GMPV9.5 | Multidisciplinary volcano observations and models: from near-surface activity to deep magma migration
Multidisciplinary volcano observations and models: from near-surface activity to deep magma migration
Convener: Gaetana Ganci | Co-conveners: Jurgen Neuberg, Eva EiblECSECS, Miriam Christina Reiss, Dario Pedrazzi, Iestyn Barr, Annalisa CappelloECSECS
| Tue, 16 Apr, 14:00–15:40 (CEST), 16:15–17:55 (CEST)
Room D2
Posters on site
| Attendance Mon, 15 Apr, 10:45–12:30 (CEST) | Display Mon, 15 Apr, 08:30–12:30
Hall X1
Orals |
Tue, 14:00
Mon, 10:45
Volcanoes cause high-risk phenomena, such as pyroclastic and lava flows, lahars and glacial outburst floods from sub-glacial environments, as well as far reaching ash dispersal. A broad range of both ground- and satellite-based instrumentation capture geophysical responses, geological features and geochemical emissions, permitting an unprecedented, multi-parameter vision of the surface manifestations of magmatic processes beneath volcanoes.
Developing physical-mathematical models able to interpret the observed signals and describe the evolution of eruptive phenomena is a key point in volcanology. Predicting their spatial and temporal evolution and determining the potentially affected areas is fundamental in supporting every action directed at mitigating the risk as well as for environmental planning.
Within this context, this session aims to bring together a multidisciplinary audience to discuss the most recent innovations in volcano imaging and monitoring, and to present observations, methods and models that increase our understanding of volcanic processes.

Orals: Tue, 16 Apr | Room D2

Chairpersons: Gaetana Ganci, Annalisa Cappello, Eva Eibl
On-site presentation
Arnau Folch

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 dispersal and short-range fallout telescopically. This will be integrated in the EPOS Volcanic Observations TCS (VO-TCS). All these initiatives liaise, align, and synergise with EPOS and longer-term mission-like initiatives like Destination Earth.

How to cite: Folch, A.: Workflows for volcano hazard assessment in cloud and HPC research infrastructures, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6365,, 2024.

On-site presentation
Helen Dacre, Natalie Harvey, and Lauren James

Generating accurate quantitative volcanic ash forecasts poses a considerable challenge, especially in remote volcanic locations where there are large uncertainties regarding the timing, quantity, and vertical distribution of ash released. Quantifying this uncertainty is crucial for providing timely and reliable volcanic hazard warnings. Our research presents methodologies aimed at quantifying the uncertainty associated with volcanic ash dispersion forecasts.  Ensemble forecasting techniques that account for input, parametric, and structural uncertainties result in volcanic ash forecasts with low confidence, making them challenging for decision-making. To enhance the utility of these forecasts, we introduce data assimilation methods that combine ensemble volcanic ash predictions with satellite retrievals, considering uncertainties from both data sources. This approach enables us to constrain emission estimates, subsequently increasing confidence in the forecasts. By applying a risk-based methodology to these refined dispersion simulations, we significantly reduce the high-risk areas, minimizing disruptions to flight operations. These findings offer insights for the design of ensemble methodologies, facilitating the transition from deterministic to probabilistic volcanic ash forecasting. 

How to cite: Dacre, H., Harvey, N., and James, L.: Enhancing Confidence in Volcanic Ash Forecasts: Approaches for Quantifying and Reducing Uncertainties, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10127,, 2024.

On-site presentation
Francesco Zuccarello, Giuseppe Bilotta, Flavio Cannavò, Annalisa Cappello, Roberto Guardo, and Gaetana Ganci

Lava flows represent the main hazardous phenomena that may threaten human buildings in basaltic volcanoes. Physical and chemical characteristics of lava, as well as the rate at which lava is emitted at the vents, strongly control the motion and the extensions of lava flows. Estimation of the likely paths that lava flows may follow during an ongoing eruption can be evaluated through numerical modeling driven by satellite-derived time averaged discharge rate (TADR). However, complex eruptive dynamics, such as the sequential opening of new vents, formation of lava tubes and fluctuations in effusion rates, may lead to the development of composite lava fields, which are challenging to reproduce with a simple 2D modeling. In this study, we present a new optimization algorithm based on the Metropolis-Hastings approach to model complex emplacements of lava flow fields using satellite imagery. In particular, the algorithm performs sequential time-step refinements by assimilating TADR estimations, derived from low spatial resolution satellite imagery (e.g. MODIS, SLSTR, SEVIRI), and the locations of both main and ephemeral vents, obtained from higher spatial resolution imagery (e.g. MSI Sentinel 2, OLI & TIRS Landsat 8/9 or Planetscope). The algorithm automatically chooses the optimal input parameters and the associated uncertainty, minimizing the mismatch between the simulated and the observed lava flow features extracted from multi-source satellite imagery. The testing and validation have been performed using two recent effusive events that occurred at Mt. Etna (Italy): the 27 February - 1 March 2017 and the 27 November 2022 - 6 February 2023 eruptions.

How to cite: Zuccarello, F., Bilotta, G., Cannavò, F., Cappello, A., Guardo, R., and Ganci, G.: A new algorithm for complex lava flow modeling driven by satellite-derived data, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8471,, 2024.

On-site presentation
Sophie Pearson-Grant, Jonas Köpping, James Patterson, and Thomas Driesner

Phreatic or steam-driven eruptions are the most common type of volcanic eruption in New Zealand. They are notoriously difficult to forecast and have caused fatalities globally. There are two main conceptual models that have been proposed to lead to phreatic eruptions: a) cracking of a hydrothermal seal that is trapping pressurised fluid, and/or b) an injection of hot magmatic gas interacting with cold groundwater that then flashes to steam resulting in rapid fluid overpressure and overburden failure. Testing these hypotheses can help to determine the subsurface processes and timescales leading to an eruption, a possible key to unlocking phreatic eruption forecasting.

We have created generalised 2D numerical models of heat and fluid flow based on conceptual models of Whakaari/White Island volcano in New Zealand. Using CSMP++, we have explored the conditions that allow a build-up of fluids with sufficient overpressure to cause rock failure and potentially initiate an eruption. Our models simulate a sealed hydrothermal system above a magma reservoir. In some models, there is a high permeability zone linking the two which represents a highly fractured zone inferred from fumarole and degassing locations at Whakaari. A subset of these models also includes low permeability zones on either side of the highly fractured zone, which correspond to inferred regions of hydrothermal alteration.

Model results suggest that the permeability of the rock affects how quickly fluids move, but not the long-term pressure distribution. Our models show pressure increases of more than 5 MPa beneath the hydrothermal seal purely due to magmatic heating of groundwater. However, the timescales are on the order of decades. If low-permeability alteration zones are included which limit lateral flow of fluids, pressure increases by 5 MPa from hydrostatic in less than two years. We are now exploring the effects of adding magmatic fluids as well as heat, and will compare results of these models with field and experimental observations from Whakaari volcano.

How to cite: Pearson-Grant, S., Köpping, J., Patterson, J., and Driesner, T.: Modelling the conditions that may lead to phreatic eruptions, with comparison to Whakaari volcano, New Zealand, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6999,, 2024.

On-site presentation
Roberto Guardo, Giuseppe Bilotta, Gaetana Ganci, Francesco Zuccarello, Daniele Andronico, and Annalisa Cappello

Numerical models have been extensively explored for simulating forest fire propagation, employing a spectrum of approaches ranging from intricate physical models to simpler graph or cellular automata-based models. These models rely on various input parameters such as humidity, radiant capacity, vegetation flammability, tree types, wind and topography to accurately replicate fire spread. When integrated with Geographic Information Systems (GIS), these models facilitate classifying soil and mapping burnt areas. Despite the progress in forest fire models, a dedicated model for volcanic-induced fires is notably absent. Leveraging our expertise in lava flow hazard modeling, we have introduced a novel numerical model to address the current lack of a specific model for volcanic-induced fires. This model is based on cellular automata to tackle issues related to accessibility, usability, and computational costs inherent in existing applications. Indeed, the increased availability of low-cost, high-performance computing hardware has enhanced the accessibility and cost-effectiveness of cellular automata-based simulations, enabling the simulation of fire propagation under multiple environmental conditions. Our new model is able to generate fire hazard scenarios, providing insights into the likelihood of combustion. We present test cases using Stromboli Island as a case study, as it is an area where volcanic eruptions already caused fires that also contributed to human loss. Our results exhibit good spatial accuracy, with a Brier score of 0.188±0.002 and 0.073±0.001 for the fire spread on July 3, 2019, and May 25, 2022, respectively.

How to cite: Guardo, R., Bilotta, G., Ganci, G., Zuccarello, F., Andronico, D., and Cappello, A.: Volcanic fire hazard modeling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6412,, 2024.

On-site presentation
Valerio Acocella, Maurizio Ripepe, Eleonora Rivalta, Aline Peltier, Federico Galetto, and Erouscilla Joseph

Forecasting eruptions is a fundamental goal of volcanology. However,
difficulties in identifying eruptive precursors, fragmented approaches
and lack of resources make eruption forecasting difficult to achieve.
In this Review, we explore the first-order scientific approaches that
are essential to progress towards forecasting the time and location of
magmatic eruptions. Forecasting in time uses different monitoring
techniques, depending on the conduit-opening mode. Ascending
magma can create a new conduit (closed-conduit eruptions), use
a previously open conduit (open-conduit eruptions) or flow below a
solidified magma plug (semi-open-conduit eruptions). Closed-conduit
eruptions provide stronger monitoring signals often detected months
in advance, but they commonly occur at volcanoes with poorly
known pre-eruptive behaviour. Open-conduit eruptions, associated
with low-viscosity magmas, provide more subtle signals often
detected only minutes in advance, although their higher eruption
frequency promotes more testable approaches. Semi-open-conduit
eruptions show intermediate behaviours, potentially displaying clear
pre-eruptive signals days in advance and often recurring repeatedly.
However, any given volcano can experience multiple conduit-opening
modes, sometimes simultaneously, requiring combinations of
forecasting approaches. Forecasting the location of vent opening
relies on determining the stresses controlling magma propagation,
deformation and seismic monitoring. The use of physics-based models
to assimilate monitoring data and observations will substantially
improve forecasting, but requires a deeper understanding of
pre-eruptive processes and more extensive monitoring data.


How to cite: Acocella, V., Ripepe, M., Rivalta, E., Peltier, A., Galetto, F., and Joseph, E.: Towards scientific forecasting of magmatic eruptions, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4441,, 2024.

On-site presentation
Alessandro Bonaccorso, Luigi Carleo, Gilda Currenti, and Antonino Sicali

In recent decades, Etna's main eruptive activity  was characterized by prolonged sequences of lava fountain episodes. In particular, the sequence from December 2020 to February 2022 was characterized by 65 lava fountains. After the conclusion of the last sequence in February 2022, preceded a few days earlier by a shallow seismic swarm, a powerful fountain occurred on May 21, 2023. This lava fountain was unexpected since it was far from the previous sequence and did not even  belong to a new sequence. The greatest criticality was the difficulty in monitoring this eruptive event using conventional remote sensing devices due to the bad weather conditions characterized by thick cloud cover.

