ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Elsevier  (289)
  • MDPI  (211)
  • American Meteorological Society  (124)
  • MDPI Publishing
  • Springer Science+Business Media B.V. (formerly Kluwer Academic Publishers)
  • 2020-2023  (624)
Collection
Years
Year
  • 1
    Publication Date: 2022-04-01
    Description: Volcanic hazard assessment relies on the accurate knowledge of the eruptive style and recurrence of volcanic eruptions in the past. At El Hierro (Canary Islands) historical and prehistorical records are still poorly defined, and although the island was the location of one of the most recent eruptions (La Restinga, 2011 CE) of the Canarian archipelago, the recent subaerial volcanism is still poorly studied. Information about the age of Holocene volcanic activity as well as the stratigraphy of the deposits is scarce: few eruptions are dated so far, whereas the others are classified as pre-or Holocene events considering lava flow characteristics along the coast. Here, we report on the dating of eleven (M˜na Chamuscada, M˜na del Tesoro, Orchilla, Las Calcosas, M˜na Negra, Lomo Negro, Below Lomo Negro, Cuchillo del Roque, Malpaso Member, and M˜na del Guanche) Holocene subaerial eruptions, distributed along the three rift zones, combining paleomagnetic and 14C methods. We also provide geochemical analyses for nine of them. Results indicate that M˜na Chamuscada and M˜na del Tesoro occurred more recently than previously considered, setting them within the last two thousand years. Conversely, paleomagnetic and 14C ages found for Lomo Negro eruption are consistent with literature data (Villasante- Marcos and Pav´on-Carrasco, 2014) and constrain the occurrence of this event in the XVI century CE. Finally, for Malpaso Member deposits, the two 14C datings obtained by charcoals found below and above the trachytic layer set the eruption during the Holocene epoch, between ~7300 BCE and ~4700 BCE. For the other eruptions, in two cases (Orchilla and Las Calcosas) many possible time windows during the last 14 ka have been found, whereas a few possible ages have been obtained for the others. On the whole, the resulting chronological reconstruction of the recent activity of El Hierro indicates that eruptions occurred unevenly along the three main rifts, with nine eruptions in the WNW rift, six in the NE rift, and four in the SSE rift. We document at least two periods characterized by high eruptive frequency: an old one, between 8000 BCE and 1000 BCE, with eight eruptions, three of which characterized by more evolved compositions (phonotephrite and trachyte), and a recent one, between 1000 BCE and present day, with at least seven eruptions, mainly showing basanite compositions. The new data yield a significant improvement of Holocene eruption chronology, thus are instrumental for a correct evaluation of the volcanic hazard at El Hierro.
    Description: Published
    Description: 107526
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: JCR Journal
    Keywords: Paleomagnetism ; El Hierro ; 04.05. Geomagnetism ; 04.08. Volcanology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2022-04-01
    Description: The Gutenberg–Richter law and the Omori law are both characterized by a scaling behavior. However, their relation is still an open question. Although several hypotheses have been formulated, a comprehen- sive geophysical mechanism is still missing to explain the observed variability of the scaling exponents b-value and p-value, e.g., correlating the seismic cycle to statistical seismology and tectonic processes. In this work, a model for describing the size-frequency scaling and the temporal evolution of seismicity is proposed starting from simple assumptions. The parameter describing how the number of earthquakes decreases after a major seismic event, p, turns out to be positively correlated to the exponent of the frequency-size distribution of seismicity, b, and related to tectonics. Our findings suggest that p ≈ 23 (b + 1). It implies that a relationship between fracturing regimes, “efficiency” of the seismic process, duration of the seismic sequences and geodynamic setting exists, with outstanding potential impact on seismic hazard. On the other hand, the Gutenberg–Richter law simply reflects the tendency of the segments of the Earth’s crust to reach mechanical stability via constrained energy-budget optimization. Each perturbation has a probability of growing an earthquake or not, depending on disorder within the fault zone and the energy accumulated in the adjoining volume, mainly controlling the evolution of seismic sequences. The results are consistent with the different energy sources related to the tectonic settings, i.e., gravitational in extensional regimes, having higher b and p values, and generating lower maximum magnitude earthquakes with respect to strike-slip and contractional settings, which are rather fueled by elastic energy, showing lower b and p values, and they may generate higher magnitude events.
