Geophysical and geochemical networks are routinely deployed on active volcanoes to observe and monitor unrest periods. However, changes of the physical parameters with time are related to either magma/fluid movement or variations occurring in the hydrothermal systems hosted in the volcanic edifice. Here we use four years of ambient seismic noise recorded at the Stromboli volcano to reconstruct its

Explosive, caldera-forming eruptions are exceptional and hazardous volcanic phenomena. The 1883 eruption of Krakatau is the largest such event for which there are detailed contemporary written accounts, allowing information on the eruptive progression to be integrated with the stratigraphy and geochemistry of its products. Freshly exposed sequences of the 1883 eruptive deposits of Krakatau, stripped

Isotopic (D, 3H, 18O, and 34S) and chemical studies on the hyper-acidic hot spring waters (Obuki; pH 1.1), other hot spring waters, and fumarolic gases taken in 1990–1992 at Tamagawa Hot Spring, Akita, Japan were undertaken to investigate the source and behavior of sulfur compounds. The Obuki hot spring water discharges after mixing of magmatic gas with meteoric water and underground vapor–liquid separation

Motuoapa Peninsula, located in the southeast of the Taupo Volcanic Centre, New Zealand, is dominated by a silicic pyroclastic cone and overlaying lavas. The pyroclastic succession has not been recognised and studied before, and its thickness and sedimentological characteristics indicate completely different eruption mechanisms than proposed for the other pyroclastic successions within the central Taupo

A detailed lithofacies analysis in Continental Flood Basalt Provinces allows the comprehension of their evolution and paleoenvironmental significance. In the northern portion of the Paraná-Etendeka Igneous Province (PEIP), in Brazil (Uberlândia-Araguari area), a volcanological and stratigraphic approach provided evidence that the basaltic volcanic succession is not monotonous, involving different lava

Geodetic modelling has become an established procedure to interpret the dynamics of active volcanic plumbing systems and magma transfer within the crust. Most established geodetic models implemented for inverting geodetic data share similar physical assumptions: (1) the Earth's crust is modelled as an infinite, homogeneous elastic half-space with a flat surface, (2) there is no anisotropic horizontal

Basaltic tuyas are glaciovolcanoes that form when substantial focused eruptions take place beneath thick ice. None have been witnessed, so models reconstructing tuya formation are grounded in detailed fieldwork. A key feature of many basaltic tuyas is the presence of volcanic and volcaniclastic rocks that indicate the sustained presence of an encircling meltwater lake during the eruption. Here we provide

Sangay is one of the most active volcanoes in the world. Its eruptions were first recorded by Spanish priests in 1628, and since 2010 it has displayed VEI 1–2 level eruptive activity about every two years. Its most recent eruptive phase began on May 7, 2019, and has continued until the present. While most eruptive products do not impact inhabited areas, Sangay's associated Pleistocene-age avalanche

The spaceborne detection of volcanic ash clouds at infrared wavelengths helps to avoid regions with enhanced volcanic ash concentrations that pose a threat to aviation. Current volcanic ash data retrievals require detailed information on microphysical properties and the refractive index of volcanic ash, which are highly variable. Uncertainties in the latter currently limit the quality of volcanic ash

Three fissure eruptions are known to have occurred along the northeastern edge of Kīlauea's summit caldera in the 19th century—in the years 1832, 1868, and 1877. Modern portrayal of these eruptions on maps and in written sources indicates that the 1832 eruption was from a fissure on the side of the Poliokeawe scarp south of Byron Ledge, the 1868 eruption was from a fissure on the southern wall of Kīlauea

Volcanic ash and pyroclasts can weld when deposited hot by pyroclastic density currents, in near-vent fall deposits, or in fractures in volcano interiors. Welding progressively decreases the permeability of the particle packs, influencing a range of magmatic and volcanic processes, including magma outgassing, which is an important control on eruption dynamics. Consequently, there is a need for a quantitative

