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  • 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring  (114)
  • 04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology  (35)
  • Elsevier  (95)
  • American Geophysical Union  (46)
  • Blackwell Publishing Ltd
  • Institute of Physics
  • Nature Publishing Group
  • 2005-2009  (141)
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  • 1
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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
    Publikationsdatum: 2020-11-26
    Beschreibung: 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.
    Beschreibung: Published
    Beschreibung: 281-294
    Beschreibung: 1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani
    Beschreibung: 3.2. Tettonica attiva
    Beschreibung: 3.5. Geologia e storia dei sistemi vulcanici
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): 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
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 2
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    Carbon dioxide degassing from Tuscany and Northern Latium (Italy) (2008)
    Elsevier
    Details
    Publikationsdatum: 2021-01-07
    Beschreibung: 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
    Beschreibung: Published
    Beschreibung: 89–102
    Beschreibung: 2.4. TTC - Laboratori di geochimica dei fluidi
    Beschreibung: 4.5. Degassamento naturale
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): 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
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 3
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    Tectonic control on the eruptive dynamics at Mt. Etna Volcano (Sicily) during the 2001 and 2002–2003 eruptions (2005)
    Elsevier
    Details
    Publikationsdatum: 2020-12-15
    Beschreibung: The eruptive events of the July–August 2001 and October 2002–January 2003 at Mt. Etna provide new insights for reconstructing the complex geometry of the feeding system and their relationship to regional tectonics. The 2001 eruption took place mainly on the upper southern sector of the volcano. The eruption was preceded by a large earthquake swarm for a few days before its onset and accompanied by ground deformation and fracturing. The development of surface cracking along with the seismic pattern has allowed us to recognize three distinct eruptive systems (the SW–NE, NNW–SSE and N–S systems) which have been simultaneously active. Such eruptive systems are only the upper portions of a complex feeding system that was fed at the same time by two distinct magmas. The SW–NE and NNW–SSE systems, connected with the SE crater conduit, were fed by magma coming from depth, whereas the N–S system served instead as an ascending pathway for an amphibole-bearing magma residing in a shallow reservoir. The eruptive activity started again on October 2002 on the NE Rift Zone, where about 20 eruptive vents were aligned between 2500 and 1900 m a.s.l., and on the southern flank, from the central crater to the Montagnola. The onset of eruptive activity was accompanied by a seismic swarm. As in the 2001 eruptive event, two independent feeding systems formed, characterized by distinct magmas. The SW–NE system controlled the feeding of the Northeast Rift and was accommodated by left-lateral displacement along the WNW–ESE trending Pernicana Fault. The N–S system fed the eruptions on the southern flank. Moreover, the associated crustal deformation triggered seismic reactivation of tectonic structures in the eastern flank of the volcano and offshore. These two last eruptions indicate that at Mt. Etna the ascent of magma, as well as the accommodation of deformation, is strongly dominated by local extensional structures that are connected to a regional tectonic regime.
    Beschreibung: Published
    Beschreibung: 211-233
    Beschreibung: partially_open
    Schlagwort(e): extensional tectonics ; volcanic activity ; seismicity ; Sicily ; Mt. Etna ; 04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Format: 520 bytes
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  • 4
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    Investigation into magma degassing at Nyiragongo volcano, Democratic Republic of the Congo (2008)
    American Geophysical Union
    Details
    Publikationsdatum: 2021-01-27
    Beschreibung: We report the first combined measurements of the composition and flux of gas emitted from Nyiragongo volcano by ground-based remote-sensing techniques. Ultraviolet spectroscopic measurements made in May/June 2005 and January 2006 indicate average SO2 emission rates of 38 kg s−1 and 23 kg s−1, respectively. Open-path Fourier transform infrared spectroscopic measurements obtained in May/June 2005, January 2006, and June 2007 indicate average molar proportions of 70, 24, 4.6, 0.87, 0.26, 0.11, and 0.0016% for H2O, CO2, SO2, CO, HCl, HF, and OCS, respectively. The composition of the plume was remarkably similar in 2005, 2006, and 2007, with little temporal variation in proportions of CO2, SO2, and CO, in particular, on the scale of seconds or days or even between the three field campaigns that span a period of 24 months. This stability persisted despite a wide range of degassing behaviors on the surface of the summit crater's lava lake (including discrete strombolian bursts and lava fountains) and variations in the SO2 emission rate. We explain these observations by a regime of steady state degassing in which bubbles nucleate and ascend in chemical equilibrium with the convecting magma. Short-term (seconds to minutes) temporal fluctuations in the SO2–HCl–HF composition were observed, and these are attributed to shallow degassing processes.