In this study we present the strain data recorded by the borehole dilatometers network on Etna. The high precision strain changes make it possible to follow all the recent lava fountains providing a valuable interpretative contribution. Through new approaches recently implemented, the analysis of the strain data allowed us to identify the correct timing of the events, evaluate the ‘size’ of the fountain (i.e. its eruptive power) and estimate the erupted volumes in near real-time. In particular, during the 21 May 2023 event, the quantification of these features provided a useful support during the Civil Protection meeting convened in emergency at the Prefecture of Catania, where the evolution of these features was presented and updated in near real-time. The experience gained on the 21 May 2023 lava fountain demonstrates the contribution that the real-time high precision strain may provide to define and evaluate the hazard associated with a lava fountain even in unfavorable weather conditions, when the remote sensing systems may not be able to provide helpful information on the ongoing phenomenon.

How to cite: Bonaccorso, A., Carleo, L., Currenti, G., and Sicali, A.: Lava fountains at Etna volcano deciphered in real-time by high precisions borehole strainmeters data and implications on hazard mitigation: the 21 May 2023 case, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8437,, 2024.

Virtual presentation
Vincent Drouin, Benedikt Gunnar Ófeigsson, Halldór Geirsson, and Sigrún Hreinsdóttir

Volcanic activity can take several forms ; one of them is magma moving horizontally along the crust and forming a dike, i.e. subvertical magma-filled structures. Dikes pose substantial risk to population and infrastructure at the surface. They can transport the magma far away from the main volcanic edifice and result in eruptions in unexpected locations. The larger dikes will also induce surface faulting and even the formation of grabens. However, this means that we can measure this deformation at the surface to infer characteristics of the dike. This is traditionally done after the dike as finished propagating by using a combination of GNSS and InSAR measurements.

In Iceland, there have been 6 dikes intrusion on the Reykjanes Peninsula since 2021. The first four dikes occurred in uninhabited areas, originating from the Fagradalsfjall volcanic system. The last two dikes, in November and December 2023, originated from the Svartsengi volcano and are along an axis that goes partly under the town of Grindavik. All these dike intrusions have been recorded by the local continuous GNSS network. We tested the applicability of near real-time tracking of the dike propagation for all of these events. This is done by searching for the best-fitting Okada dislocation that explains the GNSS displacements, with some assumption about the origin and direction of the magma. The earlier events cannot be easily tracked because the GNSS network was too sparse. However, the network has been densified with time and the later events are easier to track. For the largest one, in Nov. 2023, we are able to observe the initial vertical propagation of the magma, its horizontal propagation to the SW and the NE, and its focus to SW at the end. We can measure the magma inflow rate within the dike hour by hour through the event. It peaks at over 9000 m3/s two hours after the beginning of the event. These results show that, given a network of a few continuous GNSS stations, it is possible to have a near real-time monitoring of a dike. Having this information would be extremely valuable to the decision takers and the civil protection. Therefore, it is planned to have this tool implemented at the Icelandic Met Office in the coming weeks to be able track future events. It will be set up for specific volcanoes and run automatically based on real-time GNSS solutions.

How to cite: Drouin, V., Ófeigsson, B. G., Geirsson, H., and Hreinsdóttir, S.: Near real-time dike tracking using GNSS networks, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16118,, 2024.

Virtual presentation
Dario Delle Donne, Rebecca Sveva Morelli, Stefano Caliro, Maria Grazia Soldovieri, Aldo Benincasa, Ciro Buonocunto, Antonella Bobbio, Antonio Caputo, Sergio Gammaldi, Lucia Nardone, Francesco Rufino, and Massimo Orazi

Fumarolic and hydrothermal activities represent the shallow evidence of volcanic degassing within calderas, offering valuable insights for volcano monitoring. This phenomenon is particularly significant at the Pisciarelli fumarolic field in the Campi Flegrei caldera, Italy, where a continuous and vigorous release of hydrothermal and magmatic fluids occurs. This fumarolic outgassing is also associated with a persistent harmonic tremor and a persistent subtle infrasonic wavefield. Following the recent bradyseismic crisis at Campi Flegrei caldera, we established a permanent seismo-acoustic array to enhance real-time monitoring of temporal changes in fumarolic outgassing in Pisciarelli area. In particular, we exploited the seismo-acoustic wavefield produced by outgassing to assess its intensity and dynamics. Notably, we identified two distinct infrasonic sources, concurrently active and linked to 1) intense boiling in a water pool and 2) overpressurized steam release from fumarolic vents. The well-correlated temporal variations in infrasonic and seismic amplitudes offer insights into the hydrothermal system's outgassing mechanism. Specifically, they shed light on changes in the shallow hydrothermal reservoir pressure changes driving the outflow of hydrothermal gas. The integration of acoustic and seismic observations enhances our understanding of the dynamic nature of fumarolic outgassing at Campi Flegrei caldera. This improved understanding contributes to assessing volcanic risk for the caldera, as any modifications in fumarolic outgassing may indicate pressure changes in the hydrothermal reservoir.


How to cite: Delle Donne, D., Morelli, R. S., Caliro, S., Soldovieri, M. G., Benincasa, A., Buonocunto, C., Bobbio, A., Caputo, A., Gammaldi, S., Nardone, L., Rufino, F., and Orazi, M.: Real-time monitoring the hydrothermal outgassing of the active Campi Flegrei caldera through seismo-acoustic observations, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16954,, 2024.

Virtual presentation
Gokhan Karcioglu, Graham Hill, Max Moorkamp, Yann Avram, Colin Hogg, Sophia Gahr, Katharina Maetschke, Adam Schultz, Esteban Bowles-Martinez, Jared Peacock, Chaojian Chen, Corrado Cimarelli, Luca Caricchi, Yasuo Ogawa, and Duygu Kiyan

The main goal of volcano monitoring is to understand processes occurring within the magmatic system from there geophysical response signatures that informs on the eruptive behavior of the system. Traditional volcano monitoring approaches have relied primarily on changes in seismicity, and geodetic response which depend on active changes such as magma migration.

The magnetotelluric method, informs the physical property electrical conductivity, which within a magmatic context is sensitive to the presence of fluids, temperature, and melt fraction. High quality magnetotelluric measurements allow identification of conductivity variations related to the physical changes in magmatic systems, making it possible to determine temporal changes in magma content and temperature. Thus, magnetotellurics may be a valuable additional monitoring tool able to detect static phase changes of the magmatic fluids within the system, contributing to our understanding of the dynamics occurring within magmatic systems absent of and/or preceding magma movement within the system.

Mount St Helens as perhaps the most studied volcanic system including a dense 3D MT data set collected during the 2004-2008 dome building eruption provides the opportunity to investigate the difference within the magmatic system in different eruptive states (i.e. eruptive 2004-2008 and current quiescence). This is been achieved by a complete repeat of the initial survey (67 sounding locations) collected in 2005-06 and establishment of 4 ‘continuous’ telemetered systems. Given the current non-eruptive state of Mount St Helens a second system has been selected, Stromboli, currently in an eruptive cycle for installation of 4 continuous telemetered MT systems. Stromboli volcano, maintains a persistent eruptive activity, with near daily minor explosions typically punctuated by 1-2 larger events a year.

Initial evaluation of the streamed measurements has been completed using Phase Tensor parameters, which are immune to galvanic distortions, which can occur from seasonal near-surface conductivity changes (e.g. variations in soil moisture content). The Phase Tensor represents conductivity gradients in the subsurface, and Phase Tensor differences between two measurement times hence reflects the changes in conductivity structure in time. The temporal application of magnetotellurics provides a mechanism to determine short-term and long-term conductivity changes within the magmatic system representative of physical changes within the system, correlatable to active eruptive behavior, properties of the system during periods of quiescence and eruptive phases.

How to cite: Karcioglu, G., Hill, G., Moorkamp, M., Avram, Y., Hogg, C., Gahr, S., Maetschke, K., Schultz, A., Bowles-Martinez, E., Peacock, J., Chen, C., Cimarelli, C., Caricchi, L., Ogawa, Y., and Kiyan, D.: Electromagnetic monitoring of active volcanic zones: Monitoring of Phase Tensor parameters from Mount St Helens and Stromboli volcanoes, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5710,, 2024.

Coffee break
Chairpersons: Gaetana Ganci, Iestyn Barr, Jurgen Neuberg
On-site presentation
Aude Lavayssière, Sara Bazin, Pierre-Yves Raumer, and Jean-Yves Royer

With the vast majority of our planet volcanism occurring in the Oceans, moored networks of hydrophones have become efficient tools to monitor, and therefore better understand, underwater volcanic eruptions. As these instruments can record sounds from thousands of kilometers away, they are particularly relevant to detect earthquakes and volcanic eruptions remotely, allowing better geohazards assessment. In 2018, a major seismic and volcanic crisis gave rise to the Fani Maoré underwater volcano at 3500 m below sea level, ~50 km east offshore Mayotte, in the North Mozambique channel. The MAHY hydroacoustic network has been deployed in October 2020 to monitor the eruption and investigate the oceanic soundscape in the area. It consists of four hydrophones moored in the SOFAR channel in the water column around the volcano. Since their deployment, the hydrophones have continuously recorded all low-frequency sounds (0-120 Hz), particularly hundreds of impulsive signals resulting from the interaction between hot lava and cold seawater. An automatic detection method of these specific signals on spectrograms has been developed to investigate in details the spatio-temporal evolution of the new lava flows. This technique could be used worldwide to remotely detect and monitor active submarine eruptions in the absence of local monitoring networks or regular near-bottom seafloor surveys.

How to cite: Lavayssière, A., Bazin, S., Raumer, P.-Y., and Royer, J.-Y.: Hydroacoustic monitoring of submarine lava flows: the eruption of Fani Maoré volcano offshore Mayotte, Indian Ocean, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1642,, 2024.

On-site presentation
Dannie Hidayat, Hetty Triastuty, Dini Nurfiani, Widiwijayanti Christina, Yizhou Lou, Ahmad Basuki, Benoit Taisne, and Hendra Gunawan

After a long paused of eruption, Marapi Volcano in West Sumatra, Indonesia, started to erupt on 7 January 2023.  The eruption lasted for a couple of months.  It is followed by several months of quite period, the new, more violent eruption episodes occurred starting Dec 3, 2023 which are ongoing.  The study focus on episodes of January-February 2023 eruption to understand the volcano process, eruption behaviour compared to the past eruption and whether, in the hindsight there are precursors to the eruption that followed.  Compared to last recent episodes of eruptions, The January-February 2023 Marapi eruption consist of many explosions and degassing events. The time interval between explosions of Marapi in the beginning of eruptions, almost every hour there was an explosion, after a week time, the time interval became longer until no explosion occurred a month the first explosion.  We will also explore the mechanism of explosions from the infrasound data because the infrasound waveforms are simpler than those of the seismic waveforms. We observed the waveforms and the amplitude of infrasound in the beginning of eruption was simpler and very large at the station 300m from the active vent (> 50 Pa peak-to-peak) then the later explosions the amplitudes became smaller, and the waveforms became more oscillating coda.  This suggest the source, in the beginning it is filled with gas and fragmented magma and later the source is partially filled.  The explosions were also recorded by 4 other infrasound stations installed around the volcano up to the distance of 10 km from the vent.  Based on the observation seismicity several months prior to the first explosion of January-February 2023 Marapi eruption, there were distal volcano tectonic earthquakes clustered 4-5km the NW of the active crater.  The seismicity migrates to shallower depth below the active crater. This is supported by the observation of the tilt data from summit station and flank station, the tilt showed migration of pressure source for several months before the eruptions and that the magma pathway may probably located near the active fault zone.

How to cite: Hidayat, D., Triastuty, H., Nurfiani, D., Christina, W., Lou, Y., Basuki, A., Taisne, B., and Gunawan, H.: The characteristic of January-February 2023 Eruption of Marapi Volcano, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9964,, 2024.

