Volcanic Hazard Mitigation Research Articles

Statistical analysis of the ground deformation of Vulcanian explosions at Sakurajima volcano, Japan

The forecast of pulsatory explosions during volcanic unrest periods is an essential issue for the assessment and mitigation of volcanic hazards. Although various precursors are detectable through geophysical and geochemical monitoring, difficulties remain in precisely constraining possible scenarios. A probabilistic approach is effective in assessing risk while considering various uncertainties. Sakurajima volcano characterized by frequent Vulcanian activity is one of the suitable fields for the probabilistic forecast of pulsatory explosions. Their inflation-deflation patterns of ground deformation related to Vulcanian explosions are useful for evaluating the imminence and size of the next event. The large database obtained from its vigorous activity can contribute to statistical analysis. In this study, aiming the probabilistic forecast of the timing and size of explosions, we investigated the duration of inflation and volume changes at the pressure source using strain records of over 5000 events of Sakurajima volcano. Then, a stochastic model was estimated to explain the distribution of these events. The log-logistic distribution was found to be an appropriate model for data distribution, indicating the presence of competing processes, such as pressurization and depressurization, in the conduit. The model parameters of the log-logistic distribution temporally fluctuated reflecting the volcanic activity, especially increasing the magma supply from a deep region. We also suggested a methodology to constrain the probabilities of the likely timing and size of an imminent explosion using real-time strain monitoring and an estimated model distribution. Although some improvements would be needed for practical forecasting, our approach could be useful in predicting possible ash hazards.

Contextual E-Comics in Geography: A Modern Pedagogical Tool for Volcanic Hazard Mitigation Awareness

Technological advancements have profoundly reshaped educational paradigms, leading to an expansive array of instructional media. Nevertheless, empirical observations reveal educators' hesitancy in assimilating these technologies, notably within geography instruction. Predominantly, geography pedagogy has gravitated towards memorization-based approaches, thereby constricting students' capacity to correlate academic content with their empirical experiences—a consequence of an entrenched reliance on conventional textbooks. Addressing this instructional void, our research endeavoured to devise an E-Comic media, underpinned by a contextual approach, to elucidate strategies for mitigating volcanic eruptions. The empirical setting for this study was situated at SMA PGRI 1 Lumajang. The research harnessed the Research and Development (R&D) methodology, employing the comprehensive ADDIE model. This model delineates five distinct phases: 1) Curricular, student demographic, and educator need analysis; 2) Storyboard conceptualisation for the impending product; 3) Product realisation in conformity with the established design; 4) Implementation, encompassing a rigorous vetting process by domain-specific expert validators and the intended research demographic. Evaluation metrics showcased robust approval ratings: 87% from media specialists, 97% from subject-matter experts, 95% from educator respondents, and 87% endorsement from student participants. In light of these affirmations, as conceptualised and developed in this study, the E-Comic medium is posited as an academically sound and pedagogically effective tool.

Volcanic monitoring of the 2021 La Palma eruption using long-period magnetotelluric data

Between September and December 2021, the first subaerial volcanic eruption in the Canary Islands in 50 years took place on the island of La Palma. Since November 2021, we have been conducting a long-period magnetotelluric (MT) monitoring experiment at a site located 2.4 km east of the volcanic cone. Having continuously recorded data since then, the obtained dataset shows significant changes in resistivity over the fourteen months following the eruption: more than ± 20% in apparent resistivity and ± 2 degrees in phase. These temporal variations in electrical resistivity, recorded continuously using long-period MT during both the syn- and post-eruptive stages, have not been reported to date, making this dataset unique. Four estimated impedances have been selected as representatives of the major temporal changes observed and inverted to generate new 3-D resistivity models. The results provide novel key information on the spatiotemporal evolution of the subsoil's electrical resistivity, enabling the characterization of a set of structures acting as preferred magmatic fluid pathways. Therefore, our study highlights the strong potential of MT as a volcanic monitoring tool and provides new insights about the evolution of the fluid pathways during the post-eruptive stage. These findings enhance our understanding of the magmatic system and may contribute to volcanic hazard mitigation in the future.

