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The volcanic structure of the Seymour Sewell seamount appears to have formed over a relatively long time in at least two stages. Its main massif was formed as a result of volcanic activity in the axial zone of the Central Indian Ridge about 16.3 Ma ago for about 0.5 Ma. Then the volcanic process temporarily stopped and the seamount drifted 260 km southwest along with the supporting African plate. In the last epoch of direct magnetic polarity (Brunes, 680 ka ago), as a result of a new cycle of volcanotectonic activity, the southeastern segment of the seamount collapsed. At this time, a new portion of magmatic material with a high ferrous mineral content was erupted here, reflected in the more intense magnetic anomaly confined to this part of the seamount. [ABSTRACT FROM AUTHOR]

This paper discusses the data of instrumental observations conducted at the Mikhnevo Observatory, at INTERMAGNET observatories, and at the Geophysical Monitoring Center of the Institute of Geosphere Dynamics (IGD), Russian Academy of Sciences (RAS) during the explosive eruption of Hunga Tonga-Hunga Ha'apai Volcano of January 15, 2022. It is shown that the explosion of the volcano produced a series of wave disturbances in the atmosphere, as well as electrical and magnetic variations at large epicentral distances. The atmospheric disturbances were recorded as Lamb waves emitted by a source at the center of the explosion, as well as by a virtual source situated at the antipode. The latter source was formed by convergence and summing of signals propagating on the terrestrial sphere. In addition to primary waves, the recorded phenomena also include secondary and tertiary waves due to multiple passage of the explosion-produced signal around the terrestrial sphere. We evaluated the source energy based on the characteristic frequency in the spectrum of the signal, resulting in the value ~1018 J, which corresponds to ~200 MT of TNT, when converted to an explosive source. It is shown that a volcanic explosion is accompanied by electrical and magnetic variations both at the time of the explosion and at the time when the recording site receives atmospheric wave disturbances. [ABSTRACT FROM AUTHOR]

This paper reviews the results of fundamental importance achieved by the Institute of Volcanology and Seismology (IV&S), Far East Branch (FEB), Russian Academy of Sciences (RAS) for the period 1962‒2021. We consider the most important achievements classified under the following headings: Volcanological research includes petrologic and geochemical features of ejecta by volcanoes in the Kuril–Kamchatka region; the age of volcanoes and the phases of volcanogenic catastrophism in Kamchatka; hydrothermal systems and geothermal reserves of Kamchatka; hydrothermal metasomatism and volcanogenic mineral generation and mineralization; Geophysical research includes the seismology of volcanoes; deformation at active volcanoes; tectonic earthquakes and tsunamis; the internal structure of volcanic systems. [ABSTRACT FROM AUTHOR]

The paper presents the results of processing recordings of abnormal signals, which originated during the eruption of Hunga Tonga-Hunga Haʻapai volcano, and were registered by a laser nanobarograph and two laser strainmeters; there were three meters of sea-level variations, located in the Sea of Japan, and twelve meters of sea-level variations, located in the Pacific Ocean. Acoustic-gravity Lamb waves, generated in the atmosphere, caused disturbances of similar periods in the Earth's crust, which were registered by laser strainmeters. Atmospheric impulse and Lamb waves during their propagation over the Pacific Ocean and the Sea of Japan initiated meteorological tsunamis in their waters, at periods corresponding to the seiches (Eigen oscillations) of registration stations' location areas. In the records of all sea wave recorders, we did not find signs of a classical tsunami origination, and in the records of laser strainmeters, we did not find signals corresponding to seabed displacements at the point of the volcano explosion that led to the formation of a classical tsunami. [ABSTRACT FROM AUTHOR]

To understand a field of volcanic activity, a survey on the Earth's subsurface structure is helpful. In particular, a magnetotelluric survey can image the subsurface structure necessary for volcanic disaster prevention because it is sensitive to high-temperature areas and areas where fluid and clay minerals exist. In 3-D magnetotelluric inversion using the data observed near volcanoes and the coastline, the topography and sea around the survey area need to be considered. Therefore, constructing a mesh of the analysis area by automatically using topography and bathymetry data is necessary. Additionally, the estimated subsurface structure should be compared to the sources of variation estimated from other physical observations, such as earthquakes, ground deformation, and changes in the geomagnetic total field, for interpretation. This study introduces a simple and easy-to-operate graphical pre- and post-processor developed to support the resistivity structure analysis of a volcano and the nearby coastline. In the developed software, the pre-process indicates the mesh construction, and the post-process indicates result derivation, file construction for the sensitivity tests, and file exportation to compare the inversion results with other measured quantities. This pre- and post-process can be performed easily on the same window of the software. [ABSTRACT FROM AUTHOR]

Mount Pandan is an active volcano with geothermal phenomena and is located in tectonically active East Java, Indonesia. We conducted a geomagnetic study around Mount Pandan to obtain further information about fault structures and geothermal prospects. We established 245 geomagnetic observation stations covering an area of 20 km2. We calculated the magnetic anomalies, applied upward continuation and reduction to the pole, and calculated the improved normalized horizontal tilt angle to interpret the area. Furthermore, modeling was performed that included previous research. Our study identified NW–SE-, SW-NE-, and W-E-trending structures that might be affected by the Kendeng thrust fault and act as pathways for geothermal fluid flow. This geothermal fluid is estimated to flow from the southern area between Mount Pandan and Mount Wilis toward the north. There are several hot springs around Mount Pandan and Tirtohusodo hot spring near Mount Wilis. Thus, the heat source may be located in the area between Mount Pandan and Mount Wilis and supply heat for the geothermal systems of both volcanoes. The modeling results show the intrusion of andesite-type bodies at the summit of Mount Pandan and in the northern part of the study area. We found low magnetic anomalies that might indicate a heated region as a potential geothermal area. The reservoir of the geothermal system in Mount Pandan is interpreted to be tuffaceous sandstone from the Kalibeng Formation with claystone from the Klitik Formation as a clay caprock. [ABSTRACT FROM AUTHOR]

The ocean reduces human impact on the climate by absorbing and sequestering CO2. From 1950s to the 1980s, observations of pCO2 and related ocean carbon variables were sparse and uncertain. Thus, global ocean biogeochemical models (GOBMs) have been the basis for quantifying the ocean carbon sink. The LDEO‐Hybrid Physics Data product (LDEO‐HPD) interpolates sparse surface ocean pCO2 data to global coverage by using GOBMs as priors, and applying machine learning to estimate full‐coverage corrections. The largest component of the GOBM corrections are climatological. This is consistent with recent findings of large seasonal discrepancies in GOBMs, but contrasts the long‐held view that interannual variability is a major source of GOBM error. This supports extension of the LDEO‐HPD pCO2 product back to 1959, using a climatology of model‐observation misfits prior to 1982. Consistent with previous studies for 1980 onward, air‐sea CO2 fluxes for 1959–2020 demonstrate response to atmospheric pCO2 growth and volcanic eruptions. Plain Language Summary: The ocean removes carbon dioxide (CO2) from the atmosphere and reduces climate change caused by humans. The magnitude of this removal can be estimated using computer models of ocean physics, chemistry, and biology, as well as statistical extrapolations of observations. The observational record is too sparse to directly reconstruct air‐sea fluxes prior to 1982, but by combining models and a statistical approach, we make an estimate for 1959‐present that is substantially informed by observations. The LDEO‐Hybrid Physics Data product (LDEO‐HPD) product for air‐sea CO2 exchange includes two periods, with the first previously published for 1982–2018 and extended here to end in 2020, and the second being this extension back in time. For 1959–1981, LDEO‐HPD corrects models using the monthly average of data‐based corrections derived from the observed period, a choice justified by our finding that these monthly means are the largest component of the needed corrections during the observed period. The LDEO‐HPD product agrees much better with independent observations than the models alone, and can be used to understand what controls year to year changes in the ocean carbon sink. Key Points: Climatological deviations of ocean hindcast models from observations are substantially larger than interannual deviationsClimatological correction extends machine learning based hybrid model‐observation product temporally for surface ocean pCO2 (LDEO‐Hybrid Physics Data product)The ocean carbon sink from 1959 to 2020 has responded to atmospheric pCO2 growth and volcanic eruptions [ABSTRACT FROM AUTHOR]

