Explosivity Index Research Articles

Searching for potential multi-hazard events during the last 1.5 million years of the Pleistocene epoch

Increasing attention has been paid to multi-hazards in environmental disaster studies produced during the last decade. Multi-hazard studies focus on the occurrence, interaction and effect of several natural hazards in the same region. Despite the increasing number of multi-hazard studies, few investigations have focused on global-scale multi-hazard events. With the aim of closing this gap, our study focuses on the identification of periods during the last 1.5 million years of the Pleistocene epoch, with the quasi-parallel appearance of natural hazards (e.g., asteroid impacts and large volcanic eruptions with a Volcanic Explosivity Index (VEI) of 8 and 7) amplifying their individual effects and thus causing long-term, global-scale changes. Of the seven identified potential multi-hazard events, three were considered as possible global-scale events with a longer term environmental (paleoclimatic) impact; dated to c.a., 1.4 Ma (marine isotope stage – MIS45), 1.0 Ma (MIS 27), and 100 ka (MIS 5c), respectively. Two additional periods (around 50 and 20 ka) were identified as being associated with more restricted scale multi-hazard events, which might cause a “Little Ice Age-like” climatic episode in the history of the Pleistocene Period. In addition, we present a hypothesis about the complex climatic response to a global-scale multi-hazard event consisting of a series of asteroid impacts and volcanic eruption linked to a geomagnetic polarity change, namely the Matuyama-Brunhes Boundary, which might be accompanied by global cooling and result in the final step of the Early Middle Pleistocene Transition.

The global seismographic network reveals atmospherically coupled normal modes excited by the 2022 Hunga Tonga eruption

SUMMARY The eruption of the submarine Hunga Tonga-Hunga Haʻapai (Hunga Tonga) volcano on 15 January 2022, was one of the largest volcanic explosions recorded by modern geophysical instrumentation. The eruption was notable for the broad range of atmospheric wave phenomena it generated and for their unusual coupling with the oceans and solid Earth. The event was recorded worldwide across the Global Seismographic Network (GSN) by seismometers, microbarographs and infrasound sensors. The broad-band instrumentation in the GSN allows us to make high fidelity observations of spheroidal solid Earth normal modes from this event at frequencies near 3.7 and 4.4 mHz. Similar normal mode excitations were reported following the 1991 Pinatubo (Volcanic Explosivity Index of 6) eruption and were predicted, by theory, to arise from the excitation of mesosphere-scale acoustic modes of the atmosphere coupling with the solid Earth. Here, we compare observations for the Hunga Tonga and Pinatubo eruptions and find that both strongly excited the solid Earth normal mode 0S29 (3.72 mHz). However, the mean modal amplitude was roughly 11 times larger for the 2022 Hunga Tonga eruption. Estimates of attenuation (Q) for 0S29 across the GSN from temporal modal decay give Q = 332 ± 101, which is higher than estimates of Q for this mode using earthquake data (Q = 186.9 ± 5). Two microbarographs located at regional distances (<1000 km) to the volcano provide direct observations of the fundamental acoustic mode of the atmosphere. These pressure oscillations, first observed approximately 40 min after the onset of the eruption, are in phase with the seismic Rayleigh wave excitation and are recorded only by microbarographs in proximity (<1500 km) to the eruption. We infer that excitation of fundamental atmospheric modes occurs within a limited area close to the site of the eruption, where they excite select solid Earth fundamental spheroidal modes of similar frequencies that are globally recorded and have a higher apparent Q due to the extended duration of atmospheric oscillations.

Numerical Modeling of the Ash Cloud Movement from the Catastrophic Eruption of the Sheveluch Volcano in November 1964

