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  • 04.06. Seismology  (17)
  • 01.02. Ionosphere  (5)
  • melt inclusions
  • MDPI  (9)
  • Oxford University Press  (8)
  • Elsevier  (6)
  • AGU  (1)
  • 2020-2022  (24)
  • 1990-1994
  • 1965-1969
  • 1
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    Retrospective short-term forecasting experiment in Italy based on the occurrence of strong (fore) shocks (2021)
    Oxford University Press
    Details
    Publikationsdatum: 2021-03-15
    Beschreibung: In a recent work we computed the relative frequencies with which strong shocks (4.0≤Mw〈5.0), widely felt by the population were followed in the same area by potentially destructive main shocks (Mw≥5.0) in Italy. Assuming the stationarity of the seismic release properties, such frequencies can be tentatively used to estimate the probabilities of potentially destructive shocks after the occurrence of future strong shocks. This allows us to set up an alarm-based forecasting hypothesis related to strong foreshocks occurrence. Such hypothesis is tested retrospectively on the data of a homogenized seismic catalogue of the Italian area against a purely random hypothesis that simply forecasts the target main shocks proportionally to the space-time fraction occupied by the alarms. We compute the latter fraction in two ways a) as the ratio between the average time covered by the alarms in each area and the total duration of the forecasting experiment (60 years) and b) as the same ratio but weighted by the past frequency of occurrence of earthquakes in each area. In both cases the overall retrospective performance of our forecasting algorithm is definitely better than the random case. Considering an alarm duration of three months, the algorithm retrospectively forecasts more than 70% of all shocks with Mw5.5 occurred in Italy from 1960 to 2019 with a total space-time fraction covered by the alarms of the order of 2%. Considering the same space-time coverage, the algorithm is also able to retrospectively forecasts more than 40% of the first main shocks with Mw5.5 of the seismic sequences occurred in the same time interval. Given the good reliability of our results, the forecasting algorithm is set and ready to be tested also prospectively, in parallel to other ongoing procedures operating on the Italian territory.
    Beschreibung: This paper benefitted from funding provided by the European Union within the ambit of the H2020 project RISE (No. 821115), which in particular fully financed the PhD grant of one of the authors (E.B.).
    Beschreibung: Published
    Beschreibung: 1192–1206
    Beschreibung: 6T. Studi di pericolosità sismica e da maremoto
    Beschreibung: JCR Journal
    Schlagwort(e): Earthquake interaction ; Statistical seismology ; forecasting, ; prediction ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 2
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    On the Source Parameters and Genesis of the 2017, Mw 4 Montesano Earthquake in the Outer Border of the Val d’Agri Oilfield (Italy) (2021)
    MDPI
    Details
    Publikationsdatum: 2021-03-24
    Beschreibung: On October 27, 2017, an Mw 4 earthquake occurred close to the municipality of Montesano sulla Marcellana, less than 10 km external to the concession of the largest European onshore hydrocarbon reservoir—the Val d’Agri oilfield (Southern Italy). Being a weak event located outside the extended monitoring domain of the industrial concession, the relevance of this earthquake and the possible links with the hydrocarbon exploitation were not extensively discussed. Actually, the analysis of shallow seismic events close to subsurface exploitation domains plays a significant role in the definition of key parameters in order to discriminate between natural, triggered, and induced seismicity, especially in tectonically active regions. The study of weak-to-moderate earthquakes can improve the characterization of the potentially destructive seismic hazard of this particular area, already struck by M 〉 6.5 episodes in the past. In this work, we analyze the source parameters of this Mw 4 earthquake by applying advanced seismological techniques to estimate the uncertainties derived from the moment tensor inversion and identify plausible directivity effects. The moment tensor is dominated by a NW–SE oriented normal faulting with a centroid depth of 14 km. A single ML 2.1 aftershock was recorded and used as the empirical Green’s function to calculate the apparent source time function for the mainshock. Apparent durations (in the range 0.11–0.21 s, obtained from S-waves) define an azimuthal pattern, which reveals an asymmetric bilateral rupture with 70% of the rupture propagation in the N310°Wdirection, suggesting a rupture plane dipping to the SW. Our results tally with the activation of a deeper fault segment associated with the Eastern Agri Fault System close to the basement as the origin of the Montesano earthquake. Finally, the Coulomb stress rate induced by depletion of the oilfield is calculated to quantify the trigger potential estimated for the Montesano earthquake yielding relatively low probabilities below 10%. Our analyses point toward the conclusion that the Mw 4 event was more likely due to the local natural tectonic stress, rather than induced or triggered by the long-term hydrocarbon extraction in the Val d’Agri oilfield.
    Beschreibung: Published
    Beschreibung: 617794
    Beschreibung: 3T. Fisica dei terremoti e Sorgente Sismica
    Beschreibung: JCR Journal
    Schlagwort(e): earthquake source ; induced seismicity ; directivity ; triggered earthquake ; Val d’Agri oilfield ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 3
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    Evaluation of Pre-Earthquake Anomalies of Borehole Strain Network by Using Receiver Operating Characteristic Curve (2021)
    MDPI
    Details
    Publikationsdatum: 2021-05-12
    Beschreibung: In order to monitor temporal and spatial crustal activities associated with earthquakes, ground- and satellite-based monitoring systems have been installed in China since the 1990s. In recent years, the correlation between monitoring strain anomalies and local major earthquakes has been verified. In this study, we further evaluate the possibility of strain anomalies containing earthquake precursors by using Receiver Operating Characteristic (ROC) prediction. First, strain network anomalies were extracted in the borehole strain data recorded in Western China during 2010–2017. Then, we proposed a new prediction strategy characterized by the number of network anomalies in an anomaly window, Nano, and the length of alarm window, Talm. We assumed that clusters of network anomalies indicate a probability increase of an impending earthquake, and consequently, the alarm window would be the duration during which a possible earthquake would occur. The Area Under the ROC Curve (AUC) between true predicted rate, tpr, and false alarm rate, fpr, is measured to evaluate the efficiency of the prediction strategies. We found that the optimal strategy of short-term forecasts was established by setting the number of anomalies greater than 7 within 14 days and the alarm window at one day. The results further show the prediction strategy performs significantly better when there are frequent enhanced network anomalies prior to the larger earthquakes surrounding the strain network region. The ROC detection indicates that strain data possibly contain the precursory information associated with major earthquakes and highlights the potential for short-term earthquake forecasting.