The way people perceive the volcanic risk and how this leads them to take protective measures is an essential topic in volcanology. We apply the Protection Motivation Theory (PMT) to analyse the threat and coping appraisal of individuals living at different distance ranges from Volcán de Colima, Mexico. We assessed respondents' perceived vulnerability, the severity of the volcanic threat, their perception of the efficacy of protection measures, their ability to implement them, and how this influences their level of implementation. We collected data from 224 individual inhabitants from twelve different villages. People living closer to the volcano have a higher threat appraisal but a lower level of implementation of protective measures. Perceived severity of the threat, the efficacy of the recommended measures, and the respondents' self-efficacy were significantly related to the implementation of protective measures. However, the relationship for self-efficacy was strongest. As such, risk management in the Colima area should focus on improving self-efficacy to enhance the implementation of protective measures. Priority should be given to communities closest to the volcano. [ABSTRACT FROM AUTHOR]

The results of instrumental observations for meteoparameters, microbaric variations, and variations in an electric field are analyzed at the Mikhnevo Observatory and the Center for Geophysical Monitoring, Moscow of the Institute of Geospheric Dynamics, Russian Academy of Sciences, as are geomagnetic variations from observatories of the INTERMAGNET network during the explosive eruption of Hunga–Tonga–Hunga–Ha'apai volcano on January 15, 2001. It is shown that the volcanic explosion was accompanied by wave disturbances of the atmosphere and strong variations in the magnetic and electric fields at significant epicentral distances. Together with Lamb waves caused at the explosion epicenter, we registered waves caused by a virtual source located in the antipode, as well as secondary and tertiary direct (from the explosion epicenter) and antipode waves indicating that the wave atmospheric signal skirts the Earth three times. The source energy estimated by the typical frequency in the signal spectrum is ~1018 J, which corresponds to a ~200 Mt TNT explosion with recalculation to the explosive source. It is shown that the volcanic explosion was responsible for the global variations in the electric and magnetic fields. [ABSTRACT FROM AUTHOR]

We used data acquired during field surveys conducted over the years to study the macro component and micro component composition of water in Lake Zelenoe in the Troitsky Crater of active Maly Semyachik Volcano. We showed that the lake contains ultra-acid (pH < 1) water of sulfate–chloride composition with mineral concentrations between 8 and 42 g/L, depending on the state of the volcano. The anion composition of this lake is formed by inflow and subsequent dissolution of acid volcanic gases in an aquifer horizon situated immediately below the lake. The cation composition of the water is controlled by practically congruent dissolution of host rocks. A long period of repose was followed in 2008 by a new phase in the hydrothermal activity of the volcano lasting until today. Upon the background of a constantly increasing volume we observed increasing concentrations of main macro components (SO4, Cl, Al, Fe), and of mineral content in general. [ABSTRACT FROM AUTHOR]

Understanding the response of biomass allocation in current-year twigs is crucial for elucidating the plant life-history strategies under heterogeneous volcanic habitats. We aimed to test whether twig biomass allocation, within-leaf biomass allocation, and the size-number trade-off of Betula platyphylla would be influenced. We measured twig traits of B. platyphylla in Wudalianchi volcanic kipuka, the lava platform, and Shankou lake in northeastern China using standardized major axis analyses. The results showed that the leaf number, total lamina mass (TLAM), stem mass (SM), and twig mass (TM) were significantly different between the three habitats and were greatest in kipuka with abundant soil nutrients. TLAM and SM scaled allometrically with respect to TM, while the normalization constants of the lava platform differ significantly between kipuka and Shankou lake, which showed that under certain TM, leaves gain more biomass in the lava platform. However, within the leaf, individual lamina mass (ILM) scaled isometrically with respect to individual petiole mass (IPM) in kipuka and the lava platform, but ILM scaled allometrically to IPM in Shankou lake. Our results indicated that inhabitats influenced the twig traits and biomass allocation and within-leaf biomass allocation are strategies for plants to adapt to volcanic heterogeneous habitats.

This study aims to identify the potential groundwater in Jedong, Malang, East Java. The hydrogeomorphological approach is a suitable approach to describe the relationship between hydrological and geomorphological processes on and below the earth's surface. The survey of geoelectricity complements the hydrogeomorphological approach. It will give a better description of the groundwater conditions below the earth's surface. Based on the research, there are 2 hydrogeomorphological units in the study area, which are: Volcanic Foot Valley Unit and Volcanic Foot Ridge Unit. The best groundwater potential is in Volcanic Foot Valley Hydrogeomorphological unit, namely Awar-awar Valley and Cokro Valley. The valleys are dominated by gully erosion and landslides. They have surface deposits up to a depth of 7 meters, and lots of outcrops of breccia, pumice, and andesite boulders. The valley’s springs discharge between 56 - 198 m3/day. The average infiltration rate in the valley is 1776 mm / hour, with sandy soil material. The best aquifer consisting of sandy material is more than 10 meters in depth, based on the geoelectrical survey. Water in the aquiclude layer, cannot be exploited because it is breccia and tuff material. The Sawah valley cannot be exploited further because the groundwater potential is very low. This can be identified by the thick water outflow seepage. In the Volcanic Foot Ridge Hydrogeomorphological unit, the groundwater potential is also very small. Hydrogeomorphically, water will flow down the slope to the valley. It will reduce the infiltration rate. In general, the ridge area is only used for settlement, while the slopes are used for dryland agriculture. The geoelectric analysis results show that the groundwater potential is at a depth of more than 45 meters. This research’s results show that the combination of the hydrogeomorphological approach and the geoelectric use will provide a better description of the potential groundwater.

This publication, based on remote sensing data, examines the features of the effusive eruption of the Sarychev Peak volcano (Matua Isl., the Central Kuril Islands), which took place from December 2020 till February 2021. On the basis of the analysis of the Sentinel satellite data, it was established that starting from December 2020, the crater of the Sarychev Peak volcano began to fill with lava. As of January 18, 2021, it was completely filled, then lava outpouring through a fissure in the north-northwest part began. A lava flow (length 2 km, width 80–90 m) descended along the bottom of the valley, which cuts the northwestern slope of the volcanic cone. The outpouring of lava was completed by February 7, 2021. The effusive eruption of the Sarychev Peak volcano in 2020–2021 is atypical for the modern stage of eruptive history, characterized mainly by explosive and explosive-effusive type of eruptions.

