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  • 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks  (20)
  • 01. Atmosphere::01.02. Ionosphere::01.02.06. Instruments and techniques  (16)
  • Etna
  • Elsevier Science Limited  (40)
  • Nature Publishing Group  (5)
  • Elsevier Scientific Publishers  (2)
  • American Chemical Society
  • American Chemical Society (ACS)
  • Molecular Diversity Preservation International
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  • 1
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    Geochemistry of the mantle source and magma feeding system beneath Turrialba volcano, Costa Rica (2016)
    Elsevier Science Limited
    Details
    Publikationsdatum: 2020-10-29
    Beschreibung: Turrialba volcano lies in the southern sector of the Central American Volcanic Front (CAVF) in Costa Rica. The geochemistry of major and trace elements, and Sr and Nd isotopes of a selected suite of volcanic rocks ranging in composition from basaltic andesite to dacite and belonging to the last 10 ka of activity of Turrialba volcano is described, together with the He-, Ne-, and Ar-isotope compositions of fluid inclusions hosted in olivine and pyroxene crystals. Most of the variability in the rock chemistry is consistentwith typical trends of fractional crystallization, but there is an outlying group of andesites that displays an adakite-like composition (with a consistent depletion in high-field-strength elements and a marked enrichment in Sr) and low 3He/4He ratios (7.0–7.2 Ra). The trace-element composition of these rocks is typical of subduction-related magmas influenced by an OIB-like component at the source associated with the subduction of the Galapagos seamounts. The 87Sr/86Sr (0.703612–0.703678) and 143Nd/144Nd (0.512960–0.512984) ratios of the bulk rocks vary within narrowranges, and are among the least-radiogenic isotope signatures of the CAVF volcanoes. The 3He/4He ratios measured in fluid inclusions hosted in olivine crystals (up to 8.1 Ra) are among the highest for the CAVF, and indicate that radiogenic 4He from fluids derived fromthe subducting slab contribute negligibly to the mantle wedge. The difference in He isotopes between most of studied rocks and those showing adakite-like features reasonably reflects two distinct components in the local mantle: (1) a MORB-like component, characterized by the highest He-isotope ratios (7.8–8.1 Ra), and (2) an OIB-like component, characterized by lower He-isotope ratios (7.0–7.2 Ra), coming from the subduction of the Galapagos seamounts. An overview at the regional scale indicates that high He-isotope ratios are peculiar to the two extreme sectors of the CAVF (Costa Rica to the south and Guatemala to the north), whereas in the central sector (Nicaragua) the magma source is probably contaminated by slab fluids. For the past few years Turrialba volcano has been in a volcanic unrest phase that has included a series of explosions, the most recent of which occurred between October 2014 and May 2015. The volcano is subject to an ongoing safety alert due to the possibility of a magmatic eruption. One of the crucial questions to be addressed is the kind of eruption that can be expected, and hence what type of magma is likely to be involved. The high 3He/4He ratios (7.8–8.0 Ra) measured during 2011 at high-temperature fumaroles of Turrialba craters are comparable to those measured in fluid inclusions of basaltic andesites that erupted in 1864–1866, suggesting that the magma currently feeding the shallow plumbing system has similar geochemical characteristics to the most recently erupted magma.
