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  • 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk  (28)
  • 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion  (16)
  • 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas  (11)
  • Springer  (28)
  • American Geophysical Union  (25)
  • Essen : Verl. Glückauf
  • International Union of Crystallography
  • Krefeld : Geologischer Dienst Nordhein-Westfalen
  • 2005-2009  (53)
  • 1940-1944
Sammlung
Verlag/Herausgeber
Erscheinungszeitraum
Jahr
  • 1
    Publikationsdatum: 2020-11-16
    Beschreibung: Geological, geophysical and geotechnical investigations, for the characterization of the strong-motion recording sitesmanaged by the ItalianCivil Protection, have been carried out in the framework of the project “Italian strong-motion database in the period 1972–2004”. The project aimed at creating an updated database of strong-motion data acquired in Italy by different institutions in the time span 1972–2004, and at improving the quality of disseminated data. This article illustrates the state of the recording site characterization before the beginning of the project, explains the criteria adopted to select the sites where geophysical/ geotechnical investigation have been performed and describes the results of the promoted field surveys.
    Beschreibung: Published
    Beschreibung: 1189–1207
    Beschreibung: 4IT. Banche dati
    Beschreibung: JCR Journal
    Beschreibung: open
    Schlagwort(e): site ; characterization ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Standort Signatur Erwartet Verfügbarkeit
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  • 2
    facet.materialart.
    Unbekannt
    American Geophysical Union
    In:  An edited version of this paper was published by AGU. Copyright (2009) American Geophysical Union.
    Publikationsdatum: 2017-04-04
    Beschreibung: In this paper we investigate ground motion properties in the western part of the Pernicana fault. This is the major fault of Mount Etna and drives the dynamic evolution of the area. In a previous work, Rigano et al. (2008) showed that a significant horizontal polarization characterizes ground motion in fault zones of Mount Etna, both during earthquakes and ambient vibrations. We have performed denser microtremor measurements in the NE rift segment and in intensely deformed zones of the Pernicana fault at Piano Pernicana. This study includes mapping of azimuth-dependent horizontal-to-vertical spectral ratios along and across the fault, frequency–wave number techniques applied to array data to investigate the nature of ambient vibrations, and polarization analysis through the conventional covariance matrix method. Our results indicate that microtremors are likely composed of volcanic tremor. Spectral ratios show strong directional resonances of horizontal components around 1 Hz when measurements enter the most damaged part of the fault zone. Their polarization directions show an abrupt change, by 20° to 40°, at close measurements between the northern and southern part of the fault zone. Recordings of local earthquakes at one site in the fault zone confirm the occurrence of polarization with the same angle found using volcanic tremor. We have also found that the directional effect is not time-dependent, at least at a seasonal scale. This observation and the similar behavior of volcanic tremors and earthquake-induced ground motions suggest that horizontal polarization is the effect of local fault properties. However, the 1-Hz resonant frequency cannot be reproduced using the 1-D vertically varying model inferred from the array data analysis, suggesting a role of lateral variations of the fault zone. Although the actual cause of polarization is unknown, a role of stress-induced anisotropy and microfracture orientation in the near-surface lavas of the Pernicana fault can be hypothesized consistently with the sharp rotation of the polarization angle within the damaged fault zone.
    Beschreibung: Published
    Beschreibung: B10308
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: JCR Journal
    Beschreibung: open
    Schlagwort(e): Pernicana fault, fault zone, volcanic tremor, polarization, directional resonance ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Standort Signatur Erwartet Verfügbarkeit
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  • 3
    Publikationsdatum: 2017-04-04
    Beschreibung: The Italian strong-motion database was created during a joint project between Istituto Nazionale di Geofisica e Vulcanologia (INGV, Italian Institute for Geophysics and Vulcanology) and Dipartimento della Protezione Civile (DPC, Italian Civil Protection). The aim of the project was the collection, homogenization and distribution of strong motion data acquired in Italy in the period 1972-2004 by different institutions, namely Ente Nazionale per l’Energia Elettrica (ENEL, Italian electricity company), Ente per le Nuove tecnologie, l’Energia e l’Ambiente (ENEA, Italian energy and environment organization) and DPC. Recently the strong-motion data relative to the 23th December 2009, Parma (Mw=5.4 and Mw=4.9) and to the 2009 L’Aquila sequence (13 earthquakes with 4.1Mw6.3) were included in the ITACA database (beta release). The database contains 7038 waveforms from analog and digital instruments, generated by 1019 earthquakes with magnitude up to 6.9 and can be accessed on-line at the web site http://itaca.mi.ingv.it. The strong motion data are provided in the unprocessed and processed versions. This article describes the steps followed to process the acceleration time series recorded by analogue and digital instruments. The procedures implemented involve: baseline removal, instrumental correction, band pass filtering with acausal filters, integration of the corrected acceleration in order to obtain velocity and displacement waveforms, computation of acceleration response spectra and strong motion parameters. This procedure is applied to each accelerogram, is realised to preserve the low frequency content of the records.
    Beschreibung: In press
    Beschreibung: 5.2. TTC - Banche dati di sismologia strumentale
    Beschreibung: JCR Journal
    Beschreibung: open
    Schlagwort(e): strong-motion ; processing ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Standort Signatur Erwartet Verfügbarkeit
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  • 4
    Publikationsdatum: 2017-04-04
    Beschreibung: Volcanoes deform as a consequence of the rise and storage of magma; once magma reaches a critical pressure, an eruption occurs. However, how the edifice deformation relates to its eruptive behavior is poorly known. Here, we produce a joint interpretation of spaceborne InSAR deformation measurements and volcanic activity at Mt. Etna (Italy), between 1992 and 2006. We distinguish two volcano-tectonic behaviors. Between 1993 and 2000, Etna inflated with a starting deformation rate of 1 cm yr 1 that progressively reduced with time, nearly vanishing between 1998 and 2000; moreover, low-eruptive rate summit eruptions occurred, punctuated by lava fountains. Between 2001 and 2005, Etna deflated, feeding higher-eruptive rate flank eruptions, along with large displacements of the entire East-flank. These two behaviors, we suggest, result from the higher rate of magma stored between 1993 and June 2001, which triggered the emplacement of the dike responsible for the 2001 and 2002–2003 eruptions. Our results clearly show that the joint interpretation of volcano deformation and stored magma rates may be crucial in identifying impending volcanic eruptions.
    Beschreibung: This work was partly funded by INGV and the Italian DPC and was supported by ASI, the Preview Project and CRdC-AMRA. DPC-INGV Flank project providing the funds for the publication fees.
    Beschreibung: Published
    Beschreibung: L02309
    Beschreibung: 1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
    Beschreibung: 1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani
    Beschreibung: 1.10. TTC - Telerilevamento
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: 4.5. Degassamento naturale
    Beschreibung: JCR Journal
    Beschreibung: partially_open
    Schlagwort(e): deformation ; eruptions ; Mt. Etna ; eruptive cycle ; InSAR ; 04. Solid Earth::04.01. Earth Interior::04.01.99. General or miscellaneous ; 04. Solid Earth::04.01. Earth Interior::04.01.02. Geological and geophysical evidences of deep processes ; 04. Solid Earth::04.03. Geodesy::04.03.99. General or miscellaneous ; 04. Solid Earth::04.03. Geodesy::04.03.06. Measurements and monitoring ; 04. Solid Earth::04.03. Geodesy::04.03.07. Satellite geodesy ; 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::04.04. Geology::04.04.12. Fluid Geochemistry ; 04. Solid Earth::04.07. Tectonophysics::04.07.99. General or miscellaneous ; 04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamics ; 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::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.07. Instruments and techniques ; 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
    Standort Signatur Erwartet Verfügbarkeit
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  • 5
    Publikationsdatum: 2017-04-04
    Beschreibung: Volcanic and geothermal areas are one of the major natural sources of H2S to the atmosphere. Its environmental impact is often the main cause of the opposition to the development of geothermal energy exploitation programs. In this paper we analyze the air concentrations and dispersion pattern of naturally emitted H2S at the geothermal area of Sousaki (Corinthia, Greece). Measurements, made with a network of passive samplers, evidence a rapid decrease of concentration values away from the emission points. The fact that the decrease is more pronounced in the summer with respect to the winter indicates that it is not only due to a dilution effect, but also to redox reactions favoured by higher temperatures and intense sunlight typical of the summer period.
    Beschreibung: Published
    Beschreibung: 1723-1728
    Beschreibung: 1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Hydrogen sulphide ; Environmental impact of volcanic activity ; Gas hazard ; Passive samplers ; 01. Atmosphere::01.01. Atmosphere::01.01.03. Pollution ; 01. Atmosphere::01.01. Atmosphere::01.01.07. Volcanic effects ; 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::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Standort Signatur Erwartet Verfügbarkeit
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  • 6
    Publikationsdatum: 2017-04-04
    Beschreibung: A revised Italian strong motion archive has become available since July 2007, including all the records of the strongest events occurred from 1972 to 2004. It contains the uncorrected and corrected accelerograms and the metadata relevant to seismic events, recording stations and instruments added after a careful revision. The availability of this archive allowed us to perform a first step towards an update of the reference ground motion prediction equations for Italy, which were evaluated by Sabetta and Pugliese in (Bull Seismol Soc Am 77:1491–1513, 1987), for peak ground acceleration and velocity, and subsequently extended to the 5% damped pseudovelocity response spectra in 1996. A subset with the 27 major earthquakes occurred in Italy from 1972 to 2002, in the magnitude range 4.6–6.9, was extracted and 235 good quality waveforms were selected, recorded at distances up to 183 km. The goodness of fit of the Sabetta and Pugliese (Bull Seismol Soc Am 86:337–352, 1996) model was explored using two independent statistical approaches (Spudich et al. Bull Seismol Soc Am 89:1156–1170, 1999 and Scherbaum et al. Bull Seismol Soc Am 94:2164– 2185, 2004). The results obtained show that the Sabetta and Pugliese (Bull Seismol Soc Am 77:1491–1513, 1987) does not adequately fit the new strong-motion data set, for its small standard deviation and its non-zero bias. In particular, the most noteworthy result is that the Sabetta and Pugliese (Bull Seismol Soc Am 77:1491–1513, 1987) over-predicts peak ground acceleration and velocity at rock sites. New coefficients for the prediction of horizontal peak ground acceleration, peak ground velocity and acceleration response spectra, adopting the same functional form in Sabetta and Pugliese (Bull Seismol Soc Am 77:1491–1513, 1987), were then evaluated in order to fit the new data set. This paper illustrates the steps made to update the existing ground motion prediction equations for Italy, discusses their limitations and provides the basis for future developments.
