Thermo-barometric constraints on the Mt. Etna 2015 eruptive event

AbstractThe petrological study of volcanic products emitted during the paroxysmal events of December 2015 from the summit craters of Mount Etna allow us to constrain T-P-XH2O phase stability, crystallization conditions, and mixing processes along the main open-conduit feeding system. In this study, we discuss new geochemical, thermo-barometric data and related Rhyolite-MELTS modelling of the eruptive activity that involved the concomitant activation of all summit craters. The results, in comparison with the previous paroxysmal events of the 2011–2012, reinforce the model of a vertically extended feeding system and highlight that the activity at the New South-East Crater was fed by magma residing at a significantly shallower depth with respect to the Central Craters (CC) and North-East Crater (NEC), even if all conduits were fed by a common deep (P = 530–440 MPa) basic magmatic input. Plagioclase dissolution, resorption textures, and the Rhyolite-MELTS stability model corroborate its dependence on H2O content; thus, suggesting that further studies on the effect that flushing from fluids with different H2O/CO2 ratio are needed to understand the eruption-triggering mechanisms for high energetic strombolian paroxysmal episodes.

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Chemical-physical constraints of the 2015 eruptive activity of Mt. Etna: new insights from thermo-barometry and geochemistry of olivine-hosted melt inclusions

10.5194/egusphere-egu21-15199 ◽

2021 ◽

Author(s):

Pier Paolo Giacomoni ◽

Federico Casetta ◽

Virginia Valenti ◽

Carmelo Ferlito ◽

Gabriele Lanzafame ◽

...

Keyword(s):

Melt Inclusions ◽

New South ◽

Basalt Magma ◽

Feeding System ◽

Physical Constraints ◽

Eruptive Event ◽

North East ◽

Central Crater ◽

Mt Etna ◽

Crystallization Conditions

The concomitant activation off all four summit craters of Mt. Etna during the December 2015 eruptive event allow us to investigate the chemical-physical crystallization conditions and magma dynamics in the shallower portion of the open-conduit feeding system. In this study, we discuss new petrological, geochemical and thermo-barometric data as well as the composition of major element and volatile content (H2O, CO2, F, Cl and S) of olivine-hosted melt inclusions from the explosive and effusive products emitted during the December 2015 eruptive event.Results and rhyolite-MELTS thermodynamic modelling of mineral phase stability highlight the relatively shallow crystal equilibrium depth prior to the eruption ranging from 400-500 MPa for Central Crater and North East Crater, up to 200 MPa below the New South East Crater. The study of high-pressure and high-temperature homogenized olivine-hosted melt inclusions allowed us to identify the composition of the almost primary alkali-basalt magma (11.8 wt% MgO) containing up to 4.9 wt% and 8151 ppm of H2O and CO2 respectively. The results, together with those already reported for the previous paroxystic events of the 2011-2012 (Giacomoni et al., 2018), reinforce the model of a vertically extended feeding system and highlight that the activity at the New South East Crater was fed by a magma residing at significant shallower depth with respect to Central Craters and North East Crater, although all conduits are fed by a common deep (P = 530-440 MPa) basic magmatic refilling. Plagioclase stability model and dissolution and resorption textures confirm its dependence on H2O content, thus suggesting that further studies on the effect that flushing from fluids with different H2O/CO2 ratio are needed in order to understand the eruption triggering mechanisms of paroxystic fountaining.&#160;ReferencesGiacomoni P., Coltorti M., Mollo S., Ferlito C., Braiato M., Scarlato P. 2018. The 2011-2012 paroxysmal eruptions at Mt. Etna volcano: Insights on the vertically zoned plumbing system. JVGR 349, 370-391.

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Repeating earthquakes and ground deformation reveal the structure and triggering mechanisms of the Pernicana fault, Mt. Etna

Communications Earth & Environment ◽

10.1038/s43247-021-00188-6 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Andrea Cannata ◽

Adriana Iozzia ◽

Salvatore Alparone ◽

Alessandro Bonforte ◽

Flavio Cannavò ◽

...

