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Süd-Zentralchile ist eine geodynamisch aktive Region, die von starken Erdbeben, Massenbewegungsprozessen und häufigen Vulkanausbrüchen geprägt wird. Die Landschaft zeigt den signifikanten glazialen Einfluss auf die Geomorphologie durch Vergletscherungen des späten Quartärs. Diese glazialen, vulkanischen und tektonischen Prozesse verursachen Landschaftsveränderungen, die langfristige geomorphologische und sedimentäre Spuren hinterlassen. Der Lago Llanquihue (41,156°S; 72,816°W) ist ein großer und tiefer (40x40km; 317m tief) Vorlandsee am westlichen Fuß der Anden und stellt einen wichtigen touristischen Hotspot dar. Sein aktueller Abfluss befindet sich im Westen, und sein kleines Einzugsgebiet wird von zwei aktiven Vulkanen dominiert: Osorno und Calbuco. Basierend auf früheren geomorphologischen Studien aus den 1960er und 70er Jahren wurde die Hypothese aufgestellt, dass der Seespiegel des Lago Llanquihue während dem Spätglazial wesentlich höher und während des Holozäns deutlich niedriger war. Er stieg erst im Spätholozän auf sein heutiges Niveau. Laut dieser Hypothese stauten Lahar- und/oder Lavaflüsse den früheren Abfluss im Osten, was zu einem Anstieg des Seespiegels und anschließendem Abfluss nach Westen führte. In dieser Studie soll diese Theorie überprüft und verfeinert werden, indem subaquatische, geomorphologische Merkmale und Sedimentationsmuster im Lago Llanquihue untersucht werden. Wir ergänzen diese Daten durch eine sedimentologische Studie von Laguna La Poza, einem kleinen See (1,7x0,2km; 6m tief) in einem Flusstal, das durch den Anstieg des Seespiegels im Spätholozän überflutet worden sein soll. Darüber hinaus bewerten wir Hinweise für spätglaziale Seespiegelhochstände durch sedimentologische Kartierungen rund um den See. Terrestrische Aufschlüsse und geomorphologische Analysen des digitalen Höhenmodells ergaben Paläoseeterrassen auf 72m ü. NN, 80-82m ü. NN und 87-94m ü. NN sowie Kame-Terrassensedimente im Nordwesten des Sees auf 105-144m ü. NN, die aus, South-Central Chile is a geodynamically active region that experiences significant subduction megathrust earthquakes, mass-wasting processes, and frequent volcanic eruptions. The landscape showcases the strong glacial influence on geomorphology from the glaciations of the Late Quaternary. These glacial, volcanic and tectonic processes induce landscape changes that leave long-lasting geomorphological and sedimentary traces. Lago Llanquihue (41.156°S; 72.816°W) is a large and deep (40 x 40km; 317m deep) piedmont lake at the western foot of the Andes, and forms an important touristic hotspot. Its current outflow is at the western edge, and its small catchment is dominated by two active volcanoes: Osorno and Calbuco. Based on previous geomorphological studies from the 1960s and 70s, it was hypothesized that the lake level of Lago Llanquihue was much higher during late glacial times and much lower during most of the Holocene. It rose to its present level only in the Late Holocene. According to this hypothesis, lahars and/or lava flows in the Late Holocene dammed the outflow in the eastern part of the lake system, leading to a lake level rise and subsequent drainage towards the west through the frontal moraine belts. In this study, we aim to test and refine this hypothesis by investigating the submerged geomorphological features and sedimentation patterns in Lago Llanquihue. We complement this data with a sedimentary study of Laguna La Poza, a small lake (1.7 x 0.2km; 6m deep) in a fluvial valley that is believed to have been inundated by the Late Holocene lake level rise. Moreover, we evaluate evidence for late glacial lake highstands through sedimentological field mapping around the lake. Terrestrial outcrops and geomorphological analysis of the digital elevation model revealed paleo-lake level terraces at 72m.a.s.l., 80-82m.a.s.l., and 87-94m.a.s.l., as well as kame terrace deposits in the northwest of the lake at 105-144m.a.s.l., originating from late glacial highstan, Masterarbeit Universität Innsbruck 2024

xplosive volcanic eruptions can inject high quantities of magmatic materials into the atmosphere representing a risk to life and society. To quantify the potential impacts of a future eruption or to forecast what will happen in the next few hours when a volcano is erupting, atmospheric dispersion models are commonly used providing important information for civil protection and other stakeholders. Spatiotemporal distributions of volcanic ash in volcanic plumes are used as an input by a numerical simulation of tephra dispersal and are called eruption source parameters (ESPs). They have been poorly constrained and therefore their variation between models affects volcanic tephra hazard assessment. Since the goodness of ESPs increases with knowledge of the dynamics of eruptive columns, reconstruction of volcanic columns from past eruptions will improve the assessment of volcanic hazards for future eruptions. In this work we take advantage of recent advances in computational capabilities and modeling in order to robustly reconstruct the dynamics of eruption columns from past eruptions. We do that by applying a synergistic approach between atmospheric dispersion models capable of reproducing the transport of volcanic ash due to atmospheric wind, eruption cloud dynamics models that resolve the ascending and the horizontal spreading of umbrella cloud, and inversion methods able to estimate ESPs using geological data information of tephra deposits. Specifically, we use the latest version of the ash dispersal model FALL3D that allows us to determine EPSs by inverting field data using the novel GNC (Gaussian with non-negative constants) ensemble-based inversion method, and the eruption cloud dynamics model SK-3D that accurately resolves the turbulence of the volcanic plumes. As an application, we focus on Campi Flegrei (CF) caldera, in Italy. CF is currently a densely populated area under busy air traffic routes where the monitoring system of the Vesuvius Observatory highlights

Short and long-term probabilistic volcano hazard assessments entail the fusion of data from multiple sources with the realisation and subsequent combination of hundreds/thousands of scenarios spanning the range of system uncertainties (model inputs and parameterisations, boundary conditions, etc). Computational workflows are middleware software layers that manage and orchestrate in an automated way the multiple steps and tasks involved in this process, from data acquisition and preparation, to model executions and post-process in centralised (HPC) and/or cloud computing infrastructures. This contribution presents some examples from on-going European projects tackling computational geohazards on HPC/cloud infrastructures. For the short-term hazard assessment, the DT-GEO project (2022-2025, Grant Agreement No 101058129) is implementing a number of workflows conducting precise data-informed early warning systems and hazard assessments by harnessing world-class computational (FENIX, EuroHPC) and data (EPOS) research infrastructures. The volcano-related workflows in DT-GEO include: (i) merging of multi-parametric data from ground-based and remote observation systems (on-site monitoring networks and satellites) with global modelling of magma and rock dynamics and with AI approach; (ii) merging of real-time geostationary satellite observations with the FALL3D model to generate deterministic and ensemble-based probabilistic forecast products; (iii) merging of real-time multi-parametric data from ground-based and remote observation systems with deterministic modelling of lava flow propagation and inundation areas and; (iv) air-quality data and AI in a volcanic gas dispersal forecast context to improve operational Early Warning Systems. On the other hand, the EuroHPC ChEESE Center of Excellence (CoE) is conducting an ensemble-based volcanic dispersal across multiple scales that will lead to the first European tephra hazard map at scale covering, simultaneously, long-range dis

Nowadays, volcanic eruptions pose a significant threat to society, particularly in monogenetic volcanic fields where prolonged recurrence periods lead to increased human settlements in their vicinity. This is mostly attributed to a false sense of security within the community potentially exposed to a future eruptive event. Such misconceptions often result in a lack of preparedness programs and resilience capabilities for potential future eruptions. In this context, the city of Olot (~34,400 inhabitants, Catalonia, Spain), located within the Garrotxa volcanic field, serves as an example of human settlement around monogenetic volcanoes, which the last known eruption occurred ~ 10.4 ¿ 15.7 ka ago. Although communities residing in this volcanic field demonstrate a sound understanding of their environment, there is a prevalent misconception regarding volcanic hazards, which often leads to perceive the area as inactive or even extinct. To evaluate the perception of volcanic risk among the population of Olot, we have conducted a survey segmented by age groups. The main objectives are: (i) identifying knowledge gaps and misconceptions within the population; (ii) analyzing the factors most relevant in determining risk perception within the community; (iii) contributing to the assessment of the population's resilience in the face of a future eruptive event: and (iv) ultimately evaluating the contrast between the perception of the Olot community and its actual volcanic risk.