    Beschreibung: Published
    Beschreibung: 591–608
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): ground motion prediction ; equation ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 7
    Publikationsdatum: 2017-04-04
    Beschreibung: The Italian Accelerometic Archive (ITACA) was created in 2007 during a joint project between the Italian Institute for Geophysics and Vulcanology (Istituto Nazionale di Geofisica e Vulcanologia, INGV) and the Italian Civil Protection (Dipartimento della Protezione Civile, DPC). The project, started in 2006, had the aim of filling the data gap of existing strong motion databases and facilitating strong motion data users in obtaining good quality waveforms, through the collection, homogenization and distribution of strong motion data acquired during the period 1972-2004 in Italy by different institutions (Ente Nazionale per l’Energia Elettrica, ENEL, Italian electricity company; Ente per le Nuove tecnologie, l’Energia e l’Ambiente, ENEA, Italian energy and environment organization DPC). The compiled database contains 2182 three-component waveforms generated by 1008 earthquakes with a maximum moment magnitude of 6.9 (1980 Irpinia earthquake) and can be accessed on-line at the portal denominated ITACA at the site http://itaca.mi.ingv.it, where a wide range of search tools enables the user to interactively retrieve events, recording stations and waveforms with particular characteristics, whose parameters can be specified, as needed, through user friendly interfaces. A range of display options allows users to view data in different contexts, extract and download time series and spectral data. This article describes the state of the art up to 2006 and the activities which led to the completion of the project.
    Beschreibung: In press
    Beschreibung: 5.2. TTC - Banche dati di sismologia strumentale
    Beschreibung: JCR Journal
    Beschreibung: open
    Schlagwort(e): strong-motion ; database ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Standort Signatur Erwartet Verfügbarkeit
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  • 8
    Publikationsdatum: 2017-04-04
    Beschreibung: A set of Ground Motion Prediction Equations (GMPEs) for the Italian territory is proposed, exploiting a new strong-motion data set become available since July 2007 through the Italian Accelerometric Archive (ITACA). The data set is composed by 561 three-component waveforms from 107 earthquakes with moment magnitude in the range 4.0–6.9, occurred in Italy from 1972 to 2007 and recorded by 206 stations at distances up to 100 km. The functional form used to derive GMPEs in Italy (Sabetta and Pugliese in Bull Seismol Soc Am 86(2):337–352, 1996) has been modified introducing a quadratic term for magnitude and a magnitude-dependent geometrical spreading. The coefficients for the prediction of horizontal and vertical peak ground acceleration, peak ground velocity and 5% damped acceleration response spectra are evaluated. This paper illustrates the new data set, the regression analysis and the comparisons with recently derived GMPEs in Europe and in the Next Generation Attenuation of Ground Motions (NGA) Project.
    Beschreibung: In press
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: JCR Journal
    Beschreibung: open
    Schlagwort(e): ground motion ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 9
    Publikationsdatum: 2017-04-04
    Beschreibung: New Sr and Nd isotope data for whole rocks, glasses and minerals are combined to reconstruct the nature and origin of mixing end-members of the 200 km3 trachytic to phonolitic Campanian Ignimbrite (Campi Flegrei, Italy) magmatic system. The least-evolved magmatic end-member shows equilibrium between host glass and the majority of the phenocrysts and is less radiogenic in Sr and Nd than the most-evolved magma. On the contrary, only the Fe-rich pyroxene from the most-evolved erupted magma is in equilibrium with the matrix glass, while all other minerals are in isotopic disequilibrium. These magmas mixed prior to and during the Campanian Ignimbrite eruption and minerals were freely exchanged between the magma batches. Combining the results of the geochemical investigations on magma end-members with geophysical and geological data, we develop the following scenario. In stage 1, a parental, less differentiated magma rose into the middle crust, and evolved through combined crustal assimilation and crystal fractionation. In stage 2, the differentiated magma rose to shallower depth, fed the pre-Campanian Ignimbrite activity and evolved by further open-system processes into the most-evolved and most-radiogenic Campanian Ignimbrite end-member magma. In stage 3, new trachytic magma, isotopically distinct from the pre-Campanian Ignimbrite magmas, rose from ca. 6 km to shallower depth, recharged the most-evolved pre-Campanian Ignimbrite magma chamber, and formed the large and stratified Campanian Ignimbrite magmatic system. During the course of the Campanian Ignimbrite eruption, the two layers were tapped separately and/or simultaneously, and gave rise to the range of chemical and isotopic values displayed by the Campanian Ignimbrite pumices, glasses and minerals.
    Beschreibung: Published
    Beschreibung: 285-300
    Beschreibung: 2.3. TTC - Laboratori di chimica e fisica delle rocce
    Beschreibung: 3.5. Geologia e storia dei vulcani ed evoluzione dei magmi
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Campanian Ignimbrite ; Radiogenic isotopes ; Mixing process ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Standort Signatur Erwartet Verfügbarkeit
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  • 10
    Publikationsdatum: 2017-04-04
    Beschreibung: Following the 2001 and 2002–2003 flank eruptions, activity resumed at Mt. Etna on 7 September 2004 and lasted for about 6 months. This paper presents new petrographic, major and trace element, and Sr–Nd isotope data from sequential samples collected during the entire 2004–2005 eruption. The progressive change of lava composition allowed defining three phases that correspond to different processes controlling magma dynamics inside the central volcano conduits. The compositional variability of products erupted up to 24 September is well reproduced by a fractional crystallization model that involves magma already stored at shallow depth since the 2002–2003 eruption. The progressive mixing of this magma with a distinct new one rising within the central conduits is clearly revealed by the composition of the products erupted from 24 September to 15 October. After 15 October, the contribution from the new magma gradually becomes predominant, and the efficiency of the mixing process ensures the emission of homogeneous products up to the end of the eruption. Our results give insights into the complex conditions of magma storage and evolution in the shallow plumbing system of Mt. Etna during a flank eruption. Furthermore, they confirm that the 2004–2005 activity at Etna was triggered by regional movements of the eastern flank of the volcano. They caused the opening of a complex fracture zone extending ESE which drained a magma stored at shallow depth since the 2002–2003 eruption. This process favored the ascent of a different magma in the central conduits, which began to be erupted on 24 September without any significant change in eruptive style, deformation, and seismicity until the end of eruption.
    Beschreibung: Published
    Beschreibung: 781–793
    Beschreibung: 2.3. TTC - Laboratori di chimica e fisica delle rocce
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Geochemistry ; Isotopic compositions ; Magma feeding system ; Magma mixing ; Mt. Etna ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 11
    Publikationsdatum: 2020-12-14
    Beschreibung: Stromboli volcano is famous in the scientific literature for its persistent state of activity, which began about 1500 years ago and consists of continuous degassing and mild intermittent explosions (normal Strombolian activity). Rare lava emissions and sporadic more violent explosive episodes (paroxysms) also occur. Since its formation, the present-day activity has been dominated by the emission of two basaltic magmas, differing chiefly in their crystal and volatile contents, whose characteristics have remained constant until now. The normal Strombolian activity and lava effusions are fed by a crystal-rich, degassed magma, stored within the uppermost part of the plumbing system, whereas highly vesicular, crystal-poor light-colored pumices are produced during paroxysms testifying to the ascent of volatile-rich magma batches from deeper portions of the magmatic system. Mineralogical, geochemical, and isotopic data, together with data on the volatile contents of magmas, are presented here with the aim of discussing (1) the relationships between the different magma batches erupted at Stromboli, (2) the mechanisms of their crystallization and transfer, (3) the plumbing system and triggering mechanisms of Strombolian eruptions.
    Beschreibung: Unpublished
    Beschreibung: 20
    Beschreibung: 3.5. Geologia e storia dei sistemi vulcanici
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: reserved
    Schlagwort(e): Stromboli volcano ; Basaltic explosive activity ; Basaltic pumice ; Plumbing system ; 04. Solid Earth::04.04. Geology::04.04.05. Mineralogy and petrology ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
    Standort Signatur Erwartet Verfügbarkeit
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  • 12
    Publikationsdatum: 2017-04-04
    Beschreibung: Stromboli is a 3000-m-high, conical island-arc volcano rising to 900 m above sea level. It is the most active volcano of the Aeolian Archipelago in the Tyrrhenian Sea (Italy). In the last 13 Kr four large-volume (1 km3) flank collapses have played an important role in shaping the northwestern flank (Sciara del Fuoco- SdF) of the volcano. These flank collapses have the potential to cause hazardous tsunamis in the Aeolian islands and farther afield along the Italian coast. In addition, smaller volume, much more frequent partial collapses of the SdF have been shown to be tsunami generating, potentially hazardous events One such partial collapse occurred on 30/12/2002, on the north-western flank of the island. The resulting landslide generated a 10-m-high tsunami that impacted the island. Multibeam bathymetry, side-scan sonar and seabed visual observations reveal that 25-30 x 106 m3 of sediments were deposited on the offshore from the Sciara del Fuoco landslide. Sediment samples have led to the recognition of a proximal coarse-grained landslide deposit on the volcano slope and a distal, cogenetic, sandy turbidite 24 km from the Stromboli shoreline. The proximal landslide deposit consists of two contiguous facies: (1) a chaotic, coarse grained (meter- to centimetre-sized clasts) deposit and (2) a sand deposit containing a lower, cross bedded sand layer and an upper structureless, pebbly sand bed, capped by seafloor ripple bedforms. The ubiquitous sand facies develops laterally with and over the coarse-grained deposits. Distally, a capping 2-3 cm-thick sand layer, not present in a pre-landslide September 2002 core, is interpreted as the finer grained turbidite equivalent of the proximal deposits. Characteristics of the SdF landslide deposits suggest that they derive from cohesionless, sandy-matrix, density flows. Flow rheology resulted in segregation of the density flow into sand-rich and clast-rich regions. Our results show that a range of density flow transitions, based principally on particle concentration and grain-size partitioning of cohesionless parent flows, can be identified in the proximal and distaldeposits of this relatively small-scale landslide event on Stromboli.