    Description: Published
    Description: 117511
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: JCR Journal
    Keywords: Gutenberg–Richter distribution ; fracturing and fault disorder ; Omori–Utsu law ; earthquake triggering ; tectonic setting ; 04.06. Seismology ; 04.07. Tectonophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2022-04-11
    Description: Natural sites in urban spaces can have a key role in citizen well-being, providing fundamental ecosystem services to the population and assuring a multitude of benefits. Therefore, cities should guarantee a number of green areas and their conservation in time as an essential part of urban architecture. In this framework, cooperation between scientists, decision makers and citizens is critical to ensure the enhancement of green public spaces. Social and scientific communities are called to work in a tuned way to combine scientific knowledge and methods to local socio-economic contexts, driven by the values of geoethics. The Bullicante Lake case study, discussed in this work, represents an example of application of geoethical values, such as inclusiveness, sharing, sustainability and conservation of bio- and geodiversity. This urban lake in Rome appeared following illegal excavation works in 1992 and remained closed until 2016 favouring re-naturalization processes. Over time, this site was often threatened by pending actions for building. The aim of this study was to highlight how fruitful cooperation between science and citizens is able to transform a degraded urban area into a place of knowledge, recreation, enjoyment and eco-systemic preservation. Moreover, on the basis of this experience, the authors proposed a generalised approach/strategy to be developed and applied in other contexts. The active involvement of citizens and the cooperation among scientists, artists and institutions were able to redress opportunistic behaviours well by preventing site degradation and its improper use, favouring environmental safeguarding and making possible the site’s recognition as a natural monument. The results of these actions led to the improved quality of citizen life, showing an excellent example of virtuous cooperation between science and society.
    Description: Published
    Description: 4429
    Description: 1TM. Formazione
    Description: 2TM. Divulgazione Scientifica
    Description: JCR Journal
    Keywords: geoethics ; conservation ; education ; citizen participation ; ecosystems ; urban lake ; green areas ; Rome ; 05.09. Miscellaneous ; 05.03. Educational, History of Science, Public Issues
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2022-04-04
    Description: The Adventure Plateau, located in the NW sector of the Sicilian Channel, experienced several episodes of exposure/erosion and subsequent drowning, with the most recent occurring after the Last Glacial Maximum (LGM). Unlike other parts of the Sicilian Channel, the Adventure Plateau is relatively tectonically stable and is therefore best suitable for reconstructing its coastal configuration before the post-LGM marine transgression. Here, we use high-resolution seismic data to identify and map the palaeo-coastline at the LGM on the basis of the internal architecture of the prograding wedges (i.e., the location of the subaqueous clinoform rollover point) and the erosional markers such as the subaerial unconformities and the wave ravinement surfaces. These data, which show an extreme variability in the palaeo-morphology of the coastal margins of the Adventure Plateau, have been complemented with vintage seismic profiles in order to entirely cover its perimeter. The mapped LGM coastline has then been compared to predictions from glacial isostatic adjustment (GIA) modeling, which considers the horizontal migration of the shorelines in response to sea level rise and to Earth’s rotational and deformational effects associated with deglaciation. The two shorelines (i.e., the coastline derived from the marine data interpretation and the one derived from the GIA model) are in good agreement at 21 kyears BP, although some discrepancies occur in the southern part of the plateau, where the seabed slope is extremely gentle, which makes the clinoform rollover points and the buried erosional unconformities difficult to detect. After 20 kyears BP, an acceleration in the rate of the sea level rise occurred. The results of this study indicate the importance of comparing experimental data with model predictions in order to refine and calibrate boundary parameters and to gain a better picture of the evolution of sea level rise over various time scales. View Full-Text
    Description: Published
    Description: 125
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2022-03-31
    Description: The pressure-gradient current is among the weaker ionospheric current systems arising from plasma pressure variations. It is also called diamagnetic current because it produces a magnetic field which is oriented oppositely to the ambient magnetic field, causing its reduction. The magnetic reduction can be revealed in measurements made by low-Earth orbiting satellites flying close to ionospheric plasma regions where rapid changes in density occur. Using geomagnetic field, plasma density and electron temperature measurements recorded on board ESA Swarm A satellite from April 2014 to March 2018, we reconstruct the flow patterns of the pressure-gradient current at high-latitude ionosphere in both hemispheres, and investigate their dependence on magnetic local time, geomagnetic activity, season and solar forcing drivers. Although being small in amplitude these currents appear to be a ubiquitous phenomenon at ionospheric high latitudes characterized by well defined flow patterns, which can cause artifacts in the main field models. Our findings can be used to correct magnetic field measurements for diamagnetic current effect, to improve modern magnetic field models, as well as to understand the impact of ionospheric irregularities on ionospheric dynamics at small-scale sizes of a few tens of kilometers.