On 15 January 2022, the Hunga volcano produced a massive explosion that generated perturbations in the entire atmosphere. Nonetheless, signatures in the mesosphere and lower thermosphere (MLT) have been challenging to identify. We report MLT horizontal wind perturbations using three multistatic specular meteor radars on the west side of South America (spanning more than 3,000 km). The most notorious signal is an exceptional solitary wave with a large vertical wavelength observed around 18 UT at all three sites, with an amplitude of ∼50 m/s mainly in the westward direction. Using a customized analysis, the wave is characterized as traveling at ∼200 m/s, with a period of ∼2 hr and a horizontal wavelength of ∼1,440 km in the longitudinal direction, away from the source. The perturbation is consistent with an L1 Lamb wave mode. The signal's timing coincides with the arrival time of the tsunami triggered by the eruption.

The Hunga Tonga–Hunga Ha'apai volcano eruption was a unique event that caused many atmospheric phenomena around the globe. In this study, we investigate the atmospheric gravity waves in the mesosphere/lower thermosphere (MLT) launched by the volcanic explosion in the Pacific, leveraging multistatic meteor radar observations from the Chilean Observation Network De Meteor Radars (CONDOR) and the Nordic Meteor Radar Cluster in Fennoscandia. MLT winds are computed using a recently developed 3DVAR+DIV algorithm. We found eastward- and westward-traveling gravity waves in the CONDOR zonal and meridional wind measurements, which arrived 12 and 48 h after the eruption, and we found one in the Nordic Meteor Radar Cluster that arrived 27.5 h after the volcanic detonation. We obtained observed phase speeds for the eastward great circle path at both locations of about 250ms^-1, and they were 170–150ms^-1 for the opposite propagation direction. The intrinsic phase speed was estimated to be 200–212ms^-1. Furthermore, we identified a potential lamb wave signature in the MLT winds using 5 min resolved 3DVAR+DIV retrievals.

Areas of old and cold oceanic plate lack conventional volcanism and have been assumed to be devoid of submarine hydrothermal activity. However, petit-spot volcanoes are common in areas of flexure of such oceanic plates. Here, we report hydrothermal ferromanganese oxides dredged from the vicinity of a petit-spot volcano at 5.7 km water depth in an area of oceanic plate flexure east of the Japan Trench. The bulk chemical, lead isotopic and mineralogical compositions of the samples indicate their formation by low-temperature hydrothermal activity, which can be interpreted as being caused by fluid–rock interactions at <200 °C. We propose that interaction of local marine sediments with volatile-rich petit-spot magmas may produce hydrothermal fluids containing not only iron and manganese but also enough amounts of carbon dioxide and methane to have implications for the global carbon cycle. However, contemporary hydrothermal activities at petit-spot volcanoes have not been confirmed yet.

Nanometer-sized crystals (nanolites) play an important role in controlling eruptions by affecting the viscosity of magmas and inducing bubble nucleation. We present detailed microscopic and nanoscopic petrographic analyses of nanolite-bearing and nanolite-free pumice from the 2021 eruption of Fukutoku-Oka-no-Ba, Japan. The nanolite mineral assemblage includes biotite, which is absent from the phenocryst mineral assemblage, and magnetite and clinopyroxene, which are observed as phenocrysts. The boundary between the nanolite-bearing brown glass and nanolite-free colorless glass is either sharp or gradational, and the sharp boundaries also appear sharp under the transmitted electron microscope. X-ray absorption fine structure (XAFS) analysis of the volcanic glass revealed that the nanolite-free colorless glass records an oxygen fugacity of QFM + 0.98 (log units), whereas the nanolite-bearing brown glass records a higher apparent oxygen fugacity (~ QFM + 2). Thermodynamic modelling using MELTS indicates that higher oxygen fugacities increase the liquidus temperature and thus induced the crystallization of magnetite nanolites. The hydrous nanolite mineral assemblage and glass oxygen fugacity estimates suggest that an oxidizing fluid supplied by a hot mafic magma induced nanolite crystallization in the magma reservoir, before the magma fragmentation. The oxidation-induced nanolite crystallization then enhanced heterogeneous bubble nucleation, resulting in convection in the magma reservoir and triggering the eruption.

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Biasi, J., Tivey, M., & Fluegel, B. Volcano monitoring with magnetic measurements: a simulation of eruptions at axial seamount, Kilauea, Baroarbunga, and Mount Saint Helens. Geophysical Research Letters, 49(17), (2022): e2022GL100006, https://doi.org/10.1029/2022GL100006., Monitoring of active volcanic systems is a challenging task due in part to the trade-offs between collection of high-quality data from multiple techniques and the high costs of acquiring such data. Here we show that magnetic data can be used to monitor volcanoes by producing similar data to gravimetric techniques at significantly lower cost. The premise of this technique is that magma and wall rock above the Curie temperature are magnetically “transparent,” but not stationary within the crust. Subsurface movements of magma can affect the crustal magnetic field measured at the surface. We construct highly simplified magnetic models of four volcanic systems: Mount Saint Helens (1980), Axial Seamount (2015–2020), Kīlauea (2018), and Bárðarbunga (2014). In all cases, observed or inferred changes to the magmatic system would have been detectable by modern magnetometers. Magnetic monitoring could become common practice at many volcanoes, particularly in developing nations with high volcanic risk., This work was supported by the NSF Grant No 2052963 to J. Biasi and an internal Woods Hole Oceanographic Institution grant to M. Tivey.

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Biasi, J., Asimow, P., Horton, F., & Boyes, X. Eruption rates, tempo, and stratigraphy of Paleocene flood basalts on Baffin Island, Canada. Geochemistry, Geophysics, Geosystems, 23(9), (2022): e2021GC010172, https://doi.org/10.1029/2021gc010172., High-temperature melting in mantle plumes produces voluminous eruptions that are often temporally coincident with mass extinctions. Paleocene Baffin Island lavas—products of early Iceland mantle plume activity—are exceptionally well characterized geochemically but have poorly constrained stratigraphy, geochronology, and eruptive tempos. To provide better geologic context, we measured seven stratigraphic sections of the volcanic deposits and collected paleomagnetic data from 38 sites in the lavas and underlying Cretaceous sediments (Quqaluit Fm.). The average paleomagnetic pole from this study does not overlap with the expected pole for a stable North American locality at 60 Ma, yet the data have sufficient dispersion to average out secular variation. After ruling out other possibilities, we find that the picrites were probably erupted during a polarity transition, over less than 5 kyr. If so, the average eruption interval was ∼67 years per flow for the thickest sequence of exposed lavas. We also calculate that the flood basalts had a minimum total volume of ∼176 km3 (excluding submerged lavas in Baffin Bay). This implies a minimum eruption rate of ∼0.035 km3 yr−1, which is similar to rates found in West Greenland lavas but less than rates found in larger flood basalts. Despite this, the Baffin and West Greenland lavas temporally correlate with the “End C27n event” (a period of ∼2°C global warming) and may be its underlying cause., his work was supported by the National Science Foundation (award #1911699 to F. Horton and award #2052963 to J. Biasi), Woods Hole Oceanographic Institution (WHOI) Andrew W. Mellon Foundation Endowed Fund for Innovative Research, a National Geographic Society grant (#CP4-144R-18), and internal funding from the Caltech Geological and Planetary Sciences Division.

New Zealand's largest city, Auckland, is situated within the basaltic Auckland Volcanic Field (AVF). Therefore, understanding the eruption history of the local volcanoes in the field is of great importance in order to assess future hazards that they may pose. Rangitoto is the youngest and largest volcano in the AVF, although the timing of the first eruption and the duration of the volcanic activity are still uncertain. Here, we use palaeomagnetic methods to provide additional constraints to the duration of the main shield-building phase of Rangitoto, previously estimated to have lasted either less than 100 years or approximately 1000 years. Lava flow samples from an -140 m length vertically oriented drill core produced 203 palaeoinclinations and 74 palaeointensity estimates. Our results show significant variation in both inclination (up to 30 degrees) and intensities (which fall between 25 and 60 & mu;T; present day field values for Auckland are -55 & mu;T). Potential non-geomagnetic explanations for these variations, including thermochemical processes and rheological deformation are discussed. A statistical model was created to determine the minimum duration for the construction of Rangitoto that is compatible with the variations in the palaeomagnetic data, using prior information about the rate of change of the geomagnetic field. We conclude that the palaeomagnetic data are incompatible with the previously suggested short duration (under 100 years) of the shield-building phase and suggest instead a range of 150-450 years, when also accounting for the available radiocarbon ages. Given these results, this has implications for the timing, and thus impact of possible future eruptions in the AVF.