    Beschreibung: Unpublished
    Beschreibung: 23
    Beschreibung: 2.3. TTC - Laboratori di chimica e fisica delle rocce
    Beschreibung: 3.5. Geologia e storia dei sistemi vulcanici
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: open
    Schlagwort(e): Stromboli ; flank collapse ; tsunami ; submarine landslide deposits ; 04. Solid Earth::04.04. Geology::04.04.04. Marine geology ; 04. Solid Earth::04.04. Geology::04.04.08. Sediments: dating, processes, transport ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 13
    facet.materialart.
    Unbekannt
    Springer
    Publikationsdatum: 2017-04-04
    Beschreibung: A series of experiments created melt inclusions in plagioclase and pyroxene crystals grown from a basaltic melt at 1,150 C, 1.0 GPa to investigate diffusive fractionation during melt inclusion formation; additionally, P diffusion in a basaltic melt was measured at 1.0 GPa. Melt inclusions and melts within a few 100 microns of plagioclase– melt interfaces were analyzed for comparison with melt compositions far from the crystals. Melt inclusions and melt compositions in the boundary layer close to the crystal–melt interface were similar, but both differ significantly in incompatible element concentrations from melt found greater than approximately 200 microns away from the crystals. The compositional profiles of S, Cl, P, Fe, and Al in the boundary layers were successfully reproduced by a two-step model of rapid crystal growth followed by diffusive relaxation toward equilibrium after termination of crystal growth. Applying this model to investigate possible incompatible element enrichment in natural melt inclusions demonstrated that at growth rates high enough to create the conditions for melt inclusion formation, *10-9–10-8 m s-1, the concentration of water in the boundary layer near the crystal was similar to that of the bulk melt because of its high diffusion coefficient, but sulfur, with a diffusivity similar to major elements and CO2, was somewhat enriched in the boundary layer melt, and phosphorus, with its low diffusion coefficient similar to other high-field strength elements and rare earth elements, was significantly enriched. Thus, the concentrations of sulfur and phosphorus in melt inclusions may over-estimate their values in the bulk melt, and other elements with similar diffusion coefficients may also be enriched in melt inclusions relative to the bulk melt.
    Beschreibung: Natural Sciences and Engineering Research Council of Canada Discovery grant; Istituto Nazionale di Geofisica and Vulcanologia, Italy
    Beschreibung: Published
    Beschreibung: 377-395
    Beschreibung: 2.3. TTC - Laboratori di chimica e fisica delle rocce
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Melt inclusions ; Phosphorus diffusion ; Crystal growth ; Diffusive Fractionation ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 14
    Publikationsdatum: 2017-04-04
    Beschreibung: The main purpose of this paper is to introduce a Bayesian event tree model for eruption forecasting (BET_EF). The model represents a flexible tool to provide probabilities of any specific event at which we are interested in, by merging all the relevant available information, such as theoretical models, a priori beliefs, monitoring measures, and any kind of past data. BET_EF is based on a Bayesian procedure and it relies on the fuzzy approach to manage monitoring data. The method deals with short- and long-term forecasting, therefore it can be useful in many practical aspects, as land use planning, and during volcanic emergencies. Finally, we provide the description of a free software package that provides a graphically supported computation of short- to long-term eruption forecasting, and a tutorial application to the recent MESIMEX exercise at Vesuvius.
    Beschreibung: Published
    Beschreibung: 623-632
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: JCR Journal
    Beschreibung: partially_open
    Schlagwort(e): eruption forecasting ; event tree ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 15
    Publikationsdatum: 2017-04-04
    Beschreibung: The 2002–2003 Etna eruption is studied through earthquake distributions and surface fracturing. In September 2002, earthquake-induced surface rupture (sinistral offset 0.48 m) occurred along the E-W striking Pernicana Fault (PF), on the NE flank. In late October, a flank eruption accompanied further ( 0.77 m) surface rupturing, reaching a total sinistral offset of 1.25 m; the deformation then propagated for 18 km eastwards to the coastline (sinistral offset 0.03 m) and southwards, along the NW-SE striking Timpe (dextral offset 0.04 m) and, later, Trecastagni faults (dextral offset 0.035 m). Seismicity (〈4 km bsl) on the E flank accompanied surface fracturing: fault plane solutions indicate an overall ESEWNWextension direction, consistent with ESE slip of the E flank also revealed by ground fractures. A three-stage model of flank slip is proposed: inception (September earthquake), climax (accelerated slip and eruption) and propagation (E and S migration of the deformation).
    Beschreibung: Published
    Beschreibung: 2286
    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: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): volcano seismology ; surface fracturing ; flank slip ; eruption ; Etna ; 04. Solid Earth::04.01. Earth Interior::04.01.99. General or miscellaneous ; 04. Solid Earth::04.01. Earth Interior::04.01.02. Geological and geophysical evidences of deep processes ; 04. Solid Earth::04.02. Exploration geophysics::04.02.99. General or miscellaneous ; 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::04.06. Seismology::04.06.99. General or miscellaneous ; 04. Solid Earth::04.06. Seismology::04.06.01. Earthquake faults: properties and evolution ; 04. Solid Earth::04.06. Seismology::04.06.02. Earthquake interactions and probability ; 04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology ; 04. Solid Earth::04.06. Seismology::04.06.11. Seismic risk ; 04. Solid Earth::04.07. Tectonophysics::04.07.99. General or miscellaneous ; 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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  • 16
    Publikationsdatum: 2017-04-04
    Beschreibung: The 5 April 2003 explosive eruption at Stromboli emplaced typical basaltic scoria, pumice, and lithic blocks. This paper reports a detailed set of mineralogical, geochemical, and isotopic data on the juvenile ejecta and fresh subvolcanic blocks, including micro-Sr isotope analyses and major and dissolved volatile element contents in olivine-hosted melt inclusions. The juvenile ejecta have compositions similar to those of their analogs from previous paroxysms; the 2003 pumice, however, does not contain stable high-MgO olivine, usually typical of large-scale paroxysms and has lower compatible element contents. Texture, composition, and Sr isotope disequilibrium of crystals in pumice indicate that most of them are inherited from the shallow crystal-rich magma and/or crystal mush. The most primitive magma is recorded as rare melt inclusion in olivine Fo85–86. It has a typical S/Cl (1.1) and a total volatile content of 3.1 wt % from which the total fluid pressure was evaluated ≥240 MPa. Hence, moderate pressure conditions can be envisaged for the mechanism triggering the April 2003 paroxysm. The subvolcanic blocks are shoshonitic basalts with 45–50 vol % of phenocrysts (plagioclase + clinopyroxene + olivine). The late-stage crystallization of the crystal-rich magma lead to the formation of Na-sanidine with plagioclase An60–25 + olivine Fo68–49 + Timagnetite ± apatite ± phlogopite ± ilmenite assemblage. Mineralogy, chemistry, and Sr–Nd isotopic signatures of the subvolcanic blocks indicate they represent the slowly cooled equivalents of batches of crystal-rich basaltic magma stored in the uppermost subvolcanic feeding system. Cooling might be facilitated by short breaks in the summit crater activity.
    Beschreibung: Unpublished
    Beschreibung: 17
    Beschreibung: 2.3. TTC - Laboratori di chimica e fisica delle rocce
    Beschreibung: 3.5. Geologia e storia dei sistemi vulcanici
    Beschreibung: open
    Schlagwort(e): Stromboli volcano ; Paroxysmal activity ; Basaltic pumice ; Volatile content ; Mineralogy ; Geochemistry ; Sr isotope ; 04. Solid Earth::04.04. Geology::04.04.05. Mineralogy and petrology ; 04. Solid Earth::04.04. Geology::04.04.07. Rock geochemistry ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
    Standort Signatur Erwartet Verfügbarkeit
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  • 17
    Publikationsdatum: 2017-04-04
    Beschreibung: We consider the process of slow extrusion of very viscous magma that forms lava domes. Dome-building eruptions are commonly associated with hazardous phenomena, in- cluding pyroclastic flows generated by dome collapses, explosive eruptions and volcanic blasts. These eruptions commonly display fairly regular alternations between pe- riods of high and low or no activity with time scales from hours to years. Usually hazardous phenomena are asso- ciated with periods of high magma discharge rate, thus, understanding the causes of pulsatory activity during ex- trusive eruptions is an important step towards forecasting volcanic behavior, especially the transition to explosive ac- tivity when magma discharge rate increases by a few orders of magnitude. In recent years the risks have increased be- cause the population density in the vicinity of many active volcanoes has increased.
    Beschreibung: Published
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: open
    Schlagwort(e): Volcanic Eruptions ; Cyclicity ; During Lava ; 04. Solid Earth::04.01. Earth Interior::04.01.99. General or miscellaneous ; 04. Solid Earth::04.08. Volcanology::04.08.04. Thermodynamics ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 18
    Publikationsdatum: 2023-01-16
    Beschreibung: The 5 April 2003 eruption of Stromboli volcano (Italy) was the most violent in the past 50 years. It was also the best documented due to the accurate geophysical monitoring of the ongoing effusive eruption. Detailed field studies carried out a few hours to a few months after the event provided further information that were coupled with visual documentation to reconstruct the explosive dynamics. The eruption consisted of an 8-min-long explosive event preceded by a short-lived precursory activity that evolved into the impulsive ejection of gas and pyroclasts. Meter-sized ballistic blocks were launched to altitudes of up to 1400 m above the craters falling on the volcano flanks and on the village of Ginostra, about 2 km far from the vent. The vertical jet of gas and pyroclasts above the craters fed a convective plume that reached a height of 4 km. The calculated erupted mass yielded values of 1.1–1.4 × 108 kg. Later explosions generated a scoria flow deposit, with an estimated mass of 1.0–1.3 × 107 kg. Final, waning ash explosions closet the event. The juvenile fraction consisted of an almost aphyric, highly vesicular pumice mingled with a shallow-derived, crystal-rich, moderately vesicular scoria. Resuming of the lava emission a few hours after the paroxysm indicate that the shallow magmatic system was not significantly modified during the explosions. Combination of volume data with duration of eruptive phases allowed us to estimate the eruptive intensity: during the climactic explosive event, the mass discharge rate was between 106 and 107 kg/s, whereas during the pyroclastic flow activity, it was 2.8–3.6 × 105 kg/s. Strong similarities with other historical paroxysms at Stromboli suggest similar explosion dynamics.