    Beschreibung: National Natural Science Foundation of China under Grant 41974084 Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan, under its observation and Research Program for Prediction of Earthquakes and Volcanic Eruptions.
    Beschreibung: Published
    Beschreibung: 515
    Beschreibung: 7T. Variazioni delle caratteristiche crostali e precursori sismici
    Beschreibung: JCR Journal
    Schlagwort(e): receiver operating characteristic ; a new prediction strategy ; frequent network anomalies ; prediction efficiency ; short-term earthquake forecasting ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 4
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    The Shallow Plumbing System of Piton de la Fournaise Volcano (La Reunion Island, Indian Ocean) Revealed by the Major 2007 Caldera-Forming Eruption (2021)
    Oxford University Press
    Details
    Publikationsdatum: 2021-02-10
    Beschreibung: The 2007 caldera-forming eruption of Piton de la Fournaise (PdF) erupted the largest volume of magma (210 Mm3)recorded at this volcano in at least three centuries. Major and trace element and Sr^Nd isotope data for bulk-rocks, groundmasses and olivine phenocrysts have been combined with melt inclusion data (major, trace and volatile elements) to track magma evolution over the whole eruptive sequence. We show that each eruptive phase had a distinctive geochemical and petrological signature and that caldera collapse on 5 April was preceded by a marked shift in bulk magma composition and crystal content and size. Aphyric basalt erupted at the beginning of the sequence (February 2007) had relatively high Sr isotope ratio (87Sr/86Sr ¼ 0·70420^0·704180) and low Nd isotopic ratio(143Nd/144Nd ¼ 0·51285^0·51286). Olivine-basalts extruded on2^5 April just before caldera collapse are less enriched in radiogenic Sr (87Sr/86Sr ¼ 0·70412^0·70416), but characterized by the same Nd isotopic composition. This magma is interpreted as a new deep input, which pressurized the shallow PdF plumbing system and triggered the 2007 activity. Post-collapse oceanite lavas represent the main volume of magma extruded in 2007. Their bulk-rocks and groundmasses have 87Sr/86Sr (0·70418) intermediate between those of February and 5 April, and similar to those of the March 2007 and 2001^2006 lavas.We show that the Steady State Basalts (SSB) commonly erupted at PdF are hybrid melts, which result from multistep mixing between ‘alkaline’and ‘transitional’end-members. Our results lead us to propose a new model of the PdF plumbing system to reconcile the petrological, geochemical and geophysical observations: (1) the shallow portion (above sea level) of the PdF plumbing system hosts several small sills, in which magma experiences variable degrees of degassing, cooling and crystallization; (2) oceanite lavas result from the withdrawal of shallow harrisitic mushes stored at low pressures (548 MPa; 51800^2400 m depth) below both the volcano summit and its eastern flank; (3) water degassing plays a major role in fast magma crystallization at shallow depths. Multistep ascent and periodic extrusion of the shallow magmas is promoted by injections of deeper and hotter basaltic magma, containing up to 1·3 wt % H2O and 1630 ppm S. In 2007, the new deep input was the ultimate source of the large excess in sulfur degassing detected by satellites. Lateral draining and intrusion of magma below the eastern flank of the volcano are the cause of major volcano deformation, flank sliding and summit caldera collapse.
    Beschreibung: Published
    Beschreibung: 1287-1315
    Beschreibung: 2V. Struttura e sistema di alimentazione dei vulcani
    Beschreibung: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Beschreibung: 4V. Processi pre-eruttivi
    Beschreibung: 6A. Geochimica per l'ambiente e geologia medica
    Beschreibung: JCR Journal
    Schlagwort(e): Piton de la Fournaise ; plumbing system ; magma reservoir ; caldera collapse ; melt inclusions ; volatile budget ; isotope geochemistry ; basalt
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 5
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    Seismic Coda-Waves Imaging Based on Sensitivity Kernels Calculated Using an Heuristic Approach (2021)
    MDPI
    Details
    Publikationsdatum: 2021-02-02
    Beschreibung: Abstract: In this paper we review and discuss the seismic method based on the analysis of seismic coda waves used in the last 10 years by the present authors and/or their co-workers, to produce separate images of intrinsic- and scattering attenuation in zones of peculiar geological interest (mainly volcanoes). Such separate attenuation images are considered by the scientific community as complementary to those from ordinary velocity-tomography and useful to improve the geological interpretation in volcanoes and in tectonically active zones. In this review we only list but do not discuss the most significative papers showing the images obtained, as we are focused to review the method and not the interpretation of data analysis. For sake of completeness, we anyway show also a new analysis applied to data from Stromboli volcano. We thus first introduce the physical model describing the seismogram Energy Envelope (derived from the solution of the Energy Transport integral Equation) and discuss its asymptotic approximations (Diffusion- and Single-scattering model). Then, we describe a numerical method to heuristically calculate the Sensitivity Kernels for the propagation of the scattered waves in the assumption of isotropic scattering. We attribute to these Sensitivity Kernels the physical meaning of probability that for a single source-receiver couple the measured attenuation parameters can be associated with the space coordinates. Based on this definition, the attenuation image can be obtained mapping the estimated attenuation parameters onto the zone under study weighting with the Sensitivity Kernels. We further discuss how to estimate the uncertainties associated with the results and report the list of the papers describing the (separated) scattering- and intrinsic-attenuation structures investigated using this approach.