This paper reconstructs, for the first time, the motion dynamics of an eruptive cloud formed during the catastrophic eruption of the Sheveluch volcano in November 1964 (Volcanic Explosivity Index 4+). This became possible due to the public availability of atmospheric reanalysis data from the ERA-40 archive of the European Center for Medium-Range Weather Forecasts (ECMWF) and the development of numerical modeling of volcanic ash cloud propagation. The simulation of the eruptive cloud motion process, which was carried out using the FALL3D and PUFF models, made it possible to clarify the sequence of events of this eruption (destruction of extrusive domes in the crater and the formation of an eruptive column and pyroclastic flows), which lasted only 1 h 12 min. During the eruption, the ash cloud consisted of two parts: the main eruptive cloud that rose up to 15,000 m above sea level (a.s.l.), and the co-ignimbrite cloud that formed above the moving pyroclastic flows. The ashfall in Ust-Kamchatsk (Kamchatka) first occurred out of the eruptive cloud moving at a higher speed, then out of the co-ignimbrite cloud. In Nikolskoye (Bering Island, Commander Islands), ash fell only out of the co-ignimbrite cloud. Under the turbulent diffusion, the forefront of the main eruptive cloud rose slowly in the atmosphere and reached 16,500 m a.s.l. by 04:07 UTC on November 12. Three days after the eruption began, the eruptive cloud stretched for 3000 km over the territories of the countries of Russia, Canada, the USA, Mexico, and over both the Bering Sea and the Pacific Ocean. It is assumed that the well-known long-term decrease in the solar radiation intensity in the northern latitudes from 1963–1966, which was established according to the world remote sensing data, was associated with the spread of aerosol clouds formed not only by the Agung volcano, but those formed during the 1964 Sheveluch volcano catastrophic eruption.

Fire and Explosion Economic Losses (FEEL) Index: A new approach for quantifying economic damages due to accidents in hydrocarbon storage sites

One of the areas most affected by the occurrence of fires and explosions is the economy. These accidents lead to direct economic damages, which results in the withdrawal of capital for the reconstruction of damaged areas. In addition, there are other indirect economic losses, such as business interruption and reputational losses. The DOW Fire and Explosion Index (F&EI-DOW) is currently the most complete methodology for quantifying economic losses. Notwithstanding, the F&EI-DOW focuses on quantifying the hazardous potential of process units, and, does not provide an overall criterion for the hazardous potential of the entire industrial site with regard to: the inclusion of the so-called domino effect, the probabilistic risk assessment, the updating of existing risk analysis tools with new emerging Artificial Intelligence Techniques, and the quantification of reputation losses. For this purpose, the development of a new Fire and Explosion Economic Losses-Index (FEEL-Index) is proposed, which integrates the F&EI-DOW with new factors, such as the Damaged Area Factor, the Accident Probability Factor and the Reputation Loss Factor. With regard to the application to a case study, the total losses quantified by the overall FEEL-Index predict a value higher than the one predicted by the F&EI-DOW. The results obtained on an hydrocarbon storage case study show that the application of the FEEL-Index is relevant for increasing the risk perception, as well as providing guidance for prevention, mitigation, and risk management of accidents in process industries.

Safety risk assessment of chemical production process based on local and global objectives

The chemical industry is a high-risk industry, and accidents such as fires and explosions occur frequently. This paper proposes a safety risk assessment model for the chemical production process based on local and global objectives to reduce and prevent accidents. The local objective is to apply the Dow Fire and Explosion Index (F&EI) method to evaluate the fire and explosion risks of each unit in the chemical production process. The global objective is to assess the global safety level of the chemical production process by establishing the index system, constructing the subjective and objective comprehensive weight model, and using the matter-element extension evaluation method. At the same time, the safety assessment model was applied and verified through a case of trimellitic anhydride production. The results show the accuracy and scientific feasibility of the safety assessment model. The model can help enterprises accurately determine the focus of prevention, improve intrinsic safety, and provide a practical tool for effectively enhancing the safety production level.

An application of Systems Science in the context of Greek Environmental Education for planning interventions against volcanic hazards

Schools (amid in secondary and primary education) are installations vulnerable to all kinds of hazards. Because within the last 70 years, at least, there has not been any experience of volcanic activity in Greece, this kind of hazard is not extensively referred to, by official plans, local communities as well as teachers and pupils. In this paper and by using the systemic methodology of Systems Inquiry, the authors make an exploratory analysis of school-units located at the relatively short distances of 2 to 50 Km from volcanoes with registered “Volcanic Explosivity Index” (VEI) activity. Data regarding schools, adopted from the official database of the Greek government and Ministry of Education, have been utilized. The results indicate, regarding only the historically registered VEI activity and not the following consequences/phenomena (as for example, a tsunami), that vulnerable schools are located in Sousaki (East Corinth prefecture), Methana, Milos, Santorini, Nisyros and Kos Islands. The possible number of educational personnel, pupils and infrastructures is estimated. New approaches in the context of Greek environmental education are proposed for the presentation of these hazards in the educational personnel.