On-site presentation
Christian Bignami, Emanuele Ferrentino, Lisa Beccaro, and Marco Polcari

In this study, microwave satellite images, and in particular Synthetic Aperture Radar (SAR), are used to detect volcanic lava flow. We propose methods that exploit both single and dual polarization channels to map the deposits that occurred in three case studies: the Etna Volcano (Italy) 2007-2008 eruption and the Sangay Volcano (Ecuador) eruption that took place in December 2021.

The objective of the work is to analyse the different information carried out by single and dual polarization data, in different volcanic environments, aiming to identify the most suitable solution for each setting.

For the Etna case study, we applied two change detection methods. The first one exploits the normalised difference and is used on a pair single polarization (SP) image captured by ENVISAT mission. The second method relies on the dual polarization (DP) data acquired by ALOS-PALSAR satellite. The latter is based on the covariance matrix derived from DP images, and the normalized difference of pre and post-event matrices.

As far as the Sangay case study, the results are undertaken over a pair of images collected by the C-band Sentinel-1 DP SAR sensor. The outputs are then analyzed to detect the different phenomena (i.e., lava flow, pyroclastic currents, landslides), that occurred over the scene.

The work demonstrates the complementary evidence provided by the co- and cross-polarized channels, suggesting the combination of them to obtain additional and more accurate information.

This activity is part of a INGV funded project, SAFARI - an AI-based StrAtegy For volcano hAzaRd monItoring from space, a research project that aims at developing a comprehensive space-based strategy for the near-real-time characterization of volcanic state of activity, based on the extraction of satellite-derived input parameters to physical models for rapid scenario forecasting during the eruptive phases.

How to cite: Bignami, C., Ferrentino, E., Beccaro, L., and Polcari, M.: Lava flow monitoring from EO microwave imageries, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19747,, 2024.

On-site presentation
Maddalena Dozzo, Federico Lucchi, and Simona Scollo

During explosive eruptions tephra fallout represents one of the main volcanic hazards and can be extremely dangerous for air traffic, infrastructures, agriculture, and human health.

The technological advancements and increasing availability of high-resolution satellite imagery have offered new possibilities for mapping volcanic deposits related to an individual eruptive event. Spatial resolution is one of the main limitations in deposit mapping, together with the revisit time of satellites, particularly in rapidly evolving situations.

Here we present a new technique aimed at identifying the urban areas covered by tephra after an explosive event based on the processing of PlanetScope satellite imagery. These recent multispectral data are acquired from a constellation of over 180 microsatellites and exhibits a relatively high spatial resolution (~ 3 m pixel size) covering once a day each point in the Earth surface.

Our technique is based on the introduction of a new index that we call ‘Tephra Fallout Index (TFI)’ computed from the mean reflectance values of the near infrared (NIR) band analyzing pre- and post-eruptive data in paved areas adjacent to the summit craters of Etna and more distal paved areas, to have an overall view of the distribution of the tephra deposit.

The objective of the proposed method is to find any variations between the pre- and post-eruptive reflectance values in the selected areas, exploiting the different ways that different materials exhibit (in this case tephra and cement) to reflect light.

We use the cloud-based geospatial analytic Google Earth Engine (GEE) computing platform and define a dynamic threshold for the TFI of different eruptive events to distinguish the areas affected by the tephra fallout. 

We demonstrate our technique by applying it to the eruptive events that occurred in 2021 at Mt. Etna (Italy), which mainly involved the eastern and south-eastern flanks of the volcano, sometimes two or three times within a day, making field surveys difficult. Whenever possible, we compare our results with field data and find an optimal match. 

The use of satellite imagery acquired from microsatellite constellations, such as PlanetScope, providing an optimal compromise between spatial and temporal resolution, may prove fundamental for identifying tephra deposits during eruptive episodes, such as those occurred in 2021 at Mount Etna volcano. Our method provides a near real time result, making it ideal also for the mapping of other hazardous events worldwide.

How to cite: Dozzo, M., Lucchi, F., and Scollo, S.: Exploiting satellite techniques for volcanic deposits mapping: the case of 2021 Mt. Etna eruptions, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7815,, 2024.

On-site presentation
Eva P. S. Eibl, William M. Moreland, Thorvaldur Thordarson, Ármann Höskuldsson, Egill Árni Gudnason, Gylfi Páll Hersir, and Thorbjörg Ágústsdóttir

The 2021 Geldingadalir eruption is the first of four eruption events that have taken place since volcanic activity resumed on the Reykjanes Peninsula, SW Iceland, after an 871-year repose. It lasted from 19 March to 18 September 2021 and featured (i) continuous effusion, (ii) episodic effusion on a minute scale, and (iii) episodic effusion on an hour to day scale. The eruption transitioned between these states several times, making it the most diverse eruption on record. We provide an overview of the eruptive processes during the entire eruption using video camera footage and seismic tremor data.

Our aim is to image the changes in the subsurface structure, to identify the driving processes, and to interpret the dynamics of the volcano. We will present our view on the most striking questions: What triggered the transition between these different states? What do these different effusion states mean in the context of the conduit and the shallow magma reservoir? What can we learn from the tremor amplitude, tremor duration and repose time of such episodic events?

How to cite: Eibl, E. P. S., Moreland, W. M., Thordarson, T., Höskuldsson, Á., Gudnason, E. Á., Hersir, G. P., and Ágústsdóttir, T.: Overview of the shallow magma reservoir, conduit properties and effusion style throughout the 2021 eruption near Fagradalsfjall, Iceland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11019,, 2024.

On-site presentation
Miriam Christina Reiss, Francesco Massimetti, Adele Campus, Georg Rümpker, Amani Laizer, and Emmanuel Kazimoto

Oldoinyo Lengai volcano is a strato-volcano in the eastern part of the East African Rift system and as such, a curious end member of a young magmatic segment: it is the only volcano worldwide that currently erupts carbonatitic lava. Known to alternate between large explosive (ash) and smaller effusive eruptions, we analyze volcanic tremor from Oldoinyo Lengai during a renewed phase of eruptive but non-explosive activity beginning in late 2018,  which we recorded with a seismo-acoustic network between March 2019 - June 2020 with the SEISVOL (Seismic and Infrasound Networks to Study the Volcano Oldoinyo Lengai) project. We focus on two different aspects of our data set, which are the very first observations of seismo-(acoustic) tremor at this peculiar volcano.

First, we analyze one year of data at a co-located seismic and infrasound station about 200 m below the summit together with satellite InfraRed thermal data and reconstruct different phases of volcanic activity (varying styles of extrusive activity, in particular spattering, degassing, activity from a lava pond, intrusive activity, and the construction of hornitos) and the evolution of crater morphology. We characterize the near-constant but highly variable tremor by analyzing its seismic amplitude, duration, recurrence, dominant seismic frequency and harmonics. Frequency gliding occurs frequently and over short (minutes to hours) to long time scales (hours to days). Seismic and acoustic wavefields correlate well for stronger eruptive sequences but are only partially coherent which suggests that high-frequency seismic tremor (up to 25 Hz) may be caused by the low viscosity of the carbonatitic melt.

Second, we focus on a selected number of seismic network stations to locate stronger tremors using the network-covariance matrix and a raytracing approach. While many tremors locate in the shallowest part of the edifice of Oldoinyo Lengai, supporting our previous analysis that much of the tremor is caused by eruptions, tremors are also located in the crust to depths of ~15 km. Most importantly, strong (gliding/harmonic) tremor seems to be connected to a migration of tremor depths which mostly locate in rock volumes not associated with seismicity. This suggests we may be able to use tremor to study melt and fluid pathways in the mushy part of a volcanic plumbing system. Overall, our study provides important insights into the eruption dynamics, as well as melt transport and storage of this peculiar volcano.

How to cite: Reiss, M. C., Massimetti, F., Campus, A., Rümpker, G., Laizer, A., and Kazimoto, E.: Illuminating eruptions, fluid pathways and melt storage with seismo-(acoustic) tremor at Oldoinyo Lengai volcano, Tanzania, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9467,, 2024.

On-site presentation
Thoralf Dietrich, Eva P.S. Eibl, Kristin S. Vogfjörd, Sebastian Heimann, Morgan T. Jones, Benedikt G. Ófeigsson, Matthew J. Roberts, and Christopher J. Bean

Ice-covered volcanoes regularly cause subglacial floods called jökulhlaups. These may be caused by volcanic eruptions but more often they are associated with geothermal activity beneath the ice. Within this presentation we will study the largest jökulhlaup on record in Iceland using GPS sensors above the flood path, hydrological sensors and geochemical measurements in the affected river and a seismic array in combination with the local seismic network.

We detected four different tremor types: (1) Migrating tremor and high-frequency transient events follow the propagation of the flood front. (2) Minute-long tremor bursts occur in the cauldron area once the water has drained from the subglacial lake and (3) each one is followed by hour-long harmonic tremor. (4) Tremor due to more energetic flow in the rapids near Sveinstindur in the Skaftá river.

Interestingly, families of icequakes were generated in the area around the cauldron, during the onset of the flood. This grouping into families - and their consecutive activation with time - suggests that we see the gradual collapse of the ice shelf above the subglacial lake seismically.

The flood generated five different seismic signal types that can be associated with five different geophysical processes, including the wide spectrum from brittle failure and explosions to boiling and turbulent flow. We will discuss these sources in detail in the presentation.

How to cite: Dietrich, T., Eibl, E. P. S., Vogfjörd, K. S., Heimann, S., Jones, M. T., Ófeigsson, B. G., Roberts, M. J., and Bean, C. J.: An overview of tremor and icequake types during the 2015 Eastern Skaftá jökulhlaup, Iceland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17498,, 2024.

On-site presentation
Johann Helgason

Sheet-like sequences may form in relation to subglacial volcanism. Such sequences are thought to be of two types: Mount Pinafore and Dalsheiði-type. The Mount Pinafore-type presumably forms under thin ice cover or some 150-200 m, whereas the Dalsheiði-type is thought to form under much thicker ice cover or probably ˃ 1000 m. Dalsheiði-type sequences are well known in Iceland and were first described by Walker and Blake for Dalsheiði in SE-Iceland. They assumed the pillows and breccia developed through escape upwards and sideways from the basalt into the overlying glacier or its meltwater. A considerably more widespread Dalsheiði sequence was later mapped by Bergh in the Síða-Fljótshverfi of S-Iceland.

Walker and Blake (1966) mapped the Dalsheiði sequence near the assumed eruptive source by Lambatungnajökull (at 628 m a.s.l.) over a 20 km distance down to heath Dalsheiði (at 200 m a.s.l.). New work by Dalsheiði area has revealed that the sequence is more widespread than previously mapped, extending 5 km further down slope to Þórisdalur, or to 20 m a.s.l. I, the sequence differs drastically from the upper segment in that pillows and breccia are rare but extensive sheet-like units dominate. Here, the sills and pillows are typically nonvesicular and dense. Near the edge of the sequence one sheet is seen to intrude into underlying sedimentary rock as evidenced by “fingered” units where the sill intrudes a hydrothermally altered sediment, a host that presumably had brittle to ductile properties. Most Dalsheiði sequences have a thick hyaloclastite body above a sheet of basalt that presumably intruded the ice/bedrock boundary. The lack of a hyaloclastite body by Þórisdalur and the abundant sill-like intrusive sheets there strongly suggests that the first phase in sheet-like sequence formation are intrusions into the ice sheet/bedrock boundary.