    Beschreibung: Published
    Beschreibung: 319-335
    Beschreibung: 1V. Storia e struttura dei sistemi vulcanici
    Beschreibung: 2V. Dinamiche di unrest e scenari pre-eruttivi
    Beschreibung: JCR Journal
    Beschreibung: restricted
    Schlagwort(e): Turrialba ; 3He/4He ratio ; Fluid inclusions ; Adakite ; MORB mantle ; OIB mantle ; 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::04.04. Geology::04.04.12. Fluid Geochemistry ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 2
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    A new set of standards for in–situ measurement of bromine abundances in natural silicate glasses: Application to SR-XRF, LA-ICP-MS and SIMS techniques (2017)
    Elsevier Science Limited
    Details
    Publikationsdatum: 2020-12-17
    Beschreibung: Measuring the low bromine abundances in Earth's materials remains an important challenge in order to constrain the geodynamical cycle of this element. Suitable standard materials are therefore required to establish reliable analytical methods to quantify Br abundances. In this study we characterise 21 Br-doped glasses synthesized from natural volcanic rocks of mafic to silicic compositions, in order to produce a new set of standards for Br analyses using various techniques. The nominal Br contents (amounts of Br loaded in the experimental samples) of 15 of 21 glasses were confirmed within 20% by instrumental neutron activation analysis (INAA). Using this newset of standards, we compare three micro-analytical approaches to measure Br contents in silicate glasses: synchrotron X-ray fluorescence (SR-XRF), laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS), and secondary ion mass spectrometry (SIMS). With SR-XRF, the Br contents of the standard glasses were determined with the highest accuracy (b10% for Br ≥ 10 ppm; N25% for Br ≤ 5 ppm), and high precision (b10% for Br contents N10 ppm; 20–30% for Br ≤ 10 ppm). The detection limit was estimated to be b1 ppm Br. All those factors combined with a high spatial resolution (5 × 5 μm for the presented measurements), means that SR-XRF iswell suited to determine the lowBr abundance in natural volcanic glasses (crystal-hosted melt inclusions or matrix glasses of crystallized samples). At its current stage of development, the LA-ICP-MS method allows the measurement of hundreds to thousands ppm Br in silicate glasses with a precision and accuracy generally within 20%. The Br detection limit of this method has not been estimated but its low spatial resolution (90 μm) currently prevents its use to characterise natural volcanic glasses, however it is fully appropriate to analyse super liquidus or sparsely phyric, Br-rich experimental charges. Our study shows that SIMS appears to be a promising technique to measure the lowBr contents of natural volcanic glasses. Its spatial resolution is relatively good (~15 μm) and, similarly to SR-XRF, the detection limit is estimated to be ≤ 1 ppm. Using our new set of standards, the Br contents of two MPI-DING reference glasses containing ≤ 1.2 ppm of Br were reproduced with precision b5% and accuracy b20%. Moreover, SIMS presents the advantage of being a more accessible instrument than SR-XRF and data processing is more straightforward.
    Beschreibung: Published
    Beschreibung: 60-70
    Beschreibung: 2V. Dinamiche di unrest e scenari pre-eruttivi
    Beschreibung: JCR Journal
    Beschreibung: restricted
    Schlagwort(e): bromine ; rock standards ; 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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  • 3
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    The effect of CO2 and H2O on Etna and Fondo Riccio (Phlegrean Fields) liquid viscosity, glass transition temperature and heat capacity (2015)
    Elsevier Science Limited
    Details
    Publikationsdatum: 2020-12-18
    Beschreibung: Viscosity (η), glass transition (Tg) and heat capacity (Cp) of Etna trachybasalt and Fondo Riccio latite (Phlegrean Fields, Italy)were determined at lowand high temperatures for dry, hydrous and CO2 bearing samples.High temperature experiments have been performed in the range of 1499 to 1700 K by concentric cylindermeasurements, while low temperature experiments were carried out in the interval between 633 and 1093 K using the micropenetration technique. Glass transition temperature and glassy and liquid heat capacitieswere investigated using differential scanning calorimetry (DSC) up to 955 K. The H2O content in themelts ranged from nominally dry to 6.32 wt.%, while CO2 ranged from 229 to 1907 ppm. We combined low- and high-temperature viscosities and parameterized them by the use of a modified Vogel– Fulcher–Tamman equation,which accommodates the non-Arrhenian temperature dependence ofmelt viscosity. Experimental measurements showthat melt viscosity decreaseswith increasing temperature and water and CO2 contents. For latitic samples at 893 K, the introduction of CO2 (up to 732 ppm) decreases the liquid viscosity up to one order of magnitude with respect to the measured viscosity for H2O-bearing liquid. Moreover, the results of calorimetric measurements indicate that the glass transition temperature decreaseswith increasing volatile content (H2O+CO2). The glass transition temperature decreases by about 25 K by adding up to 1907 ppmof CO2 in the trachybasaltic samples. No appreciable effect on glassy [Cpg (Tg)] and liquid (Cpliq) heat capacities was observed with the addition of water and CO2. Structural and volcanological implications (i.e. volatile speciation and melt fragility) for water and CO2 dissolution in silicate melts are discussed in light of the presented results.