Volcaniclastic stratigraphy can be difficult to map and describe due to its complex nature. However, such stratigraphy preserves information about fluctuations in volcanic activity and sedimentation and is vital to understanding volcanic systems. Uncrewed aerial vehicle (UAV) based analysis of volcanic stratigraphy can enhance mapping and analysis, especially on vertical surfaces where outcrop exposure

The research for developing an automatic recognition system of volcanic microearthquakes have been an important task around the world, based on this, the aim of this paper is to present an automatic recognition system of microearthquakes from the Cotopaxi Volcano based on a deep learning approach. The detection and classification stages were carried out with Convolutional Neural Networks by using spectrograms

Decades of space exploration reveal that Mars has been reshaped by volcanism throughout its history. The range of observed volcanic landforms shows that effusive and explosive eruptions have occurred, albeit unevenly in time and space. Evidence for explosive volcanism—characterized as eruptions in which magma is disrupted by the expansion of dissolved gases or by an interaction of magma with external

Given the high eruption recurrence in the Michoacán-Guanajuato volcanic field (MGVF) in central Mexico, the birth of a new monogenetic volcano can be expected in the future. It is important, therefore, to reconstruct the past eruptions of its many different volcanoes, including estimates of lava flow emplacement times and their rheological properties. These studies define the range of possible future

Models of volcanic eruption periodicity are vital for hazard prediction, but require an understanding of the past pattern of melt evolution and transport. Zircon double-dating combines (U-Th)/He methods with U-Pb and U-Th disequilibrium geochronology to determine the timing of volcanic eruptions for rocks with a particular emphasis on those younger than ca. 1 Ma. This paper focuses on the Jeju Island

The Kamo Volcanic Field (KVF), a partly preserved Quaternary volcanic sequence of three small-volume basaltic volcanoes located about 10 km northwest of the Aira caldera in the Kagoshima graben in southwestern Kyushu, Japan. It forms part of the volcanic arc of Japan and consists of the Late Pleistocene Aojiki volcano and two Holocene maars: Sumiyoshiike and Yonemaru. Here, we report the first results

Large-magnitude volcanic eruptions are rare; for this reason, those that have occurred in recent history provide important case studies of syn- and post-eruptive impacts. One under-studied example is the 1902 Plinian eruption of Santa María volcano, Guatemala. Sources from the time tell us that volcanic ash from the eruption travelled thousands of kilometres, and that associated hazards may have caused

Long-term instrumental monitoring of open-vent volcanoes provides the necessary datasets to characterize volcanic activity and unravel its temporal changes. This is particularly important for active lava domes, which can undergo rapid transitions in behavior over the course of their eruption. Here, we analyzed seismic, acoustic infrasound and thermographic data collected between January 2018 and September

Round Butte (Hopi Buttes volcanic field, Arizona) exposes a diatreme 170–190 m across, 190 m below the pre-eruptive surface. The central part of the massif is 130–150 m in diameter, displaying 20–30 m-high subvertical cliffs. The well-known layer-cake stratigraphy of the sedimentary rocks of the Colorado Plateau permits identification of the largest lithic fragments preserved in the Round Butte diatreme

The classification of seismo-volcanic signals is performed manually at La Soufrière Volcano, which is time consuming and can be biased by subjectivity of the operator. We propose here a machine-learning-based model for classification of these signals, to handle large datasets and provide objective and reproducible results. To describe the properties of the signals, we used 104 statistical, entropy

Edifice collapse represents one of the most dangerous volcanic hazards threatening communities and infrastructure near volcanoes, having caused over 20,000 casualties in the past 400 years. Despite its prevalence across volcanic settings, flank instability has mostly been considered at ocean island volcanoes. In Guatemala, all but one volcano with elevation greater than 2000 m have undergone edifice

Silica-rich coatings of up to 660 μm thickness were found on the juvenile volcanic lapilli and blocks of the 1783 CE pyroclastic flow deposits 1.9–3.6 km northeast of the Maekake crater of Asama volcano in Central Japan. These coatings are composed of fine-grained volcanic ash particles with silica-rich cement. Raman spectroscopic measurements revealed that the interstitial silica-rich phase is hydrous