By Þórisdalur the sheets have 1-2 m thick colonade at the base, grade into some 6 m thick entablature fracture part, and at the top a 4-5 m segment with still finer fractures and white secondary minerals. Total absence of vesiculation in the lowest sequence of the Dalsheiði formation by Þórisdalur supports that the intruding magma was confined below thick ice that suppressed magma-water explosivity. The interface sills by Þórisdalur may the best such examples discovered to date and in excellent agreement with the theoretical model proposed by Wilson and Head (2002) for injection of such magma sills at the ice sheet lower base. Furthermore, the dominating sill-like character of the Dalsheiði formation by Þórisdalur and intrusion into underlying sedimentary rock, is in contrast with the Sída formation of S-Iceland where a sill-like unit typically interacts with a thick overlying hyaloclastite unit. At Þórisdalur the hylaoclastite phase is missing suggesting that that pillows, breccias and hyaloclastite form at a later stage on top of the sill, perhaps when a meltwater lense has accumulated there, and that this later stage may not have taken place in Þórisdalur.

How to cite: Helgason, J.: New additions to the Dalsheiði sheet-like formation in Þórisdalur, SE-Iceland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6723,, 2024.

On-site presentation
Audrey Putnam, Kirsten Siebach, Candice Bedford, Sarah Simpson, Elizabeth Rampe, Joseph Tamborski, and Michael Thorpe

Volcanism increases when glaciers melt because isostatic rebound during deglaciation decreases the pressure on the mantle, which enhances decompression melting. Anthropogenic climate change is now causing ice sheets and valley glaciers to melt around the world and this deglaciation could stimulate volcanic activity and associated hazards in Iceland, Antarctica, Alaska, and Patagonia. However, current model predictions for volcanic activity associated with anthropogenic deglaciation in Iceland are poorly constrained, in part due to uncertainties in past volcanic output over time compared to ice sheet arrangements. Further work specifically characterizing glaciovolcanic and ice-marginal volcanoes in Iceland is needed to reconstruct volcanic output during time periods with changing ice cover. Here, we describe a previously unrecognized ice-marginal volcanic lava delta on a broad, shallow slope southeast of Langjökull and the Jarlhettur volcanic chain in Iceland’s Western Volcanic Zone.


Although previously mapped as interglacial lavas and sediments, canyons in this area revealed two ~20-30 meter-thick southwest-dipping sequences of pillow-bearing tuff-breccias between pāhoehoe lava flows above modern lake Sandvatn. Clasts within the tuff-breccias include a mixture of pillow lavas and pāhoehoe fragments, requiring that the subaqueous tuff-breccia facies were derived from subaerial flows. The upper subaqueous to subaerial transition in this sequence occurs around 400 m above sea level, much higher than any local topography that could dam water or the highest Icelandic marine transgression, necessitating ice damming. Quenched meter-scale cavities in coherent lava and cube-jointed facies show lava-ice contact, supporting evidence for an ice dam. We propose that an eruption melted through thin ice near Skálpanes during a deglacial period and lavas flowed downslope to the south, melting ice and forming an englacial lake. We constrain that the local ice thickness was tens of meters to a few hundred meters thick. This would represent a similar ice configuration as some interpretations of the ice extent at the time of formation of the Buði moraines around 11.2 ka, with higher ice flow down the valley of the Hvita river than off Langjökull, although it occurred during an earlier deglaciation. Importantly, this finding demonstrates that ice-marginal deposits that can provide paleo-environmental constraints may be hidden in terrains that do not conform to existing classifications of glaciovolcanic edifices.

How to cite: Putnam, A., Siebach, K., Bedford, C., Simpson, S., Rampe, E., Tamborski, J., and Thorpe, M.: Ice-marginal lava delta in Iceland found on a nondescript shallow slope: An unexpected record of ice thickness late in deglaciation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-13612,, 2024.

Virtual presentation
Magnus Tumi Gudmundsson, Thordis Hognadottir, Hannah I. Reynolds, Eyjolfur Magnusson, and Finnur Palsson

About 10% of Iceland is covered by glaciers, including three of the four most active central volcanoes, Grímsvötn, Katla and Bárðarbunga, where the ice-filled calderas have glacier thickness of several hundred meters.  Ice cauldrons, defined as circular or elongated depressions in the surface of glaciers which form due to enhanced basal melting, are very common in the ice-covered volcanic areas in Iceland.  Many have concentric crevasses.  Over 100 cauldrons have been identified in the glaciers of Iceland, with over half being located within or adjacent to the calderas of Grímsvötn, Katla and Bárðarbunga.  Ice cauldrons are usually a sign of subglacial geothermal activity, while occasionally cauldrons are formed during subglacial volcanic eruptions.  Some cauldrons are short term features, existing for some years, indicating transient geothermal activity or recent occurrence of a volcanic eruption.  Others are semi-stable features that have existed for several decades, possibly centuries.  Stable cauldrons are always associated with geothermal activity and the same applies to many of the intermittently active ones as well.  Cauldrons formed in volcanic eruptions tend to be deep and with larger depth/width ratios than geothermal cauldrons.  The widest cauldrons observed in Iceland reach 4-5 km in diameter while diameters of 0.5-1.0 km are the most common.   The size and form of geothermal ice cauldrons depends to a considerable degree on the ice thickness.  Where thickness is small (<100 m), cauldrons can be holes with steep slopes or vertical ice walls and may in some cases reach the base of the glacier.  Where ice thickness exceeds 200-300 m, geothermal cauldrons rarely form vertical ice walls.  In most cases, it is clear which cauldrons are formed by sustained geothermal activity. Volcanic cauldrons tend to reach their maximum size rapidly, followed by gradual decline as the erupted volcanic material loses its heat quickly and ice flow gradually fills the depression.  However, despite gradual infill by ice flow and reduction in cauldron depth, volcanically formed depressions may persist for decades.  An example of this is the tens-of-meters deep and 2-3 km wide depression at the site of the 1996 Gjálp eruption, which is still visible.  Ice thickness at this site was ~600 m prior the eruption. Beneath some ice cauldrons meltwater accumulates at the base of the glacier.  This may result in semi-periodic release of meltwater in jökulhlaups.  Other cauldrons may drain more or less continuously. 

How to cite: Gudmundsson, M. T., Hognadottir, T., Reynolds, H. I., Magnusson, E., and Palsson, F.: Ice cauldrons and their relationship with volcanic and geothermal activity in ice-covered volcanoes in Iceland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18805,, 2024.

Posters on site: Mon, 15 Apr, 10:45–12:30 | Hall X1

Display time: Mon, 15 Apr 08:30–Mon, 15 Apr 12:30
Chairpersons: Gaetana Ganci, Jurgen Neuberg, Miriam Christina Reiss
Giulia Fisauli, Maurizio Petrelli, Alessio Di Roberto, and Giuseppe Re

We don’t always have direct access to volcanoes especially those located in hostile and remote areas of our planet, such as Antarctica. Moreover, the knowledge of the Antarctic continent and its volcanoes is still limited by the scarce exposure of volcanic rocks due to the extensive glacial cover, since only 1% of the total area is ice-free. Pyroclastic deposits (i.e. tephra) represent a very effective and powerful tool for petrological and volcanological studies. Through the study and characterization of tephra we can get information about the evolution of magmas, including their physical, chemical and mineralogical characteristics. Additionally, we can get a new understanding of the architecture of volcanic plumbing systems, the nature and intensity of eruptions as well as the emplacement dynamics, their aerial transportation and their impacts on Earth. This work focuses on the characterization of tephra originating from three distinct volcanoes of the Northern Victoria Land, Mount Melbourne, Mount Rittmann and The Pleiades.

According to previous studies, the activity of Mount Melbourne can be dated back to approximately 1892 CE, this is also confirmed by the presence of several tephra layers in the summit and flanks of the volcano (Lyon, 1986). Evidence for explosive eruptions of Mount Melbourne volcano between 1615 cal. yrs BP and 1677 cal. yrs BP were recently acquired (Di Roberto et al. 2023). Also, Mount Rittmann erupted in historical time (696 ± 2 cal. yrs BP) and the presence of fumaroles and summit geothermal activity indicate that the volcano is still active. However, we still know very little about the volcanic history of this volcano. The Pleiades volcanoes instead show evidence of activity during the Holocene (Di Roberto et al. 2020).

Despite the abundance of rock samples collected in this area, there is still a scarcity of both geochemical and petrological data and studies.

We analysed 23 samples that have been collected over the last 30 years during Antarctic expeditions. The analyzed data will provide a more detailed understanding of past explosive volcanic activity including source, magnitude, intensity, chemical evolution and eruptive dynamics. Finally, this will also improve the correlation between proximal and distal tephra.

In addition, an extensive database containing major and trace elements is crucial for a precise geochemical characterization to provide invaluable insights to enhance our understanding of the Northern Victoria Land.

The comprehension of Antarctic volcanism is crucial not only to understand the eruptive dynamics and plumbing system but also to build new knowledge of the history of explosive volcanic activity through time and space. This understanding is critical in evaluating and defining potential impacts associated with future eruptions, which could potentially be affected by ice dynamics and ice load covering the volcanic structures, with wider implications for our planet.


Lyon, G.L., 1986. Doi: 10.1080/00288306.1986.10427528.

Di Roberto et al. 2020. Doi: 10.1016/j.quascirev.2020.106629

Di Roberto et l. 2023. Doi: 10.1016/j.qsa.2023.100079


How to cite: Fisauli, G., Petrelli, M., Di Roberto, A., and Re, G.: Proximal tephra characterization in Northern Victoria Land, Antarctica: Insights into eruptive history and future implications, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3639,, 2024.

Pierdomenico Romano, Prospero De Martino, Bellina Di Lieto, Annarita Mangiacapra, Zaccaria Petrillo, and Agata Sangianantoni

Campi Flegrei Caldera is an active volcano located westward of Naples, Italy. Despite its volcanic activity spanning over 39,000 years, the area is densely populated and poses a significant threat to the inhabitants due to ongoing seismicity, ground uplift, and hydrothermal activity resulting from increased pressure due to fluid injections and thermal variations at depth. These factors highlight the potential for a major volcanic eruption. Being able to model the processes that lead to ground deformation could be of vital importance in predicting an imminent eruption and enabling the evacuation of the resident population in the area.

Such models are being schematized and analyzed using specific Finite Element Method (FEM) software capable of solving complex mathematical problems involving partial differential equations. In this manuscript, we utilized COMSOL Multiphysics, configured with the structural mechanics module, to examine how deep changes in pressure and temperature influence the observed surface deformation field within the Campi Flegrei caldera. To simulate these deep changes, we employed the Tough software, an open-source numerical simulation program designed for multi-dimensional fluid and heat flows of multiphase and multicomponent fluid mixtures in porous and fractured media. The output of Tough served as an input for the COMSOL model, representing the source at depth. By using the structural mechanics module, we were able to assess the accuracy of the proposed model in comparison to analytical solutions. Furthermore, we were able to model the geometry of the deep source in more detail and verify that the surface deformation pattern aligned with the measurements obtained from sensors. By leveraging COMSOL Multiphysics, therefore, we have constructed a mathematical model that accurately captures the intricate interplay of fluid injections, thermal variations, and rock mechanics, enabling us to simulate volcanic crustal deformations with remarkable fidelity: the surface deformations obtained through simulation aligns with those observed through GPS/GNSS, strain and tilt time series recorded by the Osservatorio Vesuviano monitoring networks.

Valuable information are embedded in the data used in the current work, which could be used not only for scientific purposes but also from civil protection for monitoring reasons. Such a variety of possible usage needs the setting of principles and legal arrangements to be implemented in order to ensure that data will be properly and ethically managed and in turn can be used and accessed from the scientific community.