New Zealand's largest city, Auckland, is situated within the basaltic Auckland Volcanic Field (AVF). Therefore, understanding the eruption history of the local volcanoes in the field is of great importance in order to assess future hazards that they may pose. Rangitoto is the youngest and largest volcano in the AVF, although the timing of the first eruption and the duration of the volcanic activity are still uncertain. Here, we use palaeomagnetic methods to provide additional constraints to the duration of the main shield-building phase of Rangitoto, previously estimated to have lasted either less than 100 years or approximately 1000 years. Lava flow samples from an -140 m length vertically oriented drill core produced 203 palaeoinclinations and 74 palaeointensity estimates. Our results show significant variation in both inclination (up to 30 degrees) and intensities (which fall between 25 and 60 & mu;T; present day field values for Auckland are -55 & mu;T). Potential non-geomagnetic explanations for these variations, including thermochemical processes and rheological deformation are discussed. A statistical model was created to determine the minimum duration for the construction of Rangitoto that is compatible with the variations in the palaeomagnetic data, using prior information about the rate of change of the geomagnetic field. We conclude that the palaeomagnetic data are incompatible with the previously suggested short duration (under 100 years) of the shield-building phase and suggest instead a range of 150-450 years, when also accounting for the available radiocarbon ages. Given these results, this has implications for the timing, and thus impact of possible future eruptions in the AVF.

New Zealand's largest city, Auckland, is situated within the basaltic Auckland Volcanic Field (AVF). Therefore, understanding the eruption history of the local volcanoes in the field is of great importance in order to assess future hazards that they may pose. Rangitoto is the youngest and largest volcano in the AVF, although the timing of the first eruption and the duration of the volcanic activity are still uncertain. Here, we use palaeomagnetic methods to provide additional constraints to the duration of the main shield-building phase of Rangitoto, previously estimated to have lasted either less than 100 years or approximately 1000 years. Lava flow samples from an -140 m length vertically oriented drill core produced 203 palaeoinclinations and 74 palaeointensity estimates. Our results show significant variation in both inclination (up to 30 degrees) and intensities (which fall between 25 and 60 & mu;T; present day field values for Auckland are -55 & mu;T). Potential non-geomagnetic explanations for these variations, including thermochemical processes and rheological deformation are discussed. A statistical model was created to determine the minimum duration for the construction of Rangitoto that is compatible with the variations in the palaeomagnetic data, using prior information about the rate of change of the geomagnetic field. We conclude that the palaeomagnetic data are incompatible with the previously suggested short duration (under 100 years) of the shield-building phase and suggest instead a range of 150-450 years, when also accounting for the available radiocarbon ages. Given these results, this has implications for the timing, and thus impact of possible future eruptions in the AVF.

New Zealand's largest city, Auckland, is situated within the basaltic Auckland Volcanic Field (AVF). Therefore, understanding the eruption history of the local volcanoes in the field is of great importance in order to assess future hazards that they may pose. Rangitoto is the youngest and largest volcano in the AVF, although the timing of the first eruption and the duration of the volcanic activity are still uncertain. Here, we use palaeomagnetic methods to provide additional constraints to the duration of the main shield-building phase of Rangitoto, previously estimated to have lasted either less than 100 years or approximately 1000 years. Lava flow samples from an -140 m length vertically oriented drill core produced 203 palaeoinclinations and 74 palaeointensity estimates. Our results show significant variation in both inclination (up to 30 degrees) and intensities (which fall between 25 and 60 & mu;T; present day field values for Auckland are -55 & mu;T). Potential non-geomagnetic explanations for these variations, including thermochemical processes and rheological deformation are discussed. A statistical model was created to determine the minimum duration for the construction of Rangitoto that is compatible with the variations in the palaeomagnetic data, using prior information about the rate of change of the geomagnetic field. We conclude that the palaeomagnetic data are incompatible with the previously suggested short duration (under 100 years) of the shield-building phase and suggest instead a range of 150-450 years, when also accounting for the available radiocarbon ages. Given these results, this has implications for the timing, and thus impact of possible future eruptions in the AVF.

Syneruptive magma mixing is widespread in volcanic eruptions, affecting explosivity and composition of products, but its evidence in basaltic systems is usually cryptic. Here we report direct evidence of mixing between basanitic and tephritic magmas in the first days of the 2021 Tajogaite eruption of Cumbre Vieja, La Palma. Groundmass glass in tephritic tephra from the fifth day of the eruption is locally inhomogeneous, showing micron-scale filamentary structures of Si-poor and Fe-, Mg-rich melt, forming complex filaments attached to bubbles. Their compositional distribution attests the presence of primitive basanitic magma, with compositions similar to late-erupted melts, interacting with an evolved tephritic melt during the first week of the event. From filament morphology, we suggest their generation by dragging and folding of basanitic melt during bubble migration through melt interfaces. Semi-quantitative diffusion modelling indicates that the filamentary structures are short-lived, dissipating in timescales of tens of seconds. In combination with thermobarometric constraints, we suggest a mixing onset by sub-Moho remobilization of a tephritic reservoir by basanite input, followed by turbulent ascent of a mingled magma. In the shallow conduit or lava fountain, bubble nucleation and migration triggered further mingling of the distinct melt-phases. This phenomenon might have enhanced the explosive behaviour of the eruption in such period, where violent strombolian explosions were common.

Integrating multi-parameter observations of volcanic processes is crucial for volcano monitoring. Qualitative models demonstrate that combining observations of volcanic deformation, gas emissions, and other parameters enhances the detection of volcanic unrest and provide insights into the magma plumbing system. Despite the progress made in this field, quantitative models that link these observations are still lacking. Thermodynamic models have been used to constrain the characteristics of magma properties and its plumbing system. In this thesis, I develop models based on melt inclusion data and thermodynamics to reconstruct magma properties such as compressibility, and investigate how magmatic volatile content and magma storage conditions influence observations of volcanic deformation and SO2 degassing. By comparing mafic systems in arc and ocean island settings, I provide evidence for the lack of deformation observed during water-rich arc eruptions. In contrast, despite having low magmatic volatile content, ocean island eruptions have high SO2 emissions due to their high diffusivity, which results in co-eruptive degassing. By comparing model predictions and observations, I show that all magmatic systems experience a certain degree of outgassing prior to an eruption, consistent with current conceptual models of transcrustal magmatic systems. Additionally, integrating time series of deformation, degassing, and extrusion flux can reveal the evolution of magma properties. Using this framework, I provide evidence for the increase in bulk magma compressibility following the removal of the degassed magma during the 2004 eruption of Mount St. Helens. This study contributes to the better understanding of the effects of magmatic volatile content and pre-eruptive gas segregation on the physicochemical properties of magma, and provides a framework for modelling magma prop

Anak Krakatau Volcano is an active volcano located in the Krakatau Complex, Sunda Strait, Indonesia. On 22 December 2018, the volcano experienced a major eruption that led to a tsunami that devastated the shores of the islands of Java and Sumatra and killed up to 437 people. The eruption also destroyed the volcano’s body and change its shape drastically and forming a large crater in the southwestern part. After that eruption, the volcano continues to grow up. This research aims to analyze the deformation of the Anak Krakatau Volcano post-2018 eruption by using the differential interferometry SAR method (DInSAR). In order to support the analysis, we additionally compare the DInSAR result with tectonic-volcanic activity. Sentinel 1-A type SLC satellite imagery data from 5 June 2019 to 7 January 2020; consisting of 19 images or 18 pairs as master and slave were used to producing a deformation map. DInSAR result shows the volcano was generally experiencing deflation during the period, ranging from -1.03 to -4.81 cm (-3.01 cm average). However, inflation also occurred ranging from 0 to 5.99 cm, correlating with shallow and deep volcanic activity and followed by eruptions in October 2019 when the highest activities were observed. Furthermore, coherence value should be highly considered along with DInSAR processing, and this research allows that coherence to be acceptable.