    Beschreibung: Published
    Beschreibung: id304
    Beschreibung: 1T. Struttura della Terra
    Beschreibung: JCR Journal
    Schlagwort(e): seismic scattering ; seismic imaging ; sensitivity kernels ; seismic attenuation ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 6
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    An automatically generated high-resolution earthquake catalogue for the 2016–2017 Central Italy seismic sequence, including P and S phase arrival times (2021)
    Oxford University Press
    Details
    Publikationsdatum: 2021-03-24
    Beschreibung: The 2016–17 central Italy earthquake sequence began with the first mainshock near the town of Amatrice on August 24 (MW 6.0), and was followed by two subsequent large events near Visso on October 26 (MW 5.9) and Norcia on October 30 (MW 6.5), plus a cluster of 4 events with MW 〉 5.0 within few hours on January 18, 2017. The affected area had been monitored before the sequence started by the permanent Italian National Seismic Network (RSNC), and was enhanced during the sequence by temporary stations deployed by the National Institute of Geophysics and Volcanology and the British Geological Survey. By the middle of September, there was a dense network of 155 stations, with a mean separation in the epicentral area of 6–10 km, comparable to the most likely earthquake depth range in the region. This network configuration was kept stable for an entire year, producing 2.5 TB of continuous waveform recordings. Here we describe how this data was used to develop a large and comprehensive earthquake catalogue using the Complete Automatic Seismic Processor (CASP) procedure. This procedure detected more than 450,000 events in the year following the first mainshock, and determined their phase arrival times through an advanced picker engine (RSNI-Picker2), producing a set of about 7 million P- and 10 million S-wave arrival times. These were then used to locate the events using a non-linear location (NLL) algorithm, a 1D velocity model calibrated for the area, and station corrections and then to compute their local magnitudes (ML). The procedure was validated by comparison of the derived data for phase picks and earthquake parameters with a handpicked reference catalogue (hereinafter referred to as ‘RefCat’). The automated procedure takes less than 12 hours on an Intel Core-i7 workstation to analyse the primary waveform data and to detect and locate 3000 events on the most seismically active day of the sequence. This proves the concept that the CASP algorithm can provide effectively real-time data for input into daily operational earthquake forecasts, The results show that there have been significant improvements compared to RefCat obtained in the same period using manual phase picks. The number of detected and located events is higher (from 84,401 to 450,000), the magnitude of completeness is lower (from ML 1.4 to 0.6), and also the number of phase picks is greater with an average number of 72 picked arrival for a ML = 1.4 compared with 30 phases for RefCat using manual phase picking. These propagate into formal uncertainties of ± 0.9km in epicentral location and ± 1.5km in depth for the enhanced catalogue for the vast majority of the events. Together, these provide a significant improvement in the resolution of fine structures such as local planar structures and clusters, in particular the identification of shallow events occurring in parts of the crust previously thought to be inactive. The lower completeness magnitude provides a rich data set for development and testing of analysis techniques of seismic sequences evolution, including real-time, operational monitoring of b-value, time-dependent hazard evaluation and aftershock forecasting.
    Beschreibung: Published
    Beschreibung: 555–571
    Beschreibung: 3T. Fisica dei terremoti e Sorgente Sismica
    Beschreibung: JCR Journal
    Schlagwort(e): 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 7
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    Assessing Current Seismic Hazards in Irpinia Forty Years after the 1980 Earthquake: Merging Historical Seismicity and Satellite Data about Recent Ground Movements (2021)
    MDPI
    Details
    Publikationsdatum: 2021-04-13
    Beschreibung: Recently, a new strain rate map of Italy and the surrounding areas has been obtained by processing data acquired by the persistent scatterers (PS) of the synthetic aperture radar interferome- try (InSAR) satellites—ERS and ENVISAT—between 1990 and 2012. This map clearly shows that there is a link between the strain rate and all the shallow earthquakes (less than 15 km deep) that occurred from 1990 to today, with their epicenters being placed only in high strain rate areas (e.g., Emilia plain, NW Tuscany, Central Apennines). However, the map also presents various regions with high strain rates but in which no damaging earthquakes have occurred since 1990. One of these regions is the Apennine sector, formed by Sannio and Irpinia. This area represents one of the most important seismic districts with a well-known and recorded seismicity from Roman times up to the present day. In our study, we merged historical records with new satellite techniques that allow for the precise determination of ground movements, and then derived physical dimensions, such as strain rate. In this way, we verified that in Irpinia, the occurrence of new strong shocks—forty years after one of the strongest known seismic events in the district that occurred on the 23 November 1980, measuring Mw 6.8—is still a realistic possibility. The reason for this is that, from 1990, only areas characterized by high strain rates have hosted significant earthquakes. This picture has been also confirmed by analyzing the historical catalog of events with seismic completeness for magnitude M ≥ 6 over the last four centuries. It is easy to see that strong seismic events with magnitude M ≥ 6 generally occurred at a relatively short time distance between one another, with a period of 200 years without strong earthquakes between the years 1732 and 1930. This aspect must be considered as very important from various points of view, particularly for civil protection plans, as well as civil engineering and urban planning development.