How to cite: Romano, P., De Martino, P., Di Lieto, B., Mangiacapra, A., Petrillo, Z., and Sangianantoni, A.: FEM model of surface deformation pattern and a first application on real data at Campi Flegrei caldera, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18088,, 2024.

Flavio Manara, Marceau Gresse, André Revil, Anthony Finizola, and Tullio Ricci

Geo-electric exploration surveys such as Electrical Resistivity Tomography (ERT) can provide valuable insights regarding the characterization of geological structures and hydrothermal systems in volcanic environments. However, while ERT is a powerful tool, its effectiveness can be limited by the inherent sensitivity of rock electrical conductivity to various parameters. These can include factors such as water content, salinity of pore water, rock temperature, or alteration. Each of these factors significantly impacts the results of an ERT survey and, if not precisely characterized, can lead to inaccurate data interpretation. As a result, ERT is often supplemented by additional costly and time-consuming in-situ measurements, such as soil temperature or diffuse soil CO2 degassing probing, to provide a more comprehensive analysis of subsurface conditions.

The purpose of this study is to summarize the recent geophysical findings from Revil et al. (2023), where they constructed the first 3D electrical conductivity model of the Stromboli volcano in the Aeolian Islands. To build this model, Revil et al. collected and analyzed data from various sources, including self-potential, soil temperature, soil CO2 degassing, and thermal remote sensing maps. By comparing these complementary datasets, this study aims to highlight the benefits of using Thermal Remote Sensing as a supplementary tool to analyze data from subsurface geo-electric exploration. Thermal remote sensing constitutes a practical and cost-efficient approach, allowing for systematic monitoring of Earth’s surface thermal anomalies via infrared imaging down to a spatial resolution of 30 to 15 meters.  By applying corrections and isolating surface-emitted radiance from the integrated signature received by the satellite, the average temperature of the surface is retrieved for each pixel. Thermal anomalies on the volcano are then located, and their temperatures are accurately determined through dual-band processing, which involves comparing images from Thermal Infrared and Short-Wave Infrared spectra.

The maximum remotely recorded infrared temperature is 792°C, associated with the main active volcanic vents. Considering the extreme heterogeneity in surface temperature at the scale of the pixel as well as the presence of volcanic gases, uncertainties for the remotely acquired temperature are in the range of a few degrees centigrade. The soil temperature measurements near these vents, retrieved at a depth of 30 cm, also reveal significant internal activity with temperature values reaching 100°C (the readings were taken to a tenth of a degree). This high-temperature region perfectly matches the positive anomalies of self-potential and diffuse soil CO2 degassing associated with the vertical conductive channel (1 to 10-1 S/m).

In conclusion, the ability to isolate the temperature associated with the thermally active component makes this approach highly promising for accurately constraining the spatial distribution of the shallow hydrothermal system, as it is manifested at the surface by high-temperature areas. Therefore, thermal remote sensing appears very useful in refining the interpretation of subsurface geophysical images.

How to cite: Manara, F., Gresse, M., Revil, A., Finizola, A., and Ricci, T.: Enhancing Geo-electric Exploration using Thermal Remote Sensing and Dual Band Processing – Case Study of the Stromboli Volcano (Aeolian Islands), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3878,, 2024.

Salvatore Gambino, Laura Privitera, Alessandro Bonaccorso, Giuseppe Falzone, Giuseppe Laudani, and Angelo Ferro

Etna is a very active volcano with frequent eruptions and it is well controlled through different monitoring techniques. Continuous control of ground deformation is also provided by tilt measurements especially through a network of short-base borehole sensors. Since 1996 this network has been integrated with a long-base fluid tiltmeter installed in two 80 m long tunnels present at the high altitude (2,850 m a.s.l.) volcanological observatory of Pizzi Deneri (PDN) located on the summit area of the volcano. The instrumentation was created with an innovative configuration composed of mercury, free to move along the entire length of 80 m in response to the ground tilt, and laser sensors to measure the changes of the mercury level at the ends of the length where this fluid is positioned. In this study for the first time we present the entire set of 25 years of data (1997-2022) recorded by this instrumentation. During this long time interval, the Etna volcano was characterized by numerous main eruptions due to dyke intrusions. The tilt variations recorded in the short term during the rapid intrusive phases are presented and discussed. These signals contributed to the modeling of eruptive processes, and in particular in the case of the 2002-2003 eruption they contributed to the real-time understanding of the ongoing eruptive phenomenon, supporting the correct hazard assessment. In the medium-long term (years to decades) the signal maintained a trend that cumulated approximately 200 microrads on both components during the entire observation. PDN long term is primarily affected by the dynamics of the marked sliding of the entire eastern sector of the volcano.

How to cite: Gambino, S., Privitera, L., Bonaccorso, A., Falzone, G., Laudani, G., and Ferro, A.: 25 years recording of the long-base fluid tiltmeter installed at 2.850 m a.s.l. observatory on Etna volcano, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7370,, 2024.

Vittorio Minio, Luciano Zuccarello, Silvio De Angelis, Giuseppe Di Grazia, and Gilberto Saccorotti

Volcanic activity generates diverse seismic and acoustic signals that offer valuable insights into the underlying magmatic processes. Contemporary volcano monitoring relies on networks and arrays of seismic and acoustic sensors. The analysis of signals acquired by these instruments necessitates streamlined workflows and specialized software. The high sampling rates, typically exceeding 50 Hz, employed in recording seismic and acoustic waveforms by multi-station networks and dense arrays result in the swift accumulation of substantial data volumes, posing a formidable challenge in establishing efficient data analysis workflows for volcano surveillance.
In this context, we introduce MISARA (Matlab Interface for Seismo-Acoustic aRray Analysis), an open-source MATLAB graphical user interface. MISARA is meticulously crafted to furnish a user-friendly workflow for analyzing seismo-acoustic data in volcanic settings. It incorporates efficient algorithmic implementations of established techniques for seismic and acoustic data analysis, with a focus on supporting the visualization, characterization, detection, and location of volcano seismo-acoustic signals. The intuitive and modular structure of MISARA facilitates swift, semi-automated data inspection and result interpretation, thereby minimizing user effort.
Validation of MISARA involved testing it with seismo-acoustic data recorded at Etna Volcano (Italy) during 2010, 2011, and 2019. The tool is intended for educational and research purposes and is well-suited to aid routine data analysis at volcano observatories. Its open-source nature encourages collaborative development and adaptation, fostering advancements in volcano monitoring and contributing to the broader scientific community.

How to cite: Minio, V., Zuccarello, L., De Angelis, S., Di Grazia, G., and Saccorotti, G.: Matlab Interface for Seismo‐Acoustic aRray Analysis (MISARA), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7541,, 2024.

Giovanni Macedonio, Louise Cordrie, Antonio Costa, Flora Giudicepietro, Francesco Obrizzo, Elena Cubellis, and Eliana Bellucci Sessa

The eruption of Vesuvio in 1944 commenced on the 18th of March and concluded on the 29th, encompassing both eruptive and seismic activities. After that date the activity decreased and has continued with low intensity until April 7, when the eruption was declared over, the crater was completely obstructed and the closed conduit period of the volcano began, which has lasted until now. During the paroxysm, the volcano underwent four distinct phases: effusive, lava fountaining, mixed explosions, and explosive events. In the initial phase (from the 18th to the 21st), the resulting lava field attained a total volume of 10^6 m^3 and a length of 5.6 km, distributed across various flows. The recent acquisition of a digitized pre-eruption Digital Elevation Model (DEM) for the region facilitates a more accurate estimation of the thickness of the final lava field by comparing it to post-eruptive LIDAR DEM data. Utilizing VLAVA, a simulation code designed for modeling lava flow propagation over complex topography with temperature-dependent viscosity, accurate modeling of the effusive phase has been achieved. These simulations contribute to a better characterization of the 1944 Vesuvius lava flow emplacement and a deeper understanding of lava flow rates from multiple vents and the subsequent lava propagation dynamics.

How to cite: Macedonio, G., Cordrie, L., Costa, A., Giudicepietro, F., Obrizzo, F., Cubellis, E., and Bellucci Sessa, E.: Modelling the effusive phase of the 1944’s Vesuvio eruption using VLAVA, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17223,, 2024.

Marco Spina, Giuseppe Bilotta, Annalisa Cappello, Maddalena Dozzo, Roberto Guardo, Francesco Spina, Francesco Zuccarello, and Gaetana Ganci

Automated early warning systems for volcanoes, capable of early recognition of any signs of impending eruption, as well as to track the evolution of different kinds of eruptive activity in near real time, are essential to assess the volcanic hazards and mitigate the associated risk. Satellite imagery offers a systematic, synoptic framework for monitoring active volcanoes in even the most isolated corners of the Earth. 

Here we have applied a machine learning technique to automatically classify a pixel in SEVIRI imagery over an active volcano, in order to detect and characterize its eruptive activity. In particular, we have discriminated against five main classes of pixels: clear sky, cloud-contaminated, ash-contaminated, SO2-contaminated and thermal anomalies.

Due to the enormous amount of data and the difficulty in labeling it, we have used self-supervised learning to study data acquired since 2004. We have selected an area of 5x5 pixels around the active volcano under study and followed the spectral radiance variation of each pixel in the twelve bands availables. 

Our technique has been applied to several active volcanoes within the SEVIRI disk, including Etna, Nyiragongo, Stromboli, Nabro, La Palma and Fogo.

How to cite: Spina, M., Bilotta, G., Cappello, A., Dozzo, M., Guardo, R., Spina, F., Zuccarello, F., and Ganci, G.: Volcanic activity classification trough Self-Supervised Learning applied to satellite radiance time series, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8046,, 2024.

Annalisa Cappello and the PANACEA team

Volcanic risks cannot be stopped or eliminated, but their effects can be minimized by applying new methods and providing data to support decision-making processes. Etna is one of the most active volcanoes in the world, producing both effusive and explosive eruptions, together with very intense seismic activity, which significantly influence the territory and society. The PANACEA project intends to address some issues that are still open in the modeling and integration of risks deriving from seismic and volcanic hazards, in order not to be caught unprepared and implement proactive risk reduction policies. In particular, the project has focused on the: (i) classification and statistical analysis of the historical eruptions of Etna; (ii) revision of the historical earthquake catalogue and the related database of macroseismic intensities; (iii) assessment of the long-term probability of vent opening based on historical eruptions and seismicity; (iv) extraction of the input parameters to run numerical simulations; (v) physics-based modeling of complex geophysical flows; (vi) probabilistic hazard mapping for single eruptive products, i.e. lava, tephra fallout and PDCs; (vii) probabilistic seismic hazard assessment; (viii) harmonization of the different hazards in a single long-term hazard map; (ix) analysis of the possible interactions at the hazard and the vulnerability levels, in order to quantitatively update hazard and risk estimations; (x) exposure and vulnerability assessment of elements at risk; (xi) multi-risk analysis by combining multi-hazards, exposure and vulnerability assessment. The results of PANACEA demonstrate that a better understanding of geophysical flow mechanisms, as well as improvements in knowledge in volcanic and seismic multi-hazard and multi-risk assessment, both in conceptual and technological terms, provide a powerful tool to develop effective and operational strategies, improving safety and reducing the impact of Etna's eruptive events.

How to cite: Cappello, A. and the PANACEA team: The PANACEA project: Probabilistic AssessmeNt of volCano-related multi-hazard and multi-risk at Mount EtnA, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5354,, 2024.