Anak Krakatau Volcano is an active volcano located in the Krakatau Complex, Sunda Strait, Indonesia. On 22 December 2018, the volcano experienced a major eruption that led to a tsunami that devastated the shores of the islands of Java and Sumatra and killed up to 437 people. The eruption also destroyed the volcano’s body and change its shape drastically and forming a large crater in the southwestern part. After that eruption, the volcano continues to grow up. This research aims to analyze the deformation of the Anak Krakatau Volcano post-2018 eruption by using the differential interferometry SAR method (DInSAR). In order to support the analysis, we additionally compare the DInSAR result with tectonic-volcanic activity. Sentinel 1-A type SLC satellite imagery data from 5 June 2019 to 7 January 2020; consisting of 19 images or 18 pairs as master and slave were used to producing a deformation map. DInSAR result shows the volcano was generally experiencing deflation during the period, ranging from -1.03 to -4.81 cm (-3.01 cm average). However, inflation also occurred ranging from 0 to 5.99 cm, correlating with shallow and deep volcanic activity and followed by eruptions in October 2019 when the highest activities were observed. Furthermore, coherence value should be highly considered along with DInSAR processing, and this research allows that coherence to be acceptable.

New Zealand's largest city, Auckland, is situated within the basaltic Auckland Volcanic Field (AVF). Therefore, understanding the eruption history of the local volcanoes in the field is of great importance in order to assess future hazards that they may pose. Rangitoto is the youngest and largest volcano in the AVF, although the timing of the first eruption and the duration of the volcanic activity are still uncertain. Here, we use palaeomagnetic methods to provide additional constraints to the duration of the main shield-building phase of Rangitoto, previously estimated to have lasted either less than 100 years or approximately 1000 years. Lava flow samples from an -140 m length vertically oriented drill core produced 203 palaeoinclinations and 74 palaeointensity estimates. Our results show significant variation in both inclination (up to 30 degrees) and intensities (which fall between 25 and 60 & mu;T; present day field values for Auckland are -55 & mu;T). Potential non-geomagnetic explanations for these variations, including thermochemical processes and rheological deformation are discussed. A statistical model was created to determine the minimum duration for the construction of Rangitoto that is compatible with the variations in the palaeomagnetic data, using prior information about the rate of change of the geomagnetic field. We conclude that the palaeomagnetic data are incompatible with the previously suggested short duration (under 100 years) of the shield-building phase and suggest instead a range of 150-450 years, when also accounting for the available radiocarbon ages. Given these results, this has implications for the timing, and thus impact of possible future eruptions in the AVF.

Syneruptive magma mixing is widespread in volcanic eruptions, affecting explosivity and composition of products, but its evidence in basaltic systems is usually cryptic. Here we report direct evidence of mixing between basanitic and tephritic magmas in the first days of the 2021 Tajogaite eruption of Cumbre Vieja, La Palma. Groundmass glass in tephritic tephra from the fifth day of the eruption is locally inhomogeneous, showing micron-scale filamentary structures of Si-poor and Fe-, Mg-rich melt, forming complex filaments attached to bubbles. Their compositional distribution attests the presence of primitive basanitic magma, with compositions similar to late-erupted melts, interacting with an evolved tephritic melt during the first week of the event. From filament morphology, we suggest their generation by dragging and folding of basanitic melt during bubble migration through melt interfaces. Semi-quantitative diffusion modelling indicates that the filamentary structures are short-lived, dissipating in timescales of tens of seconds. In combination with thermobarometric constraints, we suggest a mixing onset by sub-Moho remobilization of a tephritic reservoir by basanite input, followed by turbulent ascent of a mingled magma. In the shallow conduit or lava fountain, bubble nucleation and migration triggered further mingling of the distinct melt-phases. This phenomenon might have enhanced the explosive behaviour of the eruption in such period, where violent strombolian explosions were common.

Considering the current coral reef crisis and given the conservation priority of tropical reefs, better understanding of the drivers shaping ecological coral reef resilience is required to direct contemporary management strategies. Despite the relevance of volcanic impacts in shaping coral development throughout evolution, they have received little scientific attention. Here, selected case studies are presented to identify and describe unifying patterns of volcanic implications on coral reef communities. An important volcanic hazard affecting coral reefs is material deposition from tephra fallout, pyroclastic currents, and lava flows. Volcanic activities can directly impact coral reefs by material deposition during eruptive periods, and subsequently alter habitat conditions from local to global scales. Related changes affect water quality and substrate characteristics. Coral reefs cannot form on loose volcanic substrates, whereas stable volcanic bedrock provides important shallow-water habitats to corals and other reef organisms. Volcanically-induced habitat changes may persist for months to millennia depending on hazard intensities, ecological reef state, species composition, and environmental conditions. However, coral communities are able to recover from volcanic impacts and in some instances, can even enhance local reef biodiversity and stimulate species turnover. In this study, critical hazard thresholds of coral reef responses to volcanic impacts from tephra deposition are defined. Integrating those references into probabilistic tephra fall modelling in the Coral Triangle (CT) allowed for hazard quantification in space and time. The CT is a global hotspot of marine biodiversity alongside active volcanism hosts some of the most diverse coral reef communities. In this region, over 42% of coral reefs are likely to be affected by light volcanic impacts within 1,000 years. However, the probabilities for most severe events with tephra deposition of 30 cm and the pot

Volcanic eruptions caused by magma-water interaction depend on the substrate, the hydrogeological parameters of the aquifer and the proportions and extent to which magma and water interact. The substrate also affects the resulting overall shape of the volcano and gives rise to a wide range of morphologies. The Puig de la Banya del Boc (PBB), which belongs to the Garrotxa Volcanic Field (GVF), is a monogenetic cone with a complex eruptive succession with phreatomagmatic, Strombolian and effusive phases. Deposits from this volcano reflect the clear influence of the substrate on the eruptive dynamics highlighting how this type of activity is not uncommon in the GVF. 30/1/23, 13:48 Resúmenes https://raugm.org.mx/paricutin80/resumenes/account/view.php?abstractID=43 2/2 The aim of the study consists on the reconstruction of the eruptive history of the PBB volcano through lithostratigraphic, sedimentological and stratigraphic analysis of its deposits. The results show that the PBB volcano and its contemporary Clot de l¿Omera maar-crater are located on a conjugate faults system. Both volcanoes formed during the same eruption that was controlled by the interaction of magma with shallow water tables at different depths in the Paleozoic substrate. These crystalline materials are characterized by low permeability and an irregular distribution of internal heterogeneities such as fractures, schistosity, and the presence of dikes. This resulted in an irregular accumulation of groundwater that yielded an irregular magma/water interaction during the eruption. This demonstrates how a single eruption can produce a complex sequence of eruptive styles and depositional processes. The Puig de la Banya del Boc eruption affected an area of at least 15 km2. Deposits include dense and dilute PDCs, ash fall and lava flows up to 2 km from the vent. This work represents a further step to improve the knowledge of phreatomagmatism and the related hazards in the GVF.

Volcanic eruptions related to monogenetic fields are commonly underestimated in terms of potential hazard because of their small volumes and long periods of inactivity, giving a false perception of volcanic risk to the population. However, this type of eruptions with high uncertainty about the location of a new eruptive vent and lack of preparation for a possible volcanic crisis represents an important phenomenon that needs to be attended. This research aims at assessing the vulnerability of the population facing volcanic hazards in the city of Olot and the perception of a possible new monogenetic eruption, in order to manage evacuation planning and volcanic risk prevention. Olot is the capital city of the Garrotxa region and one of the most important municipalities of Catalonia. This city is located in the Garrotxa Volcanic Field (GVF), a Quaternary alkaline volcanic province that forms part of the European Cenozoic Rift System. Olot represents a good example of how a population has expanded around monogenetic volcanoes. That is why we have assessed the vulnerability and risk levels for four relevant issues, for each volcanic hazard (ash fall, pyroclastic volcanic flow, and lava flows), including 1) social, 2) physical, (3) territorial, and (4) economical components. Regarding the risk perception in the community, face-to-face interviews were established with local residents and authorities. Social, Physical, Territorial and Economic thematic risk maps were obtained. In addition, we analyzed the evacuation route options and the perception of the community regarding the potential volcanic scenarios. This work improves the knowledge and the link between society and volcanic hazards, providing new tools to assess the community for a possible volcanic crisis in an active monogenetic volcanic field in Europe

