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  • 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
  • 04. Solid Earth::04.08. Volcanology::04.08.07. Instruments and techniques
  • Etna
  • Elsevier  (133)
  • Nature Publishing Group  (4)
  • American Chemical Society
  • American Chemical Society (ACS)
  • Molecular Diversity Preservation International
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Keywords
Publisher
Years
  • 1
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    Experimental solidification of anhydrous latitic and trachytic melts at different cooling rates: the role of nucleation kinetics (2008)
    Elsevier
    Details
    Publication Date: 2020-10-29
    Description: Two sets of cooling experiments were run at atmospheric conditions for two anhydrous starting latitic and trachytic melts: 1) five cooling rates (25, 12.5, 3, 0.5, and 0.125 °C/min) between 1300° and 800 °C, and 2) a 11 0.5 °C/min cooling rate from 1300 °C with quench temperatures at 1200°, 1100°, 1000° and 900 °C. Trachytic run-products are invariably glassy. Nucleation is also suppressed in the latitic run-products at the three highest 13 cooling rates. Conversely, in the 0.5 and 0.125 °C/min runs, latites have a crystal content of 90 vol.%. The 14 phases are: plagioclase, clinopyroxene, glass and iron-bearing oxide (in order of abundance). The variable 15 quench temperatures, investigated by coupling experiments with Pt-wire and Pt- capsule sample containers inset 2,again did not produce crystallization of trachyte, whereas latitic samples are characterized by 10 vol.% of oxides, pyroxenes and plagioclase (in order of appearance), at temperature b1000 °C. Effects of (preferential) heterogeneous nucleation on sample holders, of superheating degree, and chemical species loss during cooling are absent for both melt compositions. The difference of solidification paths between these two silicate melts can be ascribed only to their small chemical differences. In comparison with calculated equilibrium conditions all the experimental latitic and trachytic run-products revealed strong kinetic effects, interpretable in the light of the nucleation theory. The glass- forming ability (GFA) of trachyte is higher, whereas their critical cooling rate (Rc) is lower (b0.125 °C/min), in comparison to latitic melts (RcN0.5 °C/min). The experimental results carried out in this study can be applied to lava flows and domes; trachytic lavas are able to flow for longer period with respect to latitic ones in a metastable condition. Glass-rich terrestrial lavas, i.e. obsidians, can be the result of sluggish nucleation kinetics due to the relative high polymerisation of evolved silicate melts.
    Description: Published
    Description: 91-101
    Description: 2.3. TTC - Laboratori di chimica e fisica delle rocce
    Description: 3.6. Fisica del vulcanismo
    Description: JCR Journal
    Description: reserved
    Keywords: crystallization ; lava flows ; 04. Solid Earth::04.08. Volcanology::04.08.02. Experimental volcanism ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks ; 04. Solid Earth::04.08. Volcanology::04.08.07. Instruments and techniques ; 05. General::05.02. Data dissemination::05.02.02. Seismological data
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
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  • 2
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    Mechanisms for ground-surface fracturing and incipient slope failure associated with the 2001 eruption of Mt. Etna, Italy: analysis of ephemeral field data (2008)
    Elsevier
    Details
    Publication Date: 2020-11-26
    Description: During the July^August 2001 eruption of Mt. Etna development of extensional fractures/faults and grabens accompanied magma intrusion and subsequent volcanic activity. During the first days of the eruption, we performed an analysis of attitude, displacement and propagation of fractures and faults exposed on the ground surface in two sites, Torre del Filosofo and Valle del Leone, located along the same fracture system in the region surrounding the Valle del Bove depression on the eastern flank of Mt. Etna. Fractures and faults formed as the consequence of a shallow intruding dyke system that fed the several volcanic centres developed along the fracture system. The investigated sites differ in slope attitude and in geometrical relationships between fractures and slopes. In particular, the fracture system propagated parallel to the gentle slope (67‡ dip) in the Torre del Filosofo area, and perpendicular to the steep slope (V25‡ dip) in the Valle del Leone area. In the Torre del Filosofo area, slight graben subsidence and horizontal extension of the ground surface by about 3 m were recorded. In the Valle del Leone area, extensional faulting forming a larger and deeper graben with horizontal extension of the ground surface by about 10 m was recorded. For the Valle del Leone area, we assessed a downhill dip of 14‡ for the graben master fault at the structural level beneath the graben where the fault dip shallows. These results suggest that dyke intrusion at Mount Etna, and particularly in the region surrounding the Valle del Bove depression, may be at the origin of slope failure and subsequent slumps where boundary conditions, i.e. geometry of dyke, slope dip and initial shear stress, amongst others, favour incipient failures.