    Beschreibung: Published
    Beschreibung: 168
    Beschreibung: 4T. Sismicità dell'Italia
    Beschreibung: JCR Journal
    Schlagwort(e): Irpinia ; seismic hazard ; strain rate ; GNSS ; InSAR ; earthquake ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 8
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    Erratum: On seismic ambient noise cross-correlation and surface-wave attenuation (2021)
    Oxford University Press
    Details
    Publikationsdatum: 2021-05-12
    Beschreibung: erratum paper
    Beschreibung: Published
    Beschreibung: 1090-1092
    Beschreibung: 1T. Struttura della Terra
    Beschreibung: JCR Journal
    Schlagwort(e): Theoretical seismology ; Seismic attenuation ; Seismic noise ; Surface waves ; Free oscillations ; Seismic interferometry ; 04.06. Seismology ; 04.01. Earth Interior
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 9
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    The Deep Plumbing System of Ischia: a Physico-chemical Window on the Fluid-saturated and CO2-sustained Neapolitan Volcanism (Southern Italy) (2021)
    Oxford University Press
    Details
    Publikationsdatum: 2021-05-12
    Beschreibung: Ischia, a volcanic island located 18 miles SW of Naples (Southern Italy), is a densely populated active caldera that last erupted in AD 1302. Melt inclusions in phenocrysts of the Vateliero and Cava Nocelle shoshonite^latite eruptive products (6th to 4th centuries BC) constrain the structure and nature of the Ischia deep magmatic feeding system.Their geochemical characteristics make Ischia a natural borehole for probing the physico-chemical conditions of magma generation in mantle contaminated by slab-derived fluids or melts, largely dominated by CO2.Volatile concentrations in olivine-hosted melt inclusions require gas^melt equilibria at between 3 and 18 km depth. In agreement with what has already been demonstrated at the other neighboring Neapolitan volcanoes (Procida, Campi Flegrei caldera and Somma^Vesuvius volcanic complex), a major crystallization depth at 8^10 km has been identified.The analyzed melt inclusions provide clear evidence for CO2-dominated gas fluxing and consequent dehydration of magma batches stagnating at crustal discontinuities. Gas fluxing is further supported by selective enrichment in K owing to fluid-transfer during magma differentiation.This takes place under oxidized conditions (Fe3þ /Fe 0·3) that can be fixed by an equimolar proportion of divalent and trivalent iron in the melt if post-entrapment crystallization of the host olivine is discarded.The melt inclusion data, together with data from the literature for other Neapolitan volcanoes, show that magmatism and volcanism in the Neapolitan area, despite differences in composition and eruption dynamics, are closely linked to supercritical CO2-rich fluids. These fluids are produced by devolatilization of subducting terrigenous^pelagic metasediments and infiltrate the overlying mantle wedge, generate magmas and control their ascent up to eruption. Geochemical characteristics of Ischia and the other Neapolitan volcanoes reveal that the extent of fluid or melt contamination of the pre-subduction asthenospheric mantle wedge was similar among these volcanoes. However, differences in the isotopic compositions of the erupted magmas (more enriched in radiogenic Sr at Ischia, Campi Flegrei and Somma^Vesuvius with respect to Procida) and the amount of H2O in the plumbing system of these volcanoes (almost double at Ischia, Campi Flegrei and Somma^Vesuvius than at Procida) reflect the different flow-rates of deep slab-derived fluids or melts through the mantle wedge, which, in turn, control the amount of generated magma.The high bulk permeability of the lithosphere below Ischia, Campi Flegrei and Somma^Vesuvius, determined by the occurrence of intersecting NW^SE and NE^SW regional fault systems, favours fluid ascent and accumulation at crustal levels, with consequent larger magma production and storage than at Procida, located along the NE^SW system.
    Beschreibung: Published
    Beschreibung: 951-984
    Beschreibung: 2V. Struttura e sistema di alimentazione dei vulcani
    Beschreibung: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Beschreibung: 4V. Processi pre-eruttivi
    Beschreibung: 6A. Geochimica per l'ambiente e geologia medica
    Beschreibung: JCR Journal
    Schlagwort(e): CO2-fluxing ; melt inclusions ; redox state ; trachybasalts
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 10
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    Sulphur behaviour and redox conditions in etnean magmas during magma differentiation and degassing (2021)
    Oxford University Press
    Details
    Publikationsdatum: 2021-06-21
    Beschreibung: Sulphur behaviour and variations in redox conditions during magma differentiation and degassing in the Mt Etna (Italy) volcanic system have been explored by integrating the study of olivine-hosted melt inclusions (MIs) with an experimental survey of sulphur solubility in hydrous basaltic magmas. Sulphur solubility experiments were performed at conditions relevant to the Etnean plumbing system (1200 C, 200MPa and oxygen fugacity between NNOþ0 2 and NNOþ1 7, with NNO being the nickel–nickel oxide buffer), and their results confirm the important control of oxygen fugacity (fO2) on S abundance in mafic magmas and on S partitioning between fluid and melt phases (DSfluid/melt). The observed DSfluid/melt value increases from 5164 to 14666 when fO2 decreases from NNOþ1 760 5 to NNOþ0 3. Based on the calculated DSfluid/melt and a careful selection of previously published data, an empirical model is proposed for basaltic magmas to predict the variation of DSfluid/melt values with variations in P (25–300 MPa), T (1030–1200 C) and fO2 (between NNO– 0 8 and NNOþ2 4). Olivine-hosted melt inclusions (Fo89-91) from tephra of the prehistoric (4 ka BP) sub-plinian picritic eruption, named FS (‘Fall Stratified’), have been investigated for their major element compositions, volatile contents and iron speciation (expressed as Fe3þ/PFe ratio). These primitive MIs present S content from 235677 to 34456168 ppm, and oxygen fugacity values, estimated from Fe3þ/PFe ratios, range from NNOþ0 760 2 to NNOþ1 660 2. Iron speciation has also been investigated in more evolved and volatile-poorer Etnean MIs. The only primitive melt inclusion from the Mt Spagnolo eruption (4–15 ka BP) presents a S content of 1515649ppm and an estimated fO2 of NNOþ1 460 1. The more evolved MIs (from 2002–2003, 2006, 2008–2009 and 2013 eruptions) have S content lower than 500 ppm, and their Fe3þ/RFe ratios result in fO2 between NNO– 0 960 1 and NNOþ0 460 1. Redox conditions and S behaviour in Etnean magmas during degassing and fractional crystallization were modelled coupling MELTS code with our empirical DSfluid/melt model. Starting from an FS-type magma composition and upon decrease of T and P, fractional crystallization of olivine, clinopyroxene, spinel and plagioclase causes a significant fO2 decrease. The fO2 reduction, in turn, causes a decrease in sulphur solubility and an increase in DSfluid/melt, promoting S exsolution during magma ascent, which further enhances the reduction of fO2. For the evolved MIs of 2002–2013 eruptions, magma differentiation may therefore have played a crucial role in decreasing redox conditions and favouring efficient S degassing. Differently, during the unusual FS eruption, only limited melt evolution is observed and S exsolution seems to have been triggered by a major pressure decrease accompanied by H2O and CO2 exsolution during fast magmatic ascent.
    Beschreibung: Published
    Beschreibung: egaa095
    Beschreibung: 4V. Processi pre-eruttivi
    Beschreibung: JCR Journal
    Schlagwort(e): melt inclusions ; sulphur solubility experiments ; XANES ; Mt. Etna ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 11
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    Scintillation modeling (2021)
    Elsevier
    Details
    Publikationsdatum: 2021-01-07
    Beschreibung: In this chapter, some scintillation models are described, taking into account of the dynamical nature of the Earth's ionosphere and its “complexity.” After a short description of the problem, a detailed explanation is provided about the propagation model named WAM, after its authors Wernik, Alfonsi, and Materassi. WAM is a propagation model based on a phase screen approach, where the statistical characteristics of the screen are constructed according to in situ data of ionospheric irregularities. Then, the Ground-Based Scintillation Climatology (GBSC) model is presented; this is a tool based on a wide statistical database from high performance receivers.