Malvina Silvestri, Maria Fabrizia Buongiorno, and Vito Romaniello

The THERESA project, which stands for THErmal infRarEd SBG Algorithms, seeks to improve algorithms for processing data obtained from the SBG-TIR (Surface Biology and Geology – Thermal InfraRed) mission. By leveraging the mission's technical features, THERESA aims to improve and adapt specific algorithms to study geological processes and develop new ones that could get advantages by using SBG-TIR spectral channels in the VIS and MIR-TIR range. Over the two-year duration of the project, THERESA will play a vital role in advancing the study of terrestrial phenomena also considering the high revisit time of SBG, which will be of 3 days worldwide over land.

SBG-TIR data will benefit diverse thematic areas, ranging from vegetation analysis to monitoring volcanic eruptions and fires. The project aims to derive several key parameters, including the estimation of ash and SO2 emissions from volcanoes, surface temperature, detection of hotspots, and the calculation of FRP (Fire Radiative Power) during High Temperature Events (HTEs). THERESA distinguishes itself through its innovative algorithmic advancements, providing comprehensive support to the SBG-TIR mission. Finally, suitable sites for CAL/VAL activities will be identified, and measurement campaigns will be conducted coinciding with the passages of currently operational TIR satellites for the validation of the algorithms under study.

How to cite: Silvestri, M., Buongiorno, M. F., and Romaniello, V.: THERESA project: a study to enhance algorithms for processing data from the SBG-TIR mission in volcanological field, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4989,, 2024.

Andreas Krietemeyer and Elske de Zeeuw-van Dalfsen

The evolution of cost-efficient Global Navigation Satellite System (GNSS) equipment sparked increasing scientific interest to use this technology for precise geophysical measurements. In this research, we investigate the use of cost-effective GNSS units for deformation monitoring on the island of Saba in the Caribbean Netherlands. Saba hosts Mt. Scenery, an active but quiescent stratovolcano in the Lesser Antilles Volcanic Arc. The most recent eruption of the 887 metres high volcano occurred around 1640.

In February 2022, four cost-effective GNSS units were installed on the island to densify the existing Royal Netherlands Meteorological Institute (KNMI) GNSS network of four permanent GNSS stations. While the equipment costs of a permanent GNSS station quickly exceeds 10.000 Euro, the cost-efficient units come at a price of about 1000 Euro. The cost-effective unit’s design includes all necessities for independent operation: Solar charger, microcontroller, cellular data transmission, as well as remote connection via the cellular 4G connection. Compared to permanent GNSS stations, the cost-effective unit’s installation time in the field is significantly reduced.

We present the GNSS unit’s design and first deformation monitoring results of the deployed stations. The data is validated by comparing data of a cost-effective unit with those from a permanent GNSS station next to it. The GNSS units are well suited to monitor ground deformation on Saba as their daily positioning precision is similar to those of permanent GNSS stations. The cost-efficient GNSS units can therefore be used i) to expand existing deformation monitoring networks, ii) in stand-alone areas where the installation of conventional GNSS is deemed too costly, or iii) in risk-prone areas where rapid installation of expendable equipment is necessary.

How to cite: Krietemeyer, A. and de Zeeuw-van Dalfsen, E.: Advancing Volcano Monitoring Capabilities: Deployment of Cost-Efficient GNSS Units in the Lesser Antilles on Mt. Scenery, Saba, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8653,, 2024.

Alberico Grimaldi, Silvia Scarpetta, Ortensia Amoroso, Vincenzo Convertito, Danilo Galluzzo, Giovanni Messuti, Ferdinando Napolitano, Guido Gaudiosi, Lucia Nardone, and Paolo Capuano

The Campi Flegrei caldera, located in Southern Italy, is one of the most hazardous volcanoes in the world. Seismic activity in the caldera has increased in the last year due to a new unrest phase of the volcano. This has driven the attention of the scientific community and both local and national media. The Campi Flegrei area is densely populated, with a very low signal-to-noise ratio, making the detection of small earthquakes or the recognition of non-seismic events more challenging.

This study introduces a novel approach to the detecting and clustering of seismic signals. Unlike conventional methods that primarily focus on the regularity of seismic patterns, our research pivots towards a complexity-centric perspective using the Multiscale Entropy (MSE) algorithm, in conjunction with the Self-Organized Map (SOM) algorithm for effective data clustering. This methodological shift allows for a more nuanced exploration of the intricate dynamics inherent in seismic activities.

Seismic signals are not random or chaotic but rather complex structures that vary across different scales. By employing the MSE algorithm, we unravel these complex patterns, offering insights into the seismic behaviours that traditional methods may overlook. Our findings indicate a significant correlation between the complexity of seismic signals and key geophysical events related to the dynamic of the volcano, suggesting that complexity analysis could be a significant tool in seismic monitoring and prediction.

The analysed dataset is a six-month long continuous signals recorded in period at the V0102 temporary seismic station installed by the INGV-Osservatorio Vesuviano close to the Pisciarelli area, located in the Campi Flegrei caldera. MSE has been applied to one-minute-long traces of signal and clusterized through the application of the SOM analysis, revealing hidden layers of complexity across multiple scales.

Moreover, the study explores the potential of integrating MSE analysis with other seismic analysis techniques to enhance the accuracy of seismic interpretations. By combining complexity analysis with traditional approaches, we aim to develop a more deep and comprehensive understanding of seismic signals, potentially leading to an improvement of the seismic risk assessment.

How to cite: Grimaldi, A., Scarpetta, S., Amoroso, O., Convertito, V., Galluzzo, D., Messuti, G., Napolitano, F., Gaudiosi, G., Nardone, L., and Capuano, P.: Multiscale Entropy (MSE) and Self Organizing Map (SOM): two useful tools for the interpretation of seismic signals in the Campi Flegrei Caldera, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8686,, 2024.

Flavio Cannavo, Vittorio Minio, Eugenio Privitera, Bellina Di Lieto, Pierdomenico Romano, Lorenzo Innocenti, Giorgio Lacanna, and Maurizio Ripepe

Monitoring volcanic activity is a complex task, given the intricate nature of volcanic processes and the diverse eruptive styles exhibited by different volcanoes. Early Detection (ED) systems have emerged as indispensable tools for mitigating potential risks associated with volcanic eruptions. The effectiveness of these systems is contingent upon their ability to provide timely and accurate alerts, as false alarms or missed warnings can lead to economic repercussions and pose risks to infrastructure and human safety. Evaluating the reliability of the ED systems may be paramount not only for effective hazard mitigation but also for facilitating the implementation and optimization of an ED model. However, developing an ED model is a challenging and labor-intensive endeavor, also requiring a deep understanding of advanced techniques and a meticulous calibration of various parameters. 

In response to these challenges, we present the Framework for Evaluation of Early Detection Systems (FEEDS). FEEDS is a comprehensive Python-based package designed to automatically assess the generalization capability of generic ED systems through cross-validation. The framework introduces a generic class representing the ED model identified solely through data, enabling a systematic assessment based on essential predictive parameters, including True Positive Rate, False Discovery Rate, prediction time, and Fraction of Time in Alarm, by performing a simulation. 

To validate the effectiveness of FEEDS, we utilized tiltmeter and strainmeter data recorded at Stromboli volcano between 2007 and 2019. These datasets, managed by Istituto Nazionale di Geofisica e Vulcanologia and Università di Firenze, were employed to implement FEEDS with a customized model for the early detection of the paroxysmal activity affecting the volcano during the period of the study, demonstrating the practical applicability and reliability of this framework in real-world volcanic monitoring scenarios.

FEEDS may represent a valuable contribution to the ongoing efforts to enhance ED systems and their application in mitigating volcanic hazards. The development of a robust framework that automates the standard evaluation process not only streamlines system implementation but also reduces user efforts and establishes a common ground for assessing the reliability and performance of different ED models, contributing significantly to the advancement of volcanic monitoring capabilities.

How to cite: Cannavo, F., Minio, V., Privitera, E., Di Lieto, B., Romano, P., Innocenti, L., Lacanna, G., and Ripepe, M.: FEEDS: Validation of the Framework for Evaluation of Early Detection Systems, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10514,, 2024.

Rosie Cole, Magnús Tumi Gudmundsson, Elisa Piispa, Birgir Óskarsson, Catherine Gallagher, Brian Jicha, and Wesley Farnsworth

It has been established through geochemical and geophysical models that, in Iceland, unloading of the Pleistocene ice sheet at the end of the last glacial period resulted in a peak in magma production and volcanic activity. Environmental differences are recorded in volcanic products, but mostly between discrete monogenetic glaciovolcanoes and postglacial lava flows. In areas of frequent and persistent activity, the way in which physical eruption styles evolved with changing ice thickness and glacial hydrology has received less attention. We examine a sequence of volcanic products exposed in the dissected flanks of Katla and Eyjafjallajökull, two ice-capped volcanoes that have been active beneath fluctuating glacial cover from the Pleistocene to present day. We use traditional geological mapping combined with photogrammetry surveys, major element geochemistry, paleomagnetic techniques and radiometric dating to determine how volcanic eruption processes have evolved with the eruptive environment throughout this period.


A wide diversity in the physical volcanology of deposits and major element geochemistry indicates a rich eruptive history alongside changes in glacial configuration and meltwater availability in this area. Volcanic products include pillow lavas, pillow breccias, tuff sheets 50-100 m thick, tuff mountains containing crystal-rich intrusions, lobate lava, entablature lava and compound pahoehoe lava. Evidence for glaciofluvial processes, including debris flow deposits, diamictite, and possible flood-formed canyons demonstrate additional processes that have shaped this landscape. Recognition of volcanic, constructive processes vs remobilisation and erosive processes is vital for accurately determining the distribution and source of products, particularly since edifice morphology is commonly used to characterise glaciovolcanoes.


Reliable dating from independent sources is necessary to determine the chronology of events and the timescale of volcano evolution. Identification of the Þórsmörk ignimbrite within the stratigraphy indicates a timescale spanning > 55 ka as well as a period of ice-free conditions. Additional age constraints from deposits in the area include a 40Ar/39Ar date from basaltic lava of < 20 ka and the identification of reworked Vedde-like pumice (< 12 ka). The sequence is capped by the 2010 Fimmvörðuháls lava. We are testing the use of paleomagnetic dating to refine the dates that have higher uncertainty and to provide additional ages for intercalated lavas that cannot be dated by radiometric isotope systems.


Given the ongoing changes in global glacier extent, it is critical to understand how glaciated volcanoes will behave physically. We are building an age-constrained eruptive history and record of eruptive environment from one of the most volcanically productive areas of Iceland to inform our understanding of the influence a changing environment has on volcanism.

How to cite: Cole, R., Gudmundsson, M. T., Piispa, E., Óskarsson, B., Gallagher, C., Jicha, B., and Farnsworth, W.: Volcanic eruption styles in changing environments at Katla and Eyjafjallajökull volcanoes, south Iceland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11452,, 2024.

Arthur Jolly, Alex Iezzi, Matt Patrick, Aaron Wech, Weston Thelen, John Lyons, and Jefferson Chang

The 2022 Mauna Loa eruption began on November 27 23:21 HST (November 28 9:21 UTC) at the summit, based on the onset of seismic tremor and visual observations of nighttime incandescence from lava viewed by webcameras.  Continued visual observations noted early southwestward migration of the summit flows followed by dike propagation and new fissures on the northeast rift zone in the early hours of November 28th HST.   Northeast rift zone activity subsequently settled into persistent activity primarily from Fissure 3 (located about 7 km from the Summit) until the eruption stagnated by December 9th HST.