    Description: Published
    Description: 281-294
    Description: 1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani
    Description: 3.2. Tettonica attiva
    Description: 3.5. Geologia e storia dei sistemi vulcanici
    Description: 3.6. Fisica del vulcanismo
    Description: JCR Journal
    Description: reserved
    Keywords: dykes ; extensional fractures ; grabens ; slope failures ; 04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamics ; 04. Solid Earth::04.07. Tectonophysics::04.07.05. Stress ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics ; 04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk ; 05. General::05.02. Data dissemination::05.02.03. Volcanic eruptions
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  • 3
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    Measuring volcanic degassing of SO2 in the lower troposphere with ASTER band ratios (2010)
    Elsevier
    Details
    Publication Date: 2020-12-07
    Description: We present a new method for measuring SO2 with the data from the ASTER (Advanced Spaceborne Thermal Emission and Reflectance radiometer) orbital sensor. The method consists of adjusting the SO2 column amount until the ratios of radiance simulated on several ASTER bands match the observations. We present a sensitivity analysis for this method, and two case studies. The sensitivity analysis shows that the selected band ratios depend much less on atmospheric humidity, sulfate aerosols, surface altitude and emissivity than the raw radiances. Measurements with b25% relative precision are achieved, but only when the thermal contrast between the plume and the underlying surface is higher than 10 K. For the case studies we focused on Miyakejima and Etna, two volcanoes where SO2 is measured regularly by COSPEC or scanning DOAS. The SO2 fluxes computed from a series of ten images of Miyakejima over the period 2000–2002 is in agreement with the long term trend of measurement for this volcano. On Etna, we compared SO2 column amounts measured by ASTER with those acquired simultaneously by ground-based automated scanning DOAS. The column amounts compare quite well, providing a more rigorous validation of the method. The SO2 maps retrieved with ASTER can provide quantitative insights into the 2D structure of non-eruptive volcanic plumes, their dispersion and their progressive depletion in SO2.
    Description: R.C. was supported by a grant from F.R.I.A (Fond pour la Recherche Industrielle et Appliquée). GGS acknowledges a PhD grant funded by the project “Sviluppo di sistemi di monitoraggio” funded by Dipartimento di Protezione Civile della Regione Sicilia, INGV (Istituto Nazionale di Geofisica e Vulcanologia, sezione di Catania—Italy) and NOVAC (Network for Observation of Volcanic and Atmospheric Change) EU-funded FP6 project no. 18354. P-F. C. is research associate with FRS-FNRS and benefited from its financial support (F.4511.08).
    Description: Published
    Description: 42-54
    Description: 1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
    Description: JCR Journal
    Description: restricted
    Keywords: remote sensing, SO2, ASTER, DOAS, Etna, Miyakejima ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 4
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    Carbon dioxide degassing from Tuscany and Northern Latium (Italy) (2008)
    Elsevier
    Details
    Publication Date: 2021-01-07
    Description: The CO2 degassing process from a large area on the Tyrrhenian side of central Italy, probably related to the input into the upper crust of mantle fluids, was investigated in detail through the geochemical study of gas emissions and groundwater. Mass-balance calculations and carbon isotopes show that over 50% of the inorganic carbon in regional groundwater is derived from a deep source highlighting gas−liquid separation processes at depth. The deep carbonate−evaporite regional aquifer acts as the main CO2 reservoir and when total pressure of the reservoir fluid exceeds hydrostatic pressure, a free gas phase separates from the parent liquid and escapes toward the surface generating gas emissions which characterise the study area. The distribution of the CO2 flux anomalies and the location of high PCO2 springs and gas emissions suggest that the storage and the expulsion of the CO2 toward the atmosphere are controlled by the geological and structural setting of the shallow crust. The average CO2 flux and the total amount of CO2 discharged by the study area were computed using surface heat flow, enthalpy and CO2 molality of the liquid phase circulating in the deep carbonate−evaporite aquifer. The results show that the CO2 flux varies from 1×104 mol y−1 km−2 to 5×107 mol y−1 km−2, with an average value of 4.8×106 mol y−1 km−2, about five times higher than the value of 1×106 mol y−1 derived by Kerrick et al. [Kerrick, D.M., McKibben, M.A., Seward, T.M., Caldeira, K., 1995. Convective hydrothermal CO2 emission from high heat flow regions. Chem. Geol. 121, 285–293] as baseline for terrestrial CO2 emissions. The total CO2 discharged from the study area is 0.9×1011 mol y−1, confirming that Earth degassing from Tyrrhenian central Italy is a globally relevant carbon source