    Beschreibung: Published
    Beschreibung: 277-299
    Beschreibung: 2A. Fisica dell'alta atmosfera
    Schlagwort(e): 01.02. Ionosphere
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 12
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    Updated Antarctic crustal model (2021)
    Elsevier
    Details
    Publikationsdatum: 2021-01-05
    Beschreibung: We use seismic data together with a subglacial bedrock relief from the BEDMAP2 database to obtain a new three- layer model of the consolidated (crystalline) crust of Antarctica that locally improves the global seismic crustal model CRUST1.0. We collect suitable data for constructing crustal layers, analyse them and build maps of the crustal layer thickness and seismic velocities. We use the subglacial relief according to a tectonic configuration and then interpolate data using a statistical kriging method. The P-wave velocity information from old seismic profiles have been supplemented with the new shear-wave velocity models. We adjust the thickness of crustal layers by multiplying a total crustal thickness by a percentage ratio of each individual layer at each point. Our re- sults reveal large variations in seismic velocities between different crustal blocks forming Antarctica. The most pronounced differences exist between East and West Antarctica. In East Antarctica, a high P-wave velocity (vP 〉 7 km/s) layer in the lower crust is absent. The P-wave velocity in the lower crust changes from 6.1 km/s beneath the Lambert Rift to 6.9 km/s beneath the Wilkes Basin. In West Antarctica, a thick mafic lower crust is characterized by large P-wave velocities, ranging from 7.0 km/s under the Ross Sea to 7.3 km/s under the Byrd Basin. In contrast, velocities in the lower crust beneath the Transantarctic and Ellsworth-Whitmore Mountains are ~6.8 km/s. The P-wave velocities in the upper crust in East Antarctica are within the range 5.5–6.4 km/s. The upper crust of West Antarctica is characterized by the P-wave velocities of 5.6–6.3 km/s. The P-wave veloc- ities in the middle crust vary within 5.9–6.6 km/s in East Antarctica and within 6.3–6.5 km/s in West Antarctica. A low-velocity layer (5.8–5.9 km/s) is detected at depth of ~20–25 km beneath the Princes Elizabeth Land.
    Beschreibung: Published
    Beschreibung: 1-18
    Beschreibung: 1T. Struttura della Terra
    Beschreibung: JCR Journal
    Schlagwort(e): Crustal structure ; Sediments ; Antarctica ; Gondwana ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 13
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    Co-Seismic Magnetic Field Perturbations Detected by Swarm Three-Satellite Constellation (2021)
    MDPI
    Details
    Publikationsdatum: 2021-01-29
    Beschreibung: The first 5.3 years of magnetic data from three Swarm satellites have been systematically analyzed, and possible co-seismic magnetic disturbances in the ionosphere were investigated just a few minutes after the occurrence of large earthquakes. We preferred to limit the investigation to a subset of earthquakes selected in function of depth and magnitude. After a systematic inspection of the available data around (in time and space) the seismic events, we found 12 Swarm satellite tracks with co-seismic disturbances possibly produced by ten earthquakes from Mw5.6 to Mw6.9. The distance of the satellite to the earthquake epicenter corresponds to the measured distance-time arrival of the disturbance from the surface to the ionosphere, confirming that the identified disturbances are most likely produced by the seismic events. Secondly, we found a good agreement with a model that combined a propagation of the disturbance to the F2 ionospheric layer with an acoustic gravity wave at a velocity of about (2.2 0.3) km/s and a second faster phenomenon that transmits the disturbance from F2 layer to the Swarm satellite with a velocity of about (16 3) km/s as an electromagnetic scattering propagation.
    Beschreibung: Published
    Beschreibung: 1166
    Beschreibung: 7T. Variazioni delle caratteristiche crostali e precursori sismici
    Beschreibung: JCR Journal
    Schlagwort(e): coseismic phenomena ; ionospheric phenomena ; 01.02. Ionosphere ; 04.05. Geomagnetism ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 14
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    Ionospheric Turbulence and the Equatorial Plasma Density Irregularities: Scaling Features and RODI (2021)
    MDPI
    Details
    Publikationsdatum: 2021-03-10
    Beschreibung: In the framework of space weather, the understanding of the physical mechanisms responsible for the generation of ionospheric irregularities is particularly relevant for their effects on global positioning and communication systems. Ionospheric equatorial plasma bubbles are one of the possible irregularities. In this work, using data from the ESA Swarm mission, we investigate the scaling features of electron density fluctuations characterizing equatorial plasma bubbles. Results strongly support a turbulence character of these structures and suggest the existence of a clear link between the observed scaling properties and the value of the Rate Of change of electron Density Index (RODI). This link is discussed, and RODI is proposed as a reliable proxy for the identification of plasma bubbles.
    Beschreibung: This research received financial support from European Space Agency (ESA contract N. 4000125663/18/I-NB-“EO Science for Society Permanently Open Call for Proposals EOEP-5 BLOCK4” (INTENS)) and from the Italian MIUR-PRIN grant 2017APKP7T on “Circumterrestrial Environment: Impact of Sun–Earth Interaction”.
    Beschreibung: Published
    Beschreibung: 759
    Beschreibung: 2A. Fisica dell'alta atmosfera
    Beschreibung: JCR Journal
    Schlagwort(e): Turbulence ; Electron density irregularities ; Equatorial topside ionosphere ; Swarm constellation ; 01.02. Ionosphere
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 15
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    On the Heterogeneity of the Earthquake rupture (2021)
    Oxford University Press
    Details
    Publikationsdatum: 2021-04-14
    Beschreibung: The scaling of earthquake parameters with seismic moment and its interpretation in terms of self- similarity is still debated in the literature. We address this question by examining a worldwide compilation of corner frequency-based and elastic rebound theory (ERT)-based fault slip, area and stress drop values for earthquakes ranging in magnitude from -0.7 to 7.8. We find that corner frequency estimates of slip (and stress drop) scale differently than those inferred from the ERT approach, where the latter deviates from the generally accepted constant stress drop behavior of so- called self-similar scaling models. We also find that average slips from finite-source models are consistent with corner frequency scaling, whereas peak slip values are more consistent with the ERT scaling. The different scaling of corner frequency- and ERT-based estimates of slip and stress drop with earthquake size is interpreted in terms of heterogeneity of the rupture process. ERT-based estimates of stress drop decrease with seismic moment suggesting a self-affine behavior. Despite the inferred heterogeneity at all scales, we do not observe a clear effect on the Brune stress drop scaling with earthquake size.