Forecasting Eruptions at Poorly Known Volcanoes Using Analogs and Multivariate Renewal Processes

AbstractForecasting future destructive eruptions from re‐awakening volcanoes remains a challenge, mainly due to a lack of previous event data. This sparks a search for similar volcanoes to provide additional information, especially those with better compiled and understood event records. However, we show that some of the most obviously geologically comparable volcanoes have differing statistical occurrence patterns. Using such matches produces large forecasting uncertainties. We created a statistical tool to identify and test the compatibility of potential analogue volcanoes based on repose‐time characteristics from world‐wide datasets. Selecting analogue volcanoes with compatible behavior for factors being forecast, such as repose time, significantly reduces forecasting uncertainties. Applying this tool to Tongariro volcano (NZ), there is a 5% probability for a Volcanic Explosivity Index (VEI) ≥ 3 explosive eruption in the next 50 years. Using pre‐historic geological records of a smaller available set of analogs, we forecast a 1% probability of a VEI ≥ 4 eruption in the next 50 years.

The electrical signature of mafic explosive eruptions at Stromboli volcano, Italy

Volcanic lightning is commonly observed in explosive volcanic eruptions of Volcanic Explosivity Index (VEI) > 2 and can be detected remotely providing real-time volcano monitoring information. However, little is known about the electrical activity accompanying the lower-magnitude spectrum of explosive eruptions, often involving mafic magmas. We narrow this gap in knowledge by presenting the electrical signature of the explosive activity (VEI ≤ 1) of Stromboli volcano (Italy) recorded by an electrostatic thunderstorm detector. The persistent eruptive activity of mild Strombolian explosions is occasionally interrupted by larger-scale major explosions and paroxysmal events.Here, we present electrical observations of three major explosions and unprecedented measurements of the 3 July 2019 paroxysm. The electrical signals of the major explosions show apparent similarities, with movements of charge and tens of electrical discharges, arising the question of whether these observations could be used to supplement the classification scheme of explosions on Stromboli. The electrical signals from the 3 July 2019 paroxysm exceed those from the major explosions in amplitude, discharge rate and complexity, showing characteristic variations during different phases of the eruption.These results show that also impulsive lower-magnitude explosions generate detectable electrical activity, which holds promise for monitoring low VEI activity at mafic volcanoes.

ANALYSIS OF EXPLOSION SEVERITY OF TEA POWDER AT DIFFERENT PARTICLE SIZE AND CONCENTRATION IN A CONFINED SPACE

Tea contains compounds rich in carbon-hydrogen bonds. When tea dust is suspended in air, across a variety of particle sizes and concentrations, in the presence of spark, it can combust, therefore presenting an explosion hazard. The explosion pressure properties of tea dust of four different dust concentrations (1000 g/m³, 1500 g/m³, 2000 g/m³ and 2500 g/m³) were conducted in a 20-L spherical explosion test vessel under five distinct particle sizes (71 µm, 125 µm, 160 µm, 180 µm and 250 µm). According to the findings, the explosion pressure characteristic is strongly related to dust concentration and particle size. Moisture content also has an effect on explosion propagation. The dried tea dust reached the maximum explosion pressure faster than undried tea dust. Among of the concentration and particle size range tested, the highest explosion pressure, 14.6 bar, was recorded at 2000 g/m³ with particle size 125 μm. The explosion index was 222 bar/s. It was shown that at higher dust concentration (≥2000 g/m3) and smaller particle sizes (≤125 μm) the explosion became more severe, whereby the flame accelerated at a higher rate and raised the explosion pressure drastically. The pressure characteristic changed as the conditions in which they occurred changed. These analyses and predictions are essential for achieving safe and optimal performance of tea manufacturing technology as well as the development of new applications.