Volcanic activity is widespread within the inner Solar system and it can be commonly observed on rocky planets. In this work, we analyse the structures of Pavonis Mons in the Tharsis volcanic province of Mars by performing structural mapping, azimuth, and topographic distribution of linear features on the flanks of Pavonis, such as grabens and pit chains. We tested whether their formation is to be

The behaviour of dry and wet volcanic granular flows is one of the main research topics in present day geophysics and volcanology. It involves various disciplines (e.g. sedimentology, geophysics, fluid dynamics) and investigation techniques (e.g. field studies, laboratory experiments, computational fluid dynamics). The vast interest is justified by the complex nature of these flows and their very dangerous

Pre-eruptive volatile contents recorded by melt inclusions from ocean island settings such as Hawaii constrain the extent of deep Earth outgassing on geologic timescales by mantle plume activity. However, melt inclusions trapped from a partially degassed magma will not reflect the original volatile content of the primary melt, and relatively silicic (>45 wt% SiO2) shield-stage tholeiites are more likely

The recent and growing development and availability of unmanned aerial vehicles/systems (UAV, UAS, or “drones”) in volcanology has promoted a significant advance in volcanic surveillance of active volcanoes and in the characterization of volcanic landforms and hazards. However, in the tropics with heavy rainfall, deep volcanic soils and high relief, UAV surveying for volcanic geomorphology and volcanic

Cuicocha Caldera is the youngest eruptive center of Cotacachi-Cuicocha Volcanic Complex, located at the north of Ecuador. The caldera contains a lake of 3.95 km2 surface, and a maximum depth of 148 m. Cuicocha Lake is characterized by the presence of CO2 gaseous diffuse emissions, perceptible as bubbling zones. Since 2011, CO2 diffuse flux measurements have been performed in this lake using the accumulation

Active lava surfaces emplaced during effusive eruptions are typically observed in the form of lava flows, lakes, or domes. There are numerous volcanoes on Earth that regularly produce active lava including Kīlauea volcano in Hawai'i, which had a continually-active lava flow field from the 1980s until the end of the last eruptive phase in 2018. During the last decade of that period, it also had a persistent

Lava that erupted during the 2014–2015 Holuhraun eruption in Iceland flowed into a proglacial river system, resulting in aqueous cooling of the lava and an ephemeral hydrothermal system. We carried out a monitoring study of this system from 2015 to 2018 to document the cooling of the lava over this time, using thermocouple measurements and data-logging sensors. The heat loss rate from advection through

Avachinsky, Kozelsky, and Koryaksky volcanoes form one of the most volcanically active clusters in the Kamchatka volcanic arc and are located in close proximity of the cities of Petropavlovsk-Kamchatsky and Elizovo – the most populated area in Kamchatka. In this paper, we report a compilation of new and revised previously published data on the eruptive history of these volcanoes during the past 13

We present the monitoring of a submarine volcanic eruption that took place near the southernmost emerged land of El Hierro Island (Canary Islands, Spain), from October 2011 to February 2012. Right after the onset of the eruption, in mid-October 2011, we deployed an offshore geophone array for the purpose of monitoring the submarine eruptive activity signals. It acquired continuous data from October

The goal of this study is to explore “ideal” analytic functional forms that best fit the topographic shape of N = 190 isolated stratovolcanoes from around the world. Using a stochastic model for the piling of lava flows to demonstrate one set of physical processes that give rise to a stratovolcano's topography, we find that although the ideal form fits well for many stratovolcanoes, there exist deviations

In central Mexico, remnants of the early volcanic activity in the Trans-Mexican Volcanic Belt (TMVB) are exposed at Sierra de Guadalupe in the northern part of the Mexico City Basin and to the south in the Tepoztlán, Malinalco, Tenancingo, and Chiltepec areas. A few published studies indicate a general early to middle Miocene age for some of these volcanic centers. We present new geologic, geochronologic