    Beschreibung: Published
    Beschreibung: 1771–1781
    Beschreibung: 2T. Deformazione crostale attiva
    Beschreibung: JCR Journal
    Schlagwort(e): Earthquake dynamics ; Earthquake source observations ; Dynamics and mechanics of faulting ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 16
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    High-latitude polar pattern of ionospheric electron density: Scaling features and IMF dependence (2021)
    Elsevier
    Details
    Publikationsdatum: 2021-05-12
    Beschreibung: We investigated the average polar patterns of ionospheric electron density and the corresponding patterns of scaling features as a function of interplanetary magnetic field orientation. The focus is on the Northern Hemisphere using electron density data recorded on-board ESA Swarm A satellite. The first- and second-order scaling exponents have been evaluated by means of the -order structure functions. We used electron density measurements over a period of 15 months from April 1, 2014 to June 30, 2015, which corresponds to the maximum of solar cycle 24 and which is characterized by an average value of the solar radio flux (F10.7) index equal to (140+/- 30) sfu. Electron density, first- and second-order scaling exponents have been mapped and discussed for four main IMF orientations provided by Bx and By components under conditions of high solar activity. Large spatial changes of the second-order scaling exponent pattern are observed with a steepening of the associated spectral exponent in correspondence with the nightside polar cap trailing edge. Intermittency, defined as the departure from linearity of the dependence of scaling exponents on moment order q, is also evaluated finding that it is generally higher near the equatorward boundary of the auroral oval than elsewhere. On the whole, the found patterns of the electron density first- and second-order scaling exponents suggest the occurrence of turbulence at the high latitudes.
    Beschreibung: Published
    Beschreibung: 105531
    Beschreibung: 2A. Fisica dell'alta atmosfera
    Beschreibung: JCR Journal
    Schlagwort(e): Polar ionosphere ; Turbulence ; Scaling feature ; Space weather ; Swarm satellite ; electron density ; 01.02. Ionosphere ; 01.03. Magnetosphere
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 17
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    Crustal and uppermost mantle shear wave velocity structure beneath the Middle East from surface wave tomography (2021)
    Oxford University Press
    Details
    Publikationsdatum: 2021-05-12
    Beschreibung: We have constructed a 3-D shear wave velocity (Vs) model for the crust and uppermost mantle beneath the Middle East using Rayleigh wave records obtained from ambient-noise cross-correlations and regional earthquakes. We combined one decade of data collected from 852 permanent and temporary broad-band stations in the region to calculate group-velocity dispersion curves. A compilation of 〉54 000 ray paths provides reliable group-velocity measurements for periods between 2 and 150 s. Path-averaged group velocities calculated at different periods were inverted for 2-D group-velocity maps. To overcome the problem of heterogeneous ray coverage, we used an adaptive grid parametrization for the group-velocity tomographic inversion. We then sample the period-dependent group-velocity field at each cell of a predefined grid to generate 1-D group-velocity dispersion curves, which are subsequently inverted for 1-D Vs models beneath each cell and combined to approximate the 3-D Vs structure of the area. The Vs model shows low velocities at shallow depths (5–10 km) beneath the Mesopotamian foredeep, South Caspian Basin, eastern Mediterranean and the Black Sea, in coincidence with deep sedimentary basins. Shallow high-velocity anomalies are observed in regions such as the Arabian Shield, Anatolian Plateau and Central Iran, which are dominated by widespread magmatic exposures. In the 10–20 km depth range, we find evidence for a band of high velocities (〉4.0 km s–1) along the southern Red Sea and Arabian Shield, indicating the presence of upper mantle rocks. Our 3-D velocity model exhibits high velocities in the depth range of 30–50 km beneath western Arabia, eastern Mediterranean, Central Iranian Block, South Caspian Basin and the Black Sea, possibly indicating a relatively thin crust. In contrast, the Zagros mountain range, the Sanandaj-Sirjan metamorphic zone in western central Iran, the easternmost Anatolian plateau and Lesser Caucasus are characterized by low velocities at these depths. Some of these anomalies may be related to thick crustal roots that support the high topography of these regions. In the upper mantle depth range, high-velocity anomalies are obtained beneath the Arabian Platform, southern Zagros, Persian Gulf and the eastern Mediterranean, in contrast to low velocities beneath the Red Sea, Arabian Shield, Afar depression, eastern Turkey and Lut Block in eastern Iran. Our Vs model may be used as a new reference crustal model for the Middle East in a broad range of future studies.
    Beschreibung: Published
    Beschreibung: 1349-1365
    Beschreibung: 1T. Struttura della Terra
    Beschreibung: JCR Journal
    Schlagwort(e): 04.01. Earth Interior ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 18
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    Near-source simulation of strong ground motion in Amatrice downtown including site effects (2021)
    MDPI
    Details
    Publikationsdatum: 2021-04-30
    Beschreibung: On 24 August 2016, a Mw 6.0 earthquake started a damaging seismic sequence in central Italy. The historical center of Amatrice village reached the XI degree (MCS scale) but the high vulnerability alone could not explain the heavy damage. Unfortunately, at the time of the earthquake only AMT station, 200 m away from the downtown, recorded the mainshock, whereas tens on temporary stations were installed afterwards. We propose a method to simulate the ground motion affecting Amatrice, using the FFT amplitude recorded at AMT, which has been modified by the standard spectral ratio (SSR) computed at 14 seismic stations in downtown. We tested the procedure by comparing simulations and recordings of two later mainshocks (Mw 5.9 and Mw 6.5), underlining advantages and limits of the technique. The strong motion variability of simulations was related to the proximity of the seismic source, accounted for by the ground motion at AMT, and to the peculiar site effects, described by the transfer function at the sites. The largest amplification characterized the stations close to the NE hill edge and produced simulated values of intensity measures clearly above one standard deviation of the GMM expected for Italy, up to 1.6 g for PGA.