The suspension flow from the upper part of a volcano watershed, which has a very thick soil condition, is sensitive to landuse form. Agroforestry is the dominant landuse form in the volcanic landscape of Indonesia. There is a lack of detailed studies about suspension flow in the upper watershed where agroforestry is the land cover. This research, performed in agroforestry area, covered the correspondence between flow discharge and suspension flow discharge, the time lag of initial rain events and the formation of suspension flow; and the characteristics of the grain size of the suspensions during the flow. The suspension flow was measured at the outlet of a gully in key watershed areas, which yielded a total of 436 suspension data. The measurement analysis was conducted at every rain event in the field and in the laboratory. The crop characteristics in the rain catchment area were recorded in details during the field survey. The characteristics of the channels converging toward the gully system were observed during the field survey. There were three relationship patterns between the peak flow discharge and the peak suspension discharge, namely (1) the peak flow discharge corresponded to the peak suspension discharge, (2) the peak flow discharge preceded the peak suspension discharge, (3) the peak flow discharge occurred after the peak suspension discharge. The average time interval between the rain events and the occurrence of suspension flow was 17.7 minutes. The peak suspension content varied from 0.0016 g/L up to 4.71 g/L with an average of 1.03 g/L. The grain size of the suspension was dominated by 71-76% of clay fraction with an average of 73% at the rising phase and 68-71% of clay fraction with an average of 69% at the falling stage.

• Paper 5 of Hawaii play fairway project: results of slim-hole drilling on Lanai. • Lanai temperature gradient of 42 °C/km, bottom hole temperature at ∼1 km of 66 °C. • Detailed analyses of Lanai drill core, including stratigraphic column. • Successful community outreach on Lanai. This paper builds on four earlier papers detailing the results of the Hawai'i Play Fairway (PF) project's first two phases. In Phase 3 the project deepened a water well on the rim of the caldera of Lāna'i Volcano to a maximum depth of just over 1 km. Due to funding constraints, the project deepened an already existing water well that was proximal to our area of highest resource probability within the caldera. Drilling preparation included: completion of an Environmental Assessment, lowering a camera down the well, deviation logging, coordinating site preparation, procure and shipping, and participating in multiple community meetings. Drilling occurred 24/7 the entire month of June 2019. The project deepened Lāna'i Well 10 from 427 m to 1057 m, while collecting continuous core, and measured a roughly linear temperature gradient averaging 42 °C/km and a maximum bottom hole temperature of 66 °C. This gradient is more than twice the background for Hawai'i and within a range of gradients measured in this depth range for some exploration wells within the volcanically active East Rift Zone of Kīlauea Volcano. Geothermal gradient determinations and computed chemical geothermometer temperatures indicate that accessible temperatures within Lāna'i Well 10 are 130–200 °C between 2 and 3 km depth. This paper includes a summary of detailed core logging, which found pervasive hydrothermal alteration. We recommend drilling a slim hole within Lāna'i's caldera to ∼2 km, where considerably higher temperatures may be encountered. The positive implications this project's results have for the island of O'ahu are substantial. The shield stage of O'ahu's volcanoes ended 1–2 Million years earlier, however O'ahu uses more electricity than the rest of the islands combined. [ABSTRACT FROM AUTHOR]

In February and March 2022, a large amount of pumice stone appeared along the shoreline of Thailand. Pumice is a type of extrusive volcanic rock, and since there are no volcanoes in the Gulf of Thailand, an interesting question was where the pumice stones originated from. Another question was whether the pumice could be a vehicle for microplastics (MPs) which could then journey across the ocean until reaching the coast of Thailand. A preliminary study was begun, which randomly collected samples from seven beaches in five provinces along the coast of Thailand. Grayish-green pumice stones are tiny, porous, and lightweight, ranging from 0.3 to 5.0 cm in size. The examination found 5.7–12.6 MP items per pumice stone. Most of the MP particles observed were less than 1 mm in length. From Fourier transform infrared spectroscopy (FTIR) analysis, the MPs were characterized as polystyrene, polypropylene, poly (ethylene terephthalate) (PET), rayon, and nylon. The MP could have entered the holes in pumice stones while floating on the water surface over long periods. From the seasonal flow patterns, it was revealed that pumice from the South China Sea was more likely to have floated with surface currents into the Gulf of Thailand

Summary: The network of lava tubes is one of the most unexploited natural wonders of the Galapagos Islands. Here, we provide the first morphological, mineralogical, and biogeochemical assessment of speleothems from volcanic caves of the Galapagos to understand their structure, composition, and origin, as well as to identify organic molecules preserved in speleothems. Mineralogical analyses revealed that moonmilk and coralloid speleothems from Bellavista and Royal Palm Caves were composed of calcite, opal-A, and minor amounts of clay minerals. Extracellular polymeric substances, fossilized bacteria, silica microspheres, and cell imprints on siliceous minerals evidenced microbe-mineral interactions and biologically-mediated silica precipitation. Alternating depositional layers between siliceous and carbonate minerals and the detection of biomarkers of surface vegetation and anthropogenic stressors indicated environmental and anthropogenic changes (agriculture, human waste, and cave visits) on these unique underground resources. Stable isotope analysis and Py-GC/MS were key to robustly identify biomarkers, allowing for implementation of future protection policies.

Sediments from the only permanent lake on the island of Jan Mayen (71°N, 08°30′W), Lake Nordlaguna (NL), were investigated. The lake, with an area of ∼1 km2, is situated at the foot of the world's northernmost active subaerial volcano and is separated from the sea by a 150–240 m wide beach barrier, which reaches 4–5 m above sea level. Most of the lake is deeper than 25 m, with the deepest part being 36 m. Altogether five coring sites, evenly spread out, were chosen and the sediment cores were retrieved from the lake ice with Uwitec and Nesje corers. After detailed descriptions of the very organic-poor and silt dominated sediments (of supposedly tephra-dominated origin), three sites were chosen for further analyses: macrofossils for 14C dating, tephra chemistry, C, S, grain-size, and XRF analyses. Based on 14C dates and the occurrence of the so-called Eggøya tephra (AD 1732), age models show variable bottom ages for the three sites: ∼3000, 600 and 400 cal yr BP. Due to the position of the core sites, with different sediment source areas, the elemental signals vary considerably between sites. An interesting feature of the lake is an isolated stock of Arctic char, which shows that the now land-locked lake has once been in contact with the sea. The almost total lack of organic material excluded any advanced paleo-ecologic investigations of the lake, and the study therefore focused on its marine-limnic history by different examinations of the XRF data with focus on the oldest and longest record. This development is based on elemental ratios (Br/Zn), PCA analyses of a center log ratio (clr) transformation of the original XRF data and magnetic susceptibility. It shows that the lake was isolated just before the time of the Eggøya tephra fall-out (∼220 cal yr BP), when the stock of Arctic char was most likely isolated from the sea. This was preceded by a ∼2200 yr long period of marine bay with a more or less open connection with the sea, and thus varying fresh-water impact. Between ∼2400 and 2600 cal yr BP the basin was more or less isolated, preceded by almost full marine conditions for at least the 300–400 preceding years we have data from, a period when relative sea level might have been higher.

