volcano in the northern sector of the Mexican Volcanic Belt. The interpretation of magnetic anomalies is complex due to the bipolar nature of the magnetic field so we applied reduction to the pole using a double fast

The volcano-seismic crisis afflicting Mayotte since May 2018 has motivated France-based seismologists to consider the installment of a permanent seafloor observatory with one or more seismometers for monitoring surfacing magma and the associated seismicity. In general, deploying a seismometer offshore is known to improve earthquake location – particular in depth – and lower magnitude detection. However

Here we discussed the results of the first geochemical investigation of the fluids (groundwater and the associated gases) emerging in the southwest of Yazd Province. We carried out two surveys, one in July 2019 and the second in September 2019s, in the region of the Gariz aquifer (central Iran). We focused our attention to 1) the chemistry of the water (major and minor constituents coupled to the stable

Understanding past eruption dynamics at a volcano is crucial for forecasting the range of possible future eruptions and their associated hazards and risk. In this work we use numerical models to recreate the footprints of pyroclastic density currents (PDCs) and tephra fall from three eruptions at Gede volcano, Indonesia, with the aim of gaining further insight into these past eruptions and identifying

Long Period (LP) seismicity is considered a key indicator of fluid migration in the volcanic edifice, with a source mechanism typically ascribed to fluid resonance in the volcano conduit and fractures. Our viscoelastic numerical wave propagation models at laboratory and field scales are based on quantitative estimates of wave speeds and intrinsic attenuation from Whakaari rocks saturated with a range

Ceboruco volcano in western Mexico is catalogued as one of the five most hazardous volcanoes in the country (National Center for Disaster Prevention; CENAPRED); 32,927 people, distributed in several smaller cities, towns and villages, live within a 10 km radius from the volcano. Two permanent Global Navigation Satellite system (GNSS) stations were installed on the Ceboruco volcano in October 2018 to

Ceboruco Volcano is a Quaternary stratovolcano located in Nayarit near the Trans-Mexican Volcanic Belt western limit. It is one of the most active in the region and the only volcano in Nayarit with historically documented eruptions, the last one between 1870 and 1875. Currently, seismicity and fumarolic activity suggest hydrothermal activity. To study the geoelectrical setting at Ceboruco Volcano and

The active cone of Mt. Slamet is situated above the Guci Valley, making it vulnerable to volcanic eruptions. This is a fast-growing resort area with a permanent population of thousands and annual visitation in the hundreds of thousands. In this study, we combined stratigraphic observations with petrologic and geochemical analysis of volcanic rocks deposited in the valley to better understand the potential

The parallel Halmahera and Sangihe arcs in eastern Indonesia are sites of active arc-arc collision of considerable interest in developing understanding of the geodynamics and geochemistry of subduction zones. Owing to the comparative remoteness of the region, few ground-based studies of the volcanoes have been undertaken. Here, we report and integrate gas measurements and (isotope) geochemical analyses

The small volcanic islands of the central Greater Kuril Chain (GKC) produce strong explosive eruptions, two of which occurred in the recent years. The latest eruption took place at Raikoke volcano, which occurred on June 21–25 (2019) and was one of the largest on the Kuril Islands in the 21st century. This study presents mineralogical, petrographic and geochemical data on the air fall ash and pyroclastic

Diffuse emission of magmatic CO2 is one of the main indicators of volcanic unrest at Mammoth Mountain, but the presence of deep seasonal snowpack at the site has hindered year-round CO2 flux observations. A permanent eddy covariance station was established at the largest area of diffuse CO2 degassing on Mammoth Mountain (Horseshoe Lake tree kill) that measured CO2 fluxes (Fc) and meteorological parameters

We report methane (CH4) with variable carbon isotopes (between −60.9‰ and − 26.8‰) from Changbaishan, the most dangerous volcano in NE China. Furthermore, recent chemical and isotopic data of He, CO2, and CH4 in hot spring gases at Changbaishan volcano are also presented. Bubbling gas samples were collected periodically from 2014 to 2019 in three hot spring areas in the Changbaishan volcanic field:

Geothermal systems developed in volcanic regions release magmatic volatiles that may forecast volcanic eruptions. These volatiles can be emitted directly in gaseous form to the atmosphere or can be absorbed by condensed geothermal fluid and groundwater that discharges at surface thermal features. The subsurface flow dynamics of these fluids are therefore crucial for the interpretation of their chemical

Nishinoshima, a volcanic island in the Ogasawara (Bonin) island arc, has intermittently erupted since November 2013 after a quiescence of nearly 40 years. The three-dimensional (3D) magnetization structure of this growing volcanic island was investigated for the first time by acquiring aeromagnetic data with an unmanned aerial vehicle (UAV) system and subjecting the data to a 3D regularized inversion

Volcanic lightning generates high temperatures (>1500 °C) that melt volcanic ash particles, which re-solidify into lightning-induced volcanic spherules (LIVS). These LIVS have been documented within several ashfall deposits from multiple explosive volcanic eruptions. While several studies have analyzed the morphology and formation processes of LIVS, there is limited research on the chemical composition

Several global databases of eruption properties have been developed in recent years, which contain eruption age, eruption magnitude, eruption style, and volcanic explosivity index. However, their examinations of the relationship between eruption and magmatic properties remain qualitative. To explore such relationships, we sampled and petrologically analyzed the eruptive products and have constructed

This discussion concerns the flowage of the 1991 lava lobes at Unzen that were suggested by Goto et al. (2020) to be moving rigidly. Pictorial evidence of flowage of the 1991 lava lobe of Unzen, such as morphological change of the lava lobe, protrusion of the front of lava lobe, crease structure, and wrinkle surface of lava blocks, are presented. Differences in the interpretation of flow mechanisms

The Quaternary Coso volcanic field (CVF) is a compositionally bimodal volcanic field located within a releasing bend along the eastern range-front Sierra Nevada fault zone in California's southern Owens Valley. The erupted products of CVF silicic magmatism since ~1 Ma comprise 38 high-silica rhyolite domes, with the volumetric majority (~99%) of rhyolite emplaced within the past ~300 ka. The CVF hosts

The Hofsjökull volcanic system is located at the northern border of the Hreppar microplate on the Mid-Atlantic plate boundary in Iceland, between the more active Western and Eastern volcanic zones. In this study, fractures, and faults within the fissure swarms of the volcanic system were mapped and the throw and orientation of faults measured. This was done using both aerial photographs and ArcticDEM