Substantiation of the specific energy intensity of drilling as a criterion characterizing the explosive destruction of rocks on the example of the Koktaszhal

Drilling and blasting operations are one of the most important components of the mining industry. Currently, further improvement and optimization of technological processes at mining enterprises are possible mainly due to the determination and constant monitoring of the mining and technological properties of the rock mass – their drillability, explosivity and exaviability. A prospective assessment of the explosivity of rocks in the massif, which is the basis for designing and calculating the parameters of the DBO, is currently possible only using the energy parameters of technological work. The article provides information on methods for studying the strength and elastic characteristics of rocks in natural occurrence. The results of the study of the relationship between the specific energy intensity of drilling and explosive destruction of rocks are presented. The correlation between the specific energy intensity of drilling and the propagation velocity of elastic longitudinal waves is also considered. A comparative analysis is carried out between the traditional calculation of the explosive index using the results of laboratory studies on the physical and mechanical properties of the rocks of the Koktaszhal deposit and the calculation of the explosive destruction index taking into account the energy parameters of drilling. The validity of the use of the specific energy intensity of drilling as a criterion characterizing the explosive destruction of rocks in the design of drilling and blasting operations is shown.

Rapid Characterization of Large Volcanic Eruptions: Measuring the Impulse of the Hunga Tonga Ha’apai Explosion From Teleseismic Waves

AbstractMost of the largest volcanic activity in the world occurs in remote places such as deep oceans or poorly monitored oceanic island arcs. Thus, our capacity of monitoring volcanoes is limited to remote sensing and global geophysical observations. However, the rapid estimation of volcanic eruption parameters is needed for scientific understanding of the eruptive process and rapid hazard estimation. We present a method to rapidly identify large volcanic explosions, based on analysis of seismic data. With this methodology, we promptly detect the 15 January 2022 Hunga Tonga Ha’apai eruption. We then analyze the seismic waves generated by the volcanic explosion and estimate its important first‐order parameters. We further relate the parameters with the volcanic explosivity index (VEI). Our estimate of VEI ∼ 6 indicates that how the Hunga Tonga eruption is among the largest volcanic activity ever recorded with modern geophysical instrumentation and can provide new insights into the physics of large eruptions.

How big will the next eruption be?

Anticipating the size of the next volcanic eruption in long-term forecasts is a major problem in both basic and applied volcanology. In this study, we investigate the extent to which eruption size is predictable based on historical and other attribute data. Data from the Smithsonian Global Volcanism Program (GVP) Catalog is used to determine the predictability of volcanic eruption size as quantified through the reported VEI (Volcano Explosivity Index). The numerical and categorical attributes from the global volcanic catalog were classified with trained random forest and simple prediction models to make a forecast of VEI that can be tested against the most recent eruption of each volcano. We compare these results to two different baseline predictability levels by: (a) selecting randomly from the global distribution of VEIs for the most recent eruptions to calculate a cohort baseline and (b) selecting the most frequent VEI for a given population to calculate a zero-rule baseline. We found that: (1) nearly any method that incorporates prior information on a specific volcano improves the prediction accuracy of the succeeding eruption VEI by at least 10 percentage points relative to the cohort baseline case, (2) incorporating attributes beyond previous VEIs can provide better accuracy and achieve up to 30 percentage point accuracy gains, (3) total accuracy of the VEI forecasting by these methods can be up to nearly 80% and (4) the zero-rule is an effective prediction method that is modestly outperformed (~ 5 percentage point gain) by random forest methods with multiple attributes on most datasets. We find no notable preference in accuracy based on volcano type. The results quantify the importance of volcano-specific information in long-term forecasting and may help practitioners assess their expected performance when anticipating future eruption size.

THE MEASUREMENT OF POTENTIAL RISK OF FIRE AND EXPLOSION AT GAS STASION IN TO ANTICIPATE NON-MILITARY THREATS

Introduction: Gas stations (SPBU in Indonesia) have the potency for fire and explosion hazards due to the storage and distribution of flammable liquids, one of which is Pertamax. This can be a non-military threat in the dimension of public safety because if it occurs, the resulting loss could be very large in terms of material or life. This study aims to determine the risk of fire and explosion at Indonesian gas station. Methods: The risk assessment method used is the Dow's Fire and Explosion Index in a simulated case. Results: The potential for fire and explosion or the value of the Fire Explosion Index (F&EI) in the simulated case is 110,828. The exposure radius is 28,39 m and the damage factor to the Pertamax storage tank is 63%. The large area of the Exposure is 24 m2 with an area of 96 m3 of the bunker building volume. The value of the loss suffered by the company in the event of a fire and explosion in the Pertamax tank is Rp. 403.908.076,97. Conclusion: The results of the study have a risk level that is classified as Intermediate, so it is necessary to control risks such as increasing active protection and is expected to be an input in efforts to safeguard against non-military threats so as to reduce the impact of risks and losses that occur in the Pertamax storage tank.