The infrequent nature of volcanic eruptions means that civil authorities and the public may often be unfamiliar with volcanic hazards and may not be fully prepared to deal with them. Many times volcano scientists are required to help governments and citizens understand the threat posed to their lives and property when volcanoes show signs of an imminent eruption. Effectively communicating the potential impact of these events can demand time and skills that these scientists may or may not have. Further, a lack of trusted scientific information can lead to public misinformation and hamper government responses. Although several risk reduction researchers and observatory scientists have advocated for the inclusion of communication specialists in scientific teams, communication resources at many observatories remain under utilised. Using the experience of The University of the West Indies Seismic Research Centre (UWI-SRC), this article explores the contribution of a specialist communication team to the work of a volcano monitoring agency. The Education and Outreach (E&O) team at the UWI-SRC manages all the agency’s external communications. The team also works to raise public awareness of geological hazards in the UWI-SRC’s Eastern Caribbean region of responsibility. Within the Caribbean region, most communication research related to disaster risk up until now has focused on communication during crises. Using semi-structured interviews and document review we investigated the impact of strategic communication in a long-term, multi-hazard monitoring programme. A qualitative analysis highlighted the equal importance of crisis communication during unrest and outreach work during quiescent periods. The UWI-SRC’s communication programme has been effective in: 1) supporting scientists’ public communication 2) sustaining stakeholder engagement 3) building physical and social science capacity and 4) strengthening organisational credibility. This article examines the contribution of specialist communication to advisory volcano science throughout the disaster management cycle in the English-speaking Eastern Caribbean. It argues that significant societal value can be added to the scientific work engaged in by advisory scientists by embracing a multi-level communication strategy.

The description of the Unique Large-Scale Research Facilities "Seismic infrasound array for monitoring Arctic cryolithozone and continuous seismic monitoring of the Russian Federation, neighbouring territories and the world" (URF SIA MAC), its hardware and software components are presented. Methods and principle areas of research carried out using the URF are outlined. The URF SIA MAC includes 364 seismic stations throughout Russia and three infrasound arrays. The data obtained at the URF serve to provide domestic fundamental and applied research in the field of Earth Sciences (seismology, geophysics, geodynamics, geoecology) and to study catastrophic events of a natural induced nature. The modern URF data archive includes digital seismic records since 1993. In addition, there is a significant amount of analogue records (since 1904) available for further digitization. The URF SIA MAC provides seismological data to many Russian scientific, research and design organizations. The article presents the main results of the Federal Research Centre Geophysical Survey of the Russian Academy of Sciences obtained in recent years using the URF data.

Abstract Eastern Indonesia is one of the world’s most complex regions in terms of tsunami hazards, as it accommodates numerous seismic and non-seismic tsunami sources with a history of deadly tsunamis. This study is an effort to enhance tsunami hazard knowledge in eastern Indonesia where limited data and analyses exist. We provide a brief understanding of eastern Indonesia’s tsunami hazards by modelling selected deterministic tsunami scenarios from tectonic, submarine mass failure (SMF), and volcanic sources. To our knowledge, this is the first time that tsunami hazards modelling from such diverse sources in Indonesia has been performed. Our methodology is a deterministic tsunami hazard analysis considering credible tsunami sources from historical and contemporary data, modelling them using state-of-the-art simulation tools. We modelled two Mw7.8 tsunamigenic earthquake scenarios on the Flores back-arc thrust, one rupturing the basal fault (FBT-BF) and the other rupturing the splay fault (FBT-SF), showing that the two scenarios produce maximum tsunami amplitudes of $$\sim$$ ∼ 5.3 m and $$\sim$$ ∼ 4.2 m, respectively, which are comparable to the deadly 1992 Flores tsunami. We modelled potential SMF-generated tsunamis in the Makassar Strait with SMF volumes of 5 $$\hbox {km}^3$$ km 3 and 225 $$\hbox {km}^3$$ km 3 which yielded maximum tsunami heights of $$\sim$$ ∼ 1.1 m and $$\sim$$ ∼ 4.3 m along the eastern coast of Kalimantan Island and $$\sim$$ ∼ 2.9 m and $$\sim$$ ∼ 11.1 m along the west shore of Sulawesi Island, respectively. The 1871 Ruang volcanic tsunami is studied through existing historical documents and a source model is proposed comprising a flank collapse with volume of $$0.10\ \mathrm{km}^3$$ 0.10 km 3 . Such a source model successfully reproduced the 25 m runup reported in a historical account.

The tremendous development of Synthetic Aperture Radar (SAR) missions in recent years facilitates the study of smaller amplitude ground deformation over greater spatial scales using longer time series. However, this poses greater challenges for correcting atmospheric effects due to the wider coverage of SAR imagery than ever. Previous attempts have used observations from Global Positioning System (GPS) and Numerical Weather Models (NWMs) to separate atmospheric delays, but they are limited by ①The availability (and distribution) of GPS stations; ②The low spatial resolution of NWM; And ③The difficulties in quantifying their performance. To overcome these limitations, we have developed the Generic Atmospheric Correction Online Service for InSAR (GACOS) which utilizes the high-resolution European Centre for Medium-Range Weather Forecasts (ECMWF) products using an Iterative Tropospheric Decomposition (ITD) model. This enables the reduction of the coupling effects of the troposphere turbulence and stratification and hence achieves equivalent performances over flat and mountainous terrains. GACOS comprises a range of notable features: ①Global coverage; ②All-weather, all-time usability; ③Available with a maximum of two-day latency; And ④Indicators available to assess the model’s performance and feasibility. In this paper, we demonstrate some successful applications of the GACOS online service to a variety of geophysical studies.

The thermal conductivity of volcanic rock is an essential input parameter in a wide range of models designed to better understand volcanic and geothermal processes. However, although volcanoes and geothermal reservoirs are often characterised by temperatures above ambient, laboratory thermal conductivity measurements are often performed at ambient temperature. In addition, there are currently few data on the temperature dependence of thermal conductivity for andesite, a common volcanic rock. Here, we provide elevated-temperature (up to 120 °C) laboratory measurements of thermal conductivity for variably porous (∼0.05 to ∼0.6) and variably glassy andesites from Mt. Ruapheu (New Zealand) using the transient hot-strip method. Our data show that (1) the thermal conductivity of these andesites has little to no temperature dependence and, therefore, (2) there is also no influence of porosity on the temperature dependence of thermal conductivity. We compare our new data with compiled published data to show that the thermal conductivity of volcanic rocks may decrease, remain constant, or increase as a function of temperature. We show that the thermal conductivity of amorphous glass and crystalline material increase and decrease, respectively, as temperature increases. We therefore interpret the temperature dependence of the thermal conductivity of volcanic rock to be dependent on glass content. The thermal conductivity of the studied andesites, the microstructure of which can be characterised by phenocrysts within a variably glassy groundmass, has little to no temperature dependence because the decrease in the thermal conductivity of the crystalline materials, due to decreases in lattice thermal conductivity, is offset by the increase in the thermal conductivity of the amorphous glass. A simple modelling approach, using the temperature dependence of the thermal conductivity of glass and crystalline material, provides a crystal content of 0.26 for a thermal conductivity independent of temperature, a common crystal content for andesite dome rock. Our findings imply that calculations of heat transfer through partially glassy volcanic rocks need not consider a temperature-dependent thermal conductivity, but that decreases and increases in thermal conductivity with temperature should be expected for fully crystallised or devitrified volcanic rocks and completely glassy volcanic rocks, respectively. We highlight that more experimental studies are now required to assess the evolution of thermal conductivity as a function of temperature in a wide range of volcanic rocks with different crystallinities. • Thermal conductivity of porous andesites has little to no temperature dependence. • Temperature-dependence of thermal conductivity of volcanic rocks depends on glass content. • Modelling shows that crystal content of 0.26 is required for temperature-independent thermal conductivity. • Heat transfer calculations for partially glassy volcanic rocks need not use a temperature-dependent thermal conductivity. [ABSTRACT FROM AUTHOR]