    Beschreibung: Unpublished
    Beschreibung: 3.5. Geologia e storia dei sistemi vulcanici
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: open
    Schlagwort(e): Stromboli ; paroxysm ; explosive dynamics ; pyroclastic deposits ; ballistic ejecta ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 19
    Publikationsdatum: 2021-06-21
    Beschreibung: Earthquake early warning systems (EEWS), based on real-time prediction of ground motion or structural response measures, may play a role in re- ducing vulnerability and/or exposure of buildings and lifelines. Indeed, seismologists have recently developed efficient methods for real-time es- timation of an event’s magnitude and location based on limited informa- tion of the P-waves. Therefore, when an event occurs, estimates of magni- tude and source-to-site distance are available, and the prediction of the structural demand at the site may be performed by Probabilistic Seismic Hazard Analysis (PSHA) and then by Probabilistic Seismic Demand Analysis (PSDA) depending upon EEWS measures. Such an approach contains a higher level of information with respect to traditional seismic risk analysis and may be used for real-time risk management. However, this kind of prediction is performed in very uncertain conditions which may affect the effectiveness of the system and therefore have to be taken into due account. In the present study the performance of the EWWS under development in the Campania region (southern Italy) is assessed by simu- lation. The earthquake localization is formulated in a Voronoi cells ap- proach, while a Bayesian method is used for magnitude estimation. Simu- lation has an empirical basis but requires no recorded signals. Our results, in terms of hazard analysis and false/missed alarm probabilities, lead us to conclude that the PSHA depending upon the EEWS significantly improves seismic risk prediction at the site and is close to what could be produced if magnitude and distance were deterministically known.
    Beschreibung: Published
    Beschreibung: 211-232
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: reserved
    Schlagwort(e): Earthquake Early ; Campania Region ; 04. Solid Earth::04.06. Seismology::04.06.03. Earthquake source and dynamics ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion ; 04. Solid Earth::04.06. Seismology::04.06.11. Seismic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 20
    Publikationsdatum: 2021-06-15
    Beschreibung: To assess ways in which the products of explosive eruptions interact with human settlements, we performed volcanological and rock magnetic analyses on the deposits of the A.D. 79 eruption at the Pompeii excavations (Italy). During this eruption the Roman town of Pompeii was covered by 2.5 m of fallout pumice and then partially destroyed by pyroclastic density currents (PDCs). Anisotropy of magnetic susceptibility measurements performed on the fine matrix of the deposits allowed the quantification of the variations in flow direction and emplacement mechanisms of the parental PDCs that entered the town. These results, integrated with volcanological field investigations, revealed that the presence of buildings, still protruding through the fallout deposits, strongly affected the distribution and accumulation of the erupted products. All of the PDCs that entered the town, even the most dilute ones, were density stratified currents in which interaction with the urban fabric occurred in the lower part of the current. The degree of interaction varied mainly as a function of obstacle height and density stratification within the current. For examples, the lower part of the EU4pf current left deposits up to 3 m thick and was able to interact with 2- to 4-m-high obstacles. However, a decrease in thickness and grain size of the deposits across the town indicates that even though the upper portion of the current was able to decouple from the lower portion, enabling it to flow over the town, it was not able to fully restore the sediment supply to the lower portion in order to maintain the deposition observed upon entry into the town.
    Beschreibung: Published
    Beschreibung: B05213
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Pompeii ; facies ; magnetic fabric ; pyroclastic density currents ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 21
    Publikationsdatum: 2021-06-15
    Beschreibung: During the A.D. 79 eruption of Vesuvius, Italy, the Roman town of Pompeii was covered by 2.5 m of pyroclastic fall pumice and then partially destroyed by pyroclastic density currents (PDCs). Thermal remanent magnetization measurements performed on the lithic and roof tile fragments embedded in the PDC deposits allow us to quantify the variations in the temperature (Tdep) of the deposits within and around Pompeii. These results reveal that the presence of buildings strongly influenced the deposition temperature of the erupted products. The first two currents, which entered Pompeii at a temperature around 300–360°C, show drastic decreases in the Tdep, with minima of 100–140°C, found in the deposits within the town. We interpret these decreases in temperature as being the result of localized interactions between the PDCs and the city structures, which were only able to affect the lower part of the currents. Down flow of Pompeii, the lowermost portion of the PDCs regained its original physical characteristics, emplacing hot deposits once more. The final, dilute PDCs entered a town that was already partially destroyed by the previous currents. These PDCs left thin ash deposits, which mantled the previous ones. The lack of interaction with the urban fabric is indicated by their uniform temperature everywhere. However, the relatively high temperature of the deposits, between 140 and 300°C, indicates that even these distal, thin ash layers, capped by their accretionary lapilli bed, were associated with PDCs that were still hot enough to cause problems for unsheltered people.
    Beschreibung: Published
    Beschreibung: B05214
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Pompeii ; temperature ; magnetic fabric ; pyroclastic density currents ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 22
    Publikationsdatum: 2017-04-04
    Beschreibung: Volcanic hazard assessment is a basic ingredient for risk-based decision-making in land-use planning and emergency management. Volcanic hazard is defined as the probability of any particular area being affected by a destructive volcanic event within a given period of time (Fournier d’Albe 1979). The probabilistic nature of such an important issue derives from the fact that volcanic activity is a complex process, characterized by several and usually unknown degrees of freedom that are often linked by nonlinear relationships (e.g. Bak et al. 1988). Except in sporadic cases, the result of this complexity is an intrinsic, and perhaps unavoidable, unpredictability of the time evolution of the volcanic system from a deterministic point of view.
    Beschreibung: Published
    Beschreibung: open
    Schlagwort(e): model ; volcanic risk ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book
    Format: 137534 bytes
    Format: application/pdf
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  • 23
    Publikationsdatum: 2017-04-04
    Beschreibung: In order to empirically obtain the scaling relationships for the high-frequency ground motion in the Western Alps (NW Italy), regressions are carried out on more than 7500 seismograms from 957 regional earthquakes. The waveforms were selected from the database of 6 three-component stations of the RSNI (Regional Seismic network of Northwestern Italy). The events,MW ranging between 1.2 and 4.8, were recorded within a hypocentral distance of 200 km during the time period: 1996–2001. The peak ground velocities are measured in selected narrow-frequency bands, between 0.5 and 14 Hz. Results are presented in terms of a regional attenuation function for the vertical ground motion, a set of vertical excitation terms at the reference station STV2 (hard-rock), and a set of site terms (vertical and horizontal), all relative to the vertical component of station STV2. The regional propagation of the ground motion is modeled after quantifying the expected duration of the seismic motion as a function of frequency and hypocentral distance. A simple functional form is used to take into account both the geometrical and the anelastic attenuation: a multi-variable grid search yielded a quality factor Q( f ) = 310 f 0.20, together with a quadri-linear geometrical spreading at low frequency. A simpler, bilinear geometrical spreading seems to be more appropriate at higher frequencies (f 〉 1.0 Hz). Excitation terms are matched by using a Brune spectral model with variable, magnitude-dependent stress drop: at Mw 4.8, we used σ = 50MPa. A regional distanceindependent attenuation parameter is obtained (κ0 = 0.012 s) by modelling the average spectral decay at high frequency of small earthquakes. In order to predict the absolute levels of ground shaking in the region, the excitation/attenuation model is used through the Random Vibration Theory (RVT) with a stochastic point-source model. The expected peak-ground accelerations (PGA) are compared with the ones derived by Ambraseys et al. (1996) for the Mediterranean region and by Sabetta and Pugliese (1996) for the Italian territory.
    Beschreibung: Published
    Beschreibung: 315-333
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Attenuation ; Ground motion ; Western Alps ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 24
    Publikationsdatum: 2017-04-04
    Beschreibung: The main purpose of this paper is to introduce a Bayesian event tree model for eruption forecasting (BET EF). The model represents a flexible tool to provide probabilities of any specific event at which we are interested in, by merging all the relevant available information, such as theoretical models, a priori beliefs, monitoring measures, and any kind of past data. BET EF is based on a Bayesian procedure and it relies on the fuzzy approach to manage monitoring data. The method deals with short- and long-term forecasting, therefore it can be useful in many practical aspects, as land use planning, and during volcanic emergencies. Finally, we provide the description of a free software package that provides a graphically supported computation of short- to long-term eruption forecasting, and a tutorial application to the recent MESIMEX exercise at Vesuvius.
    Beschreibung: Published
    Beschreibung: on line first
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: JCR Journal
    Beschreibung: partially_open
    Schlagwort(e): Eruption forecasting ; Long- and short-term volcanic hazard ; Bayesian inference ; Event tree ; Fuzzy sets ; MESIMEX ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
    Standort Signatur Erwartet Verfügbarkeit
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  • 25
    facet.materialart.
    Unbekannt
    American Geophysical Union
    Publikationsdatum: 2017-04-04
    Beschreibung: One of the most critical practical actions to reduce volcanic risk is the evacuation of people from threatened areas during volcanic unrest. Despite its importance, this decision is usually arrived at subjectively by a few individuals, with little quantitative decision support. Here, we propose a possible strategy to integrate a probabilistic scheme for eruption forecasting and cost-benefit analysis, with an application to the call for an evacuation of one of the highest risk volcanoes: Vesuvius. This approach has the following merits. First, it incorporates a decision-analysis framework, expressed in terms of event probability, accounting for all modes of available hazard knowledge. Secondly, it is a scientific tool, based on quantitative and transparent rules that can be tested. Finally, since the quantitative rules are defined during a period of quiescence, it allows prior scrutiny of any scientific input into the model, so minimizing the external stress on scientists during an actual emergency phase. Whilst we specifically report the case of Vesuvius during the MESIMEX exercise, the approach can be generalized to other types of natural catastrophe.