Development And Evaluation Of The Webgis Application To Support Volcanic Hazard Mitigation In The Southern Flank Of Merapi Volcano, Sleman Regency, Yogyakarta Province, Indonesia

Merapi Volcano is one of the active volcanoes in Indonesia, which is located in the Central Java and Yogyakarta Province. The eruption of Merapi Volcano is a threat to people living on the slopes of Merapi, especially on its denselypopulated southern flank. The purpose of this study was to build a webGIS to support volcanic hazard mitigation regarding Merapi Volcano and evaluate the webGIS system for determining the community’s perception. This research was the first to produce a product that is used by government agencies related to volcanic disaster mitigation. webGIS development was carried out using an open source platform. System evaluation was carried out using usability testing. The samples were obtained using systematic the random sampling method of respondents who lived in the villages on the southern flank of Merapi volcano. webGIS was built using LeafletJS and QGIS, combined with spatial data about the evacuation locations, health facilities, evacuation routes, government offices, educational facilities and worship facilities, with a basemap obtained from Openstreet Map and Google Satellite. WebGIS was equipped with a database query feature to make it easier for users to find geographical information. The usability testing results showed that as many as 83% of the respondents were very satisfied with the appearance and information of webGIS, while as many as 82% were very satisfied with the navigation offered via the webGIS display.

The Permeability of Porous Volcanic Rock Through the Brittle‐Ductile Transition

The permeability of volcanic rock controls the distribution of pore fluids and pore fluid pressure within a volcanic edifice, and is therefore considered to influence eruptive style and volcano deformation. We measured the porosity and permeability of a porous volcanic rock during deformation in the brittle and ductile regimes. In the brittle regime, permeability decreases by a factor of 2–6 up to the peak stress due the closure of narrow pore throats but, following shear fracture formation, remains approximately constant as strain is accommodated by sliding on the fracture. In the ductile regime, permeability continually decreases, by up to an order of magnitude, as a function of strain. Although compaction in the ductile regime is localized, permeability is not reduced substantially due to the tortuous and diffuse nature of the compaction bands, the geometry of which was also influenced by a pore shape preferred orientation. Although the evolution of the permeability of the studied porous volcanic rock in the brittle and ductile regimes is qualitatively similar to that for porous sedimentary rocks, the porosity sensitivity exponent of permeability in the elastic regime is higher than found previously for porous sedimentary rocks. This exponent decreases during shear‐enhanced compaction toward a value theoretically derived for granular media, suggesting that the material is effectively granulating. Indeed, cataclastic pore collapse evolves the microstructure to one that is more granular. Understanding how permeability can evolve in a volcanic edifice will improve the accuracy of models designed to assist volcano monitoring and volcanic hazard mitigation.

Self-Supervised Contrastive Learning for Volcanic Unrest Detection

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

Message from the Winner

A volcanic eruption is a phenomenon in which ballistic bombs, lapilli, volcanic ash, lava, and gas are discharged. Volcanic ash and gas are carried by the wind, and pyroclastic flows and lava flows are carried away by the force of gravity. These cause disasters of various forms in the areas around volcanoes, sometimes far from eruptive center. Accordingly, volcanic countries, particularly Asian countries such as Japan, Indonesia, and the Philippines, have been the scenes of volcanic disasters. We conducted the research project “Integrated study on mitigation of multimodal disasters caused by the ejection of volcanic products” with the Center for Volcanology and Geological Hazard Mitigation and other institutes in Indonesia under the SATREPS project from FY2013 to 2018. The aim of the project was to advance volcanic hazard mitigation, and I served as the guest editor of “Special Issue on Integrated Study on Mitigation of Multimodal Disasters Caused by Ejection of Volcanic Products” (2016) and “Special Issue on Integrated Study on Mitigation of Multimodal Disasters Caused by Ejection of Volcanic Products: Part 2” (2019) of the Journal of Disaster Research. The articles in the Special Issues have been downloaded by many researchers. The Special Issues cover many topics related to volcanic disasters, but the main theme is how to forecast real-time volcanic hazards using data monitoring, since it is this monitoring that triggers the issuing of warnings. I have studied the volcanic activity of Sakurajima, the most active volcano in Japan, for 40 years, primarily to forecast its eruptions. Forecasting the eruptions is not as important as forecasting the hazards and risks posed by volcanic actions. Research done on the mitigation of the volcanic hazards of Sakurajima as well as Indonesian volcanoes has been enhanced by interaction. The cumulative volume of magma stored in the past 100 years indicates that Sakurajima has the potential for a large-scale eruption (VEI > 4). An eruption and its dispersal of volcanic ash in particular would cause a variety of disasters over a wide area, as described in the other issues of Journal of Disaster Research. I hope that the research results will be utilized for hazard mitigation in the event of future large-scale eruptions. The research could be advanced through collaboration with studies aimed at the enhancement of resilience and recovery.