This contribution provides a detailed retrospective assessment of the performance of four Hawaiian Volcano Observatory (HVO) infrasound arrays (AIND, AHUD, MENE, SHEEP) and an International Monitoring System array operated by the University of Hawaii Infrasound (I59US) data during the onset and progression of the eruption.  We use results from a standard least-squares beamforming algorithm which is widely used for infrasound processing across the USGS Volcano Science Center and compare other multidisciplinary observations such as visual and seismic amplitude.

We find that that the standard array processing approach performed adequately as a real-time assessment tool with high correlation back-azimuth computations in reasonable agreement with visual observations.  High winds associated with storms impacted the quality of our results, particularly toward the end of the eruption when infrasound signals were comparably small.  It was possible to distinguish between summit and rift fissure activity using the three long-term arrays operated by HVO, despite the large source to receiver distance.  The SHEEP array (on the south flank of Mauna Kea) was established in response to the Mauna Loa eruption and only recorded the waning phase of the eruption.  Regardless, the new array should further improve azimuthal coverage for future Mauna Loa eruptive activity.

How to cite: Jolly, A., Iezzi, A., Patrick, M., Wech, A., Thelen, W., Lyons, J., and Chang, J.: Summit and rift vent progression captured by infrasound during the 2022 Mauna Loa eruption, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12280,, 2024.

Mónica Arencibia Hernández, Rosella Feraco, Siobhan O'Shea, Sttefany Cartaya, Fátima Rodríguez, Gladys V. Melián, María Asensio-Ramos, Eleazar Padrón, Nemesio M. Pérez, Pedro A. Hernández, and Germán D. Padilla

La Palma Island, spanning 708.32 km2, resides at the north-western edge of the Canary Archipelago and is among the youngest within this group. In the last 123,000 years, volcanic activity has been exclusive to Cumbre Vieja in the island's southern region. The last volcanic activity (Tajogaite eruption) took place at the west flank of Cumbre Vieja from 19 September to 13 December 2021. It was a fissure and powerful strombolian eruption with a magnitude VEI = 3 (Bonadonna et al., 2022). Due to the absence of visible geothermal manifestations, recent decades have witnessed a burgeoning interest in studying diffuse degassing as a vital tool for volcano monitoring. With the aim of strengthening the geochemical monitoring of Cumbre Vieja volcanic activity, we have conducted on a weekly basis from October 2017 to the present, two distinct studies for volcano monitoring. Firstly, we monitored physical-chemical parameters and the chemical/isotopic composition and dissolved gases in the groundwater of two galleries (Peña Horeb and Trasvase Oeste) and three water wells (Las Salinas, Charco Verde, and San Isidro) before, during, and after the Tajogaite Volcano eruption at Cumbre Vieja from September 19 to December 13, 2021. We observed significant temporal variations in pH, EC, ion content, pCO2, and δ13C-CO2, correlating with interactions between deep volcanic fluids and groundwater. These changes showed good temporal agreement with the eruption and seismic swarms leading up to it. Simultaneously, we established a network of 21 closed static chambers to measure soil CO2 effluxes. Before the eruption (October 2017 to December 2020), the recorded soil CO2 efflux averaged 7.30 g·m-2·d-1 across Cumbre Vieja (7.48, 7.35, and 7.11 g·m-2·d-1 in the north, east, and west, respectively). Post-eruption (March 2022 to present), it averaged 7.51 g·m-2·d-1 (8.09, 7.58, and 6.99 g·m-2·d-1). The absence of data during this crucial period impedes direct comparisons and assessment of volcanic activity using this specific monitoring tool.

These methods underscore an approach to bolster volcanic surveillance on La Palma Island. Our study emphasizes the importance of monitoring the chemical and isotopic composition of groundwaters linked to active volcanic systems. Such evaluations offer critical insights into magmatic gas input within aquifers, despite limitations encountered during eruptive phases, as witnessed in the case of Cumbre Vieja in 2021.

Bonadonna et al. (2022). J.  Geophys. Res: Solid Earth, 127, e2022JB025302.

How to cite: Arencibia Hernández, M., Feraco, R., O'Shea, S., Cartaya, S., Rodríguez, F., Melián, G. V., Asensio-Ramos, M., Padrón, E., Pérez, N. M., Hernández, P. A., and Padilla, G. D.: Hydrogeochemical and soil CO2 efflux weekly monitoring network for the surveillance of Cumbre Vieja volcano, La Palma, Canary Islands, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15102,, 2024.

Danilo Messina, Graziella Barberi, Valentina Bruno, Mario Mattia, Domenico Patanè, Fabrizio Pepe, Massimo Rossi, and Luciano Scarfì

We present an analysis of Global Navigation Satellite System (GNSS) and seismic data collected in the last decade in northeastern Sicily and the Aeolian Islands (Italy). During this period, La Fossa Caldera at Vulcano showed a significant phase of unrest since September 2021. Based on the analysis of GNSS time series and velocity fields, we found evidence of changes in the deformation pattern of the Peloritani area, which is located about 40 km south of Vulcano Island in northeastern Sicily. These changes occurred about seven months before the Vulcano unrest and were accompanied by an increase in seismic strain, which was released at increasingly shallower depths. This suggests a temporal correlation between the deformations detected in the Peloritani area and the volcanic activity of Vulcano Island, which was further investigated by analyzing another phase characterized by an increase in the areal variation measured at La Fossa Caldera in 2018.   This study presents a new perspective for understanding the geodynamic, volcanic, and seismic phenomena in the investigated area, with particular attention to the Vulcan unrest between September and November 2021.

How to cite: Messina, D., Barberi, G., Bruno, V., Mattia, M., Patanè, D., Pepe, F., Rossi, M., and Scarfì, L.: Relationships between geodynamics of Northern Sicily (Italy) and volcanic activity at Vulcano Island (Aeolian Islands, Sicily, Italy) from GNSS and seismic data, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16106,, 2024.

Sttefany Cartaya Arteaga, Christian Isfort, Louis-Alexandre Lobanov, Ciara Mcknight, Mónica Arencibia, María Asensio-Ramos, Fátima Rodríguez, José González-Cantero, Gladys V. Melián, Eleazar Padrón, Germán D. Padilla, Nemesio M. Pérez, and Pedro A. Hernández

Tenerife, with 2034 km2, isthe largest active volcanic island of the Canarian archipelago and boasts over 1,000 galleries used for groundwater explotation, enabling access to the aquifer at varying depths and elevations. From mid-2016 to present, we've diligently sampled two important galleries - Fuente del Valle and San Fernando - on a weekly basis for volcanic monitoring. On-site measurements of water's physicochemical parameters such as temperature (ºC), pH, and electrical conductivity (E.C., µS·cm-1) were conducted at each sampling point. Subsequently, the water's chemical/isotopic composition and dissolved gases were analyzed in the laboratory. Noteworthy trends in certain parameters, including increased conductivity, sulfate (SO42-) concentration, chloride, bicarbonate, and the SO42-/Cl- molar ratio, suggest an infiltration of deep-seated gases into the groundwater. Isotopic data further revealed a robust interaction with endogenous gases like CO2, H2S, H2, etc. Additionally, correlations were discerned between specific hydrogeochemical parameters in the gallery groundwaters, correlating with observed seismic activity changes. This study underscores the sensitivity of monitoring the chemical and isotopic composition of groundwater in Fuente del Valle and San Fernando galleries to fluctuations in volcanic activity on Tenerife. Exploring groundwater associated with a volcanic system offers insights into magmatic gas input into the aquifer, models groundwater flow within the edifice, and provides vital geochemical information potentially indicating an imminent eruption.

Concurrently, a cost-effective method to gauge CO2 fluxes using alkaline traps has significantly contributed to Tenerife's volcanic surveillance. In the summer of 2016, a network of 31 closed alkaline traps was strategically placed across Tenerife's three volcanic rifts (NE, NW, and NS) and at Cañadas Caldera, persisting until the present. The weekly replacement of alkaline solutions facilitated subsequent laboratory titration analysis of the trapped CO2, expressed as weekly integrated CO2 efflux. Across the study period, the average CO2 efflux stood at 6.41 g·m-2·d-1, with variations across regions: 8.41 g·m-2·d-1 for the NE rift-zone, 5.11 g·m-2·d-1 for Cañadas Caldera, 6.36 g·m-2·d-1 for NW rift-zone, and 6.35 g·m-2·d-1 for NS rift-zone. Notably elevated CO2 effluxes were observed in the NE rift-zone, exhibiting maximum values. While the temporal evolution of CO2 efflux estimated by closed alkaline traps exhibited minimal variation during the study, seasonal fluctuations were noted. The systematic use of closed static chamber alkaline traps proves to be a straightforward and economical method aiding volcanic surveillance, especially in areas lacking visible volcanic gas manifestations.

This comprehensive approach using chemical analysis of groundwater and CO2 flux monitoring through alkaline traps showcases their combined efficacy in advancing Tenerife's volcanic surveillance, potentially serving as a crucial precursor to future volcanic activity.

How to cite: Cartaya Arteaga, S., Isfort, C., Lobanov, L.-A., Mcknight, C., Arencibia, M., Asensio-Ramos, M., Rodríguez, F., González-Cantero, J., Melián, G. V., Padrón, E., Padilla, G. D., Pérez, N. M., and Hernández, P. A.: Groundwater and soil CO2 efflux weekly monitoring network for the volcanic surveillance of Tenerife, Canary Islands, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16290,, 2024.

Audrey Michaud-Dubuy, Mathieu Gouhier, and Yannick Guéhenneux

The prediction of the spatial and temporal evolution of ash dispersal and concentrations during an explosive volcanic eruption is crucial for crisis management. Satellite observations of volcanic ash clouds have enabled an important advance in the near-real-time quantification of the dynamic parameters of the volcanic umbrella propagating in the atmosphere. However, the link between these observations and the estimation of the eruptive source parameters (ESPs), such as the mass eruption rate (MER), remains a scientific obstacle to be overcome.

Previous studies developed methods to estimate the MER based on the temporal evolution of the volcanic umbrella obtained by visible images. The accuracy of the predictions however strongly depends on the physical model used to link the measurements made on the umbrella to the source conditions. These methods are reliable for eruptions where the impact of wind is low on the vertical plume (i.e., producing “strong plumes”), but are less suitable for weaker eruptions and/or occurring under strong wind conditions (thus producing “weak plumes”), which are much more frequent. In this study, we use the 1-D volcanic column model PPM for the estimation of ESPs based on umbrella measurements from strong to weak plumes. PPM takes into account the precise effects of wind and particle sedimentation on the plume dynamics, and has already been validated with natural data on Plinian eruptions.

The model allows predicting the plume geometry as seen from space, but close to the eruptive vent. These predictions are then used to link the MER to the umbrella geometry far from the source via an empirical factor  that connects the conditions at the neutral buoyancy height to those at the source of the umbrella cloud. The model is calibrated and tested using Meteosat-SEVIRI (MSG) images via the HOTVOLC system of paroxysms from Mt Etna (2015-2022) and from the Soufriere Saint Vincent (2021). The model allows estimating the temporal evolution of the MER during the Soufriere Saint Vincent eruption, with values consistent with those estimated in the field. The model also provides a theoretical framework to explain the geometry of weak plumes from Mt Etna. Ultimately, this study will provide a robust tool for a rapid interpretation of satellite data in terms of source conditions, which are necessary inputs for volcanic ash transport and dispersion models, such as those used by the Volcanic Ash Advisory Centers.