We describe results from coastal radar systems that observed anomalous current flows generated by the volcanic eruption in the Tongan archipelago on 15 January 2022 UTC, reporting the first radar detection of a volcanic tsunami. The eruption caused small tsunamis along the western U.S. Coast, generating some damage in a few harbors. The highest tsunami signal in U.S. tide gauge data from the California coast occurred at Arena Cove, with significant heights detected at Port San Luis and Crescent City. We analyze correlated wave orbital velocity detections by High Frequency (HF) radars along the coast between Gerstle Cove and Santa Barbara. Signals observed by the radars indicate that the event had two phases, each with its own distinct genesis: an initial weak surface disturbance, most likely generated by the wave of atmospheric pressure that moved outward from the blast source at just below the speed of sound, followed by a stronger disturbance that arrived approximately 3.5 h later, matching the arrival time for a wave moving entirely through the water from the volcano to the U.S. West Coast. We conclude that this phase consists of a conventional water wave tsunami and weaker waves generated by the pulse. We also report the detection of a small pulse-generated event off the west coast of Florida. Radar observations are compared with water level measurements at nearby tide gauges and a DART buoy, and with observations of barometric pressure. We point out that a Proudman near-resonance at the Tonga Trench is unlikely to explain the second phase observations. Comparison with tide gauge signals at San Francisco, generated by the Krakatoa eruption in 1883, support our conclusions.

Nisyros Geopark, an island geopark in the Southeastern Aegean Sea, Greece, is here presented as an official candidate for the UNESCO Global Geoparks designation, featuring outstanding geological, natural and cultural characteristics tightly connected to its volcanic origin. It covers a total area of 481 km2 and includes Nisyros, an active volcano and the main island, the surrounding islets of Pachia, Strongyli, Pergousa, Kandeliousa and the marine region among them. It features 24 geosites and a network of well-established walking trails. Furthermore, there are two internationally designated Natura 2000 areas covering its entire surface and also exceptional archaeological and cultural sites, including fortresses, remnants of ancient habituations and numerous churches and monasteries. It is the only area in the broader region of the Eastern Mediterranean that hosts all these features within such a restricted area. The initial efforts of the management body of Nisyros Geopark and its scientific team to promote its unique geodiversity included the complete design, construction and launch of the official website, the mobile application “Nisyros Volcano App’’, a modern informative leaflet regarding the region of the hydrothermal craters (Lakki), a Geopark guidebook and a series of panels and signs for the geosites.

UAV-based photogrammetry is becoming increasingly popular even in application fields that, until recently, were deemed unsuitable for this technique. Depending on the characteristics of the investigated scenario, the generation of three-dimensional (3D) topographic models may in fact be affected by significant inaccuracies unless site-specific adaptations are implemented into the data collection and processing routines. In this paper, an ad hoc procedure to exploit high-resolution aerial photogrammetry for the multitemporal analysis of the unstable Sciara del Fuoco (SdF) slope at Stromboli Island (Italy) is presented. Use of the technique is inherently problematic because of the homogeneous aspect of the gray ash slope, which prevents a straightforward identification of match points in continuous frames. Moreover, due to site accessibility restrictions enforced by local authorities after the volcanic paroxysm in July 2019, Ground Control Points (GCPs) cannot be positioned to constrain georeferencing. Therefore, all 3D point clouds were georeferenced using GCPs acquired in a 2019 (pre-paroxysm) survey, together with stable Virtual Ground Control Points (VGCPs) belonging to a LiDAR survey carried out in 2012. Alignment refinement was then performed by means of an iterative algorithm based on the closest points. The procedure succeeded in correctly georeferencing six high-resolution point clouds acquired from April 2017 to July 2021, whose time-focused analysis made it possible to track several geomorphological structures associated with the continued volcanic activity. The procedure can be further extended to smaller-scale analyses such as the estimation of locally eroded/accumulated volumes and pave the way for rapid UAV-based georeferenced surveys in emergency conditions at the SdF. [ABSTRACT FROM AUTHOR]

The volcanic eruption of Cumbre Vieja (La Palma Island, Spain), started on 19 September 2021 and was declared terminated on 25 December 2021. A complete set of aerosol measurements were deployed around the volcano within the first month of the eruptive activity. This paper describes the results of the observations made at Tazacorte on the west bank of the island where a polarized micro-pulse lidar was deployed. The analyzed two-and-a-half months (16 October–31 December) reveal that the peak height of the lowermost and strongest volcanic plume did not exceed 3 km (the mean of the hourly values is 1.43 ± 0.45 km over the whole period) and was highly variable. The peak height of the lowermost volcanic plume steadily increased until week 11 after the eruption started (and 3 weeks before its end) and started decreasing afterward. The ash mass concentration was assessed with a method based on the polarization capability of the instrument. Two days with a high ash load were selected: The ash backscatter coefficient, aerosol optical depth, and the volume and particle depolarization ratios were, respectively, 3.6 (2.4) Mm−1sr−1, 0.52 (0.19), 0.13 (0.07) and 0.23 (0.13) on 18 October (15 November). Considering the limitation of current remote sensing techniques to detect large-to-giant particles, the ash mass concentration on the day with the highest ash load (18 October) was estimated to have peaked in the range of 800–3200 μg m−3 in the lowermost layer below 2.5 km. [ABSTRACT FROM AUTHOR]

Volcanoes are typical features of the solar system that offer a window into the interior of planets. Thus, their study can improve the understanding of the interiors and evolution of planets. On Earth, volcanoes are monitored by multiple sensors during their dormant and active phases. Presently, this is not feasible for other planets' volcanoes. However, robotic vehicles and the recent technological demonstration of Ingenuity on Mars open up the possibility of using the powerful and non-destructive geophysical tool of magnetic surveys at different heights, for the investigation of surfaces and subsurfaces. We propose a methodology with a view to extract information from planetary volcanoes in the short and medium term, which comprises an analysis of the morphology using images, magnetic field surveys at different heights, in situ measurements of magnetic susceptibility, and simplified models for the interpretation of geological structures. This methodology is applied successfully to the study of different examples of the main volcanic zones of the Iberian Peninsula, representative of the Martian intraplate volcanism and similar to Venus domes, as a preparatory action prior to the exploration of the rocky planets' surfaces. [ABSTRACT FROM AUTHOR]