Keyword(s):

Ground Deformation ◽

Mount Etna ◽

Fault System ◽

Magma Intrusion ◽

Repeating Earthquakes ◽

Low Degree ◽

Mt Etna ◽

Recurrence Intervals ◽

Triggering Mechanisms ◽

Repeating Earthquake

AbstractStructure and dynamics of fault systems can be investigated using repeating earthquakes as repeatable seismic sources, alongside ground deformation measurements. Here we utilise a dataset of repeating earthquakes which occurred between 2000 and 2019 along the transtensive Pernicana fault system on the northeast flank of Mount Etna, Italy, to investigate the fault structure, as well as the triggering mechanisms of the seismicity. By grouping the repeating earthquakes into families and integrating the seismic data with GPS measurements of ground deformation, we identify four distinct portions of the fault. Each portion shows a different behaviour in terms of seismicity, repeating earthquakes and ground deformation, which we attribute to structural differences including a segmentation of the fault plane at depth. The recurrence intervals of repeating earthquake families display a low degree of regularity which suggests an episodic triggering mechanism, such as magma intrusion, rather than displacement under a constant stress.

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Seismic and infrasound signals at Mt. Etna: Modeling the North-East crater conduit and its relation with the 2008–2009 eruption feeding system

Journal of Volcanology and Geothermal Research ◽

10.1016/j.jvolgeores.2012.12.024 ◽

2013 ◽

Vol 254 ◽

pp. 53-68 ◽

Cited By ~ 9

Author(s):

Mariangela Sciotto ◽

Andrea Cannata ◽

Stefano Gresta ◽

Eugenio Privitera ◽

Laura Spina

Keyword(s):

Feeding System ◽

North East ◽

The North ◽

Mt Etna

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Combining High- and Low-Rate Geodetic Data Analysis for Unveiling Rapid Magma Transfer Feeding a Sequence of Violent Summit Paroxysms at Etna in Late 2015

Applied Sciences ◽

10.3390/app11104630 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4630

Author(s):

Alessandro Bonforte ◽

Flavio Cannavò ◽

Salvatore Gambino ◽

Francesco Guglielmino

Keyword(s):

Ground Deformation ◽

High Rate ◽

Rate Data ◽

Scale Analysis ◽

Feeding System ◽

Magma Sources ◽

Mt Etna ◽

Multi Temporal ◽

Gnss Measurements ◽

Low Rate

We propose a multi-temporal-scale analysis of ground deformation data using both high-rate tilt and GNSS measurements and the DInSAR and daily GNSS solutions in order to investigate a sequence of four paroxysmal episodes of the Voragine crater occurring in December 2015 at Mt. Etna (Italy). The analysis aimed at inferring the magma sources feeding a sequence of very violent eruptions, in order to understand the dynamics and to image the shallow feeding system of the volcano that enabled such a rapid magma accumulation and discharge. The high-rate data allowed us to constrain the sources responsible for the fast and violent dynamics of each paroxysm, while the cumulated deformation measured by DInSAR and daily GNSS solutions, over a period of 12 days encompassing the entire eruptive sequence, also showed the deeper part of the source involved in the considered period, where magma was stored. We defined the dynamics and rates of the magma transfer, with a middle-depth storage of gas-rich magma that charges, more or less continuously, a shallower level where magma stops temporarily, accumulating pressure due to the gas exsolution. This machine-gun-like mechanism could represent a general conceptual model for similar events at Etna and at all volcanoes.

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Mammal surveys in the forests of the Carrai Plateau and Richmond Range in north-east New South Wales.