Relationship between empirical laws of turbulent combustion of dust/air mixtures

Introduction. An array of known experimental data, mainly obtained in a standard 1 m3 chamber, is considered in the article. It allowed to identify the nature of three dependences of the turbulent combustion of dust, including the dependences of limited oxygen concentration (LOC) and explosive index Kst on the energy of ignition source Eig (on a logarithmic scale) and the dependence of Kst on the initial oxygen content in the air Cox.Empirical dependencies. The analysis showed that all considered dependences, having a relative accuracy of about 20 % can be represented as linear functions of an argument varying within the following limits: Eig varies from minimum ignition energy Emin to 10 kJ; Cox ranges from LOC to 21 % vol. According to the nature of dependence of Kst on Eig, all dusts are divided into two types. For the first type of dust, Kst does not depend on Eig. For the dust of the second type, Kst ∝ (Eig – Emin).Relationship of empirical dependencies. It is shown that the considered empirical dependences should be interrelated for the dust of the second kind. Namely, slopes Cn (n = 1, 2 or 3 as the number of the dependence) of linear functions, approximating the empirical dependences for a particular dust sample, satisfy the relationship: С2(21 vol. %) = –С1∙С3(10 kJ). Due to the absence of a dust sample, for which data on all three dependences are available, the obtained relationship was confirmed for the average values of parameters: <С2(21 vol. %)> = =–<С1>∙<С3(10 kJ)>.Discussion of the result. The satisfactory accuracy of the relationship between C1, C2 и C3 gives rise to the confidence in the objectivity and relationship of the considered empirical dependences of the turbulent combustion of dust.Conclusions. It is shown that the considered empirical dependences of the turbulent combustion of dust in a 1 m3 chamber are interrelated and the form of this relationship is identified.

Magmatic evolution and architecture of an arc-related, rhyolitic caldera complex: The late Pleistocene to Holocene Cerro Blanco volcanic complex, southern Puna, Argentina

Abstract Through the lens of bulk-rock and matrix glass geochemistry, we investigated the magmatic evolution and pre-eruptive architecture of the siliceous magma complex beneath the Cerro Blanco volcanic complex, a Crater Lake–type caldera complex in the southern Puna Plateau of the Central Andes of Argentina. The Cerro Blanco volcanic complex has been the site of two caldera-forming eruptions with volcanic explosivity index (VEI) 6+ that emplaced the ca. 54 ka Campo Piedra Pomez ignimbrite and the ca. 4.2 ka Cerro Blanco ignimbrite. As such, it is the most productive recent explosive volcano in the Central Andes. The most recent eruptions (younger than 4.2 ka) are dominantly postcaldera effusions of crystal-rich domes and associated small explosive pulses. Previous work has demonstrated that andesitic recharge of and mixing with rhyolitic magma occurred at the base of the magma complex, at ~10 km depth. New isotopic data (Sr, Nd, Pb, and O) confirm that the Cerro Blanco volcanic complex rhyolite suite is part of a regional southern Puna, arc-related ignimbrite group. The suite defines a tight group of consanguineous siliceous magmas that serves as a model for the evolution of arc-related, caldera-forming silicic magma systems in the region and elsewhere. These data indicate that the rhyolites originated through limited assimilation of and mixing with upper-crustal lithologies by regional basaltic andesite parent materials, followed by extensive fractional crystallization. Least squares models of major elements in tandem with Rayleigh fractionation models for trace elements reveal that the internal variations among the rhyolites through time can be derived by extensive fractionation of a quartz–two feldspar (granitic minimum) assemblage with limited assimilation. The rare earth element character of local volumes of melt in some samples of the Campo Piedra Pomez ignimbrite basal fallout requires significant fractionation of amphibole. The distinctive major- and trace-element characteristics of bulk rock and matrix of the Campo Piedra Pomez and Cerro Blanco tephras provide useful geochemical fingerprints to facilitate regional tephrochronology. Available data indicate that rhyolites from other neighborhood centers, such as Cueros de Purulla, share bulk chemical characteristics with the Campo Piedra Pomez ignimbrite rhyolites, but they appear to be isotopically distinct. Pre-eruptive storage and final equilibration of the rhyolitic melts were estimated from matrix glass compositions projected onto the haplogranitic system (quartz-albite-orthoclase-H2O) and using rhyolite-MELTS models. These revealed equilibration pressures between 360 and 60 MPa (~10–2 km depth) with lowest pressures in the Holocene eruptions. Model temperatures for the suite ranged from 695 to 790 °C. Integrated together, our results reveal that the Cerro Blanco volcanic complex is a steady-state (low-magmatic-flux), arc-related complex, standing in contrast to the flare-up (high-magmatic-flux) supervolcanoes that dominate the Neogene volcanic stratigraphy. The silicic magmas of the Cerro Blanco volcanic complex were derived more directly from mafic and intermediate precursors through extensive fractional crystallization, albeit with some mixing and assimilation of local basement. Geochemical models and pressure-temperature estimates indicate that significant volumes of remnant cumulates of felsic and intermediate composition should dominate the polybaric magma complex beneath the Cerro Blanco volcanic complex, which gradually shallowed through time. Evolution to the most silicic compositions and final equilibration of some of the postcaldera domes occurred during ascent and decompression at depths less than 2 km. Our work connotes an incrementally accumulated (over at least 54 k.y.), upper-crustal pluton beneath the Cerro Blanco volcanic complex between 2 and 10 km depth. The composition of this pluton is predicted to be dominantly granitic, with deeper parts being granodioritic to tonalitic. The progressive solidification and eventual contraction of the magma complex may account for the decades of deflation that has characterized Cerro Blanco. The presently active geothermal anomaly and hydrothermal springs indicate the Cerro Blanco volcanic complex remains potentially active.