In this study, sulphate efflorescent minerals covering the surface of the Donnoe and Dachnoe fields of the Mutnovsky volcano are described. The minerals were precipitated on the argillic facies as the result of water–rock interaction and fumarole emission. A chemical composition of Ca, Ba, (NH4)+, Na-Fe3+, (NH4)+-Al, (NH4)+-Fe3+, Na-Al, K-Al, and K-Fe3+ sulphates was reported. Elements such as Sr, Mg, Co, Ni, Ti and P were found as isomorphic impurities. Ammonia species were concentrated around fumaroles. The mineral assemblage described herein is unique in relation to other geological settings and reflects the process of low-temperature mineral formation associated with volcanism. The thermal water contains cations such as H, Na, K, NH4, Ca, Mg, Fe2+, Fe3+, and Al in different proportions with pH ranging from 2.4 to 6.5 and the dominance of acidic waters. The gas condensate bears such cations as (NH4)+, Ca, and Mg and has a pH of ~5. Thus, the rest of the main cations are derived from the leaching of the host rocks. Among the identified phases, the alunite-supergroup minerals are more prone to isomorphism. The Ti, Co, and Ni impurities mark the unique geochemistry of thermal water at the Mutnovsky volcano. We postulate that the chemical composition of alunite-supergroup minerals reflects the types of hydrothermal occurrences and contains important information on the geochemistry of the hydrothermal process. [ABSTRACT FROM AUTHOR]

Glaciers constitute a polyextremophilic environment characterized by low temperatures, high solar radiation, a lack of nutrients, and low water availability. However, glaciers located in volcanic regions have special characteristics, since the volcanic foci provide them with heat and nutrients that allow the growth of microbial communities highly adapted to this environment. Most of the studies on these glacial ecosystems have been carried out in volcanic environments in the northern hemisphere, including Iceland and the Pacific Northwest. To better know, the microbial diversity of the underexplored glacial ecosystems and to check what their specific characteristics were, we studied the structure of bacterial communities living in volcanic glaciers in Deception Island, Antarctica, and in the Kamchatka peninsula. In addition to geographic coordinates, many other glacier environmental factors (like volcanic activity, altitude, temperature, pH, or ice chemical composition) that can influence the diversity and distribution of microbial communities were considered in this study. Finally, using their taxonomic assignments, an attempt was made to compare how different or similar are the biogeochemical cycles in which these microbiomes are involved. [ABSTRACT FROM AUTHOR]

Recent seismic and geodetic observations suggest the involvement of pressurized fluid and aseismic slip during earthquake swarms. However, the interaction between these two factors is not fully understood. In this study, we show geodetic signals induced by aseismic opening and shear dislocation on a fault, accompanied by hypocenter migration during an earthquake swarm in the Hakone volcano, central Japan. The hypocenters were concentrated on a vertical plane, and the focal mechanisms were strike‐slip faults whose nodal planes were consistent with the hypocenter distribution. Precursory seismicity occurred 1 week before the main swarm. We observed a complex pattern of hypocenter migration during the seismic sequence; namely, the lower limit of the seismicity appears to expand downward during the precursory seismicity, followed by an upward hypocenter diffusion. We also observed tilt changes that could be explained by opening and shear dislocation on the fault plane inferred from the planar hypocenter distribution. Furthermore, we identified several groups of repeating earthquakes. The average aseismic slip history inferred from the repeating earthquakes indicated a minor aseismic slip of 0.4 mm during the precursory seismic activity, which accelerated by up to 3 mm during the main swarm. The total cumulative slip was consistent with the geodetic model results. These observations may suggest that fluid intrusion caused the aseismic slip, and the complex migration of the hypocenters reflects the aseismic slip propagation. We hypothesize that aseismic deformation acts as the driving force for the earthquake swarms together with the intrusion of pressurized fluid. Plain Language Summary: An earthquake swarm is seismic activity that deviates from the typical mainshock–aftershock sequence. According to several studies, the triggering of earthquake swarms is related to the migration of highly pressurized fluid. However, aseismic slip on a fault plane is also thought to drive the triggering of earthquake swarms. Based on precise hypocenter locations, a combination of both the driving forces was suggested to be responsible for the occurrence and hypocenter migration of earthquake swarms. However, the interaction between aseismic deformation and fluid injection in earthquake swarms has not been fully clarified. From 11 May to 20 May 2019, an earthquake swarm occurred beneath Lake Ashi in the western part of the Hakone caldera, Japan. In this study, we analyzed geodetic data obtained using tiltmeters and observations of repeating earthquakes and investigated the aseismic deformation associated with the swarm activity. We detected a significant tilt change that was consistent with shear tensile fault movements. We also detected several groups of repeating earthquakes and the migration of hypocenters. The findings suggest that aseismic deformation acts as the driving force for earthquake swarms in addition to the intrusion of highly pressurized fluid. Key Points: A complex hypocenter migration pattern was observed during the earthquake swarmThe complex hypocenter migration, repeating earthquakes, and tilt changes may suggest the occurrence of aseismic slip [ABSTRACT FROM AUTHOR]

Copyright of Journal of Geodesy & Geodynamics (1671-5942) is the property of Editorial Board Journal of Geodesy & Geodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Paleomagnetic and rock magnetic methods for studying volcanoes and their products have been developed since the second half of the twentieth century. These methods have been used to find tephra in sediment cores, date volcanic eruptions and deposits, determine emplacement temperatures of volcanic deposits, and estimate flow directions of dikes, lava flows, and pyroclastic flow deposits. In the twenty-first century, these techniques have steadily improved and expanded, resulting in more probing and precise studies of volcanoes using paleomagnetism. We believe that continual improvement of existing techniques and the increased awareness and interest in paleomagnetic methods should allow more studies to enhance the understanding of volcanic processes. [ABSTRACT FROM AUTHOR]

The Euganean Hills (NE Italy) magmatic district represents the final volcanic activity of the Veneto Volcanic Province. Alkaline to subalkaline magmatic suite dominated by intermediate to felsic volcanic rocks characterises the latest volcanic activity of the Euganean Hills. Magmatic (intrusive and volcanic) enclaves are common in Euganean Hills trachytes. We used the ability of clinopyroxene to record variations of P, T, and fO 2 to reconstruct the geological history of the volcanic enclaves and trachytic host. Despite similar major and trace elements composition, clinopyroxene from host is higher in Ca and Na (and Fe 3 + ) and lower in Mg than enclaves and is slightly enriched in trace elements but with the same pattern distribution. Minor differences in geochemistry and crystal structure of clinopyroxene from enclaves and trachytic host suggest similar parental magmas that differs by small degrees of fractional crystallisation. Clinopyroxene geobarometry performed combining X-ray diffraction with mineral geochemistry for volcanic enclaves–trachytic host combined with amphibole geobarometry for intrusive enclaves and crystal mushes points to a crystallisation pressure range between 4.8–2.0 kbars. Our data support the model of a complex system of magma chambers at intermediate to shallow crustal level where mafic magma accumulated, evolved by fractionation processes and mixed. [ABSTRACT FROM AUTHOR]