    Beschreibung: Published
    Beschreibung: Q02017
    Beschreibung: 1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Nyiragongo ; volcanic gas emissions ; FTIR ; DOAS ; remote sensing ; spectroscopy ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 5
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    Chemical evolution of thermal waters and changes in the hydrothermal system of Papandayan volcano (West Java, Indonesia) after the November 2002 eruption (2008)
    Elsevier
    Details
    Publikationsdatum: 2021-05-17
    Beschreibung: Papandayan is a stratovolcano situated in West Java, Indonesia. Since the last magmatic eruption in 1772,only few hydrothermal explosions have occurred. An explosive eruption occurred in November 2002 and ejected ash and altered rocks. The altered rocks show that an advanced argillic alteration took place in the hydrothermal system by interaction between acid fluids and rocks. Four zones of alteration have been defined and are limited in extension and shape along faults or across permeable structures at different levels beneath the active crater of the volcano. At the present time, the activity is centered in the northeast crater with discharge of low temperature fumaroles and acid hot springs. Two types of acid fluids are emitted in the crater of Papandayan volcano: (1) acid sulfate-chloride waters with pH between 1.6 and 4.6 and (2) acid sulfate waters with pH between 1.2 and 2.5. The water samples collected after the eruption on January 2003 reveal an increase in the SO4/Cl and Mg/Cl ratios. This evolution is likely explained by an increase in the neutralization of acid fluids and tends to show that water–rock interactions were more significant after the eruption. The evolution in the chemistry observed since 2003 is the consequence of the opening of new fractures at depth where unaltered (or less altered) volcanic rocks were in contact with the ascending acid waters. The high δ34S values (9–17‰) observed in acid sulfatechloride waters before the November 2002 eruption suggest that a significant fraction of dissolved sulfates was formed by the disproportionation of magmatic SO2. On the other hand, the low δ34S (−0.3–7‰) observed in hot spring waters sampled after the eruption suggest that the hydrothermal contribution (i.e. the surficial oxidation of hydrogen sulfide) has increased.
    Beschreibung: Published
    Beschreibung: 276-286
    Beschreibung: 1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
    Beschreibung: 2.4. TTC - Laboratori di geochimica dei fluidi
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Papandayan volcano ; Indonesia ; phreatic eruption ; hydrothermal system ; fluid geochemistry ; advanced argillic alteration ; gas geochemistry ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 05. General::05.02. Data dissemination::05.02.01. Geochemical data ; 05. General::05.02. Data dissemination::05.02.03. Volcanic eruptions
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 6
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    Magma-derived gas influx and water-rock interactions in the volcanic aquifer of Mt. Vesuvius, Italy (2005)
    Elsevier
    Details
    Publikationsdatum: 2021-06-25
    Beschreibung: We report in this paper a systematic investigation of the chemical and isotopic composition of groundwaters flowing in the volcanic aquifer of Mt. Vesuvius during its current phase of dormancy, including the first data on dissolved helium isotope composition and tritium content. The relevant results on dissolved He and C presented in this paper reveal that an extensive interaction between rising magmatic volatiles and groundwaters currently takes place at Vesuvius. Vesuvius groundwaters are dilute (mean TDS 2800 mg/L) hypothermal fluids (mean T 17.7°C) with a prevalent alkaline-bicarbonate composition. Calcium-bicarbonate groundwaters normally occur on the surrounding Campanian Plain, likely recharged from the Apennines. D and 18O data evidence an essentially meteoric origin of Vesuvius groundwaters, the contribution from either Tyrrhenian seawater or 18O-enriched thermal water appearing to be small or negligible. However, the dissolution of CO2-rich gases at depth promotes acid alteration and isochemical leaching of the permeable volcanic rocks, which explains the generally low pH and high total carbon content of waters. Attainment of chemical equilibrium between the rock and the weathering solutions is prevented by commonly low temperature (10 to 28°C) and acid-reducing conditions. The chemical and isotope (C and He) composition of dissolved gases highlights the magmatic origin of the gas phase feeding the aquifer. We show that although the pristine magmatic composition may vary upon gas ascent because of either dilution by a soil-atmospheric component or fractionation processes during interaction with the aquifer, both 13C/12C and 3He/4He measurements indicate the contribution of a magmatic component with a 13C 0‰ and R/Ra of 2.7, which is consistent with data from Vesuvius fumaroles and phenocryst melt inclusions in olivine phenocrysts. A main control of tectonics on gas ascent is revealed by data presented in this paper. For example, two areas of high CO2 release and enhanced rock leaching are recognized on the western (Torre del Greco) and southwestern (Torre Annunziata–Pompeii) flanks of Vesuvius, where important NE-SW and NW-SE tectonic structures are recognized. In contrast, waters flowing through the northern sector of the volcano are generally colder, less saline, and CO2 depleted, despite in some cases containing significant concentrations of magmaderived helium. The remarkable differences among the various sectors of the volcano are reconciled in a geochemical interpretative model, which is consistent with recent structural and geophysical evidences on the structure of Somma-Vesuvius volcanic complex.