    Beschreibung: Published
    Beschreibung: 72-86
    Beschreibung: 3V. Dinamiche e scenari eruttivi
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Viscosity ; glass transition ; Etna ; Phlegrean Fields ; volatiles ; 04. Solid Earth::04.08. Volcanology::04.08.02. Experimental volcanism
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 4
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    Automatic ionospheric layers detection: Algorithms analysis (2016)
    Elsevier Science Limited
    Details
    Publikationsdatum: 2021-01-27
    Beschreibung: Vertical sounding is a widely used technique to obtain ionosphere measurements, such as an estimation of virtual height versus frequency scanning. It is performed by high frequency radar for geophysical applications called "ionospheric sounder” (or "ionosonde”). Radar detection depends mainly on targets characteristics. While several targets behavior and correspondent echo detection algorithms have been studied, a survey to address a suitable algorithm for ionospheric sounder has to be carried out. This paper is focused on automatic echo detection algorithms implemented in particular for an ionospheric sounder, target specific characteristics were studied as well. Adaptive threshold detection algorithms are proposed, compared to the current implemented algorithm, and tested using actual data obtained from the Advanced Ionospheric Sounder (AIS-INGV) at Rome Ionospheric Observatory. Different cases of study have been selected according typical ionospheric and detection conditions.
    Beschreibung: Published
    Beschreibung: 1360-1372
    Beschreibung: 2A. Fisica dell'alta atmosfera
    Beschreibung: JCR Journal
    Beschreibung: restricted
    Schlagwort(e): ionogram ; layer detection ; adaptive threshold ; 01. Atmosphere::01.02. Ionosphere::01.02.06. Instruments and techniques
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 5
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    Intersection of exogenous, endogenous and anthropogenic factors in the Holocene landscape: A study of the Naples coastline during the last 6000 years (2013)
    Elsevier Science Limited
    Details
    Publikationsdatum: 2021-07-14
    Beschreibung: New data on the ancient landscape of Naples (southern Italy) during the middle and late Holocene from geo-archaeological excavations associated with public transport works were used to reconstruct the hill and coastal environment to the west of the ancient Graeco-Roman polis, where remains of human settlements date to the late Neolithic. The rich stratigraphic and archaeological records that emerged from the digs and from previous boreholes were measured and analysed by combining sedimentary facies analysis, tephrostratigraphy and archaeological data. Between the 5th and 4th millennia BP, a rocky profile with a wave-cut platform cutting across pyroclastites emplaced from the surrounding volcanoes was predominant in the coastal landscape. During the 3rd millennium BP, this rocky coast was progressively replaced by a sandy littoral environment primarily due to marine deposition, with a coastline located some hundred meters inland with respect to the modern one. The sedimentary record of the Greek and Roman periods indicates short-term fluctuations of the coastline, leading to the establishment of a backshore environment towards the end of the 6th century AD, when prograding river mouths and lobes of debris flows contributed to the advancing trend of the shoreline. The frequent archaeological remains from these periods indicate a stable settled area since Roman times. The shoreline was still subject to short-lived fluctuations between the 12th and 16th centuries, and attained its present position during the modern era with man-made reshaping of its profile. The construction of Relative Sea Level curves for two coastal sites reveals that the persistence of the foreshore environment in the Naples coastal strip during the 5th and 4th millennia BP was controlled by the counterbalancing effect of either the concurrent eustatic sea level rise or subsidence. On the other hand, the morpho-stratigraphic record for the last two millennia shows a significant correlation between sedimentation rate and settlement history, accounting for the dominant role of the anthropogenic forcing-factor in late Holocene landscape history. In particular, land mismanagement during Late Antiquity seems to have triggered a slope disequilibrium phase, exacerbating soil erosion and increasing the sediment accumulation rate in both foothill and coastal areas. Nonetheless, the environmental changes of the Chiaia coast during the last 2000 years clearly show volcanicetectonic perturbations influencing coastline development up to the modern era.