This article proposes a supervised tensor-based learning framework for classifying volcano-seismic events from signals recorded at the Ubinas volcano, in Peru, during a period of great activity in 2009. The proposed method is fully tensorial, as it integrates the three main steps of the automatic classification system (feature extraction, dimensionality reduction, and classifier) in a general multidimensional framework for tensor data, joining tensor learning techniques such as the multilinear principal component analysis (MPCA) and the support tensor machine (STM). By exploiting the use of multiple multichannel triaxial sensors, operating simultaneously in two seismic stations, the tensor patterns are constructed as stations × channels × features. The multidimensional structure of the data is then preserved, avoiding the tensor vectorization that often leads to a feature vector with a large dimension, which increases the number of parameters and may cause the “curse of dimensionality.”Moreover, the array vectorization breaks down the multidimensional structure of the data, which usually leads to performance degradation. The results showed a good performance of the proposed multilinear classification system, significantly outperforming its vectorial counterparts. The best result was obtained with the STuM classifier along with the MPCA.

With the growing ability to collect large volumes of volcano seismic data, the detection and labeling process of these records is increasingly challenging. Clearly, analyzing all available data through manual inspection is no longer a viable option. Supervised machine learning models might be considered to automatize the analysis of data acquired by in situ monitoring stations. However, the direct application of such algorithms is defiant, given the high complexity of waveforms and the scarce and often imbalanced amount of labeled data. In light of this and motivated by the wide success that generative adversarial networks (GANs) have seen at generating images, we present ESeismic-GAN, a GAN model to generate the magnitude frequency response of volcanic events. Our experiments demonstrate that ESeismic-GAN learns to generate the frequency components that characterize long-period and volcano-tectonic events from Cotopaxi volcano. We evaluate the performance of ESeismic-GAN during the training stage using Fréchet distance, and, later on, we reconstruct the signals into time-domain to be finally evaluated with Frechet inception distance.

This report provides a brief description of the field work on the Kuril Islands. It was performed within the framework of the R&D theme, projects of the RSF and the RFFR, which are realized in the laboratory of postmagmatic processes of the Institute of Volcanology and Seismology FEB RAS. Hydrological and hydrochemical works were performed on the rivers draining the slopes and thermal fields of the Sinarka, Kuntomintar volcanic massifs (Shiashkotan Island), and the Vernadsky and Karpinsky Ridges (Paramushir Island). The study of the chemical erosion of volcanic islands and the assessment of the hydrothermal export of magmatic volatiles are the goals of this work. Infrared photography was taken and the total flux of volcanic SO2 and diffusion flux of CO2 were measured on thermal fields in the caldera of Golovnin volcano. A detailed hydrogeochemical survey was made on the thermal fields of the Ebeko volcano to study the relationship of volcanic and hydrothermal activity of the volcano. For further analytical work, a large number of water and gas samples were taken and a representative collection of rocks and sediments was collected during the expedition.

The work presents modern data on the location, morphometry, and genesis of the largest lakes basins of the Kuril Islands obtained in the volcanological expeditions of the IMGG FEB RAS during 2005– 2018 and using open geographic information resources. 1099 lakes were sampled according to the criterion S≥1 km², the list of studied objects included 20 reservoirs, represented by 7 volcanic and 13 lagoon lakes. The considered lakes are clearly divided according to their origin, area and height of the mirror, and maximum depth. The most part of large lakes falls on the Southern Kurils, and the largest water body – the volcanic lake Koltsevoe – is located on Onekotan Island, which is a part of the group of the Northern Kurils. Volcanic lakes occupy an area of 48.26 km² (60% of the total area of 20 lakes), the depth varies in the range from several tens to several hundred meters. This category of lakes is characterized by relatively high levels of the mirror, which range from 50 to 648 m above sea level. Lagoon lakes occupy an area of 32.15km² (40% of the total area of 20 lakes), the depth of water bodies is small – from 1 to 23 m, the absolute height of the lake mirror is from 1–5 to 8–9 m.

Glaciers constitute a polyextremophilic environment characterized by low temperatures, high solar radiation, a lack of nutrients, and low water availability. However, glaciers located in volcanic regions have special characteristics, since the volcanic foci provide them with heat and nutrients that allow the growth of microbial communities highly adapted to this environment. Most of the studies on these glacial ecosystems have been carried out in volcanic environments in the northern hemisphere, including Iceland and the Pacific Northwest. To better know, the microbial diversity of the underexplored glacial ecosystems and to check what their specific characteristics were, we studied the structure of bacterial communities living in volcanic glaciers in Deception Island, Antarctica, and in the Kamchatka peninsula. In addition to geographic coordinates, many other glacier environmental factors (like volcanic activity, altitude, temperature, pH, or ice chemical composition) that can influence the diversity and distribution of microbial communities were considered in this study. Finally, using their taxonomic assignments, an attempt was made to compare how different or similar are the biogeochemical cycles in which these microbiomes are involved.

Monitoring the activity of subglacial volcanoes along the Aleutian Arc in Alaska is important to the safety of local populations, as well as air traffic flying through the region. However, observations of volcanic unrest are limited by accessibility and resources, particularly at glacier-covered systems, making investigations of their stability challenging. Westdahl Peak, a subglacial volcano on Unimak Island in the Aleutian Arc has experienced significant unrest and uplift since its most recent VEI three eruption in 1991-1992. Given the magnitude of observed uplift, previous investigations suggested the potential for eruption by 2010, but no such event has occurred. One hypothesis to explain this prolonged unrest is that the 1-km thick glacier may increase the stability of the magma system. However, the impact of ice caps and glaciers on the short-term stability of volcanoes is not well understood. In this study, thermomechanical finite element models are used to evaluate how the stability of a glaciated volcano is impacted by variations in ice cap thickness, magma chamber depth, geometry, magma flux rate, and seasonal changes in ice cover thickness. Our numerical experiments indicate that the presence of an ice cap (1–3 km thick) increases the average repose interval for a magma system. Among models with different magma chamber geometries, depths, and flux rates, the greatest increases in repose interval are observed in prolate systems where the increase is up to 57% for a chamber located at 5 km-depth. Spherical and oblate also experience smaller, yet significant, increases in repose interval. Additionally, the percentage increase in repose interval is not impacted by variations in magma flux rate for a given ice cap thickness and magma chamber geometry. However, flux rates do influence the timing of eruptions when the system is experiencing seasonal variations in ice thickness. Our results show that systems with low flux rates are more likely to fail when the ice thickness is at its lowest. The numerical estimates further suggest that the ice cap on Westdahl Peak, which is ∼1 km, may slightly increase the stability of the magma system. In general, given flux rates and magma chamber geometries estimated for the Westdahl system, the repose interval can increase by ∼7 years due to the Westdahl glacier. This increase is small on a geologic scale but is significant on human time scales and the impact of glaciers must be considered in future forecasting efforts.