    Description: Published
    Description: 89–102
    Description: 2.4. TTC - Laboratori di geochimica dei fluidi
    Description: 4.5. Degassamento naturale
    Description: JCR Journal
    Description: reserved
    Keywords: Earth degassing ; carbon dioxide ; CO2 flux ; groundwater ; 04. Solid Earth::04.02. Exploration geophysics::04.02.01. Geochemical exploration ; 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
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  • 5
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    Carbon dioxide degassing and thermal energy release in the Monte Amiata volcanic-geothermal area (Italy) (2010)
    Elsevier
    Details
    Publication Date: 2021-01-07
    Description: The quaternary volcanic complex of Mount Amiata is located in southern Tuscany (Italy) and represents the most recent manifestation of the Tuscan Magmatic Province. The region is characterised by a large thermal anomaly and by the presence of numerous CO2-rich gas emissions and geothermal features, mainly located at the periphery of the volcanic complex. Two geothermal systems are located, at increasing depths, in the carbonate and metamorphic formations beneath the volcanic complex. The shallow volcanic aquifer is separated from the deep geothermal systems by a low permeability unit (Ligurian Unit). A measured CO2 discharge through soils of 1.8 109 mol a 1 shows that large amounts of CO2 move from the deep reservoir to the surface. A large range in d13CTDIC ( 21.07 to +3.65) characterises the waters circulating in the aquifers of the region and the mass and isotopic balance of TDIC allows distinguishing a discharge of 0.3 109 mol a 1 of deeply sourced CO2 in spring waters. The total natural CO2 discharge (2.1 109 mol a 1) is slightly less than minimum CO2 output estimated by an indirect method (2.8 109 mol a 1), but present-day release of 5.8 109 mol a 1 CO2 from deep geothermal wells may have reduced natural CO2 discharge. The heat transported by groundwater, computed considering the increase in temperature from the infiltration area to the discharge from springs, is of the same order of magnitude, or higher, than the regional conductive heat flow (〉200 mWm 2) and reaches extremely high values (up to 2700mWm 2) in the north-eastern part of the study area. Heat transfer occurs mainly by conductive heating in the volcanic aquifer and by uprising gas and vapor along fault zones and in those areas where low permeability cover is lacking. The comparison of CO2 flux, heat flow and geological setting shows that near surface geology and hydrogeological setting play a central role in determining CO2 degassing and heat transfer patterns.
    Description: Published
    Description: 860–875
    Description: 1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
    Description: 2.4. TTC - Laboratori di geochimica dei fluidi
    Description: 4.5. Studi sul degassamento naturale e sui gas petroliferi
    Description: JCR Journal
    Description: reserved
    Keywords: Carbon dioxide degassing ; Monte Amiata ; 03. Hydrosphere::03.04. Chemical and biological::03.04.05. Gases ; 03. Hydrosphere::03.04. Chemical and biological::03.04.06. Hydrothermal systems ; 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
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  • 6
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    Evidence for an unknown explosive eruption of Mt. Etna volcano (Italy) during the Late Glacial (2021)
    Elsevier
    Details
    Publication Date: 2021-05-12
    Description: We report on the geochemical and chronological characterization of a tephra layer, here called RdV-T1, recovered within a continental sequence at Riparo di Venere site in the Fucino Basin (central Italy). Textural, mineralogical, and detailed geochemical (major and trace elements on single glass shard) analyses indicate thatMt. Etna is the volcanic source. Radiocarbon dating of charred materials above and belowthis tephra layer result in 13,380±40 (16,260–15,920 cal yrs BP) and 13,620±40 (16,625–16,230 cal yrs BP) 14C years BP, respectively. This age points out that RdV-T1 tephra derives fromthe Late Pleistocene activity of the Ellittico caldera-forming phase of Mt. Etna that is significantly (up to 1750 yrs) younger than the Biancavilla Ignimbrites and upper Acireale fall, which are the last known events of this eruptive cycle. In addition, the RdV-T1 tephra geochemical signature is distinctwith respect to the Biancavilla Ignimbrites and upper Acireale fall. Therefore, the radiocarbon and geochemical data consistently indicate that the RdV-T1 tephra may represent an explosive event following the Biancavilla Ignimbritesand the upper Acireale fall not yet identified.