    Beschreibung: Published
    Beschreibung: 107-119
    Beschreibung: 3.5. Geologia e storia dei vulcani ed evoluzione dei magmi
    Beschreibung: 3.10. Storia ed archeologia applicate alle Scienze della Terra
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): study ; Naples coastline ; the last 6000 years ; 04. Solid Earth::04.04. Geology::04.04.03. Geomorphology ; 04. Solid Earth::04.04. Geology::04.04.10. Stratigraphy ; 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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  • 6
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    Geological, seismological and geodetic evidence of active thrustingand folding south of Mt. Etna (eastern Sicily): Revaluation of “seismicefficiency” of the Sicilian Basal Thrust (2016)
    Elsevier Science Limited
    Details
    Publikationsdatum: 2021-03-12
    Beschreibung: tGeological studies and morphological analysis, compared with seismological and geodetic data, suggestthat a compressive regime currently occurs at crustal depth in the western sector of Mt. Etna, accommo-dated by shallow thrusting and folding at the front of the chain, south of the volcanic edifice. In particular,a large WSW-ENE trending anticline, interpreted as detachment fold, is growing west and north of Cata-nia city (the Catania anticline). Geological data suggest that during the last 6000 years the frontal foldhas been characterized by uplift rates of ∼6 mm/yr along the hinge, consistent with the interferometricdata (10 mm/yr) recorded in the last 20 years. Moreover, a NNW-SSE oriented axis of compression hasbeen obtained by seismological data, consistent with GPS measurements over the last 20 years whichhave revealed a shortening rate of ∼5 mm/yr along the same direction. Besides the activity related to thevolcanic feeding system, the seismic pattern under the Mt. Etna edifice can be certainly related to theregional tectonics. The compressive stress is converted into elastic accumulation and then in earthquakesalong the ramps beneath the chain, whereas on the frontal area it is accommodated by aseismic defor-mation along an incipient detachment within the clayish foredeep deposits. The high rate of shorteningat the aseismic front of the chain, suggests a greater “seismic efficiency” in correspondence of ramps atthe rear.
    Beschreibung: Published
    Beschreibung: 32-41
    Beschreibung: 2T. Tettonica attiva
    Beschreibung: JCR Journal
    Beschreibung: restricted
    Schlagwort(e): Etna ; sicilian basal thrust ; 04. Solid Earth::04.04. Geology::04.04.01. Earthquake geology and paleoseismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 7
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    Revealing magma degassing below closed-conduit active volcanoes: Geochemical features of volcanic rocks versus fumarolic fluids at Vulcano (Aeolian Islands, Italy) (2016)
    Elsevier Science Limited
    Details
    Publikationsdatum: 2021-03-11
    Beschreibung: The elemental and isotopic compositions of noble gases (He, Ne, and Ar) in olivine- and clinopyroxene-hosted fluid inclusions have been measured for rocks at various degrees of evolution and belonging to high-K calcalkaline–shoshonitic and shoshonitic–potassic series in order to cover the entire volcanological history of Vulcano Island (Italy). The major- and trace-element concentrations and the Sr- and Pb-isotope compositions forwhole rockswere integratedwith data obtained fromthe fluid inclusions. 3He/4He in fluid inclusions iswithin the range of 3.30 and 5.94 R/Ra, being lower than the theoretical value for the deepmagmatic source expected for Vulcano Island (6.0–6.2 R/Ra). 3He/4He of themagmatic source is almost constant throughout the volcanic history of Vulcano. Integration of the He- and Sr-isotope systematics leads to the conclusion that a decrease in the Heisotope ratio of the rocks is mainly due to the assimilation of 10–25% of a crustal component similar to the Calabrian basement. 3He/4He shows a negative correlationwith Sr isotopes except for the last-erupted Vulcanello latites (Punta del Roveto),which have anomalously high He isotope ratios. This anomaly has been attributed to a flushing process by fluids coming from the deepest reservoirs, since an input of deep magmatic volatiles with high 3He/4He values increases the He-isotope ratio without changing 87Sr/86Sr. A comparison of the He-isotope ratios between fluid inclusions and fumarolic gases shows that only the basalts of La Sommata and the latites of Vulcanello have comparable values. Taking into account that the latites of Vulcanello relate to one of the most-recent eruptions at Vulcano (in the 17th century), we infer that the most probable magma which actually feeds the fumarolic emissions is a latitic body that ponded at about 3–3.5 km of depth and is flushed by fluids coming from a deeper and basic magma.