Hazard assessment of remote volcanic islands provides many challenges compared to other volcanoes and volcanic fields. Here we present the first systematic volcanic hazard assessment of Jan Mayen Island, a remote island located in the North-Atlantic Ocean and home to the northernmost active subaerial volcano in the world (Beerenberg Volcano), and we discuss some of the challenges and characteristics of performing a volcanic hazard assessment of a remote volcanic island. Jan Mayen has had at least five eruptions since its discovery at the start of the 17th century. Its Holocene volcanism is mainly characterized by eruptions with styles ranging from Hawaiian to Strombolian, but also by lava domes and Surtseyan eruptions. Based on field data, remote images, topographic data, past data, and computer simulations, our study evaluates the spatial probability of new vents opening, estimates eruption recurrence rates, simulates various eruption scenarios, and produces hazard maps for the different scenarios. This work shows where the hazards of ash fall, and lava flows are more likely to affect the built infrastructure on Jan Mayen Island. This hazard assessment will assist emergency planning and the determination of future land use on the island.

Our study is a pioneering exploration of the microbiome in the soil of the Sumaco stratovolcano and an assessment of the effects of an elevational gradient and related physicochemical soil parameters on richness and community structure. The Sumaco, as an isolated Amazonian stratovolcano, may be among one of the least studied ecosystems in Ecuador and perhaps the Amazon region. Universal patterns remain unresolved or available information inconclusive to establish a supported consensus on general governing processes by which elevation and its associated environmental gradients may determine the microbial richness and community structure. We tested a recent proposal on how microbial diversity responds to montane gradients, placing a central role in soils as potentially independent of altitude along an elevational gradient. Correlations and effects among soil physicochemical parameters and altitude were contrasted against richness and community structure through quantitative ecology. The most informative physicochemical parameter in our assessment of bacterial community structure was neither pH nor altitude, but sulfur, which was mostly independent of the other tested parameters. We established a positive effect of richness by parameters associated with metallic cations such as Mn2+, and CEC, which were negatively correlated to altitude and pH. The possible relation between the significant role of sulfur on bacterial community structure with the unique geological origin of the Sumaco stratovolcano should be examined in the context of specialized sulfur metabolisms and additional information on community structure and environmental constraints. Our study establishes an initial baseline for further explorations of microbial diversity in this unexplored tropical stratovolcano.

Volcanic flood basalt eruptions have been linked to or are contemporaneous with major climate disruptions, ocean anoxic events, and mass extinctions throughout at least the last 400 M years of Earth's history. Previous studies and recent history have shown that volcanically‐driven climate cooling can occur through reflection of sunlight by H2SO4 aerosols, while longer‐term climate warming can occur via CO2 emissions. We use the Goddard Earth Observing System Chemistry‐Climate Model to simulate a 4‐year duration volcanic SO2 emission of the scale of the Wapshilla Ridge member of the Columbia River Basalt eruption. Brief cooling from H2SO4 aerosols is outweighed by dynamically and radiatively driven warming of the climate through a three orders of magnitude increase in stratospheric H2O vapor. Plain Language Summary: Volcanic flood basalt eruptions are linked to mass extinctions and climate change through Earth's history. Using model experiments, we show that a massive release of sulfur dioxide gas, as would happen in such an eruption, can warm the climate through feedback mechanisms linked to an increase in stratospheric water vapor. Key Points: Volcanic emission of SO2 produces warming through climate feedbacksThe warming is driven by a three orders of magnitude increase in stratospheric H2O vaporClimate cooling by H2SO4 aerosols persists for less time than the eruption itself [ABSTRACT FROM AUTHOR]

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Understanding the extensional processes in tectonic context at the transition from continental to oceanic spreading is fundamental to obtain new insights about formations of new oceans. To that scope, we study a large and long‐lived earthquake swarm occurring in 2020–2021 in a back‐arc rift (the Bransfield Basin) south of the South Shetland Islands, Antarctica. We make use of one local seismological station to detect more than 36,000 small earthquakes, occurring from August 2020 to June 2021. Together with the occurrence of earthquakes, we observe a significant, geodetic deformation at a nearby GPS station. By joint interpretation of b‐value, spatiotemporal evolution of seismicity and geodetic deformation, we infer a volcanic origin for this swarm that takes place close to the ridge axis. Our study suggests that beyond the 7 mm/yr deformation reported at the Bransfield Basin ridge, transient deformation episodes localized at the ridge axial volcanic structure also modulate the extension. Plain Language Summary: Understanding the extensional tectonics in places at the transition from continental to oceanic spreading, can provide new insights about the extensional processes leading to formation of new oceans. We report on a long‐lived (∼1 year) earthquake swarm in the Bransfield Basin, just south of the South Shetland islands, in Antarctica, that brings new observations to such tectonics. This basin represents a ridge separating two tectonic plates and is characterized by extensional tectonics at the transition from back‐arc rifting to ocean spreading. By detection and characterization of more than 36,000 earthquakes and observation of associated geodetic deformation, we inferred the significant role played by volcanic processes occurring at the ridge axis, in modulating extension of the basin. This observation differs from models of purely tectonic extensional processes involving rift bounding border faults. Key Points: We characterized one of the largest swarms ever recorded in a spreading ridgeAnalysis of seismological and geodetic data suggest volcanic origin for this swarmWe infer a significant role played by axial volcanic structures in opening of spreading ridges [ABSTRACT FROM AUTHOR]

Community resilience is a novel construct that allows us to recognize the active role that communities play when facing adversity or collective affectation. That is why this research article aims to analyze the role of community resilience in the face of disasters in a group of inhabitants of the Mapachico community in the center of the city of Pasto. The research was developed from the qualitative paradigm, the phenomenological approach and the type of ethnomethodological study. The results show that the components of collective self-esteem, cultural identity and solidarity favor the reconstruction of the social fabric and shape perceptions of risk, while social humor is emerging as an opportunity to generate community resistance processes. As a conclusion, it can be said that community resilience is expressed as a characteristic that allows the integration and identification of members in social development issues. [ABSTRACT FROM AUTHOR]

Copyright of Synergies Portugal is the property of GERFLINT (Groupe d'Etudes et de Recherches pour le Francais Langue Internationale) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ground deformation measured from interferometric synthetic aperture radar (InSAR) data is considered a sign of volcanic unrest, statistically linked to a volcanic eruption. Recent studies have shown the potential of using Sentinel-1 InSAR data and supervised deep learning (DL) methods for the detection of volcanic deformation signals, toward global volcanic hazard mitigation. However, detection accuracy is compromised from the lack of labeled data and class imbalance. To overcome this, synthetic data are typically used for fine-tuning DL models pretrained on the ImageNet dataset. This approach suffers from poor generalization on real InSAR data. This letter proposes the use of self-supervised contrastive learning to learn quality visual representations hidden in unlabeled InSAR data. Our approach, based on the SimCLR framework, provides a solution that does not require a specialized architecture nor a large labeled or synthetic dataset. We show that our self-supervised pipeline achieves higher accuracy with respect to the state-of-the-art methods and shows excellent generalization even for out-of-distribution test data. Finally, we showcase the effectiveness of our approach for detecting the unrest episodes preceding the recent Icelandic Fagradalsfjall volcanic eruption. [ABSTRACT FROM AUTHOR]