The BrIdge voLcanic LIdar—BILLI: A Review of Data Collection and Processing Techniques in the Italian Most Hazardous Volcanic Areas

Volcanologists have demonstrated that carbon dioxide (CO2) fluxes are precursors of volcanic eruptions. Controlling volcanic gases and, in particular, the CO2 flux, is technically challenging, but we can retrieve useful information from magmatic/geological process studies for the mitigation of volcanic hazards including air traffic security. Existing techniques used to probe volcanic gas fluxes have severe limitations such as the requirement of near-vent in situ measurements, which is unsafe for operators and deleterious for equipment. In order to overcome these limitations, a novel range-resolved DIAL-Lidar (Differential Absorption Light Detection and Ranging) has been developed as part of the ERC (European Research Council) Project “BRIDGE”, for sensitive, remote, and safe real-time CO2 observations. Here, we report on data collection, processing techniques, and the most significant findings of the experimental campaigns carried out at the most hazardous volcanic areas in Italy: Pozzuoli Solfatara (Phlegraen Fields), Stromboli, and Mt. Etna. The BrIdge voLcanic LIdar—BILLI has successfully obtained accurate measurements of in-plume CO2 concentration and flux. In addition, wind velocity has also been retrieved. It has been shown that the measurements of CO2 concentration performed by BILLI are comparable to those carried out by volcanologists with other standard techniques, heralding a new era in the observation of long-term volcanic gases.

A New Japan Volcanological Database

For the purpose of the development of volcanology and practical application to volcanic hazard mitigation, we are conducting a new project named the Integrated Program for Next Generation Volcano Research and Human Resources Development (INeVRH). This project consists of 4 themes focusing on observation, forecasting, countermeasures and data sharing system. Data sharing system is named the Japan Volcanological Data Network (JVDN), which will be a platform to combine observation, prediction and countermeasure data to give information for the judgement at branch nodes of event tree for volcanic crises.

Standing waves in high speed lava channels: A tool for constraining lava dynamics and eruptive parameters

Estimates of the rheological properties of lava flows are essential for understanding their emplacement and for hazard assessment. Despite being a well-known phenomenon in water hydraulics, the formation and presence of standing waves in lava channels is poorly understood. Standing waves, generally located near the vent area, have been frequently described at high speed channelized lava flows. They are interpreted as hydraulic jumps indicating a flow under supercritical conditions. Identifying standing waves therefore offers an opportunity to apply open channel hydraulic theory for supercritical flows in order to determine important eruption parameters such as discharge rate and apparent viscosity. We use the length and amplitude of standing waves to reconstruct flow dynamics from both observational data and video analysis. The geometry of these standing waves allows us to extract the physical properties of the channelized lava (velocity, discharge rate, apparent viscosity), to estimate the channel depth and constrain the flow regime. With the rapid advances in technology, scientists can deploy equipment to enable low-cost real time monitoring of these phenomena and constrain eruption discharge rate and apparent viscosity, key parameters for volcanic hazard assessment and mitigation.

Case study and event analysis for mitigation of unpredictable volcanic hazard

Volcanology is an extremely important scientific discipline. Shedding light on how and why volcanoes erupt, how eruptions can be predicted and their impact on humans and the environment is crucial to public safety, economies and businesses. Understanding volcanoes means eruptions can be anticipated and at-risk communities can be forewarned, enabling them to implement mitigation measures. Professor Tsukasa Ohba is a scientist based at the Graduate School of International Resource Studies, Akita University, Japan, and specialises in volcanology and petrology. Ohba and his team are focusing on volcanic phenomena including: phreatic eruptions (a steam-driven eruption driven by the heat from magma interacting with water); lahar (volcanic mudflow); and monogenetic basalt eruptions (which consist of a group of small monogenetic volcanoes, each of which erupts only once). The researchers are working to understand the mechanisms of these phenomena using Petrology. Petrology is one of the traditional methods in volcanology but has not been applied to disastrous eruptions before. The teams research will contribute to volcanic hazard mitigation.