Interdisciplinary digital twins are becoming able to mimic the different Earth system domains with unrivalled precision, providing analyses, forecasts, uncertainty quantification, and ¿what if¿ scenarios for natural and anthropogenic hazards from their genesis to propagation and impacts. The EU DT-GEO project (2022-2025) is deploying a prototype digital twin on geophysical extremes consisting of interrelated Digital Twin Components (DTCs), intended as self-contained containerised entities embedding simulation codes, Artificial Intelligence (AI) layers, large volumes of nearly-real-time data streams, data assimilation methodologies, and overarching workflows for deployment and execution of single or coupled DTCs in centralised High Performance Computing (HPC) and virtual cloud computing Research Infrastructures (RIs). These DTCs, actually a first step towards a digital twin on Geophysical Extremes integrated in the Destination Earth (DestinE) initiative, will deal with geohazards from earthquakes, volcanoes, and tsunamis by harnessing world-class computational (EuroHPC) and data (EPOS) Research Infrastructures, operational monitoring networks, and leading-edge research and academia partnerships. In particular, 4 DTCs of the 12 in DT-GEO will address different volcanic hazards. DTC-V1 will merge multi-parametric data from ground- based and remote observation systems (on-site monitoring networks and satellites) with global modelling of magma and rock dynamics and with AI approach. DTC-V2 will merge real-time geostationary satellite observations with the FALL3D model using the on-line data assimilation PDAF system to generate deterministic and ensemble-based probabilistic forecast products. DTC-V3 will merge real-time multi- parametric data from ground-based and remote observation systems with deterministic modelling of lava flow propagation and inundation areas including Bayesian modelling of vent opening. Finally, DTC-V4 will consider air-quality data and AI in a gas

Within the framework of ChEESE (Center of Excellence for Exascale in Solid Earth) we created an optimized HPC-based workflow coined PVHA_HPC-WF to develop Probabilistic Volcanic Hazard Assessment (PVHA) for a specific volcano. Increasing the computational capabilities of current PVHA products, PVHA_HPC-WF provides probability and hazard maps, with uncertainty, for tephra fallout at ground and airborne ash concentration and time-persistence at strategic flight levels, exploring the natural variability in Eruptive Source Parameters (ESPs) and wind conditions through a large number of ash dispersal simulations with the model Fall3D. Among other tests, we showcased the workflow through a live exercise for Campi Flegrei, proving the feasibility and usefulness for end-users, such as the Centre of Competence of the Italian Civil Protection PLINIVS and ARISTOTLE, of such hazard evaluations to produce useful short-term impact assessment of tephra ground load at the scale of a country, in particular over mobility networks (road, railways, seaports and airports) and electrical networks, in an operational environment, dealing with real- time performance-distributed workflow. We ran 300 large-scale and high-resolution tephra dispersal simulations with the Flagship code Fall3D on MareNostrum at BSC fetching weather forecast from GFS, and we processed them on the computer cluster ADA at the Istituto Nazionale di Geofisica e Vulcanologia (INGV) of Bologna fetching real-time monitoring data from Osservatorio Vesuviano surveillance system. Results show the ability of the PVHA_HPC-WF to perform PVHA in a reasonable time, with a sufficient level of detail, and therefore its usefulness for civil protection officials and society in reliably assessing volcanic hazard.

In recent years, there has been a growing interest in ensemble-based based approaches for modeling volcanic plumes. The development of advanced ensemble modeling techniques enables the exploration of novel methods for the incorporation of real observations into tephra dispersal models using ensemble- based data assimilation techniques. However, traditional data assimilation algorithms, including ensemble Kalman filter methods, can yield suboptimal state estimates for positive-definite variables such as volcanic aerosols and tephra deposits. We present two new ensemble-based data assimilation techniques for semi- positive-definite variables with highly skewed uncertainty distributions, such as deposit mass loading. The proposed methods are applied to reconstruct the tephra fallout deposit resulting from the 2015 Calbuco eruption and the 946 CE eruption of Baekdu volcano, the so-called Millennium eruption, one of the largest eruptions in historic times based on widespread tephra dispersal. The FALL3D dispersal model was used to perform an ensemble of runs in order to simulate the transport and deposition of tephra for different model configurations. Subsequently, deposit thickness measurements are assimilated to reconstruct the tephra deposit and improve the first-guess results, obtained from a simple ensemble forecast. An assessment of the assimilation methods is carried out using an independent dataset of observations in terms of different evaluation metrics. The methodologies presented here represent promising alternatives for the assimilation of real observations in operational models.

During the European Commission-funded project EUROVOLC, our team has created an interactive webpage to collect citizen-science observations of volcanic events, and to visualise, map and download previously collected data.

The characterisation of the past behavior of a volcanic system (e.g. eruption magnitude, recurrence, location, etc.) is a necessary first step in volcanic hazard assessment and evaluation of related uncertainties of future events. These records are obtained in different ways: field-based geological studies, in case of ancient and preserved deposits, historical observations, for more recent events, or multi parametric geophysical monitoring, which provides in situ eruption information. The multiplicity of data sources yields to heterogeneous information from the past, not only in the number of the events and their characteristics but also in the completeness of records across the timeline. Additionally, the reconstruction of past events based on the actual ranking of explosivity, becomes challenging in volcanoes considered effusive. The current classification of the eruptions links volumes and column height in a proportional-incremental relation, which means, if volume increases, the column height escalates as well. Additionally, the size of the plume height could be linked to more than one classification, diffusing the clear frontier between effusive- dominated or explosive-dominated events. The Canary Islands volcanoes are examples of environments where the big volumes of ejected material are not always associated with big ash plumes. A study based on the eruption energy balance and partition and the use of volcano analogues to complement record gaps can provide an alternative approach in volcanic settings displaying combined effusive and explosive events. The energy balance and partition can be converted into energy-based Probability Density Functions (EPDFs). Likewise, the EPDFs are capable of being fragmented into energy released by different volcano products. In the case of volcanoes with limited historical record, such as Canary Islands (Tenerife, La Palma, El Hierro, Lanzarote), the EPDF of one or many analogue volcanoes can be used and adjusted to describe t

We present a model for the petrogenesis of magma with adakitic affinity in an old subduction zone, which does not involve slab melting and is constrained by new geochronological and geochemical data for Mt. Popa, the largest of three Quaternary volcanoes in central Myanmar (Popa, Monywa and Singu). The edifice is composed of Popa Plateau (0.8–0.6 Ma) with high-K rocks and a stratovolcano (< 0.33 Ma) predominantly composed of medium-K rocks with adakitic affinity (Mg# 45–63, Sr/Y > 40). The distinct K contents indicate that the adakitic magmas cannot be derived from Popa high-K rocks, but they share trace-element signatures and Sr–Nd isotope ratios with medium-K basalts from Monywa volcano. Our estimation of water contents in Popa magma reveals that primary magma for medium-K basalts was generated by partial melting of wedge mantle with normal potential temperature (TP 1330–1340 °C) under wet conditions (H₂O 0.25–0.54 wt%). Its melting was probably induced by asthenospheric upwelling that is recognized by tomographic images. Mafic adakitic magma (Mg# ~ 63, Sr/Y ~ 64) was derived from the medium-K basaltic magma in fractional crystallization of a garnet-bearing assemblage at high pressure, and felsic adakitic rocks (Mg# ~ 45, Sr/Y ~ 50) were produced by assimilation-fractional crystallization processes at mid-crustal depths.