Australian Mammalogy ◽

10.1071/am94003 ◽

1994 ◽

Vol 17 (1) ◽

pp. 19

Author(s):

J. Barker ◽

D. Lunney ◽

T. Bubela

Keyword(s):

Native Species ◽

New South ◽

New South Wales ◽

North East ◽

Mammal Fauna ◽

South Wales ◽

Species Lists ◽

Fauna Composition ◽

Eucalypt Forests ◽

Open Forests

Mammal surveys were carried out on the Carrai Plateau and Richmond Range in north-east New South Wales between March 1988 and November 1989. The emphasis was placed on rainforest mammals, following the recognition by Adam ( 1987) that the species lists of mammals in the state's rainforests were incomplete and that more research was needed. The mammals were surveyed primarily by analysis of prey remains in Dog and Fox scats, collected from roads throughout the forests, and from bat trapping. The bat fauna at both the Carrai Plateau and Richmond Range is rich (1 0 species and nine species respectively, including the rare Golden-tipped Bat, Kerivoula papuensis, in the Richmond Range). Scat analysis revealed the presence of 24 native species on the Carrai Plateau, and on the Richmond Range there were 17 species, including high numbers of two pademelon species. Feral prey species are almost completely absent, although the Fox is an established predator in both areas. A sharp division was identified between the mammal faunas of closed and open forests. Differences were found also between the mammal fauna composition of the two rainforest sites, and with those of nearby eucalypt forests. The mammal fauna of New South Wales rainforests is distinct from open forests and future mammal surveys are needed to ensure an adequate level of knowledge to identify and conserve these areas.

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Deploying and operating an Absolute Quantum Gravimeter on the summit of Mount Etna volcano

10.5194/egusphere-egu21-15186 ◽

2021 ◽

Author(s):

Daniele Carbone ◽

Laura Antoni-Micollier ◽

Filippo Greco ◽

Jean Lautier-Gaud ◽

Danilo Contrafatto ◽

...

Keyword(s):

Gravity Data ◽

Volcanic Tremor ◽

Mount Etna ◽

Quality Data ◽

Etna Volcano ◽

High Quality ◽

Absolute Gravimetry ◽

Superconducting Gravimeters ◽

Mt Etna ◽

Absolute Quantum

The NEWTON-g project [1] proposes a paradigm shift in terrain gravimetry to overcome the limitations imposed by currently available instrumentation. The project targets the development of an innovative gravity imager and the field-test of the new instrumentation through the deployment at Mount Etna volcano (Italy). The gravity imager consists in an array of MEMS-based relative gravimeters anchored on an Absolute Quantum Gravimeter [2]. The Absolute Quantum Gravimeter (AQG) is an industry-grade gravimeter measuring g with laser-cooled atoms [3]. Within the NEWTON-g project, an enhanced version of the AQG (AQGB03) has been developed, which is able to produce high-quality data against strong volcanic tremor at the installation site. After reviewing the key principles of the AQG, we present the deployment of the AQGB03 at the Pizzi Deneri (PDN) Volcanological Observatory (North flank of Mt. Etna; 2800 m elevation; 2.5 km from the summit active craters), which was completed in summer 2020. We then show the demonstrated measurement performances of the AQG, in terms of sensitivity and stability. In particular, we report on a reproducible sensitivity to gravity at a level of 1 &#956;Gal, even during intense volcanic activity. We also discuss how the time series acquired by AQGB03 at PDN compares with measurements from superconducting gravimeters already installed at Mount Etna. In particular, the significant &#160;correlation with gravity data collected at sites 5 to 9 km away from PDN proves that effects due to bulk mass sources, likely related to volcanic processes, are predominant over possible local and/or instrumental artifacts. This work demonstrates the feasibility to operate a free-falling quantum gravimeter in the field, both as a transportable turn-key device and as a drift-free monitoring device, able to provide high-quality continuous measurements under harsh environmental conditions. It paves the way to a wider use of absolute gravimetry for geophysical monitoring.[1] www.newton-g.com[2] D. Carbone et al., &#8220;The NEWTON-g Gravity Imager: Toward New Paradigms for Terrain Gravimetry&#8221;, Front. Earth Sci. 8:573396 (2020)[3] V. M&#233;noret et al., "Gravity measurements below 10&#8722;9 g with a transportable absolute quantum gravimeter", Nature Scientific Reports, vol.&#160;8,&#160;12300 (2018)

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Koala conservation and habitat requirements in a timber production forest in north-east New South Wales