Thermal evolution of the Crater Lake of Copahue Volcano with ASTER during the last quiescence period between 2000 and 2012 eruptions

Active Crater Lakes are the surface expression of volcanic activity at the top of complex magmatic-hydrothermal systems. The Volcanic and Hydrothermal System Copahue is one of the most important active systems in Argentina. It lies at the border of Argentina and Chile and is very important, since the Copahue and Caviahue towns are very close and constitute important touristic resources including a ski center. The aim of this work is to improve the temperature register of the volcano and contribute towards a better understanding of the thermal behavior of the system during the quiescence period between the 2000 and 2012 eruptions. The surface temperature of the Crater Lake was estimated by using the Normalized Emissivity Method (NEM) on 70 images acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and we combined them with field measurements in order to capture the fundamental variations of the system. The analysis allowed the identification of two different thermal periods: (i) January 2001–August 2003 and (ii) December 2004–November 2011, characterized by temperature ranges of 43–50 °C and 30–45 °C, respectively. Beyond these ranges, temperature anomalies or moments of high temperature variability occurred, which corresponded to surface expressions of volcanic activity. In August 2004, the lake froze almost completely, whereas in March 2012, peak temperatures were recorded. However, a significant drop in temperature prior to the eruption of December 22, 2012, was observed, which might constitute a characteristic feature of the system. Furthermore, the Crater Lake of Copahue volcano is classified as a lake of high activity. The observations and interpretations presented constitute a useful baseline and a significant contribution towards a better understanding of the functioning of the volcano, the mitigation of volcanic hazards and the identification of volcanic unrest.

Atom Probe Tomography Analysis of Exsolved Mineral Phases.

Element diffusion rates and temperature/pressure control a range of fundamental volcanic and metamorphic processes. Such processes are often recorded in lamellae exsolved from host mineral phases. Thus, the analysis of the orientation, size, morphology, composition and spacing of exsolution lamellae is an area of active research in the geosciences. The conventional study of these lamellae has been conducted by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and more recently with focused ion beam (FIB)-based nanotomography, yet with limited chemical information. Here, we explore the use of atom probe tomography (APT) for the nanoscale analysis of ilmenite exsolution lamellae in igneous titanomagnetite from ash deposits erupted from the active Soufrière Hills Volcano (Montserrat, British West Indies). APT allows the precise calculation of interlamellar spacings (14-29 ± 2 nm) and reveals smooth diffusion profiles with no sharp phase boundaries during the exchange of Fe and Ti/O between the exsolved lamellae and the host crystal. Our results suggest that this novel approach permits nanoscale measurements of lamellae composition and interlamellar spacing that may provide a means to estimate the lava dome temperatures necessary to model extrusion rates and lava dome failure, both of which play a key role in volcanic hazard mitigation efforts.

Volcano Monitoring from Space Using High-Cadence Planet CubeSat Images Applied to Fuego Volcano, Guatemala

Fuego volcano (Guatemala) is one of the most active and hazardous volcanoes in the world. Its persistent activity generates lava flows, pyroclastic density currents (PDCs), and lahars that threaten the surrounding areas and produce frequent morphological change. Fuego’s eruption deposits are often rapidly eroded or remobilized by heavy rains and its constant activity and inaccessible terrain makes ground-based assessment of recent eruptive deposits very challenging. Earth-orbiting satellites can provide unique observations of volcanoes during eruptive activity, when ground-based techniques may be too hazardous, and also during inter-eruptive phases, but have typically been hindered by relatively low spatial and temporal resolution. Here, we use a new source of Earth observation data for volcano monitoring: high resolution (~3 m pixel size) images acquired from a constellation of over 150 CubeSats (‘Doves’) operated by Planet Labs Inc. The Planet Labs constellation provides high spatial resolution at high cadence (<1–72 h), permitting space-based tracking of volcanic activity with unprecedented detail. We show how PlanetScope images collected before, during, and after an eruption can be applied for mapping ash clouds, PDCs, lava flows, or the analysis of morphological change. We assess the utility of the PlanetScope data as a tool for volcano monitoring and rapid deposit mapping that could assist volcanic hazard mitigation efforts in Guatemala and other active volcanic regions.