    Beschreibung: The grant of A.T. is funded by INGV and Department of Sciences, Roma Tre University (MIUR-Italy Dipartimenti di Eccellenza, Art.1, Commi 314-337 Legge 232/2016).
    Beschreibung: Published
    Beschreibung: 186
    Beschreibung: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Beschreibung: JCR Journal
    Schlagwort(e): strong ground motion ; earthquake simulation ; near-source ; Amatrice earthquake ; seismic sequence ; site effects ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 19
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    Electric Field Multifractal Features in the High-Latitude Ionosphere: CSES-01 Observations (2021)
    MDPI
    Details
    Publikationsdatum: 2021-05-31
    Beschreibung: In the polar ionosphere, the electric field is characterized by broadband and power law spectral densities at small/short spatio-temporal scales, which support a possible turbulent nature of the electric field fluctuations. Here, we investigate the multifractal character of the full three-dimensional electric field in the polar ionosphere as recorded on board the first Chinese Seismo- Electromagnetic Satellite (CSES-01). The results of our analysis prove a clear different degree of multifractality of the electric field fluctuations approaching either the polar cap trailing edge or the auroral region. The observed differences in the multifractal character are interpreted in terms of the different natures of the particle precipitation in the polar cap and in the auroral region. A possible link between the multifractal nature of electric field fluctuations, parallel to the geomagnetic field, and filamentation of field aligned currents (FACs) is established
    Beschreibung: Contract ASI “LIMADOU Scienza+” n 2020-31-HH.0 PNRA18 00289-A “Space weather in Polar Ionosphere: the Role of Turbulence”.
    Beschreibung: Published
    Beschreibung: 646
    Beschreibung: 2A. Fisica dell'alta atmosfera
    Beschreibung: JCR Journal
    Schlagwort(e): auroral ionosphere ; electric field ; Turbulence ; Fractals ; 01.02. Ionosphere
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 20
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    Modeling of earthquake chronology from paleoseismic data: Insights for regional earthquake recurrence and earthquake storms in the Central Apennines (2021)
    Elsevier
    Details
    Publikationsdatum: 2021-09-13
    Beschreibung: Among the geologic data, trenching records of paleoearthquakes represent an important input for the development of seismic hazard evaluations and, specifically, for the characterization of fault rupture behavior in time. Based on the available paleoseismological trenching data in the Central Apennines we have compiled a new database of surface faulting earthquakes for 10 faults. The compilation contains 109 surface faulting events, occurred in the past ~28 kyr. Events younger than 7 kyr (59 dated events) are much better constrained and, therefore, are the basis for most of the analyses. Through a quantitative multistep method, we integrate paleoseismic trench data and treat them statistically, providing relevant improvement needed for trenching-based seismic hazard evaluation. Indeed, the combined analysis of trenching data from multiple sites on the same fault led to a reduction of the approximations and uncertainties in the rupture history of individual faults. The procedure was also applied on specific fault systems and indicated that the single faults may have occasionally ruptured simultaneously, or close in time, in the past. The whole set of age ranges was also statistically analyzed to produce regional earthquake scenarios for a period much longer than the millennial historical record. The built scenarios for the last 7 kyr define a regional mean inter event time (IET) of 230-240 yr, comparable with the average recurrence time of about 200 yr, considering the number of events in time. We also identify the possible occurrence of earthquake storms, i.e., concentration of surface faulting earthquakes in the region within time periods of 200 yr, suggesting a variability in time of the seismic behavior of the faults, with alternation of peaks of activity with more “quiet” periods. Even though the paleoseismic data from the Apennines contains uncertainties, the results appear quite stable and promising for future applications in earthquake-hazard assessment.
    Beschreibung: Published
    Beschreibung: 229016
    Beschreibung: 6T. Studi di pericolosità sismica e da maremoto
    Beschreibung: JCR Journal
    Schlagwort(e): Paleoseismology ; Statistical modeling ; Surface rupture scenarios ; Regional earthquake recurrence ; Earthquake storms ; Central Apennines ; 04.04. Geology ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 21
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    Seismic Ambient Noise Imaging of a Quasi-Amagmatic Ultra-Slow Spreading Ridge (2021)
    MDPI
    Details
    Publikationsdatum: 2021-09-21
    Beschreibung: Passive seismic interferometry has become very popular in recent years in explorationgeophysics. However, it has not been widely applied in marine exploration. The purpose of thisstudy is to investigate the internal structure of a quasi-amagmatic portion of the Southwest IndianRidge by interferometry and to examine the performance and reliability of interferometry in marineexplorations. To reach this goal, continuous vertical component recordings from 43 ocean bottomseismometers were analyzed. The recorded signals from 200 station pairs were cross-correlated inthe frequency domain. The Bessel function method was applied to extract phase–velocity dispersioncurves from the zero crossings of the cross-correlations. An average of all the dispersion curveswas estimated in a period band 1–10 s and inverted through a conditional neighborhood algorithmwhich led to the final 1D S-wave velocity model of the crust and upper mantle. The obtained S-wavevelocity model is in good agreement with previous geological and geophysical studies in the regionand also in similar areas. We find an average crustal thickness of 7 km with a shallow layer of lowshear velocities and high Vp/Vs ratio. We infer that the uppermost 2 km are highly porous and maybe strongly serpentinized.