Multi-objective optimisation for safe multi-floor process plant layout using the Dow’s Fire & Explosion Index

In this work, we propose a multi-objective mixed-integer linear programming (MILP) model for evaluation of safe multi-floor process plant layout using the Dow’s Fire & Explosion Index (F&EI). Two objectives are considered, namely the total monetary cost and the financial risk, and solved via the ε-constraint method. The total monetary cost consisted of the piping costs, horizontal and vertical pumping costs, land purchase cost, fixed and area-dependent floor construction cost, and the cost of protection devices. The financial risk was evaluated as the maximum probable property damage cost obtained using the F&EI evaluation procedure. The proposed model was applied to an ethylene oxide plant consisting of 7 equipment items with Pareto-optimal solutions showing that the financial risk can be greatly reduced by layout reconfiguration without the need for protection devices and their associated monetary costs. Further increase in the safety levels of the plant can then be achieved through protection device installation at a cost. These, and more information obtained, which are non-existent in previous single objective considerations, are helpful for a more informed decision making process in the planning stages of the design of chemical process plants.

Assessment of explosion risk for wood dust in a ventilation-dust separation installation, by determining the concentration of total dust in suspension inside of the installation

Most of combustible dusts present both fire and explosion hazard. Explosion may occur at certain concentrations of dust mixed with air and in the presence of an ignition source. The threat posed by this real danger was confirmed by the events that took place in economic units such as: feed factories, wood products, textile industry, steel, etc. Among the parameters of explosiveness of combustible dust, which can cause an explosion, we mention: maximum explosion pressure, lower explosion limit, explosive index, minimum ignition energy, electrical resistivity of dust, minimum ignition temperature of dust layer and cloud, particle size and concentration of dust in suspension. The current paper presents the results of determinations of combustible wood dust concentrations, performed at an important economic unit, manufacturing veneer and wood panels, at a dusting ventilation installation composed of fan, cyclone and textile filter. These determinations were made in the pipe connecting the fan and the bag filter, to assess possible danger of explosion in the pipe, by relating the measured concentration to the lower explosion limit (concentration of wood dust).