    Beschreibung: Published
    Beschreibung: 272-287
    Beschreibung: 1V. Storia e struttura dei sistemi vulcanici
    Beschreibung: JCR Journal
    Beschreibung: restricted
    Schlagwort(e): Helium isotopes, Fluid inclusions ; 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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  • 8
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    20 March 2015 solar eclipse influence on sporadic E layer (2015)
    Elsevier Science Limited
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    Publikationsdatum: 2021-06-07
    Beschreibung: This paper shows how the solar eclipse occurred on 20 March 2015 influenced the sporadic E (Es) layer as recorded by the Advanced Ionospheric Sounder by Istituto Nazionale di Geofisica e Vulcanologia (AIS-INGV) ionosondes installed at Rome (41.8°N, 12.5°E) and Gibilmanna (37.9°N, 14.0°E), Italy. In these locations, the solar eclipse was only partial, with the maximum area of the solar disk obscured by the Moon equal to ~54% at Rome and ~45% at Gibilmanna. Nevertheless, it is shown that the strong thermal gradients that usually accompany a solar eclipse, have significantly influenced the Es phenomenology. Specifically, the solar eclipse did not affect the Es layer in terms of its maximum intensity, which is comparable with that of the previous and next day, but rather in terms of its persistence. In fact, both at Rome and Gibilmanna, contrary to what typically happens in March, the Es layer around the solar eclipse time is always present. On the other hand, this persistence is also confirmed by the application of the height–time–intensity (HTI) technique. A detailed analysis of isoheight ionogram plots suggests that traveling ionospheric disturbances (TIDs) likely caused by gravity wave (GW) propagation have played a significant role in causing the persistence of the Es layer.
    Beschreibung: Published
    Beschreibung: 2064–2072
    Beschreibung: 1A. Geomagnetismo e Paleomagnetismo
    Beschreibung: 2A. Fisica dell'alta atmosfera
    Beschreibung: 1IT. Reti di monitoraggio e Osservazioni
    Beschreibung: JCR Journal
    Beschreibung: restricted
    Schlagwort(e): Mid-latitude ionosphere ; E sporadic layer ; Solar eclipse ; Gravity wave ; Height–time–intensity technique ; 01. Atmosphere::01.02. Ionosphere::01.02.99. General or miscellaneous ; 01. Atmosphere::01.02. Ionosphere::01.02.04. Plasma Physics ; 01. Atmosphere::01.02. Ionosphere::01.02.05. Wave propagation ; 01. Atmosphere::01.02. Ionosphere::01.02.06. Instruments and techniques ; 05. General::05.07. Space and Planetary sciences::05.07.01. Solar-terrestrial interaction
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 9
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    Interaction between particles transported by fallout and surge in the deposits of the Agnano-Monte Spina eruption (Campi Flegrei, Southern Italy) (2006)
    Elsevier Scientific Publishers
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: The Agnano^Monte Spina Tephra (AMST) is a complex sequence of beds generated by contrasting fragmentation and transportation dynamics. The 4.1 ka eruption was accompanied by a volcano-tectonic collapse, part of which is the present Agnano plain. The pyroclastic sequence is subdivided into members and submembers, each characterized by different lithological and sedimentological features. Plinian/subplinian fallout deposits frequently alternate with base-surge beds of phreatomagmatic origin. Analysis of lateral facies variations and vertical facies associations of correlated layers of submembers B2, D2 and E2 reveals that during some eruption phases the contrasting eruptive dynamics were almost contemporaneous. Base-surge deposits of submember B2 formed during the declining stage of a plinian column. They resulted from highly energetic and steady pyroclastic density currents that traveled long distances from the vent area and surmounted topographic obstacles such as the Posillipo hill (V150 m) and the northern sector of the Camaldoli hill (V250 m). Submember D2 pyroclastic density currents formed when contemporaneous fallout from an eruptive column was present. Coarse particles from the column settled throughout the pyroclastic density current, determining a significant increase of the solid load of the base surge. The consequent increase of supply rate from the transportation to the depositional zone of the base surge led to the formation of unsteady flows that could not efficiently transport the