Ceboruco hazard map: part II—modeling volcanic phenomena and construction of the general hazard map

Ceboruco volcano in the western Trans-Mexican Volcanic Belt is one of the eleven most active stratovolcanoes in Mexico. Due to its recent eruptive history including a large Plinian eruption ~ 1000 years ago, the AD 1870 eruption, and recurrent recent seismic activity, it seemed highly appropriate to construct a hazard map in order to be prepared for future eruptions and their associated hazards. Ceboruco volcano eruptions are predominantly effusive; however, it also has been characterized by a great variability of eruptive styles throughout its record of activity. In fact, some eruptions comprise a significant diversity of volcanic processes, including lava flows, tephra fallout, ballistic emission, pyroclastic flows and surges, and lahars. In this work, we present (1) an integrated and simplified hazard map and (2) more detailed scenario-based hazard maps showing the areas affected by the different expected volcanic phenomena attempting to account for this great diversity of eruptive processes. The maps represent the basis to identify the main hazard zones during a future eruption and the related impacts on population and infrastructure within the area of influence of Ceboruco (~ 700 km2), as well as for undertaking subsequent vulnerability and risk analyses. The maps provide a tool to develop measures of prevention and mitigation of volcanic hazards (preparedness of the population, establishment of evacuation routes and refuges, etc.), as well as for decision-making by authorities during territorial planning (urban expansion for example). The integrated simplified hazard map can also be a tool for dissemination purposes, in order to create awareness of associated hazards derived from a possible future activity of the volcano among the public in general. This is important because in the western sector of the Trans-Mexican Volcanic Belt (and specifically in the State of Nayarit) most volcanic edifices (with the exception of Colima volcano) are closed-vent volcanoes (sealed volcanic vent vs. open-vent systems) with long repose periods (up to ~ 16,000 years for example in the case of San Juan volcano 60 km to the W), a situation that consequently and unfortunately has led to a practically nonexistent volcanic risk perception.

Role of magma mixing in the pre-eruptive dynamics of the Aeolian Islands volcanoes (Southern Tyrrhenian Sea, Italy)

We combined literature and experimental data to determine the role of magma mixing in the pre-eruptive dynamics of the Aeolian Islands volcanoes. As a first step, we systematically reviewed the evidence supporting the hypothesis of mixing-triggered eruptions in the Aeolian archipelago, providing textural, chemical, and rheological constraints. The existing data highlighted the significant role of magma mixing in many eruptions within the Aeolian archipelago. Examples include the Upper Pollara and Porri volcano eruptions at Salina, Monte Guardia, and the AD 1230 Monte Pilato eruption at Lipari, as well as the present-day activity at Stromboli. Then, we focused on Vulcano Island, chosen as a case study because it represents one of the volcanoes posing the highest risk in the Aeolian archipelago. At Vulcano Island, we highlighted the role of magma mixing in the AD 1739 and 1888–90 eruptions. Finally, we investigated mixing-to-eruption timescales for the AD 1739 eruption, performing mixing experiments, and evaluated the progressive decay of the chemical concentration variance with time. Results pointed to mixing-to-eruption timescales of the order of 29 ± 9 h and magma ascent rates ranging between 3×10−2 and 5×10−2 m s−1. We finally emphasized that the presented results may have significant implications in the context of volcanic hazard mitigation and planning of emergency activities.

SO2 emissions, plume heights and magmatic processes inferred from satellite data: The 2015 Calbuco eruptions

Quantifying time-series of sulfur dioxide (SO2) emissions during explosive eruptions provides insight into volcanic processes, assists in volcanic hazard mitigation, and permits quantification of the climatic impact of major eruptions. While volcanic SO2 is routinely detected from space during eruptions, the retrieval of plume injection height and SO2 flux time-series remains challenging. Here we present a new numerical method based on forward- and backward-trajectory analysis which enable such time-series to be determined.Using this method applied to GOME-2 satellite imagery we investigate the SO2 emissions from two sub-Plinian eruptions of Calbuco, Chile, produced in April 2015. Our results show a mean injection height of 15 km for the two eruptions, with overshooting tops reaching 20 km. We calculate a total of 0.295 ± 0.045 Tg of SO2 emitted, with 0.140 ± 0.033 Tg produced by the first eruption and 0.155 ± 0.031 Tg by the second one. Using standard models we convert plume heights to mass eruption rates (MER). Comparing gas flux and MER we discover quite different volcanic processes driving the two eruptions, with the first eruption producing an SO2 flux three times higher than the second one, while they both had similar MERs. We propose that this difference reflects different exsolved volatile contents before the onset of the two eruptions, with the first eruption richer in pre-exsolved gas than the second one. This hypothesis is supported by melt inclusion measurements of sulfur concentrations in plagioclase phenocrysts and groundmass glass of tephra samples through electron microprobe analysis. Combining the satellite and petrological analysis, we propose that the overpressure caused by the pre-exsolved volatile phase (not only SO2, but also probably H2O and CO2) may have triggered the eruption.These results demonstrate that our new methodology produces constraints on SO2 flux and plume height time-series permitting new insights into sub-surface processes using satellite SO2 data.