Samples of efflorescences and encrustations of hydrothermal origin were collected at Sousaki (Greece) and analysed for their mineralogical (XRD) and chemical composition. Solutions obtained both from mineralization with HNO3 and from leaching with deionised water were analysed for major (ICP-OES), minor and trace metals (ICP-MS) and sulfate contents (IC). Results evidence the dependence of the chemical

Blue Lake crater (<3 ka) is monogenetic volcano that produced one of the youngest eruptions in the central Oregon Cascades. Understanding monogenetic volcano behavior – from storage through eruption – is imperative in planning for future eruptions. Here we combine physical volcanology and geochemistry to determine the pre-eruptive storage conditions, ascent rate, eruption style, and deposit distribution

Vesicle textures in submarine lavas have been used to calculate total (pre-eruption) volatile concentrations in mid-ocean ridge basalts (MORB), which provide constraints on upper mantle volatile concentrations and global mid-ocean ridge CO2 flux. In this study, we evaluate vesicle size distributions (VSDs) and volatile concentrations in a suite of 20 MORB samples that span the range of vesicularities

Shiveluch is one of the most active explosive volcanoes worldwide. During the last рlinian eruption in 1964 and the following (1980-current time) dome-forming eruptions Shiveluch has produced andesites and dacites (SiO2 ~ 60–64 wt%) containing variably zoned, compositionally and texturally diverse amphibole phenocrysts. In this work, we attempt to decode the complex zoning of the amphibole crystals

The ground response to the production of energy in geothermal fields can be observed in the form of ground displacement and seismic activity. Changes in the temperature, volume, pressure of the reservoir can culminate in surface deformation and in seismicity at the reservoir edges and/or near the production wells. Identifying the origin of the ground response enables controlled management of the reservoir

Seismic based geophysical methods are seeing increased usage in evaluating geothermal resources in order to maximize resource potential. However, interpreting geophysical data (such as velocities and dynamic modulus and fracture density/alignment) generated from geothermal reservoirs remains difficult. Here we present the results of a new laboratory study measuring seismic attributes of fresh and hydrothermally

The Danakil depression marks a progressive change from continental rifting in Afar to seafloor spreading further north in the Red Sea. Extension and volcanism in this incipient spreading centre is localised to the ~70-km-long, 20-km-wide active Erta Ale volcanic segment. Here, we combine remote sensing and major element geochemical analysis to determine the structure and composition of three volcanoes

Barren Island, situated in the Andaman Sea, is the northernmost active volcano of the Sunda arc. The oldest known eruption of the volcano was during the period 1787–1832. After about 150 years of quiescence, volcanic activity resumed in 1991 and continues since then. The magmatic plumbing system of this volcano is largely unknown due to lack of geophysical experiments owing to its remote location.

The Quetrupillán Volcanic Complex is a composite system, active since the Pleistocene. We combine petrological and geochemical data from its erupted products with structural and geometrical constraints applied to the overall system and region. We conclude that a basaltic source melt is hindered on its ascent through the crust due to a compressional tectonic regime, influenced further by the structural

Volcanic gas compositions are estimated based on volcanic plume measurement with Multi-GAS at a frequently erupting Sakurajima volcano by application of airborne methods and automatic monitoring station on the flank during 2013–2019. The airborne measurements of CO2 and H2O concentrations often suffer from large fluctuation of background likely due to entrainment of the atmosphere derived from different

The morphologies of craters on planetary surfaces reveal clues about the geologic mechanisms by which they originate and subsequently evolve, as well as about the materials and physical variables inherent to the environment in which they formed. We carried out a quantitative multivariate analysis of shape descriptors derived from the outlines of craters formed by volcanic processes on Mars, Io, and

The Miocene Aertashi Debris-Avalanche Deposits at the southwestern Tarim Basin, the foreland basin of the Eastern Pamir (NW Tibetan Plateau), have an incredibly long-runout distance (much longer than 130 km) and provide critical constraints on the evolution of drainage patterns, tectonics, and geochronological framework of the region. To investigate when and how the deposits formed, we conducted extensive