    Description: Published
    Description: 106992
    Description: 1V. Storia eruttiva
    Description: JCR Journal
    Keywords: Etna ; Tephra ; Late Glacial
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  • 7
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    Tracing thermal aquifers of El Chichón volcano-hydrothermal system (México) with 87Sr/86Sr, Ca/Sr and REE (2011)
    Elsevier
    Details
    Publication Date: 2020-11-26
    Description: The volcano–hydrothermal system of El Chichón volcano, Chiapas, Mexico, is characterized by numerous thermal manifestations including an acid lake, steam vents and boiling springs in the crater and acid and neutral hot springs and steaming ground on the flanks. Previous research on major element chemistry reveals that thermal waters of El Chichón can be divided in two groups: (1) neutral waters discharging in the crater and southern slopes of the volcano with chloride content ranging from 1500 to 2200 mg/l and (2) acid-toneutral waters with Cl up to 12,000 mg/l discharging at the western slopes. Our work supports the concept that each group of waters is derived from a separate aquifer (Aq. 1 and Aq. 2). In this study we apply Sr isotopes, Ca/Sr ratios and REE abundances along with the major and trace element water chemistry in order to discriminate and characterize these two aquifers. Waters derived from Aq. 1 are characterized by 87Sr/86Sr ratios ranging from 0.70407 to 0.70419, while Sr concentrations range from 0.1 to 4 mg/l and Ca/Sr weight ratios from 90 to 180, close to average values for the erupted rocks. Waters derived from Aq. 2 have 87Sr/86Sr between 0.70531 and 0.70542, high Sr concentrations up to 80 mg/l, and Ca/Sr ratio of 17–28. Aquifer 1 is most probably shallow, composed of volcanic rocks and situated beneath the crater, within the volcano edifice. Aquifer 2 may be situated at greater depth in sedimentary rocks and by some way connected to the regional oil-gas field brines. The relative water output (l/s) from both aquifers can be estimated as Aq. 1/Aq. 2– 30. Both aquifers are not distinguishable by their REE patterns. The total concentration of REE, however, strongly depends on the acidity. All neutral waters including high-salinity waters from Aq. 2 have very low total REE concentrations (b0.6 μg/l) and are characterized by a depletion in LREE relative to El Chichón volcanic rock, while acid waters from the crater lake (Aq. 1) and acid AS springs (Aq. 2) have parallel profile with total REE concentration from 9 to 98 μg/l. The highest REE concentration (207 μg/l) is observed in slightly acid shallow cold Ca-SO4 ground waters draining fresh and old pyroclastic deposits rich in magmatic anhydrite. It is suggested that the main mechanism controlling the concentration of REE in waters of El Chichón is the acidity. As low pH results from the shallow oxidation of H2S contained in hydrothermal vapors, REE distribution in thermal waters reflects the dissolution of volcanic rocks close to the surface or lake sediments as is the case for the crater lake.
    Description: -
    Description: Published
    Description: 55-66
    Description: 1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
    Description: JCR Journal
    Description: reserved
    Keywords: hydrogeochemistry ; geothermal systems ; Sr isotopes ; REE ; El Chichón Volcano ; 03. Hydrosphere::03.02. Hydrology::03.02.03. Groundwater processes ; 03. Hydrosphere::03.04. Chemical and biological::03.04.03. Chemistry of waters ; 03. Hydrosphere::03.04. Chemical and biological::03.04.05. Gases ; 03. Hydrosphere::03.04. Chemical and biological::03.04.06. Hydrothermal systems ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
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  • 8
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    Understanding stress and deformation in active volcanoes (2010)
    Elsevier
    Details
    Publication Date: 2021-06-15
    Description: No eruption, no caldera collapse, and no landslide can take place in a volcano unless its state of stress is suitable for the associated type of rock failure. The state of stress, in turn, results in deformation, and both stress and deformation depend on the mechanical properties of the rocks that constitute the volcano. Understanding stress and deformation in volcanoes is thus of fundamental importance for understanding unrest periods and for accurate forecasting volcano failure, such as may result in large-scale lateral and vertical collapses and eruptions.