How to cite: Michaud-Dubuy, A., Gouhier, M., and Guéhenneux, Y.: Near real-time retrieval of weak plume source parameters: Insights from physical modeling and Meteosat data, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17989,, 2024.

Harrison Collins, Eniko Bali, and Magnus T. Gudmundsson

Paleoclimate records show that Iceland was at times fully covered during Pleistocene glaciations. Models and data for the last glacial maximum indicate that the ice sheet at this time extended several tens of kilometers beyond the present coast. In contrast, much is known about the extent of the ice sheet during other times of the Weichselian glaciation, and very little information exists on possible variations of earlier glaciations. The regions near Þórisvatn, Jökulheimar, and Bláfjöll in the south-central highland of Iceland contain many outcrops of Pleistocene pillow lavas. The volatile contents in the glassy rims of pillow lavas may record the ambient pressure during eruption. This could offer insight into syn-eruptive glacier thickness. 15 samples were collected from three sample locations near Þórisvatn, one near Jökulheimar, and four near Bláfjöll from August 14 to August 15, 2023. Samples were crushed and sieved into 0.5-2.0 mm grains, and the glassiest grains were double polished with thicknesses between 88–219 µm for FTIR analysis. The spectra showed strong similarity to FTIR spectra of Holuhraun samples of similar thickness. H2O contents of the samples varied between 0.22–0.32 wt%, with a median of 0.30 wt%. CO2 was under the detection limit of the FTIR analyses. This may be an artifact of polishing grains too thin, and thus separate analyses with thicker grains will be carried out to accurately assess ambient pressure due to pressure model sensitivity to CO2. Further analysis will include S concentrations, which will be used alongside H2O and CO2 to calculate a precise ambient pressure with the Sulfur_X model (Ding et al., 2023). The derived parameters will be used to estimate glacier thickness.

How to cite: Collins, H., Bali, E., and Gudmundsson, M. T.: Estimating Pleistocene ice thickness from pillow lava melt inclusions in the south-central highland of Iceland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18052,, 2024.

The response of microseismicity to re-inflation at Askja caldera, Iceland: new insights from a dense nodal deployment
Tom Winder, Isabel Siggers, Nick Rawlinson, Bryndís Brandsdóttir, and Robert S. White
Simone Aguiar, Laura Sandri, Adriano Pimentel, Sérgio Oliveira, and José Pacheco

Forecasting the location of future volcanic eruptions is one of the most critical and challenging issues when assessing volcanic hazard. A long-term hazard assessment approach based on past eruptive behaviour is of utmost importance for dormant or low-activity volcanoes, on which sound land-use policies and risk mitigation plans should be based.
São Miguel Island in the Azores Archipelago hosts three active central volcanoes (Sete Cidades, Fogo, and Furnas) that produced a large variety of eruptions in the last millennia and even in historical times, including trachytic explosive and effusive events and basaltic flank eruptions. 
Although these volcanoes are currently in a repose period, the likelihood of future eruptions should not be neglected.  
This study focuses on the estimation of the spatial probability of vent opening at the Sete Cidades, Fogo, and Furnas volcanoes separately, using the kernel method. Here, we used the location of past basaltic and trachytic emission centres, in the form of vents or fissures, of each volcano, to explore different kernel functions (Gaussian, Cauchy, Exponential, and Uniform) and calculate the best degree of clustering of vents given by a smoothing parameter (h). This approach was applied to each volcano by considering (1) basaltic and trachytic emission centres (fissures and/or vents) and (2) only trachytic emission centres (vents). This allowed us to estimate the pair (kernel function and h-value) that best fits the empirical cumulative distribution function of the minimum distance between emission centres and compute the final vent opening probability maps conditional to an eruption (or susceptibility maps).
For Sete Cidades, the results show that when considering basaltic and trachytic emission centres together, the southeast and west flanks of the volcano have a higher likelihood of hosting a new vent; however, when considering trachytic vents alone, the higher probability is at the west flank and southern sector of the caldera. The susceptibility map generated using Fogo’s basaltic and trachytic emission centres indicates a higher likelihood of hosting a new vent at the northwest flank of the volcano and southeast sector of the caldera. When only trachytic vents are considered, the southeastern sector of the caldera is more likely to host a new vent. For Furnas volcano, the results show that the northwestern part of the caldera has a higher likelihood of hosting a future basaltic or trachytic vent.

How to cite: Aguiar, S., Sandri, L., Pimentel, A., Oliveira, S., and Pacheco, J.: Spatial probability of vent opening at the active central volcanoes of São Miguel (Azores), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18410,, 2024.

Cantarero Massimo, De Beni Emanuela, Proietti Cristina, Bonali Fabio Luca, Palano Domenico, Civico Riccardo, and Paratore Mario

Etna is one of the most active volcanoes in the world, with almost continuous eruptive activity from its four summit craters resulting in frequent morphological variation of its upper area. The summit area is frequently site of effusive and explosive activity, but also of local flank collapses of the summit cones and pyroclastic flows with different triggering mechanisms. Such a dynamic environment requires a thorough understanding of its temporal evolution in order to properly assess the state of the volcano over time, and infer further insight into its potential hazard. Voragine (VOR), formerly called the Central Crater, is the oldest and has been depicted on topographic maps since at least 1865; the NE-Crater (NEC) cone was born in 1911; the Bocca Nuova started as a pit crater next to Voragine in 1968, and the SE-Crater (SEC) cone started in 1971. Since 2011, a new cone grew on the SEC eastern lower flank during a series of paroxysmal episodes and it progressive coalesced with the SEC cone. To properly model the temporal changes of the summit area, we exploited archival topographic maps and aerial photogrammetric stereo-pairs. This reconstruction started from the digitising and processing of topographic maps that were produced on 1897, 1932, and 1985. We also processed aerial stereo-images acquired since 1954. From these datasets we extracted Digital Elevation Models (DEMs) with 5-10 m pixel size. We integrated historical data with already available DEMs: the 1998 and 2001, interpolated from vector maps; the 2005, obtained from aerial photogrammetry; and the 2012, 2014 and 2015 derived from helicopter-acquired data. Finally, between 2017 and 2023 we performed UAS (unoccupied aerial systems) surveys to derive high-resolution DEMs and orthomosaics with sub-meter pixel size. This new multi-temporal Digital Elevation Models (DEMs), from ancient topographic maps and aerial photo as well as from recent and current UAS data, have been analysed through the ESRI ArcGIS software to reconstruct the topography and quantify the main morphological changes of Etna summit area. Our modelling increases the knowledge about the evolution and the behaviour of a frequently active volcano, thus enabling to mitigate the associated risks.


How to cite: Massimo, C., Emanuela, D. B., Cristina, P., Fabio Luca, B., Domenico, P., Riccardo, C., and Mario, P.: 150 years of Etna Summit Craters through a photogrammetry-based time machine, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19010,, 2024.

Isabel Siggers, Tom Winder, Nicholas Rawlinson, Robert S. White, and Bryndís Brandsdóttir

Askja, an active volcano in Iceland’s Northern Volcanic Zone, has experienced over 70 centimetres of uplift since August 2021, following several decades of ground surface deflation. In the same month that surface uplift began, there was also an overall increase in shallow microseismicity. This overlap suggests that there is a link between the shallow seismicity and re-inflation, but much more information is needed to constrain an exact mechanism.


To gain more insight into the stresses driving seismicity beneath Askja, and how they may have changed with the onset of uplift, moment tensor solutions were constructed from a subset of events within the Askja caldera, both before and after the start of re-inflation. The goal is to uncover any dominant earthquake slip orientation patterns, and how they have changed post August 2021. Cambridge’s Volcano Seismology Group has maintained a dense seismic network surrounding and within Askja from July 2007 to the present day, which provides sufficient data to produce well constrained moment tensor solutions, even for events as small as magnitude 0.5.


Moment tensor solutions constructed from the first year of inflation suggest that the direction of slip along faults encircling the crater lake Öskjuvatn did not change when Askja switched from deflation to re-inflation; however, data from a longer recording period is needed to provide a definitive conclusion. With another 12 months of data from the main network now downloaded, as well as additional data from a supplementary dense network of seismic nodes within the Askja caldera from July 2023 to September 2023, a more in-depth analysis of the moment tensor solutions for shallow microearthquakes underneath the region of uplift through time is now possible. The preliminary results of this analysis will be presented, along with plans for future interrogation of this enhanced dataset.

How to cite: Siggers, I., Winder, T., Rawlinson, N., White, R. S., and Brandsdóttir, B.: Earthquake focal mechanisms before and after the onset of re-inflation at Askja caldera, Iceland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19414,, 2024.

Gaetana Ganci, Giuseppe Bilotta, Alessandro Pignatelli, Simona Scollo, and Elisa Trasatti and the SAFARI team

Identifying the observable signals that warn against volcanic unrest and impending eruptions is one of the greatest challenges in the management of natural disasters. In this regard, satellite data has become a strong focus of global interest, offering abundant datasets from multi-missions and valuable tools to study Earth and improve physical models.

The SAFARI project aims at developing a comprehensive space-based strategy for next-generation quantitative volcano hazard monitoring integrating the most recent satellite imagery capabilities and the relative products with the newest technologies mainly in the field of Machine Learning (ML) and Soft Computing. The main objectives of SAFARI include: (i) following the manifestations of unrests and impending eruptions, as well as (ii) forecasting the areas potentially threatened by volcanic products through eruptive scenarios. For this purpose, SAFARI intends to characterize the state of volcanic activity (quiet, unrest and eruptive phases) by taking advantage of a variety of satellite data, including active and passive sensors ranging from optical to microwave frequencies, and to extract quantitative satellite-derived input parameters to physical models for rapid and accurate scenario forecasting during eruptions. 

Well-established products from space-based volcano monitoring such as: (i) volcanic radiative power, (ii) surface displacement and (iii) volcanic gas emission (e.g., SO2, BrO) time series are processed jointly and supported by less frequently used but still informative time series such as (iv) ground skin temperature of the volcanic edifices, (v) change detection time series, (vi) time-varying volcanic ash indices, (vii) ash top height time series, (viii) gravity field variation and also (ix) time varying indices giving information about deformation phases of the volcanic edifice (i.e., inflation/deflation) as well as (x) crucial parameters related to the volcanic source (e.g., depth, volume variation) by using data assimilation to deformation models. SAFARI merges and assembles the latest developments from different INGV teams, in a way to analyze Earth observation (EO) data with a retrospective and multi-disciplinary approach, employing traditional statistical or numerical analysis, latest generation Graphic Processing Units (GPUs) architectures and newer and more sophisticated ML algorithms to classify time series, detect anomalies, and predict or estimate significant parameter values. 

The methodologies in SAFARI are developed and verified at four active volcanoes worldwide: Etna and Vulcano (Italy), continuously monitored by dense ground based networks managed by INGV, which will provide a first controlled experiment, and Nyiragongo (D.R. Congo) and Sangay (Ecuador), characterized by high volcanic hazard but with modest permanent monitoring networks, where satellite remote sensing is a key monitoring tool.

The results of the SAFARI project and its underlying data source and methodologies, as well as the potential of the whole integrated processing chain, aim at becoming an effective tool for volcanic hazard analysis and impact quantification never used to date in volcanology, improving safety and reducing risk associated to eruptive events worldwide.

How to cite: Ganci, G., Bilotta, G., Pignatelli, A., Scollo, S., and Trasatti, E. and the SAFARI team: The SAFARI project: An Artificial Intelligence-based strategy for volcano hazard monItoring from space, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8200,, 2024.