Conservation of Australia's Forest Fauna ◽

10.7882/fs.2004.033 ◽

2004 ◽

pp. 591-611 ◽

Cited By ~ 3

Author(s):

Andrew P. Smith

Keyword(s):

New South ◽

New South Wales ◽

Habitat Requirements ◽

Timber Production ◽

North East ◽

South Wales

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A Spectra Classification Methodology of Hyperspectral Infrared Images for Near Real-Time Estimation of the SO2 Emission Flux from Mount Etna with LARA Radiative Transfer Retrieval Model

Remote Sensing ◽

10.3390/rs12244107 ◽

2020 ◽

Vol 12 (24) ◽

pp. 4107

Author(s):

Charlotte Segonne ◽

Nathalie Huret ◽

Sébastien Payan ◽

Mathieu Gouhier ◽

Valéry Catoire

Keyword(s):

Radiative Transfer ◽

Real Time ◽

Mount Etna ◽

High Spectral Resolution ◽

Retrieval Algorithm ◽

Volcanic Plume ◽

Transfer Model ◽

So2 Emission ◽

North East ◽

Emission Fluxes

Fast and accurate quantification of gas fluxes emitted by volcanoes is essential for the risk mitigation of explosive eruption, and for the fundamental understanding of shallow eruptive processes. Sulphur dioxide (SO2), in particular, is a reliable indicator to predict upcoming eruptions, and its systemic characterization allows the rapid assessment of sudden changes in eruptive dynamics. In this regard, infrared (IR) hyperspectral imaging is a promising new technology for accurately measure SO2 fluxes day and night at a frame rate down to 1 image per second. The thermal infrared region is not very sensitive to particle scattering, which is an asset for the study of volcanic plume. A ground based infrared hyperspectral imager was deployed during the IMAGETNA campaign in 2015 and provided high spectral resolution images of the Mount Etna (Sicily, Italy) plume from the North East Crater (NEC), mainly. The LongWave InfraRed (LWIR) hyperspectral imager, hereafter name Hyper-Cam, ranges between 850–1300 cm−1 (7.7–11.8 µm). The LATMOS (Laboratoire Atmosphères Milieux Observations Spatiales) Atmospheric Retrieval Algorithm (LARA), which is used to retrieve the slant column densities (SCD) of SO2, is a robust and a complete radiative transfer model, well adapted to the inversion of ground-based remote measurements. However, the calculation time to process the raw data and retrieve the infrared spectra, which is about seven days for the retrieval of one image of SO2 SCD, remains too high to infer near real-time (NRT) SO2 emission fluxes. A spectral image classification methodology based on two parameters extracting spectral features in the O3 and SO2 emission bands was developed to create a library. The relevance is evaluated in detail through tests. From data acquisition to the generation of SO2 SCD images, this method requires only ~40 s per image, which opens the possibility to infer NRT estimation of SO2 emission fluxes from IR hyperspectral imager measurements.

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Predation of livestock by wild dogs in eastern New South Wales.

The Rangeland Journal ◽

10.1071/rj9890061 ◽

1989 ◽

Vol 11 (2) ◽

pp. 61 ◽

Cited By ~ 18

Author(s):

PJS Fleming ◽

TJ Korn

Keyword(s):

New South ◽

New South Wales ◽

Coastal Region ◽

North East ◽

The North ◽

East Region ◽

South Wales ◽

Control Programmes ◽

June July ◽

Wild Dogs

A monthly survey involving officers from eastern New South Wales Pastures Protection Boards was conducted over four years from 1982 to 1985. Information was collected on the number and type of livestock attacked within each board district, sightings of wild dogs, the number of wild dogs kiied, the method by which they were kiied and the locations at which the observations occurred. A total of 25,644 livestock animals were reported killed or wounded from four regions; the North-East Coastal Region, the North-East Tablelands Region, the Central-East Region and South-East Region. Sheep were the most commonly attacked domestic animals followed by cattle and goats. Regional differences were apparent in the type of livestock killed and seasonal patterns of predation were evident. We recommend that annual control programmes be brought forward from June/July to late April in order to precede predation peaks.

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