    Beschreibung: Published
    Beschreibung: L22310
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: JCR Journal
    Beschreibung: partially_open
    Schlagwort(e): evacuation ; probabilistic eruption forecasting ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 26
    Publikationsdatum: 2017-04-04
    Beschreibung: For early-warning applications in particular, the reliability and efficiency of rapid scenario generation strongly depend on the availability of reliable strong ground-motion prediction tools. If shake maps are used to represent patterns of potential damage as a consequence of large earthquakes, attenuation relations are used as a tool for predicting peak ground-motion parameters and intensities. One of the limitations in the use of attenuation relations is that these have only rarely been retrieved from data collected in the same tectonic environment in which the prediction has to be performed. As a consequence, strong ground motion can result in underestimations or overestimations with respect to the recorded data. This also holds for Italy, and in particular for the Southern Apennines, due to limitations in the available databases, both in terms of distances and magnitude. Moreover, for “real-time” early-warning applications, it is important to have attenuation models for which the parameters can be easily upgraded when new data are collected, whether this has to be done during the earthquake rupture occurrence or in the post-event, when all the strong motion waveforms are available. Here we present a strong-motion attenuation relation for early-warning applications in the Campania region (Southern Apennines), Italy. The model has a classical analytical formulation, and its coefficients were retrieved from a synthetic strong-motion database created by using a stochastic approach. The input parameters for the simulation technique were obtained through the spectral analysis of waveforms of earthquakes recorded by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) network for a magnitude range Md (1.5,5.0) in the last fifteen years, and they have been extrapolated to cover a larger range. To validate the inferred relation, comparisons with two existing attenuation relations are presented. The results show that the calibration of the attenuation parameters, i.e., geometric spreading, quality factor Q, static stress drop values along with their uncertainties, are the main concern.
    Beschreibung: Published
    Beschreibung: 133-152
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: reserved
    Schlagwort(e): A Strong Motion ; Earlywarning ; 04. Solid Earth::04.06. Seismology::04.06.03. Earthquake source and dynamics ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion ; 04. Solid Earth::04.06. Seismology::04.06.11. Seismic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 27
    Publikationsdatum: 2017-04-04
    Beschreibung: In the framework of an ongoing project financed by the Campania Region, a prototype system for seismic early and post-event warning is being developed and tested, based on a dense, wide dynamic seismic network (ISNet) and under installation in the Apennine belt region. This paper reports the characteristics of the seismic network, focussing on the required technological innovation of the different seismic network components (data-logger, sensors and data communication). To ensure a highly dynamic recording range, each station is equipped with two types of sensors: a strong-motion accelerometer and a velocimeter. Data acquisition at the seismic stations is performed using Osiris-6 model data-loggers made by Agecodagis. Each station is supplied with two (120 W) solar panels and two 130 Ah gel cell batteries, ensuring 72-h autonomy for the seismic and radio communication equipment. The site is also equipped with a GSM/GPRS programmable control/alarm system connected to several environmental sensors (door forcing, solar panel controller, battery, fire, etc) and through which the site status is known in real time. The data are stored locally on the hard-disk and, at the same time, continuously transmitted by the SeedLink protocol to local acquisition/analysis nodes (Local Control Center) via Wireless LAN bridge. At each LCC site runs a linux Earthworm system which stores and manages the acquired data stream. The real-time analysis system will perform event detection and localization based on triggers coming from data-loggers and parametric information coming from the other LCCs. Once an event is detected, the system will performs automatic magnitude and focal mechanism estimations. In the immediate post-event period, the RISSC performs shaking map calculations using parameters from the LCCs and/or data from the event database. The recorded earthquake data are stored into an event database, to be available for distribution and visualization for further off-line analyses. The seismic network will be completed in two stages: • Deployment of 30 seismic stations along the southern Apennine chain (to date almost completed) • Setting up a carrier-class radio communication system for fast and reliable data transmission, and installation of 10 additional seismic stations.
    Beschreibung: Published
    Beschreibung: 325 - 341
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: reserved
    Schlagwort(e): Monitoring Infrastructure ; Early-warning Applications ; 04. Solid Earth::04.06. Seismology::04.06.03. Earthquake source and dynamics ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion ; 04. Solid Earth::04.06. Seismology::04.06.11. Seismic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 28
    Publikationsdatum: 2017-04-04
    Beschreibung: In this paper we integrate stratigraphic and sedimentological analyses of the volcaniclastic deposits, emplaced during initial opening and later widening of the Valle del Bove depression, with the available stratigraphy of the inner walls, and marine offshore data, structural data, and magnetic surveys to develop a comprehensive model for the opening of the Valle del Bove depression. The resulting model adds new insight into the triggering mechanisms of the flank collapse. Additionally, it suggests a three-stage evolution of the eastern flank of Etna. (1) About 10 Kyr ago, the extinct Ellittico volcano (60 80 (per uniformità anche con Acireale) to 15 Kyr) collapsed, forming the early Valle del Bove. The collapse produced an avalanche deposit that spread ESE and formed the base of the Milo Lahar and the Chiancone deposits. (2) The second stage involved instability-related minor collapses within the valley, causing southward and westward enlargement of the depression and the emplacement of the debris flow sequence that comprises the upper part of the Milo Lahar deposit. (3) Available debris that accumulated within the Valle del Bove from smaller subsequent collapses was deposited at the mouth of the Valle del Bove in the fluvial sequence that forms most of the exposed part of the Chiancone deposit. The emplacement of the whole volcaniclastic sequence occurred between 10 and 2 Kyr ago. Since then, the Valle del Bove has acted as a basin protecting the lower eastern flank of Etna from lava flows or inundations of volcaniclastic debris.
    Beschreibung: Published
    Beschreibung: 65-75
    Beschreibung: 3.5. Geologia e storia dei sistemi vulcanici
    Beschreibung: open
    Schlagwort(e): Etna ; flank collapse ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 29
    Publikationsdatum: 2017-04-04
    Beschreibung: The area of Serravalle, sited in the northern part of the town of Vittorio Veneto (TV), NE Italy, has been the target of a seismic microzonation campaign. 10 seismic stations have been deployed for a 7 months period to record in continuous mode. Three stations were installed on bedrock outcrops and seven on sedimentary sites with variable cover thickness. Spectral analyses have been performed on the collected data-set using the Generalized Inversion Technique (GIT, e.g. Andrews, 1986). In particular, spectral ratios have been calculated for each station relatively to the average of the three reference, bedrock sites. The spectral ratios provide quantitative estimates of the seismic motion amplifications which occur in each of the monitored sites. Two sites show high values of amplification, 5 times larger than signal amplitude at the reference sites, in correspondence of well discernible peak frequencies of 5 Hz. Results for the other stations show smaller amounts of site amplification spreading over a broad range of frequencies. Sites where the highest amplifications were recorded all lie on the left bank of the Meschio River and in areas farther away from its outlet into the plain correlating with the presence of thick layers of Quaternary deposits.
    Beschreibung: Published
    Beschreibung: 31-49
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): spectral ratios ; reference sites ; site effects ; earthquake grounf motion ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 30
    Publikationsdatum: 2017-04-04
    Beschreibung: Lava dome eruptions are commonly characterized by large fluctuations in discharge rate with cyclic behaviour on time-scales ranging from hours to decades. Examples include Bezymianny volcano (Russia), Merapi (Java), Santiaguito (Guatemala), Mt St Helens (USA), Mt Unzen (Japan), and Soufrie`re Hills volcano (Montserrat). Previous models have assumed simple cylindrical conduits for magma transport, but extrusions are mainly fed by dykes, with cylindrical geometries developing only at shallow levels. The widths of dykes embedded in an elastic medium are influenced by local magma pressure, affecting flow rates and system dynamics strongly. We develop a model for magma flow in dykes, which predicts intense pulsations of magma extrusion for the case of a constant source pressure. The period time scale is determined by the elastic deformation of the dyke walls and the length-to-width ratio of the dyke. The dyke acts like a volumetric capacitor, storing magma as pressure increases and then releasing magma in a pulse of extrusion. For the Soufrie`re Hills volcano, cyclic extrusions with time-scales of a few weeks are predicted for dykes 300–500 m long and 3–6 m wide, matching observations. The model explains the sharp onset of tilt pulsations and seismic swarms.
    Beschreibung: Published
    Beschreibung: L02303
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Control ; magma flow ; dykes ; cyclic lava ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.04. Thermodynamics
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 31
    Publikationsdatum: 2017-04-04
    Beschreibung: Hydrological and geochemical studies performed on Lake Specchio di Venere on Pantelleria island (Italy) indicate that this endorheic basin has been formed through upwelling of the water table, and that it is continuously fed by the thermal springs situated on its shores. The lake is periodically stratified both thermally and in salinity, albeit this stratification is rather unstable over time since meteorological events such as strong rain or wind can determine the mixing of its waters. Periodical analyses of the lake water chemistry show large variations of the salt content due to the yearly evaporation-rain dilution cycle. These processes are also responsible for the saline stratification during steady meteorological conditions. The mineralogical characterisation of the bottom sediments shows the almost exclusive presence of neoformation minerals, mainly carbonates, formed in response to the pH gradient between spring- (pH≈6) and lake-waters (pH≈9). Finally, the CO2 partial pressures in the lake water slightly exceeding the atmospheric one, are due to the large amounts of CO2 brought to the lake through the bubbling free gas phase of the thermal springs. Nevertheless the high pH value of the lake water, its small volume and its periodical mixing prevent dangerous built up of this gas.
    Beschreibung: Published
    Beschreibung: 1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Pantelleria island ; volcanic lake ; gas hazard ; 03. Hydrosphere::03.02. Hydrology::03.02.02. Hydrological processes: interaction, transport, dynamics ; 03. Hydrosphere::03.04. Chemical and biological::03.04.03. Chemistry of waters ; 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 32
    Publikationsdatum: 2017-04-04
    Beschreibung: A prototype system for earthquake early warning and rapid shake map evaluation is being developed and tested in southern Italy based on a dense, dynamic seismic network (accelerometers + seismometers) under installation in the Apenninic belt region (Irpinia Seismic Network). It can be classified as a regional Earthquake Early Warning System consisting of a broad-based seismic sensor network covering a portion or the entire area which is threatened by the quake's strike. The real time magnitude estimate will take advantage from the high spatial density of the network in the source region and the broad dynamic range of installed instruments. Based on the offline analysis of high quality strong-motion data bases recorded in Italy, several methods are envisaged, using different observed quantities (peak amplitude, dominant frequency, square velocity integral, …) to be measured on seismograms, as a function of time, both on P and early-S wave signals. Results from the analysis of the Italian strong motion database point out the possibility of using low-pass filtered displacement and velocity peak amplitudes measured in time windows lasting less than 3-4 sec after the first P- or S-wave arrivals. These parameters show they are robustly correlated with moment magnitude. The correlation found of 3Hz low-pass filtered PGV and PGD with magnitude is discussed and interpreted in terms of plausible dynamic models of the earthquake rupture process during its initial stage.