    Beschreibung: -European Union, -Ministero dell’Universita’ e della Ricerca Scientifica e Tecnologica; -CNR–Gruppo Nazionale per la Vulcanologia.
    Beschreibung: Published
    Beschreibung: 963–981
    Beschreibung: partially_open
    Schlagwort(e): isotopes ; water chemistry ; dissolved gases ; 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 ; 03. Hydrosphere::03.04. Chemical and biological::03.04.07. Radioactivity and isotopes ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Format: 1032453 bytes
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  • 7
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    Seismic Tomography Experiment at Italy's Stromboli Volcano (2008)
    American Geophysical Union
    Details
    Publikationsdatum: 2021-07-14
    Beschreibung: From 25 November to 2 December 2006, the first active seismic tomography experiment at Stromboli volcano was carried out with the cooperation of four Italian research institutions. Researchers on board the R/V Urania of the Italian National Council of Research (CNR), which was equipped with a battery of four 210- cubic- inch generated injection air guns (GI guns), fired more than 1500 offshore shots along profiles and rings around the volcano.
    Beschreibung: DPC/INGV agreement 2004-2006
    Beschreibung: Published
    Beschreibung: 269-270
    Beschreibung: 1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attive
    Beschreibung: 1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: N/A or not JCR
    Beschreibung: reserved
    Schlagwort(e): Stromboli ; seismic tomography ; air-gun ; 04. Solid Earth::04.06. Seismology::04.06.07. Tomography and anisotropy ; 04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology ; 04. Solid Earth::04.06. Seismology::04.06.10. Instruments and techniques ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 8
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    Geochemical monitoring of groundwaters (1998-2001) at Vesuvius volcano (Italy) (2005)
    Elsevier
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: This work presents the results of hydrogeochemical studies carried out at Vesuvius during the period May 1998 - December 2001, mostly focusing on compositional time variations observed during this time. Based on their chemistry, groundwater samples are distinguished into two groups, 1 and 2, representative of water circulation in the southern and northern sectors of the volcano, respectively. Waters from group 1 are typically more acidic, warmer,and more saline than those of group 2. They also have higher CO2 and CH4 contents, attributed to enhanced input of deep-rising volatiles and prolonged water-rock interactions. Time-series highlight the fairly constant chemical composition of the entire aquifer. Groundwater temperature, pH, bicarbonate content and dissolved CO2 display quite stable values in the study period, particularly in deep wells (piezometric level more than 100 m deep). Shallower water bodies present more evident temporal variations, related to seasonal and anthropogenic effects. This paper also describes some important variations in water chemistry which had occurred by the time of the seismic event in early October 1999, particularly in the Olivella spring located on the northern flank of the volcano. At this site, a great decrease in water pH and redox potential, and increased dissolved CO2 contents and 3He/4He ratios were observed. These changes in chemical and isotope composition support the hypothesis of an input of magma-derived helium and carbon dioxide into the aquifer feeding the Olivella spring by the time of the earthquake.