    Beschreibung: Published
    Beschreibung: 2811
    Beschreibung: 1T. Struttura della Terra
    Beschreibung: JCR Journal
    Schlagwort(e): 04.06. Seismology ; 04.01. Earth Interior
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 22
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    Tectonics and seismicity in the Northern Apennines driven by slab retreat and lithospheric delamination (2020)
    Elsevier
    Details
    Publikationsdatum: 2020-06-10
    Beschreibung: Understanding how long-term subduction dynamics relates to the short-term seismicity and crustal tec tonics is a challenging but crucial topic in seismotectonics. We attempt to address this issue by linking long-term geodynamic evolution with short-term seismogenic deformation in the Northern Apennines. This retreating subduction orogen displays tectonic and seismogenic behaviors on various spatiotemporal scales that also characterize other subduction zones in the Mediterranean area. We use visco-elasto-plastic seismo-thermo-mechanical (STM) modeling with a realistic 2D setup based on available geological and geophysical data. The subduction dynamics and seismicity are coupled in the numerical modeling, and driven only by buoyancy forces, i.e., slab pull. Our results suggest that lower crustal rheology and lithospheric mantle temperature modulate the crustal tectonics of the Northern Apennines, as inferred by previous studies. The observed spatial distribution of upper crustal tectonic regimes and surface displacements requires buoyant, highly ductile material in the subduction channel beneath the internal part of the orogen. This allows protrusion of the asthenosphere in the lower crust and lithospheric delamination associated with slab retreat. The resulting surface velocities and principal stress axes generally agree with present-day observations, suggesting that slab delamination and retreat can explain the dynamics of the orogen. Our simulations successfully reproduce the type and overall distribution of seismicity with thrust faulting events in the external part of the orogen and normal faulting in its internal part. Slab temperatures and lithospheric mantle stiffness affect the cumulative seismic moment release and spatial distribution of upper crustal earthquakes. The properties of deep, sub-crustal material are thus shown to influence upper crustal seismicity in an orogen driven by slab retreat, even though the upper crust is largely decoupled from the lithospheric mantle. Our simulations therefore highlight the effect of deep lower crustal rheologies, self-driven subduction dynamics and mantle properties in controlling shallow deformation and seismicity.
    Beschreibung: Published
    Beschreibung: 228481
    Beschreibung: 1T. Struttura della Terra
    Beschreibung: 2T. Deformazione crostale attiva
    Beschreibung: JCR Journal
    Schlagwort(e): Numerical modeling ; Geodynamics ; Seismotectonics orogen ; Delamination ; Northern Apennines ; 04.06. Seismology ; 04.03. Geodesy ; 05.01. Computational geophysics ; 04.07. Tectonophysics
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 23
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    Anomalous seismo-LAI variations potentially associated with the 2017 Mw = 7.3 Sarpol-e Zahab (Iran) earthquake from Swarm satellites, GPS-TEC and climatological data (2020)
    Elsevier
    Details
    Publikationsdatum: 2020-03-03
    Beschreibung: The Mw = 7.3 earthquake near the Iran-Iraq border in west Iran (34.911°N, 45.959°E) occurred at 18:18:17 UTC (LT = UTC + 03:30), November 12, 2017 as the result of oblique-thrust faulting at mid-crustal depth (∼19 km). Median, Kalman filter and Neural Network, as three standard, classical and intelligent methods, have been implemented to investigate three months of GPS Total Electron Content (TEC) measurements and to detect the striking anomalous variations around the time and location of the mentioned earthquake. The first method detects unusual variations, 9 days before the event, between 21:00 and 22:00 UTC. The other two methods of Kalman filter and Neural Network detect another clear anomaly on 11 days preceding the earthquake at 16:00 UTC. These findings are two of the outstanding results of GPS-TEC precursor analysis. This paper also presents the results of Swarm satellites (Alpha, Bravo and Charlie) data analysis inside the Dobrovolsky area around the Iran earthquake epicenter during the period from 1 August to 30 November 2017. The time series and orbital analysis of six measured parameters including electron density, electron temperature, magnetic scalar and vectors (X, Y, Z) components indicate irregular variations between 8 and 11 days prior to the occurrence of the earthquake. Since the variations of the solar and geomagnetic indices follow a normal behaviour during the whole period of the observed ionospheric anomalies between 8 and 11 days before the earthquake, it can be concluded that multi-precursors analysis has an important role to acknowledge the seismo-LAI (Lithospheric-Atmospheric-Ionospheric) anomalies associated to strong earthquakes such as this case. Furthermore, some physical and chemical atmospheric parameters from a climatological database are investigated and some interesting anomalies above two standard deviations prior to the earthquake are found. This paper shows not only anomalies in atmosphere and ionosphere but also a contemporary analysis of different data sources to detect the possible Lithosphere Atmosphere Ionosphere Coupling (LAIC) effects.
    Beschreibung: ASI
    Beschreibung: Published
    Beschreibung: 143-158
    Beschreibung: 7T. Variazioni delle caratteristiche crostali e precursori sismici
    Beschreibung: JCR Journal
    Schlagwort(e): Earthquake precursors ; LAIC ; 04.06. Seismology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 24
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    Can Building Seismic Resiliency Benefit from Emergent Technologies? Case Studies from the Projects KnowRISK and 3DTeLC (2020)
    AGU
    Details
    Publikationsdatum: 2020-01-20
    Beschreibung: Building resiliency to natural hazards like earthquakes requires worldwide engagement, starting from education and dissemination of good practice among the youths. Education of new professionals in the field of seismic risk takes nowadays advantage from the implementation of emergent technologies, such as Augmented Reality (AR) and Virtual Reality (VR), which can benefit from the huge amount of digital information available. We present a few case studies from two European projects promoting education and communication also throughout the application of AR and VR. Targeted audiences of the two projects were schools and universities. KnowRISK (Know your city, Reduce seISmic risK through non-structural elements; Grant agreement ECHO/SUB/2015/718655/PREV28) ended in 2018; it had a special focus on non-structural damage caused by earthquakes, exploring the causes of disruption and proposing preventive measures to reduce it. 3DTeLC is funded through the Erasmus+ Key Action 2 Strategic Partnerships for Higher Education scheme (Project Reference: 2017-1-UK01-KA203-036719) and will be completed in 2020. The project trains students to navigate 3D models of volcanic regions in Iceland, Greece, and Italy (at Mt. Etna volcano), allowing them to carry out virtual surveys also in hazardous contexts. Accordingly, the project aims at strengthening students’ skills in Earth observation and data analysis.
    Beschreibung: Published
    Beschreibung: San Francisco, CA, USA
    Beschreibung: 2TM. Divulgazione Scientifica
    Schlagwort(e): seismic resiliency ; natural hazards ; education ; communication ; augmented reality ; virtual reality ; 04.06. Seismology ; 05.03. Educational, History of Science, Public Issues ; 05.08. Risk
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: Poster session
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