    Beschreibung: Published
    Beschreibung: 45-63
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: reserved
    Schlagwort(e): Real-time Estimation ; Magnitude ; Seismic Early Warning ; 04. Solid Earth::04.06. Seismology::04.06.03. Earthquake source and dynamics ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion ; 04. Solid Earth::04.06. Seismology::04.06.11. Seismic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 33
    Publikationsdatum: 2017-04-04
    Beschreibung: We applied a new simulation model, based on multiphase transport laws, to describe the 4D (3D spatial coordinates plus time) dynamics of explosive eruptions. Numerical experiments, carried out on a parallel supercomputer, describe the collapse of the volcanic eruption column and the propagation of pyroclastic density currents (PDCs), for selected medium scale (sub-Plinian) eruptive scenarios at Vesuvius, Italy. Simulations provide crucial insights into the effects of the generation mechanism of the flows - partial collapse vs boiling-over - on their evolution and hazard potential, the unstable dynamics of the fountain, and the influence of Mount Somma on the propagation of PDCs into the circum-Vesuvian area, one of the world's most hazardous volcanic settings. Results also show that it is possible to characterize the volcanic column behavior in terms of percentage of the mass of pyroclasts collapsed to the ground and how this parameter strongly influences the dynamics and hazard of the associated PDCs.
    Beschreibung: Published
    Beschreibung: L04309
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): explosive eruption ; numerical modeling ; Vesuvius ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 34
    Publikationsdatum: 2017-04-04
    Beschreibung: Field evidence reveals that the Neolithic village of Atlit-Yam (Israeli coast) was destroyed in an event which also caused the sudden death of tens of inhabitants. Archaeological evidence and numerical simulations support the notion that the village was destroyed, ~8.3 ka B.P., by a tsunami triggered by a known Holocene flank collapse of Mt. Etna volcano (Italy). The filling of a water well within the village confirms inundation by a tsunami wave train and a sediment layer, composed of a clayed-sandy matrix and other detritus including reworked marine sediment, indicates tsunami inundation. This scenario shows that tsunamis generated by sector collapses from coastal volcanoes can seriously threaten near-shore settlements thousands of kilometres distant from the tsunami source.
    Beschreibung: Published
    Beschreibung: L16317
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): tsunami ; Mt. Etna ; Atlit-Yam ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 35
    Publikationsdatum: 2017-04-04
    Beschreibung: Various authors, analysing the set of accelerograms recorded at Gubbio Piana (GBP) (central Italy), have demonstrated that strong amplification occurs at this accelerometric station, which is installed within an alluvial basin. In particular, Ambraseys et al. [(2005a), Bull Earthq Eng 3:1–53; (2005b), Bull Earth Eng 3:55–73] observed that the strong motion peaks at GBP greatly exceed the median values predicted by the attenuation relationships they derived for Europe. In this work, we analyse and discuss some characteristics of the ground motion recorded at the GBP station. We show that the ground motion parameters, such as peak-ground acceleration and peak-ground velocity, are strongly influenced by the presence of locally induced surface waves that produce both a lengthening of the significant shaking duration and an increase in the peak values with respect to a nearby bedrock site. The basin-induced surface waves are observed in the three components of motion and their effects on the peak values are particularly evident in the vertical component. In the frequency domain, the energy of the surface waves is mostly restricted to the frequency band 0.4–0.8Hz for both the horizontal and vertical components. The horizontal and vertical Fourier amplitudes are also very similar, and this indicates that the H/V spectral ratio technique is not applicable to describing the site response due to the propagation of seismic wave in a complex 2D/3D geological structure. Finally, a preliminary polarization analysis shows that the directions of polarization, as well as the degree of elliptical polarization, exhibit a strong variability with time, that may be related to a complex propagation of Love and Rayleigh waves within the basin.
    Beschreibung: Published
    Beschreibung: 27-43
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: JCR Journal
    Beschreibung: partially_open
    Schlagwort(e): site amplification ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 36
    Publikationsdatum: 2017-04-04
    Beschreibung: The use of a hand-held thermal camera during the 2002–2003 Stromboli effusive eruption proved essential in tracking the development of flow field structures and in measuring related eruption parameters, such as the number of active vents and flow lengths. The steep underlying slope on which the flow field was emplaced resulted in a characteristic flow field morphology. This comprised a proximal shield, where flow stacking and inflation caused piling up of lava on the relatively flat ground of the vent zone, that fed a medial–distal lava flow field. This zone was characterized by the formation of lava tubes and tumuli forming a complex network of tumuli and flows linked by tubes. Most of the flow field was emplaced on extremely steep slopes and this had two effects. It caused flows to slide, as well as flow, and flow fronts to fail frequently, persistent flow front crumbling resulted in the production of an extensive debris field. Channel-fed flows were also characterized by development of excavated debris levees in this zone (Calvari et al. 2005). Collapse of lava flow fronts and inflation of the upper proximal lava shield made volume calculation very difficult. Comparison of the final field volume with that expecta by integrating the lava effusion rates through time suggests a loss of ~70% erupted lava by flow front crumbling and accumulation as debris flows below sea level. Derived relationships between effusion rate, flow length, and number of active vents showed systematic and correlated variations with time where spreading of volume between numerous flows caused an otherwise good correlation between effusion rate, flow length to break down. Observations collected during this eruption are useful in helping to understand lava flow processes on steep slopes, as well as in interpreting old lava–debris sequences found in other steep-sided volcanoes subject to effusive activity.
    Beschreibung: Published
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Lava flow field ; Morphology ; Tumuli ; Lava tubes ; Effusion rate ; Rheology ; Stromboli volcano ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.07. Instruments and techniques ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 37
    Publikationsdatum: 2017-04-04
    Beschreibung: Numerical simulation of pyroclastic density currents has developed significantly in recent years and is increasingly applied to volcanological research. Results from physical modeling are commonly taken into account in volcanic hazard assessment and in the definition of hazard mitigation strategies. In this work, we modeled pyroclastic density currents in the Phlegrean Fields caldera, where flows propagating along the flat ground could be confined by the old crater rims that separate downtown Naples from the caldera. The different eruptive scenarios (mass eruption rates, magma compositions, and water contents) were based on available knowledge of this volcanic system, and appropriate vent conditions were calculated for each scenario. Simulations were performed along different topographic profiles to evaluate the effects of topographic barriers on flow propagation. Simulations highlighted interesting features associated with the presence of obstacles such as the development of backflows. Complex interaction between outward moving fronts and backflows can affect flow propagation; if backflows reach the vent, they can even interfere with fountain dynamics and induce a more collapsing behavior. Results show that in the case of large events ( 108 kg/s), obstacles affect flow propagation by reducing flow velocity and hence dynamic pressure in distal regions, but they cannot stop the advancement of flows. Deadly conditions (in terms of temperature and ash concentration) characterize the entire region invaded by pyroclastic flows. In the case of small events (2.5 107 kg/s), flows are confined by distal topographic barriers which provide valuable protection to the region beyond.
    Beschreibung: Published
    Beschreibung: Q11003
    Beschreibung: open
    Schlagwort(e): Phlegrean Fields ; multiphase flow ; pyroclastic flows ; dynamic pressure ; volcanic hazard ; caldera ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 38
    Publikationsdatum: 2017-04-04
    Beschreibung: The catastrophic events that occurred in May 1998 in the area of Sarno (Southern Italy) highlight the destructive potential of debris flows, even when they are of relatively low magnitude. More than 130 people were killed and severe property damage took place when volcaniclastic debris flows triggered by heavy rainfall inundated various towns located in piedmont areas. This work investigates the suitability of LAHARZ, a GIS-assisted method for the automatic delineation of lahar inundation areas, for reproducing the May 1998 flows at Sarno. It was found that recalibration of the empirical relationship employed by LAHARZ is required in order to realistically hind-cast the inundation areas of considered events. The potential for further improvements in prediction outputs for this type of geomorphic setting is discussed, taking into account the observed lower mobility of these small volcaniclastic debris flows as compared to lahars of similar size.
    Beschreibung: Published
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Sarno ; LAHARZ ; Debris flows ; Lahars ; Debris flow modelling ; Hazard assessment ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 39
    Publikationsdatum: 2017-04-04
    Beschreibung: An immersed boundary technique suitable for the solution of multiphase compressible equations of gas–particle flows of volcanic origin over complex 2D and 3D topographies has been developed and applied. This procedure combines and extends different existing methods designed for incompressible flows. Furthermore, the extension to compressible multiphase flows is achieved through a flux correction term in the mass continuity equations of the immersed cells that accounts for density variations in the partial volumes. The technique is computationally accurate and inexpensive, if compared to the use and implementation of the finite-volume technique on unstructured meshes. The first applications that we consider are the simulations of pyroclastic density currents generated by the collapse of a volcanic column in 2D axisymmetric geometry and by a dome explosion in 3D. Results show that the immersed boundary technique can significantly improve the description of the no-slip flow condition on an irregular topography even with relatively coarse meshes. Although the net effect of the present technique on the results is difficult to quantify in general terms, its adoption is recommended any time that cartesian grids are used to describe the large-scale dynamics of pyroclastic density currents over volcano topographies.
    Beschreibung: Published
    Beschreibung: 183-198
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Pyroclastic density currents ; Compressible flows ; Cartesian grids ; Finite-volume method ; Immersed boundary method ; Numerical simulation ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 40
    Publikationsdatum: 2017-04-04
    Beschreibung: The Campania Region (southern Italy) is characterized by the frequent occurrence of volcaniclastic debris flows that damage property and loss of life (more than 170 deaths between 1996 and 1999). Historical investigation allowed the identification of more than 500 events during the last four centuries; in particular, more than half of these occurred in the last 100 years, causing hundreds of deaths. The aim of this paper is to quantify debris-flow hazard potential in the Campania Region. To this end, we compared several elements such as the thickness distribution of pyroclastic fall deposits from the last 18 ka of the Vesuvius and Phlegrean Fields volcanoes, the slopes of relieves, and the historical record of volcaniclastic debris flows from A.D. 1500 to the present. Results show that flow occurrence is not only a function of the cumulative thickness of past pyroclastic fall deposits but also depends on the age of emplacement. Deposits younger than 10 ka (Holocene eruptions) apparently increase the risk of debris flows, while those older than 10 ka (Late Pleistocene eruptions) seem to play a less prominent role, which is probably due to different climatic conditions, and therefore different rates of erosion of pyroclastic falls between the Holocene and the Late Pleistocene. Based on the above considerations, we compiled a large-scale debris-flow hazard map of the study area in which five main hazard zones are identified: very low, low, moderate, high, and very high.