Around once every millenium, a large magnitude explosive eruption occurs on Earth dispersing volcanic ash across millions of square kilometers. Volcanic ash uniquely poses a wide-range of hazards to human health, infrastructure and the environment, the impacts of which are felt close to source to >1000’s of km from the volcano. Importantly for large eruptions, the removal of the ash is almost impossible, which means the material remains and is remobilised in the environment, posing secondary hazards for 100’s of years after the initial eruption. Here I present a study of the processes the produce, transport and deposit ash from large eruptions. I use the ~7.7 ka climactic eruption of Mount Mazama as a case study because the tephra was predominantly deposited on-land facilitating widespread data collection. I collate locations where the Mazama tephra has been recorded to produce a new isopach map and estimate of the total erupted volume (176 km3 bulk or 61 km3 Dense-Rock-Equivalent). The compilation of tephra thickness data also showed how the Mazama tephra deposit has been remobilised through time, exemplifying the uncertainties associated with field data. Remobilised deposits also provide insight into the types of secondary ash hazards that persist following large magnitude eruptions. I also investigate the physical and chemical properties of Mazama ash to provide insight into eruptive processes such as co-PDC plumes and distal ash transport. I determine from the composition of Fe-Ti oxides, that the distal ash can be attributed to the later stages of the climactic Mazama eruption. I also observe that the Grain Size Distribution (GSD) of the distal Mazama tephra is remarkably stable, a trend that is observed for other large distal deposits. This study also investigates the methods we use to analyse grain size in volcanology and outlines a new protocol for measuring the size and shape of volcanic ash using Dynam

Kimberlites are rare, small volume ultramafic igneous rocks found on every continent on Earth, with eruption ages spanning almost 3 billion years. These rocks are derived from the deepest magmas that reach Earth’s surface (>150-200 km) and provide unique insights into the nature of the convecting mantle. In addition, their cargo of entrained mantle xenocrysts (including diamonds) and xenoliths permit examination of the subcontinental lithospheric mantle (SCLM), while ‘deep’ diamonds give insights into the composition of the underlying asthenospheric mantle. Despite their significant scientific and economic importance, and decades of research, particularly in regions of southern Africa, North America and Siberia, questions remain as to the petrogenesis of kimberlites. Contention persists around the depth of origin of kimberlites, melting trigger(s) including tectonic settings, and the composition and evolution of kimberlite melts during their ascent. To provide new insights on these issues, this study presents a comprehensive petrographic, geochemical and geochronological investigation on samples from three occurrences of kimberlite and related magmatism in Finland, comprising the Lentiira-Kuhmo cluster of olivine lamproites, Kuusamo cluster of kimberlites and ultramafic lamprophyres (UMLs) and the Kaavi-Kuopio kimberlites. Finland represents an optimal location for testing various petrogenetic models, particularly regarding the links to geodynamic processes as the tectonic evolution of the Baltic Shield and its role in supercontinent cycles are well constrained. This work presents the first petrological account of the Kuusamo kimberlites, revealing that they represent highly differentiated magmas with scarce olivine macrocrysts and other mantle-derived xenocrysts. These characteristics contrast with the neighbouring Kaavi-Kuopio kimberlites, which are inferred to have crystallised from less differentiated magmas that were modified by mantle assimilation, as evidence

Around once every millenium, a large magnitude explosive eruption occurs on Earth dispersing volcanic ash across millions of square kilometers. Volcanic ash uniquely poses a wide-range of hazards to human health, infrastructure and the environment, the impacts of which are felt close to source to >1000’s of km from the volcano. Importantly for large eruptions, the removal of the ash is almost impossible, which means the material remains and is remobilised in the environment, posing secondary hazards for 100’s of years after the initial eruption. Here I present a study of the processes the produce, transport and deposit ash from large eruptions. I use the ~7.7 ka climactic eruption of Mount Mazama as a case study because the tephra was predominantly deposited on-land facilitating widespread data collection. I collate locations where the Mazama tephra has been recorded to produce a new isopach map and estimate of the total erupted volume (176 km3 bulk or 61 km3 Dense-Rock-Equivalent). The compilation of tephra thickness data also showed how the Mazama tephra deposit has been remobilised through time, exemplifying the uncertainties associated with field data. Remobilised deposits also provide insight into the types of secondary ash hazards that persist following large magnitude eruptions. I also investigate the physical and chemical properties of Mazama ash to provide insight into eruptive processes such as co-PDC plumes and distal ash transport. I determine from the composition of Fe-Ti oxides, that the distal ash can be attributed to the later stages of the climactic Mazama eruption. I also observe that the Grain Size Distribution (GSD) of the distal Mazama tephra is remarkably stable, a trend that is observed for other large distal deposits. This study also investigates the methods we use to analyse grain size in volcanology and outlines a new protocol for measuring the size and shape of volcanic ash using Dynam

Tephra layers preserved in marine sediments are strong tools to study the frequency, magnitude and source of past major explosive eruptions. Thirty-seven volcanoes from the Ecuadorian and Colombian arc, in the northern Andes, experienced at least one eruption during the Holocene. The volcanic hazard is therefore particularly high for the populated areas of the Andes and in particular cases for the coastal region, and it is crucial to document such events to improve hazard assessment. The age and distribution of deposits from major Holocene eruptions have been studied in the Cordillera, but no descriptions of distal fallouts have been published. In this study we focused on 28 Holocene tephra layers recorded in marine sediment cores collected along the northern Ecuador - southern Colombia margin. New lithological, geochemical and isotope data together with 14C datings on foraminifers allow us to determine the age and volcanic source of marine tephra, and to propose a first land-sea correlation of distal tephra fallouts. We show that at least seven explosive eruptions from Guagua Pichincha, Atacazo-Ninahuilca, Cotopaxi, and Cerro Machín volcanoes left tephra deposits recorded in marine cores over 250 km away from their source. Volume estimates of emitted tephra range between 1.3 and 6.0 km3 for the 10th century Guagua Pichincha, ∼5 ka Atacazo-Ninahuilca, ∼6.7 and ∼7.9 ka Cotopaxi events, suggesting that they were eruptions of Volcanic Explosivity Index of 5. The distribution of these deposits also brings new constraints for a better evaluation of the volcanic hazard in Ecuador. Key Points We propose a first land-sea correlation of distal Holocene tephra off Ecuador based on 14C age and geochemical data Products from at least seven explosive Holocene eruptions in Ecuador and south Colombia reached the Pacific Ocean Volumes of tephra emitted by largest eruptions vary between 1.3 and 6.0 km3, suggesting they were VEI-5 eruptions Plain Language Summary During major explosi

Archived are Magnetic and LiDAR data collected at Lava Beds National Monument by the NASA funded TUBEX project (Dr. Kelsey Young – PI) in 2017 and 2018. The archived data are for a paper submitted to a JGR Planets special issue on Exploring Planetary Caves as Windows into Subsurface Geology, Habitability, and Astrology with the title: Field Mapping and Modeling of Terrestrial Lava Tube Magnetic Anomalies as an Analog for Lunar Lava Tube Exploration and Prospecting. We use observed data and detailed magnetic models to understand the practicality of mapping magnetic anomalies to determine lava tube locations and internal geometries within a lava flow.

Refinements of the geological timescale driven by the increasing precision and accuracy of radiometric dating have revealed an apparent correlation between large igneous provinces (LIPs) and intervals of Phanerozoic faunal turnover that has been much discussed at a qualitative level. However, the extent to which such correlations are likely to occur by chance has yet to be quantitatively tested, and other kill mechanisms have been suggested for many mass extinctions. Here, we show that the degree of temporal correlation between continental LIPs and faunal turnover in the Phanerozoic is unlikely to occur by chance, suggesting a causal relationship linking extinctions and continental flood basalts. The relationship is stronger for LIPs with higher estimated eruptive rates and for stage boundaries with higher extinction magnitudes. This suggests LIP magma degassing as a primary kill mechanism for mass extinctions and other intervals of faunal turnover, which may be related to [Formula: see text], Cl, and F release. Our results suggest continental LIPs as a major, direct driver of extinctions throughout the Phanerozoic.