solid load and did not have the ability to travel long distances. Base-surge deposits of submember E2 were fed by a pulsating phreatomagmatic activity, which was punctuated by a short-lived fallout phase. Fallout material, which was incorporated as an additional load to the base surges, was partially transported by low-energy, steady pyroclastic density currents that traveled over the Agnano plain but did not surmount either the Camaldoli or the Posillipo hills. Only the very fine material, in continuous suspension in the upper, no-shearing part of the base-surge cloud, was dispersed higher in the atmosphere and quietly settled over a large area outside the caldera rim. The phreatomagmatic origin of base surges, which contrasts with the magmatic origin of fallout activity, suggests that the pyroclastic density currents of the Agnano^Monte Spina eruption did not result from eruption column collapses. They were most likely related to radially spreading clouds which were contemporaneous with fallout activity but issued from distinct zones in the vent area. The turbulent nature and the high expansion of base surges made them capable, under certain conditions, of passing over high topographic obstacles, with hazardous effects in distal areas.
    Beschreibung: Published
    Beschreibung: 193-210
    Beschreibung: partially_open
    Schlagwort(e): base-surge deposits ; Campi Flegrei ; phreatomagmatism ; fallout deposits ; 04. Solid Earth::04.04. Geology::04.04.08. Sediments: dating, processes, transport ; 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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  • 10
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    Turbulent boundary layer shear flows as an approximation of base surges at Campi Flegrei (Southern Italy) (2006)
    Elsevier Scientific Publishers
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: Small-volume base-surge deposits of Astroni and Agnano^Monte Spina eruptions at Campi Flegrei consist of sets of beds formed by the passage of multiple pyroclastic density currents. Each set is made by a fining-upward sequence consisting, from base to top,of : (1) an inversely graded layer made of bombs and lapilli; (2) a finely laminated layer with wavy bedforms made of coarse ash and fine lapilli; (3) a structureless fine-ash bed. Lack of discontinuities at layer contacts allows us to hypothesize that each set of beds represents the passage of one pyroclastic density current. The sequence formed as a function of the decreasing particle transportation capability of the base surge during the waxing^sustained^waning phases of flowage. We make the simplifying assumptions that the flow,on passing from the deposition of the inversely graded layer to the deposition of the finely laminated layer,had low particle concentration,was quasi-steady and incompressible. By such assumptions,some of the equations that regulate sediment mechanics are applicable to the base surges of Campi Flegrei to reconstruct flow density and shear velocity in between the deposition of the two layers. Structural and textural features of deposits stress the importance of shear and turbulence during transportation and suggest that the turbulent boundary layer shear flow is a good approximation to such pyroclastic density currents. We used the Coles formula to reconstruct velocity as a function of flow height during the formation of the finely laminated layer of Astroni and Agnano^Monte Spina base surges. The methodology we used allows the reconstruction of flow parameters just at a particular point in time and space of base-surge evolution,and does not provide the complete picture of the flow history of pyroclastic density currents. Nevertheless,flow velocity and density data, as obtained with the proposed approach,point to dynamic pressure values that are compatible with those reported for similar currents on other volcanoes. We conclude therefore that the results obtained give approximate but helpful information on the nature of such hazardous events at Campi Flegrei.
    Beschreibung: Published
    Beschreibung: 221-228
    Beschreibung: partially_open
    Schlagwort(e): base-surge deposits ; boundary layer ; pyroclastic density current ; phreatomagmatic eruptions ; 04. Solid Earth::04.04. Geology::04.04.08. Sediments: dating, processes, transport ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks
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    Materialart: article
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