    Beschreibung: Published
    Beschreibung: 157-167
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: 5.4. TTC - Sistema Informativo Territoriale
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Debris flows ; Explosive eruptions ; Hazard mapping ; Vesuvius volcano ; Erosion ; Campania region ; Southern Italy ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 41
    Publikationsdatum: 2017-04-04
    Beschreibung: We present ground motion models for northwestern Turkey using the aftershocks of the Mw 7.4, 1999 Kocaeli earthquake. We consider 4047 velocity and acceleration records for each component of motion, from 528 earthquakes recorded by stations belonging to regional networks. The ground motion models obtained provide peak ground velocity, peak ground acceleration, and spectral accelerations for 8 different frequencies between 1 and 10 Hz. The analysis of the error distribution shows that the record-to-record component of variance is the largest contribution to the standard deviation of the calibrated ground- motion models. Furthermore, a clear dependence of inter-event error on stress drop is observed. The empirical ground-motion prediction equations, derived for both the larger horizontal and vertical components, are valid in the local magnitude range from 0.5 to 5.9, and for hypocentral distances up to 190 km. Citation: Bindi, D., S. Parolai, H. Grosser, C. Milkereit, and E. Durukal (2007), Empirical ground-motion prediction equations for northwestern Turkey using the aftershocks of the 1999 Kocaeli earthquake,
    Beschreibung: Published
    Beschreibung: L08305
    Beschreibung: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Beschreibung: JCR Journal
    Beschreibung: partially_open
    Schlagwort(e): Attenuation relationship ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 42
    Publikationsdatum: 2022-05-24
    Beschreibung: Various authors, analysing the set of accelerograms recorded at Gubbio Piana (GBP) (central Italy), have demonstrated that strong amplification occurs at this accelerometric station, which is installed within an alluvial basin. In particular, Ambraseys et al. [(2005a), Bull Earthq Eng 3:1–53; (2005b), Bull Earth Eng 3:55–73] observed that the strong motion peaks at GBP greatly exceed the median values predicted by the attenuation relationships they derived for Europe. In this work, we analyse and discuss some characteristics of the ground motion recorded at the GBP station. We show that the ground motion parameters, such as peak-ground acceleration and peak-ground velocity, are strongly influenced by the presence of locally induced surface waves that produce both a lengthening of the significant shaking duration and an increase in the peak values with respect to a nearby bedrock site. The basin-induced surface waves are observed in the three components of motion and their effects on the peak values are particularly evident in the vertical component. In the frequency domain, the energy of the surface waves is mostly restricted to the frequency band 0.4–0.8Hz for both the horizontal and vertical components. The horizontal and vertical Fourier amplitudes are also very similar, and this indicates that the H/V spectral ratio technique is not applicable to describing the site response due to the propagation of seismic wave in a complex 2D/3D geological structure. Finally, a preliminary polarization analysis shows that the directions of polarization, as well as the degree of elliptical polarization, exhibit a strong variability with time, that may be related to a complex propagation of Love and Rayleigh waves within the basin.
    Beschreibung: Published
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Strong motion ; Alluvial basin effects ; Site effects ; Gubbio plain ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 43
    Publikationsdatum: 2024-05-09
    Beschreibung: In January 2002, Nyiragongo volcano erupted 14–34 × 106 m3 of lava from fractures on its southern flanks. The nearby city of Goma was inundated by two lava flows, which caused substantial socioeconomic disruption and forced the mass exodus of the population, leaving nearly 120,000 people homeless. Field observations showed marked differences between the lava erupted from the northern portion of the fracture system and that later erupted from the southern part. These observations are confirmed by new 238U and 232Th series radioactive disequilibria data, which show the presence of three different phases during the eruption. The lavas first erupted (T1) were probably supplied by a residual magma batch from the lava lake activity during 1994–1995. These lavas were followed by a fresh batch erupted from fissure vents as well as later (May–June 2002) from the central crater (T2). Both lava batches reached the surface via the volcano's central plumbing system, even though a separate flank reservoir may also have been involved in addition to the main reservoir. The final phase (T3) is related to an independent magmatic reservoir located much closer (or even beneath) the city of Goma. Data from the January 2002 eruption, and for similar activity in January 1977, suggest that the eruptive style of the volcano is likely to change in the future, trending toward more common occurrence of flank eruptions. If so, this would pose a significant escalation of volcanic hazards facing Goma and environs, thus requiring the implementation of different volcano-monitoring strategies to better anticipate where and when future eruptions might take place.
    Beschreibung: Published
    Beschreibung: B09202
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Nyiragongo ; forecasting ; volcanic hazard ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 44
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    Unbekannt
    American Geophysical Union
    Publikationsdatum: 2017-04-04
    Beschreibung: A circular dome from Lipari Island consists of latitic enclaves hosted in a rhyolitic magma. A strain analysis of the enclaves has been carried out and the pure shear (a) and simple shear (g) deformation, the vorticity number Wk and flow kinematics are determined. The axial ratio Rf of the enclaves and the angle f between the long axis of the enclaves and the transport direction are measured in 131 sites concentrated in the axial zone (z1), upper-distal zone (z2) and basal zone (z3) of the flow. The f values depict a pattern suggesting endogenous growth. In z1, a/g 〉 1. In z2, 1 〈 a 〈 1.35 and 1.8 〈 g 〈 0.5. In z3, 1 〈 a 〈 1.5 and 0.3 〈 g 〈 2.8. In z1, Wk 〈 0.5. In z2 and z3, Wk 〉 0.8. Lateral stretching due to the upward motion of magma from the conduit prevails in z1. Here the increase of pure shear strain from the bottom to the top reflects strain accumulation due to endogenous growth. z2 and z3 suffer simple shear deformation. In z3, the sense of shear is consistent with the transport direction. An opposite sense of shear characterizes z2. This is due to velocity gradients located in the lower and upper portions of the flow. The kinematics is viscous spreading in z1 and viscous gliding (hyperbolic flow) in z2â z3.Possible rupturing of the exterior may be important in z1, where lateral stretching occurs, and in z3, where g is at a maximum. The effusion rate is 1.93 m3/s. Strain rates calculated using structural data span a range from 1.9 to 5.8.10 6 s 1.
    Beschreibung: Published
    Beschreibung: 1-10
    Beschreibung: partially_open
    Schlagwort(e): lava domes ; kinematics ; emplacement mechanism ; strain analysis ; enclaves ; viscous flows ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks
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  • 45
    Publikationsdatum: 2017-04-04
    Beschreibung: In winter 1998 a small-aperture (~200 m), four-station array was operating in the middle of the Colfiorito plain. Waveforms of seven small magnitude (2.1 〈 M 〈 3.7) local earthquakes are analyzed in this study. The peculiarity of the array seismograms is a 2-min long duration of the horizontal ground motion. The predominant frequency in the plain is around 1 Hz. In this frequency band, earthquake-induced ground shaking is synchronous for a few seconds during direct S waves; after this time window, wave trains show an increasingly chaotic behavior within the array. The energy variation of the horizontal ground shaking between the array and a nearby rock outcrop exceeds a factor of 500 at 1 Hz. In order to help understanding of observations and construct models for future numerical simulations, the buried structure of the Colfiorito plain has been investigated through seismic refraction profiles and geoelectric measurements. A three-dimensional reconstruction of the basin structure reveals an extremely complex bedrock topography, which is probably a recurrent feature for intermontane basins in tectonically active regions. Apparent velocities and backazimuths in the frequency band 0.5–1.5 Hz indicate that a 180-m deep depression NW of the array is responsible for the generation of edge-diffracted surface (Love) waves. Their arrival to the array breaks the synchronism of vertically reverberating waves which predominate in the first seconds of the S-wave window
    Beschreibung: Published
    Beschreibung: reserved
    Schlagwort(e): site effects ; 3-D basin resonance ; seismic array ; diffraction ; Colfiorito Basin ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
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  • 46
    Publikationsdatum: 2017-04-04
    Beschreibung: Ground-based measurements of volcanic sulfur dioxide fluxes are important indicators of volcanic activity, with application in hazard assessment, and understanding the impacts of volcanic emissions upon the environment and climate. These data are obtained by making traverses underneath the volcanic plume a few kilometers from source with an ultraviolet spectrometer, measuring integrated SO2 concentrations across the plume’s cross section, and multiplying by the plume’s transport speed. However, plume velocities are usually derived from ground-based anemometers, located many kilometers from the traverse route and hundreds of meters below plume altitude, complicating the experimental design and introducing large flux (can be 〉100%) errors. Here we present the first report of a single instrument capable of (accurate) volcanic SO2 flux measurements. This device records integrated SO2 concentrations and plume heights during traverses. Between traverses, two in-plume SO2 time series are measured from underneath the plume with the instrument, corresponding to zenith and inclined (user-specified angle from vertical in the direction of the volcano) fields of view, respectively. The distance between the points of intersection of the two views with the plume is found on the basis of the determined plume height, and the two signals are cross-correlated to determine the lag between them, enabling accurate derivation of the wind speed. We present flux data (with errors ±12%) obtained in this way at Mt. Etna during July 2004.
    Beschreibung: Published
    Beschreibung: Q02003
    Beschreibung: partially_open
    Schlagwort(e): DOAS ; volcanic SO2 emissions. ; 01. Atmosphere::01.01. Atmosphere::01.01.07. Volcanic effects ; 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::04.08.07. Instruments and techniques ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
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  • 47
    Publikationsdatum: 2017-04-04
    Beschreibung: From December 2002 to July 2003, Stromboli volcano was characterized by a new effusive stage of eruption after a period of extraordinary strombolian activity. Signals recorded in two continuous monitoring stations during the eruption, which have already been presented in very recent papers, evidenced anomalies in the CO2 flux just before the onset of the eruption. A more detailed analysis carried out on the data subset acquired during the eruption, integrated by daily field observations of the scientific personnel working at the volcanological observatory in Stromboli, showed that CO2 flux and soil temperature are strictly related to volcanic events. Furthermore, the relative minima and maxima of the two parameters showed a strong correlation with wind speed and direction. This fact was especially true at the summit station, whereas at the coastal sites seasonal and meteorological effects masked the volcanic signal. The analysis of the wind data, particularly the relationships between wind speed and direction, air and soil temperature, and local circulation of atmospheric air masses revealed that during the eruption, in the summit area of Stromboli air movements were not only related to atmospheric circulation but were also significantly affected, and in certain cases caused, by volcanic activity. This conclusion was reached by observing several anomalies, such as the discrepancies in the wind direction between the two stations, higher air temperatures at the summit site, and inversion of direction for wind before and after the reopening of the conduit in a major explosion on 5 April 2003. The relationships found between volcanic activity, soil temperatures, CO2 fluxes, and wind speed and direction indicate that soil temperature measurements, in an open conduit volcano such as in this case, could be used to monitor the level of volcanic activity, along with CO2 flux. Furthermore, the possible volcanic origin of a peculiar type of air circulation identified in the summit area of Stromboli suggests that the separation between volcanic and atmospheric signals might not be obvious, requiring monitoring over a wide area, rather than a single location.