Tephra layers preserved in marine sediments are strong tools to study the frequency, magnitude and source of past major explosive eruptions. Thirty-seven volcanoes from the Ecuadorian and Colombian arc, in the northern Andes, experienced at least one eruption during the Holocene. The volcanic hazard is therefore particularly high for the populated areas of the Andes and in particular cases for the coastal region, and it is crucial to document such events to improve hazard assessment. The age and distribution of deposits from major Holocene eruptions have been studied in the Cordillera, but no descriptions of distal fallouts have been published. In this study we focused on 28 Holocene tephra layers recorded in marine sediment cores collected along the northern Ecuador - southern Colombia margin. New lithological, geochemical and isotope data together with 14C datings on foraminifers allow us to determine the age and volcanic source of marine tephra, and to propose a first land-sea correlation of distal tephra fallouts. We show that at least seven explosive eruptions from Guagua Pichincha, Atacazo-Ninahuilca, Cotopaxi, and Cerro Machín volcanoes left tephra deposits recorded in marine cores over 250 km away from their source. Volume estimates of emitted tephra range between 1.3 and 6.0 km3 for the 10th century Guagua Pichincha, ∼5 ka Atacazo-Ninahuilca, ∼6.7 and ∼7.9 ka Cotopaxi events, suggesting that they were eruptions of Volcanic Explosivity Index of 5. The distribution of these deposits also brings new constraints for a better evaluation of the volcanic hazard in Ecuador. Key Points We propose a first land-sea correlation of distal Holocene tephra off Ecuador based on 14C age and geochemical data Products from at least seven explosive Holocene eruptions in Ecuador and south Colombia reached the Pacific Ocean Volumes of tephra emitted by largest eruptions vary between 1.3 and 6.0 km3, suggesting they were VEI-5 eruptions Plain Language Summary During major explosi

A 300 meter sequence of Pleistocene turbidite deposits was recovered on the Nazca Plate at the subducting edge of the Peru-Chile Trench at ODP Site 1232. Analysis of the coarsest particles in the turbidite sequences implies sediment was supplied in some proportion by terrestrial erosion and originated in the coastal, central, and Andean volcanic/magmatic belt which parallels the Southern Chilean coast, and the predominant material type is volcanic. Petrographic and geochemical analyses show that samples from 3 - 140 mbsf contain >43% fresh, angular glass. New calcareous nannofossil biostratigraphy brackets the sediment ages of the upper 288 m of cored section to between 12.47 kyr and 275 kyr. Glass compositional analyses and comparisons with geochemical data from surrounding volcanic sources in southern Chile indicate the volcanic glasses within Site 1232 turbidites originate from a single source. Elemental analyses of individual glass shards show a geochemical signature consistent with origination within the adjacent Andean Southern Volcanic Zone. Similarities in the incompatible element averages and a strong correlation of trace element ratios coincide with published data from the Central Southern Volcanic Zone (CSVZ), more specifically the Puyehue-Cordon Caulle volcanic complex (PCCVC). Investigation into potential transport processes in Coastal Chile from the CSVZ to Site 1232 reveal that with the distance traveled (>250 km), the Site 1232 turbidites are likely to have experienced multiple transport methods. With the lack of turbidite deposition in the Holocene, despite the consistency of sediment delivered to the continental shelf by adjacent rivers, it is unlikely that the Site 1232 sediments were deposited onto the continental shelf solely by fluvial transport. Glacial shifts in wind patterns and ice distribution likely played a strong role in the dispersal and deposition of the glass shards. Understanding the origin and of the Site 1232 glass shards and how

Effusive eruption products, specifically lava flow-fields, can provide an important window into the geologic history of planetary bodies. This dissertation investigates the geomorphological characteristics of volcanic terrains formed by effusive volcanism to infer eruption dynamics, and, in the planetary context, the magmatic and volcanic evolution of Mars. We investigate the 2014-2015 Holuhraun lava flow-field in the Icelandic highlands and the youngest volcanic terrain on Mars-Elysium Planitia-with a multi-faceted approach of surface and subsurface characterizations, based on remote sensing data, including orthomoasics, Digital Terrain Models (DTMs), and subsurface radar products. To better understand effusive eruption products and quantify their controls, we begin by examining the 2014-2015 Holuhraun eruption site using a combination of remote sensing data and ground-truth field observations from the summers of 2015-2019. This part of the dissertation includes three complementary investigations. First, a detailed characterization of the lava flow morphologies (i.e. lava facies) shows that the lava flow-field is dominated by transitional lava types including, rubbly pahoehoe, slabby pahoehoe, and spiny pahoehoe, instead of traditional pahoehoe and 'a'a lava types. Second, we investigated surface roughness of the entire lava flow-field to evaluate if root-mean-square (RMS) height deviation, Hurst exponents, and breakpoints can be used to distinguish between different lava facies in DTMs with pixel scales of 0.05 to 0.5 m/pixel. Our findings show that most lava facies are indistinguishable by surface roughness characteristics down to a 5 cm baseline and thus, despite this metric being commonly used, surface roughness is a poor discriminator to uniquely identify transitional lava types based on remote sensing data. Third, to address the scientific gap of understanding the controls on lava morphologies, the 2014-2015 Holuhraun eruption was then examined to test the hy

Recent decades have highlighted the increasing need to connect and strengthen the volcanology community at European level. Indeed, research in the volcanology field is highly qualified in Europe and the volcano monitoring infrastructures have achieved valuable know-how, becoming the state-of-the-art in the world. However, the lack of common good practices in sciences and technologies, missing standards, as well as a significant fragmentation of the community requires coordination to move forward and guarantee a trans-national harmonisation. The European Plate Observing System (EPOS) represented the first opportunity to initiate this process of coordination by encouraging the creation of a European volcanological scientific infrastructure for data and service sharing. During the preparation and the design of EPOS, the volcanology community identified the objectives and the needs of the community building, the services to be provided and the work plan to implement the infrastructure. To achieve this aim, the contribution from three European projects FUTUREVOLC, MED-SUV and EUROVOLC was essential. This paper presents the main steps performed during the last years for building the community and implementing the infrastructure.

Deception Island is one of the most active volcanoes in Antarctica with more than twenty explosive eruptions in the past two centuries. Any future volcanic eruption(s) is a serious concern for scientists and tourists, will be detrimental to marine ecosystems and could have an impact to global oceanographic processes. Currently, it is not possible to carry-out low and high frequency volcanic gas monitoring at Deception Island because of the arduous climatic conditions and its remote location. Helium, neon and argon isotopes measured in olivine samples of the main eruptive events (pre-, syn- and post caldera) offer insights into the processes governing its volcanic history. Our results show that: (i) ascending primitive magmas outgassed volatiles with a MORB-like helium isotopic signature (3He/4He ratio); and (ii) variations in the He isotope ratio, as well as intensive degassing evidenced by fractionated 4He/40Ar* values, occurred before the beginning of the main eruptive episodes. Our results show how the pre-eruptive noble gas signals of volcanic activity is an important step toward a better understanding of the magmatic dynamics and has the potential to improve eruption forecasting.

The January 15th 2022 eruption of the Hunga-Tonga volcano was associated to one of the highest energy volcanic explosions of the past few decades. Here we present a compilation of data from global seismic networks to explore three main topics: the time evolution of the eruption, the propagation of the atmospheric waves around the Earth and the low-frequency, long-lasting seismic signals worldwide after the main event. We find that the eruption started around 04:00, included two large explosions at 05:30 and 08:25 and produced atmospheric waves which circled the Earth more than two times during a time span of 3.5 days and were detected seismically. We also identify very low frequency signals, detected over several hours, which we interpret as resulting from the excitation of Earth normal modes. To our knowledge, there are no previous examples of atmospheric-solid Earth coupling over such a long time interval and only two examples of normal mode excitation following volcanic eruptions.

Archived are Magnetic and LiDAR data collected at Lava Beds National Monument by the NASA funded TUBEX project (Dr. Kelsey Young – PI) in 2017 and 2018. The archived data are for a paper submitted to a JGR Planets special issue on Exploring Planetary Caves as Windows into Subsurface Geology, Habitability, and Astrology with the title: Field Mapping and Modeling of Terrestrial Lava Tube Magnetic Anomalies as an Analog for Lunar Lava Tube Exploration and Prospecting. We use observed data and detailed magnetic models to understand the practicality of mapping magnetic anomalies to determine lava tube locations and internal geometries within a lava flow.