New Theory of Effusive and Explosive Volcanic Eruptions

In this study, we presented new theory of effusive and explosive of volcanic eruptions. New explanation of eruption mechanisms was done by using the Elemental Buoyancy Theory and new K-Th-U structure of Earth, developed early by author. During investigation of effusive eruptions, it was given clear answer on the question why the light chemical elements, mainly silicon and sulfur compound, currently dominate in the volcanic ashes, gases, and in the magma lavas. At investigation of explosive mechanism, we analyzed 38 strong eruptions with Volcanic Explosivity Index (VEI) more than 4+. It was shown that there is a link between the planet configurations and volcanic eruptions. It can be found that volcano eruptions occurred at the different types of planet alignments. The phenomenon does depend neither on planet mass nor on the relative positions of planets. Also the phenomenon does not depend on the distance between planets, but often eruptions were observed when the distances between planets are multiple units. Also in work, it was demonstrated that the planet alignment affects not only natural processes on the Earth, but also impact the Sun activity. Based on the comparison phenomenon on the Earth and Sun, we get new mechanism to rapidly rising up pressure under the lithospheric planes by gravity vortexes. This gravity vortex was called as terrestrial magmatic protuberances.

Volcanic ash, victims, and tsunami debris from the Late Bronze Age Thera eruption discovered at Çeşme-Bağlararası (Turkey)

The Late Bronze Age Thera eruption was one of the largest natural disasters witnessed in human history. Its impact, consequences, and timing have dominated the discourse of ancient Mediterranean studies for nearly a century. Despite the eruption's high intensity (Volcanic Explosivity Index 7; Dense Rock Equivalent of 78 to 86 km) [T. H. Druitt, F. W. McCoy, G. E. Vougioukalakis, Elements 15, 185-190 (2019)] and tsunami-generating capabilities [K. Minoura etal., Geology 28, 59-62 (2000)], few tsunami deposits are reported. In contrast, descriptions of pumice, ash, and tephra deposits are widely published. This mismatch may be an artifact of interpretive capabilities, given how rapidly tsunami sedimentology has advanced in recent years. A well-preserved volcanic ash layer and chaotic destruction horizon were identified in stratified deposits at Çeşme-Bağlararası, a western Anatolian/Aegean coastal archaeological site. To interpret these deposits, archaeological and sedimentological analysis (X-ray fluorescence spectroscopy instrumental neutron activation analysis, granulometry, micropaleontology, and radiocarbon dating) were performed. According to the results, the archaeological site was hit by a series of strong tsunamis that caused damage and erosion, leaving behind a thick layer of debris, distinguishable by its physical, biological, and chemical signature. An articulated human and dog skeleton discovered within the tsunami debris are in situ victims related to the Late Bronze Age Thera eruption event. Calibrated radiocarbon ages from well-constrained, short-lived organics from within the tsunami deposit constrain the event to no earlier than 1612 BCE. The deposit provides a time capsule that demonstrates the nature, enormity, and expansive geographic extent of this catastrophic event.

The blue suns of 1831: was the eruption of Ferdinandea, near Sicily, one of the largest volcanic climate forcing events of the nineteenth century?

Abstract. One of the largest climate forcing eruptions of the nineteenth century was, until recently, believed to have taken place at the Babuyan Claro volcano, in the Philippines, in 1831. However, a recent investigation found no reliable evidence of such an eruption, suggesting that the 1831 eruption must have taken place elsewhere. We here present our newly compiled dataset of reported observations of a blue, purple and green sun in August 1831, which we use to reconstruct the transport of a stratospheric aerosol plume from that eruption. The source of the aerosol plume is identified as the eruption of Ferdinandea, which took place about 50 km off the south-west coast of Sicily (37.1∘ N, 12.7∘ E), in July and August 1831. The modest magnitude of this eruption, assigned a volcanic explosivity index (VEI) of 3, has commonly caused it to be discounted or overlooked when identifying the likely source of the stratospheric sulfate aerosol in 1831. It is proposed, however, that convective instability in the troposphere contributed to aerosol reaching the stratosphere and that the aerosol load was enhanced by addition of a sedimentary sulfur component to the volcanic plume. Thus, one of the largest climate forcing volcanic eruptions of the nineteenth century would effectively have been hiding in plain sight, arguably “lowering the bar” for the types of eruptions capable of having a substantial climate forcing impact. Prior estimates of the mass of stratospheric sulfate aerosol responsible for the 1831 Greenland ice core sulfate deposition peaks which have assumed a source eruption at a low-latitude site will, therefore, have been overstated. The example presented in this paper serves as a useful reminder that VEI values were not intended to be reliably correlated with eruption sulfur yields unless supplemented with compositional analyses. It also underlines that eye-witness accounts of historical geophysical events should not be neglected as a source of valuable scientific data.