Major, minor and rare earth elements were analyzed in the acid sulphate - chloride thermal springs associated to Puracé volcano – hydrothermal system. The waters of Puracé were classified in 2 different groups as a function of the physico-chemical parameters and element distributions. Group 1 is characterized by the highest pH (⁓ 3.5), an outlet temperature of ⁓ 81 °C and a strong depletion of Fe,

Understanding the links between the magma differentiation processes, the magma plumbing system and the magma composition at arc volcanoes is of paramount importance for volcanic hazard assessment. In this work we focus on the post-glacial, Holocene, historical, and recent eruption products of Ubinas volcano (Peru), which display an overall decrease in silica content from the older, plinian (VEI 3–5)

Popocatepetl volcano located in central Mexico has been erupting since December 1994 and since then many studies have been carried out in order to understand its eruptive behavior and assess the volcanic hazard since more than 25 million people are at risk. Nevertheless, few geophysical studies have been conducted in order to image the structure of the volcano. For this reason, we carried out magnetotelluric

Surface temperature at a volcanic system is the result of a mixture of two heat sources originating one from above and another from below the ground surface. The atmosphere significantly affects the surface's temperature of the volcano, and removal of the atmospheric effect is required for meaningful interpretations prior to any characterization of anomalous volcanic activity. Time series of meteorological

The first gas and thermal measurements at the summit of the Gamalama volcano indicate that the system is dominated by hydrothermal processes. This is highlighted by the prevalence of H2S over SO2 (H2S/SO2 = 2–8), a high CO2/SO2 ratio (76–201), and a low heat transfer (3.0 MW) to the surface. A relative variation in gas composition is observed along the degassing fracture zone, possibly due to partial

Adequate detection and classification of seismic events are crucial for understanding the internal status of a Volcano. Machine learning-based classifiers use different features from the time, frequency, and scale domains related to seismic events. Regarding power spectrum-based features, several methods can be used to compute such features. However, the more suitable method for analyzing volcanic

The genesis, distribution and hazards associated with monogenetic volcanic fields pose particular difficulties derived from their dispersed character. Establishing a relationship between the spatial and the age distributions of volcanic cones is necessary both to understand the nature of monogenetic field formation and evolution and to set supported hazard-assessment criteria. We present here a new

Despite their generally low volume fraction, FeTi oxides have the potential to greatly influence the eruptive style because they lower the supersaturation pressure for heterogeneous bubble nucleation. Once nucleated, bubbles respond fast to pressure changes, fostering rapid expansion and explosive behavior. Yet, oxide microlite quantifications are often absent from data of explosive products. We used

We established the phase equilibria of a representative tephriphonolitic sample of the 1631 eruption of Vesuvius (Italy). Experiments were conducted at 100 MPa, in the temperature range 950–1050 °C for melt water content ranging from 1.3 to 3.2 wt%, and at an oxygen fugacity (fO2) of NNO+1 to NNO+3 (one to three log unit above the fO2 of the Ni-NiO solid redox buffer). Results show that clinopyroxene

The 1783–1784 Laki eruption was one of the most severe natural catastrophes to occur in Iceland since settlement (around 870 CE). Vegetation damage by sulphate aerosol and fluorine poisoning caused a massive decimation of livestock which brought famine and excess deaths of 1.6 of the population. 18th Century Iceland was a Danish dependency and, despite the abundance of fish in the surrounding waters

Hydrothermal systems with active surface expressions are important natural source of atmospheric mercury. Here we report on the first simultaneous assessment of gaseous elemental mercury (GEM) and major volatiles (H2S and CO2) fluxes from the fumarolic system of Pisciarelli, currently the most active at the Campi Flegrei caldera (CFc), Naples (Italy). This was achieved via a GPS-synchronized Lumex

Since 1994 Popocatépetl volcano has extruded 85 lava domes, each of which has been destroyed by Vulcanian-style explosions. The paroxysmal Vulcanian explosion of 22 January 2001 has been unique by generating multiple pyroclastic density currents (PDCs). Scientists and Civil Protection authorities have used those PDCs to remap the high-risk hazard zone of the volcano, although little study has been