Parametric analysis of lava dome-collapse events and pyroclastic deposits at Shiveluch volcano, Kamchatka, using visible and infrared satellite data

For the years 2001 to 2013 of the ongoing eruption of Shiveluch volcano, a combination of different satellite remote sensing data are used to investigate the dome-collapse events and the resulting pyroclastic deposits. Shiveluch volcano in Kamchatka, Russia, is one of the world's most active dome-building volcanoes, which has produced some of the largest known historical block-and-ash flows (BAFs). Globally, quantitative data for deposits resulting from such large and long-lived dome-forming eruptions, especially like those at Shiveluch, are scarce. We use Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) thermal infrared (TIR), shortwave infrared (SWIR), and visible-near infrared (VNIR) data to analyze the dome-collapse scars and BAF deposits that were formed during eruptions and collapse events in 2001, 2004, 2005, 2007, 2009, 2010, and two events in 2013. These events produced flows with runout distances of as far as 19km from the dome, and with aerial extents of as much as 22.3km2. Over the 12years of this period of investigation, there is no trend in deposit area or runout distances of the flows through time. However, two potentially predictive features are apparent in our data set: 1) the largest dome-collapse events occurred when the dome exceeded a relative height (from dome base to top) of 500m; 2) collapses were preceded by thermal anomalies in six of the cases in which ASTER data were available, although the areal extent of these precursory thermal areas did not generally match the size of the collapse events as indicated by scar area (volumes are available for three collapse events). Linking the deposit distribution to the area, location, and temperature profiles of the dome-collapse scars provides a basis for determining similar future hazards at Shiveluch and at other dome-forming volcanoes. Because of these factors, we suggest that volcanic hazard analysis and mitigation at volcanoes with similar BAF emplacement behavior may be improved with detailed, synoptic studies, especially when it is possible to access and interpret appropriate remote sensing data in near-real time.

Petrological studies of volcanic ash from Sakurajima volcano in 2013, Southern Kyushu, Japan

Many petrological studies of volcanic rocks have attempted to better predict future volcanic activity. In this study, we examined volcanic ash samples from Showa Crater in Sakurajima, Japan, which were erupted from January to October 2013. This study was used two types of juvenile material; black vesicular volcanic rock (BVVR) and black non-vesicular volcanic rock (BNVVR) to determine the variable of magmatic processes in the magma conduit during the 2013 eruption. We divided the duration into three periods such as January to April, April to July, and July to October based on the variable tendency of SiO2 contents and volume abundance of the interstitial glasses in BVVR and BNVVR. The estimated melt compositions demonstrate that the variability of SiO2 contents and volume abundance of microcrystal in the groundmass (BVVR and BNVVR) over time were caused by micro-crystallization processes. The estimated of water contents and vesicle volume shows the influence of degassing process in the rock forming. Also, the correlation of petrological features with the number of eruptions and eruptive volumes, exhibit the variable of magma supply into conduit in each period. Consequently, careful monitoring of the petrological features of erupted materials may provide useful constraints on future eruptive activity and thereby assist in the mitigation of volcanic hazards.

Fast tracking of wind speed with a differential absorption LiDAR system: first results of an experimental campaign at Stromboli volcano

Carbon dioxide ( CO 2 ) is considered a precursor gas of volcanic eruptions by volcanologists. Monitoring the anomalous release of this parameter, we can retrieve useful information for the mitigation of volcanic hazards, such as for air traffic security. From a dataset collected during the Stromboli volcano field campaign, an assessment of the wind speed, in both horizontal and vertical paths, performing a fast tracking of this parameter was retrieved. This was determined with a newly designed shot-per-shot differential absorption LiDAR system operated in the near-infrared spectral region due to the simultaneous reconstruction of CO 2 concentrations and wind speeds, using the same sample of LiDAR returns. A correlation method was used for the wind speed retrieval in which the transport of the spatial inhomogeneities of the aerosol backscattering coefficient, along the optical path of the system, was analyzed.