En zonas volcánicas activas, entendiendo como tales aquellas que han tenido alguna erupción durante el Holoceno (aproximadamente en los últimos 11.700 años), el registro geológico nos permite identi ficar estas erupciones y acotar una gran cantidad de parámetros eruptivos. Esta información sirve no sólo para reconstruir las erupciones pasadas, sino que permite predecir, entre otros, el tipo de magma, el estilo eruptivo o el rango de magnitud del evento. En suma, el pasado es la clave del futuro. De esta manera, el registro geológico (particularmente el holoceno) se convierte en una herramienta de gran utilidad para evaluar la peligrosidad del volcanismo activo. En este contexto, un caso de estudio excepcional es la gran erupción del Complejo Volcánico de Cerro Blanco (CVCB), en la Zona Volcánica Central de los Andes, noroeste de Argentina, datada en 4410-4150 a cal AP. Este evento eruptivo es uno de los principales que han ocurrido durante el Holoceno en el mundo (Fernández-Turiel et al. 2019, Osterrieth et al. 2019). El registro geológico investigado en las provincias de Catamarca, Tucumán y Santiago del Estero evidencia una erupción explosiva riolítica que formó depósitos piroclásticos de caída en un área de aproximadamente 500,000 km2, acumulando >100 km3 de tefra (volu- men total bruto, equivalente a unos 70 km 3 de volumen DRE). Este último valor excede el umbral inferior del Índice de Explosión Volcánica (VEI) de 7. Los depósitos de caída cineríticos cubrieron extensas áreas localizadas a más de 400 km de la fuente y los depósitos deflujos piroclásticos inundaron los valles vecinos alcanzando distancias de varias decenas de kilómetros (Báez et al. 2020, Fernández-Turiel et al. 2019). El descubrimiento de la gran erupción holocena del Complejo Volcánico de Cerro Blanco ha puesto de manifiesto que el sur de la Puna es una zona volcánica muy activa y que, como tal, la evaluación de la peligrosidad volcánica debe ser reconsiderada, de la misma manera que las medid

En zonas activas de islas volcánicas oceánicas, entendiendo como tales aquellas que han tenido algu- na erupción durante el Holoceno (aproximadamente en los últimos 11.700 años), el registro geológico nos permite identificar estas erupciones y acotar una gran cantidad de parámetros eruptivos. Esta información sirve no sólo para reconstruir las erupciones pasadas, sino que permite predecir, entre otros, el tipo de magma, el estilo eruptivo o el rango de magnitud del evento. Esta información resulta clave a la hora de evaluar la peligrosidad volcánica en estas zonas de volcanismo activo. Aquí presentamos la investigación del Proyecto LAJIAL, que tiene por objetivo discernir la actividad volcánica subaérea que ha experimentado la isla durante el Holoceno. El nombre del proyecto alude a la toponimia local con el que se conocen los campos de lava en la Isla de El Hierro, Islas Canarias. El volcanismo subaéreo del Holoceno de El Hierro genera campos de volcanes monogenéticos vinculados a los tres sistemas de dorsales o rifts presentes en la isla (Carracedo et al. 2001, Guillou et al. 1996). Sus mecanismos erupti- vos son típicamente estrombolianos, aunque también hay eventos freatostrombolianos. Las erupciones más recientes con frecuencia forman campos de lava en las plataformas costeras, que se consideran posteriores al último máximo glacial (aprox. 20 ka AP). Las plataformas costeras más desarrolladas se encuentran al final de las dorsales y en el interior de la depresión de El Golfo. Este criterio geomorfológico muestra que más de treinta erupciones subaéreas han tenido lugar en El Hierro desde hace aprox. 20 ka AP. Además, hay muchos edificios volcánicos aparentemente recientes lejos de la costa. La investigación del volcanismo más reciente de la isla, los últimos 11.700 años del Holoceno, abarca un período su ficientemente largo y cercano a la actualidad. Por lo tanto, este período es el mejor para modelar los procesos eruptivos que nos permitirán evaluar los escenar

Modelling atmospheric dispersal of volcanic ash and aerosols is becoming increasingly valuable for assessing the potential impacts of explosive volcanic eruptions on buildings, air quality, and aviation. Management of volcanic risk and reduction of aviation impacts can strongly benefit from quantitative forecasting of volcanic ash. However, an accurate prediction of volcanic aerosol concentrations using numerical modelling relies on proper estimations of multiple model parameters which are prone to errors. Uncertainties in key parameters such as eruption column height and physical properties of particles or meteorological fields represent a major source of error affecting the forecast quality. The availability of near-real-time geostationary satellite observations with high spatial and temporal resolutions provides the opportunity to improve forecasts in an operational context by incorporating observations into numerical models. Specifically, ensemble-based filters aim at converting a prior ensemble of system states into an analysis ensemble by assimilating a set of noisy observations. Previous studies dealing with volcanic ash transport have demonstrated that a significant improvement of forecast skill can be achieved by this approach. In this work, we present a new implementation of an ensemble-based data assimilation (DA) method coupling the FALL3D dispersal model and the Parallel Data Assimilation Framework (PDAF). The FALL3D+PDAF system runs in parallel, supports online-coupled DA, and can be efficiently integrated into operational workflows by exploiting high-performance computing (HPC) resources. Two numerical experiments are considered: (i) a twin experiment using an incomplete dataset of synthetic observations of volcanic ash and (ii) an experiment based on the 2019 Raikoke eruption using real observations of SO2 mass loading. An ensemble-based Kalman filtering technique based on the local ensemble transform Kalman filter (LETKF) is used to assimilate satel

Volcanic eruptions are among the most jeopardizing natural events due to their potential impacts on life, assets, and the environment. In particular, atmospheric dispersal of volcanic tephra and aerosols during explosive eruptions poses a serious threat to life and has significant consequences for infrastructures and global aviation safety. The volcanic island of Jan Mayen, located in the North Atlantic under trans-continental air traffic routes, is considered the northernmost active volcanic area in the world with at least five eruptive periods recorded during the last 200 years. However, quantitative hazard assessments on the possible consequences for the air traffic of a future ash-forming eruption at Jan Mayen are nonexistent. This study presents the first comprehensive long-term volcanic hazard assessment for the volcanic island of Jan Mayen in terms of ash dispersal and concentration at different flight levels. In order to delve into the characterization and modeling of that potential impact, a probabilistic approach based on merging a large number of numerical simulations is adopted, varying the volcano's eruption source parameters (ESPs) and meteorological scenario. Each ESP value is randomly sampled following a continuous probability density function (PDF) based on the Jan Mayen geological record. Over 20 years of meteorological data is considered in order to explore the natural variability associated with weather conditions and is used to run thousands of simulations of the ash dispersal model FALL3D on a 2 km resolution grid. The simulated scenarios are combined to produce probability maps of airborne ash concentration, arrival time, and persistence of unfavorable conditions at flight levels 50 and 250 (FL050 and FL250). The resulting maps can serve as an aid during the development of civil protection strategies, to decision-makers and aviation stakeholders, in assessing and preventing the potential impact of a future ash-rich eruption at Jan Mayen.

Le Groupe de Parent est situé dans le Domaine Nord de l’Orogène de l’Ungava (Québec, Canada). Il est constitué de roches volcaniques principalement mafiques à intermédiaires, métamorphisées aux faciès des schistes verts et des amphibolites. Le Domaine Nord, conjointement avec le Domaine Sud, est mieux connu sous le nom de ceinture de Cape Smith, fameuse pour ses gisements de Ni-Cu-EGP. Or, contrairement au Domaine Sud, le Groupe de Parent est très peu documenté. La stratigraphie et l’environnement de formation de la séquence volcanique sont à déterminer, l’âge du Groupe de Parent est mal connu, tout comme sa place dans l’Orogène de l’Ungava. Bien que des minéralisations contiennent des valeurs jusqu’à 189 g/t Au, le Groupe de Parent reste assez peu exploré. En résumé, une amélioration de l’état des connaissances de la région est nécessaire. Pour ce faire, ce projet de recherche sur le Groupe de Parent a été développé en partenariat avec le Ministère de l’Énergie et des Ressources naturelles (MERN) du Québec. Les objectifs étaient de définir des unités lithogéochimiques, d'intégrer ces unités dans une carte géologique précise du feuillet SNRC 35G11 et de préciser le contexte volcanique, pétrologique et tectonique du Groupe de Parent. Les principales méthodes utilisées sont les observations de terrain, de lames minces et de photos d’échantillons prises en conditions contrôlées, la cartographie détaillée d’affleurements clés ainsi que l’interprétation des nouvelles données géochimiques et géochronologiques. Les analyses géochimiques ont été obtenues par méthode conventionnelle ainsi que par l’analyseur portatif à fluorescence de rayons X (pXRF). Dans le feuillet 35G11, le Groupe de Parent est dominé par des basaltes, quelques andésites ainsi qu’une dacite. Parmi les roches mafiques à intermédiaires, trois groupes texturaux ont été distingués : aphyrique (Pa9), porphyrique à pyroxène (Pa10) et polygénique (Pa12). Les roches aphyriques, de composition mafique, sont des l