    Beschreibung: Published
    Beschreibung: Q12001
    Beschreibung: partially_open
    Schlagwort(e): carbon dioxide flux ; continuous monitoring ; soil temperature ; wind ; 01. Atmosphere::01.01. Atmosphere::01.01.07. Volcanic effects ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 05. General::05.02. Data dissemination::05.02.03. Volcanic eruptions ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
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  • 48
    Publikationsdatum: 2017-04-04
    Beschreibung: Marked increases of CO2, H2 and He dissolved in thermal waters and changes in the dissolved carbon isotopic composition, were observed at Stromboli before the 28 December 2002 eruption and before a violent explosive paroxysm occurred on 5 April 2003. High anomalous CO2 flux values were recorded at the crater rim since a week before the eruption onset. The first anomalies in the thermal waters (dissolved CO2 amount) appeared some months before the eruption, when magma column rose at a very high level in the conduit. High peaks of dissolved H2 and He were recorded a few days before the paroxysm. Carbon isotopic composition indicates a magmatic origin of the dissolved CO2 whose increase, together with those of H2 and He, is attributed to an increasing output of deep gases likely produced by depressurization of a rising batch of a deep gas-rich magma, whose fragments have been emitted during the explosion.
    Beschreibung: Italian Civil Protection
    Beschreibung: Published
    Beschreibung: L07620
    Beschreibung: partially_open
    Schlagwort(e): Stromboli ; geochemical precursors ; CO2 flux ; pH ; 03. Hydrosphere::03.04. Chemical and biological::03.04.03. Chemistry of waters ; 03. Hydrosphere::03.04. Chemical and biological::03.04.05. Gases ; 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 ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
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  • 49
    Publikationsdatum: 2017-04-04
    Beschreibung: Flank instability and collapse are observed at many volcanoes. Among these, Mt. Etna is characterized by the spreading of its eastern and southern flanks. The eastern spreading area is bordered to the north by the EW-trending Pernicana Fault System (PFS). During the 20022003 Etna eruption, ground fracturing along the PFS migrated eastward from the NE Rift, to as far as the 18 km distant coastline. The deformation consisted of dextral en-echelon segments, with sinistral and normal kinematics. Both of these components of displacement were one order of magnitude larger (~1 m) in the western, previously known, portion of the PFS with respect to the newly surveyed (~9 km long) eastern section (~0.1 m). This eastern section is located along a pre-existing, but previously unknown, fault, where displaced man-made structures give overall slip rates (11.9 cm/year), only slightly lower than those calculated for the western portion (1.42.3 cm/year). After an initial rapid motion during the first days of the 20022003 eruption, movement of the western portion of the PFS decreased dramatically, while parts of the eastern portion continued to move. These data suggest a model of spreading of the eastern flank of Etna along the PFS, characterized by eruptions along the NE Rift, instantaneous, short-lived, meter-scale displacements along the western PFS and more long-lived centimeter-scale displacements along the eastern PFS. The surface deformation then migrated southwards, reactivating, one after the other, the NNWSSE-trending Timpe and Trecastagni faults, with displacements of ~0.1 and ~0.04 m, respectively. These structures, along with the PFS, mark the boundaries of two adjacent blocks, moving at different times and rates. The new extent of the PFS and previous activity over its full length indicate that the sliding eastern flank extends well below the Ionian Sea. The clustering of seismic activity above 4 km b.s.l. during the eruption suggests a deep décollement for the moving mass. The collected data thus suggests a significant movement (volume 〉1,100 km3) of the eastern flank of Etna, both on-shore and off-shore.
    Beschreibung: Published
    Beschreibung: 417-430
    Beschreibung: partially_open
    Schlagwort(e): Volcano spreading ; Fracturing ; Mt. Etna ; Pernicana Fault System ; NE Rift ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 05. General::05.02. Data dissemination::05.02.03. Volcanic eruptions ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
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  • 50
    Publikationsdatum: 2017-04-04
    Beschreibung: We have characterized pumice products belonging to the climactic phase of the 800-year-b.p. Quilotoa eruption. Bulk rock compositions, petrography, mineral, and glass chemistry and textural investigations were performed on the three end-member pumice types, namely white, gray, and mingled pumices. All the investigated pumice clasts are dacites characterized by the same bulk rock composition and mineralogical assemblage, but glass compositions and bulk textures change according to different pumice types. White pumice has higher crystallinity (~48 wt%), abundant euhedral pheno/microphenocrysts, no groundmass microlites, the most evolved glass compositions (7478 wt% SiO2), and heterogeneous vesicle populations marked by deformed and highly coalesced vesicles with thin walls. Gray pumice exhibits lower crystallinity (2936 wt%), abundant broken and/or resorbed crystals, ubiquitous groundmass phenocryst fragments and microlites, the widest range of glass compositions (6978 wt% SiO2), and quite homogeneous poorly deformed and coalesced vesicles with thicker walls. Mingled pumices are characterized by the alternation of bands or patches with white and gray pumice compositional and textural characteristics. We attribute heterogeneities in glass compositions and crystal and vesicle textures to processes occurring within volcanic conduits as magma is ascending to the surface. In particular, the above observations and results are consistent with an origin of a gray magma by heating of the original white magma in a strongly sheared region of the conduit because of a mechanism of viscous dissipation and crystal grinding and resorption at the conduit walls. The less viscous gray magma, therefore, would enable the onset and preservation of a high mass flux of the eruption otherwise difficult to explain for highly viscous crystal-rich dacitic magmas.
    Beschreibung: Published
    Beschreibung: 307-321
    Beschreibung: partially_open
    Schlagwort(e): Plinian eruption ; Crystal-rich magma ; Crystal grinding ; Pumice types ; Viscous dissipation ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 05. General::05.02. Data dissemination::05.02.03. Volcanic eruptions
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  • 51
    Publikationsdatum: 2017-04-04
    Beschreibung: On 2nd/3rd November 2002, a huge amount of gas, mainly composed of CO2, was suddenly released from the sea bottom off the coast of Panarea, producing a ‘‘crater’’20 by 10 meters wide and 7 meters deep. The gas output was estimated to be 109 l/d, two orders of magnitude higher than that measured in the 1980s. The anomalous degassing rate lasted for some weeks, slowly decreasing to an almost constant rate of about 4 x 107 l/d after two months. The geothermo- barometric estimations revealed an increase of both the temperature and pressure in the geothermal system feeding the sampled vents. The 3He/4He ratios were similar to those measured in nearby Stromboli. We have monitored the area for the last two decades, and based on our intensive and extensive geochemical measurements, have ascertained that the geothermal reservoir has lost its steady state. We maintain that a new magmatic input caused these phenomena.
    Beschreibung: - Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Vesuviano, Naples, Italy. - Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Palermo, Palermo, Italy. - Dipartimento Chimica e Fisica della Terra ed Applicazioni, Palermo, Italy.
    Beschreibung: Published
    Beschreibung: L07619
    Beschreibung: partially_open
    Schlagwort(e): Submarine degassing ; magmatic fluids ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.04. Thermodynamics ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 05. General::05.02. Data dissemination::05.02.01. Geochemical data ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk
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  • 52
    Publikationsdatum: 2017-04-04
    Beschreibung: Five gas discharges in the area of Mount Etna volcano (Italy) and in the near Hyblean plateau have been monitored since 1996. All the emissions displayed low contributions from crustal fluids, whereas magmatic gases were the main component. Selective dissolution of these gases into hydrothermal aquifers has been recognized and modeled, allowing us to calculate the original composition of the magma-released gases. The inferred composition of the magmatic gases exhibits synchronous variations of He/Ne and He/CO2 ratios, which are coherent with the magma degassing process. On the basis of numerical simulations of volatile degassing from Etnean basalts we have computed the initial and final pressures of the magma batches feeding the emissions. We thus can define the levels of the Etna plumbing system where magmas are stored. Pressure values were around 360 and 160 MPa for initial and final stages, respectively, meaning related depths of about 10 and 3 km below sea level, matching those obtained by geophysical investigations for the deep and shallow magma reservoirs. In addition, we have been able to recognize episodes of magma migration from the deeper reservoir toward the shallow one. An important magma injection into the shallow storage volume was detected during the onset of the 2001 eruption (17 July). No further injection had taken place during this period until September 2001, providing a possible reason for the quick exhaustion of the eruption. In view of this we suggest that the sampled emissions are a powerful geochemical tool to investigate the Etna’s plumbing system and its magma dynamics, as well as the development of eruptive events.
    Beschreibung: Published
    Beschreibung: 2463
    Beschreibung: partially_open
    Schlagwort(e): gas geochemistry ; magma degassing ; modeling ; 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::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.04. Thermodynamics ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
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  • 53
    Publikationsdatum: 2017-04-04
    Beschreibung: Five years of gas monitoring from selected sites suggest that Mt Etna’s plumbing system is much more extensive than previously reported. It extends at least 40 km SW from the volcano’s boundary along the NE-SW regional fault, where it discharges about 200 tons/day of gas, containing helium with mantle-type isotopic composition. Synchronous variations of 3He/4He isotopic ratios in gas sampled at sites located 60 kilometers apart have allowed us to detect pulses of ascending magma in the plumbing system, thus providing a powerful tool for eruption forecasting. Following summer 2001 eruption, the still increasing trend of the 3He/4He ratios indicates that magma storage is even now occurring at a shallow depth. Hence, the volcano maintains a high capacity to re-erupt within the next few months.
    Beschreibung: Published
    Beschreibung: 1057
    Beschreibung: partially_open
    Schlagwort(e): helium isotopes ; geochemical monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
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