    Description: Published
    Description: 1-3
    Description: 2.3. TTC - Laboratori di chimica e fisica delle rocce
    Description: JCR Journal
    Description: reserved
    Keywords: stress, deformation, volcano tectonics, physical propertie of volcanic rocks ; 04. Solid Earth::04.07. Tectonophysics::04.07.05. Stress ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk ; 05. General::05.02. Data dissemination::05.02.03. Volcanic eruptions
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  • 9
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    Dynamics of magma ascent and fragmentation in trachytic versus rhyolitic eruptions (2005)
    Elsevier
    Details
    Publication Date: 2020-10-29
    Description: We have performed a parametric study on the dynamics of trachytic (alkaline) versus rhyolitic (calc-alkaline) eruptions by employing a steady, isothermal, multiphase non-equilibrium model of conduit flow and fragmentation. The employed compositions correspond to a typical rhyolite and to trachytic liquids from Phlegrean Fields eruptions, for which detailed viscosity measurements have been performed. The investigated conditions include conduit diameters in the range 30–90 m and total water contents from 2 to 6 wt%, corresponding to mass flow rates in the range 106–108 kg/s. The numerical results show that rhyolites fragment deep in the conduit and at a gas volume fraction ranging from 0.64 to 0.76, while for trachytes fragmentation is found to occur at much shallower levels and higher vesicularities (0.81–0.85). An unexpected result is that low-viscosity trachytes can be associated with lower mass flow rates with respect to more viscous rhyolites. This is due to the non-linear combined effects of viscosity and water solubility affecting the whole eruption dynamics. The lower viscosity of trachytes, together with higher water solubility, results in delayed fragmentation, or in a longer bubbly flow region within the conduit where viscous forces are dominant. Therefore, the total dissipation due to viscous forces can be higher for the less viscous trachytic magma, depending on the specific conditions and trachytic composition employed. The fragmentation conditions determined through the simulations agree with measured vesicularities in natural pumice clasts of both magma compositions. In fact, vesicularities average 0.80 in pumice from alkaline eruptions at Phlegrean Fields, while they tend to be lower in most calc-alkaline pumices. The results of numerical simulations suggest that higher vesicularities in alkaline products are related to delayed fragmentation of magmas with this composition. Despite large differences in the distribution of flow variables which occur in the deep conduit region and at fragmentation, the flow dynamics of rhyolites and trachytes in the upper conduit and at the vent can be very similar, at equal conduit size and total water content. This is consistent with similar phenomenologies of eruptions associated with the two magma types.
    Description: Published
    Description: 93-108
    Description: partially_open
    Keywords: trachytic magma ; conduit flow ; eruption dynamics and numerical simulations ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.07. Instruments and techniques ; 05. General::05.02. Data dissemination::05.02.03. Volcanic eruptions
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 10
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    On deformation sources in volcanic areas: Modeling the Campi Flegrei (Italy) 1982–84 unrest (2011)
    Elsevier
    Details
    Publication Date: 2020-10-13
    Description: Deformation sources in volcanic areas are generally modeled in terms of pressurized tri-axial ellipsoids or pressurized cracks with simple geometrical shapes, embedded in a homogeneous half-space. However, the assumption of a particular source mechanism and the neglect of medium heterogeneities bias significantly the estimate of source parameters. A more general approach describes the deformation source in terms of a suitable moment tensor. Ratios between moment tensor eigenvalues are shown to provide a strong diagnostic tool for the physical interpretation of the deformation source and medium heterogeneities may be accounted for through 3D finite element computations. Leveling and EDM data, collected during the 1982–84 unrest episode at Campi Flegrei (Italy), are employed to retrieve the complete moment tensor according to a Bayesian inversion procedure, considering the heterogeneous elastic structure of the volcanic area. Best fitting moment tensors are found to be incompatible with any pressurized ellipsoid or crack. Taking into account the deflation of a deeper magma reservoir, which accompanies the inflation of a shallower source, data fit improves considerably but the retrieved moment tensor of the shallow source is found to be incompatible with pressurized ellipsoids, still. Looking for alternative physical models of the dislocation source, we find that the best fit moment tensor can be best interpreted in terms of a mixed mode (shear and tensile) dislocation at 5.5 km depth, striking EW and dipping by ~25°–30° to the North. Gravity changes are found to be compatible with the intrusion of ~60–70·10^6 m^3 of volatile rich magma with density ~2400 kg/m^3.
    Description: Published
    Description: 175-185
    Description: 3.6. Fisica del vulcanismo
    Description: JCR Journal
    Description: reserved
    Keywords: volcanic source ; unrest ; finite element ; inverse theory ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
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