    Beschreibung: Published
    Beschreibung: 81-104
    Beschreibung: partially_open
    Schlagwort(e): Vesuvius ; volcanic surveillance ; groundwater ; hydro-geochemistry ; oxygen-18 ; 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::04.08.06. Volcano monitoring
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Format: 1457387 bytes
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  • 9
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    Magmatic gas leakage at Mount Etna (Sicily, Italy): relationships with the volcano-tectonic structures, the hydrological pattern and the eruptive activity (2005)
    American Geophysical Union
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: In this paper we provide a review of chemical and isotopic data gathered over the last three decades on Etna volcano's fluid emissions and we present a synthetic framework of their spatial and temporal relationships with the volcano-tectonic structures, groundwater circulation and eruptive activity. We show that the chemistry, intensity and spatial distribution of gas exhalations are strongly controlled by the main volcano-tectonic fault systems. The emission of mantle-derived magmatic volatiles, supplied by deep to shallow degassing of alkali-hawaiitic basalts, persistently occurs through the central conduits, producing a huge volcanic plume. The magmatic derivation of the hot gases is verified by their He, C and S isotopic ratios. Colder but widespread emanations of magma-derived CO2 and He also occur through the flanks of the volcano and through aquifers, mainly concentrated within two sectors of the south-southwest (Paternò-Belpasso) and eastern (Zafferana) flanks. In these two peripheral areas, characterized by intense local seismicity and gravity highs, magma-derived CO2 and helium are variably diluted by shallower crustal-derived fluids (organically-derived carbon, radiogenic helium). Thermal and geochemical anomalies recorded in groundwaters and soil gases within these two areas prior to the 1991-1993 eruption are consistent with an input of hot fluids released by ascending magma. Magmatic fluids interacted with the shallow aquifers, modifying their physico-chemical conditions, and led to strong variations of the soil CO2 flux. In addition to routine survey of the crater plume emissions, geochemical monitoring of remote soil gases and groundwaters may thus contribute to forecasting Etna's eruptions.
    Beschreibung: Published
    Beschreibung: 129-145
    Beschreibung: partially_open
    Schlagwort(e): Mt. Etna ; Geochemical surveillance ; Groundwaters ; Volcanic gases ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 10
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    Quantitative analysis of the tremor wavefield at Etna Volcano, Italy (2005)
    Elsevier
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: The properties of volcanic tremor wavefield at Mt. Etna Volcano, Italy, are investigated using data from two dense, smallaperture arrays of short-period seismometers deployed on the North and South flank of the volcano. Spectral analysis shows that most of the seismic energy is associated to several, narrow spectral peaks spanning the 1–5 Hz frequency band. Analysis of simultaneous recordings evidences that most of these peaks are common to different sites, thus suggesting a source effect as the origin of this energy. Frequency-slowness analyses evidence a complex wavefield, where body- and surface-waves alternatively dominate depending on the frequency band and component of motion taken into account. Surface waves are found to dominate at frequencies below 1 Hz and above 3 Hz. Conversely, the 0.8–2.3 Hz vertical- and radial-component wavefields at both arrays exhibit a nondispersive nature, with apparent velocities spanning the 1–2 s/km range. Particle motion analysis suggests these arrivals are associated to both P- and SV-waves inciding at shallow angles. At the northern array, back-azimuths of these waves encompass the whole summit crater area. At the southern array, back-azimuths are instead clustered around a direction pointing about 500 m east of the SE crater. At frequency around 4 Hz, the dominant direction of wave propagation at the southern site shifts about 30jW, pointing to the Bocca-Nuova/Voragine craters, and concordance of location is found with the source imaged by the northern array. The 0.8–2.3 Hz transverse-component of motion depicts velocities of about 0.5 km/s, a value which is about three times lower than those associated to the vertical and radial components. Results from polarization analyses at the two array sites depict the dominance of horizontal, linear particle motion oriented transversally with respect to the source direction. Polarization ellipsoids at the stations of the sparse network all depict a quasi-horizontal setting. With two exceptions, the direction of particle motion is always oriented tangentially to the summit volcanic edifice. The origin of the large transverse motion observed at the two array sites is thus attributed to SH waves generated by free-surface interaction of waves impinging the concave topography. The correlation method is used to derive the dispersion properties of short-period (0.5–5 Hz) Rayleigh waves, from which the shallow shear-wave velocity structures are derived for beneath the two semicircular arrays. Using a probabilistic approach, we invert slowness data measured at the two dense arrays for retrieving source location and extent. The joint inversion of slowness data from the two arrays point to different sources. This observation is interpreted in terms of ray bending associated to lateral heterogeneity and/or strong topographic effects on wave propagation. Once the propagation effects are taken into account, the most probable source locations are associated to a shallow region encompassing the summit craters and the eruptive fissures active at the time of the experiment (September 1999).
    Beschreibung: Published
    Beschreibung: 223-245
    Beschreibung: partially_open
    Schlagwort(e): Mount Etna ; Volcanic tremor ; Volcanic seismicity ; Seismic monitoring ; 04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Format: 487 bytes
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