    Description: Published
    Description: 1428
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: JCR Journal
    Keywords: High-latitude ionosphere ; Pressure-gradient current ; Diamagnetic current ; Swarm constellation ; 01.02. Ionosphere ; 04.05. Geomagnetism
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2022-04-13
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2022-03-02
    Description: The continental margin of the Ross Sea has been consistently sensitive to the advance and retreat of the Ross Ice Sheet (RIS) between the interglacial and glacial periods. This study examines changes of the glaciomarine sedimentation on the continental slope and rise to the eastern side of Hillary Canyon in the central Ross Sea, using three gravity cores collected at increasing water depths. Besides older AMS 14C ages of bulk sediments, based on the analytical results, sediment lithology was divided into units A, B1, and B2, representing Holocene, deglacial, and glacial periods, respectively. The sedimentation rate decreased as the water depth increased, with a higher sedimentation rate in the deglacial period (unit B1) than the Holocene (unit A). Biological productivity proxies were significantly higher in glacial unit B2 than in interglacial unit A, with transitional values observed in deglacial unit B1. Biological productivity generally decreased in the Antarctic continental margin during the glacial period because of extensive sea ice coverage. The higher biogenic contents in unit B2 are primarily attributed to the increased transport of eroded and reworked shelf sediments that contained abundant biogenic components to the continental slope and rise beneath the advancing RIS. Thus, glacial sedimentation on the continental slope and rise of the central Ross Sea was generally governed by the activity of the RIS, which generated melt-water plumes and debris flows at the front of the grounding line, although the continental rise might have experienced seasonally open conditions and lateral effects due to the bottom current.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    facet.materialart.
    Unknown
    Elsevier
    In:  EPIC3Science for the Protection of Indonesian Coastal Ecosystems (SPICE), Science for the Protection of Indonesian Coastal Ecosystems (SPICE), Amsterdam, Netherlands, Elsevier, 457 p., pp. 143-199, ISBN: 978-0-12-815050-4
    Publication Date: 2022-03-04
    Description: Abstract Ecological and social processes of the Spermonde Archipelago, South Sulawesi, Indonesia, have been intensively studied during the Science for the Protection of Indonesian Coastal Ecosystems (SPICE) program. The archipelago is of specific interest to better understand how intensive exploitation of marine resources results in the degradation of reef systems. The projects specifically targeted (1) ecological processes in coral reefs, (2) genetic structure of populations, and (3) social–ecological dynamics relating to resource use, social networks, and governance structures. A modeling component emphasized (4) the integration of different ecological, social, and environmental components. Results indicated that reef resources in the Spermonde Archipelago are intensively exploited and further stressed by pollution effluents from hinterland processes. The lack of alternative livelihoods perpetuates dependencies within the patron–client system of the artisanal fisheries and supports high exploitation and also destructive resource uses. Greater inclusion of local stakeholders in the governance may result in better conservation practices, sustainable resource use, and improved livelihoods for the people. Abstrak Selama proyek SPICE, aspek ekologis dan sosial di perairan Kepulauan Spermonde, Sulawesi Selatan, Indonesia, dipelajari secara intensif. Kepulauan dan perairan ini mengundang banyak perhatian untuk lebih memahami bagaimana tingkat pemanfaatan sumber daya laut yang intensif berakibat pada degradasi sistem terumbu karang. Kerangka kerja proyek penelitian SPICE, secara khusus, menargetkan kajian-kajian mengenai (a) proses ekologis dalam sistem terumbu karang, (b) struktur genetik populasi untuk menentukan konektifitasnya, dan (c) dinamika sosial-ekologi yang berkaitan dengan penggunaan sumber daya, jejaring sosial dan struktur tata kelola. Komponen pemodelan juga dimasukkan kedalam kajian mengenai (d) integrasi berbagai komponen ekologi, sosial dan lingkungan dalam karakterisasi sistem sosial-ekologis. Hasil-hasil penelitian menunjukkan bahwa sumber daya terumbu karang di Kepulauan Spermonde sangat tereksploitasi dan terancam juga oleh limbah polusi dari proses di daratan. Kurangnya mata pencaharian alternatif memperkuat ketergantungan para nelayan tradisional pada sistem patron-klien dan meningkatkan penggunaan sumber daya yang tidak berkelanjutan dan merusak. Keikutsertaan pemangku kepentingan lokal yang lebih erat dalam tata kelola sumber daya alam Kepulauan Spermonde sangat memungkinkan hasil praktik konservasi yang lebih baik, penggunaan sumber daya berkelanjutan, dan peningkatan mata pencaharian bagi masyarakat.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2022-03-03
    Description: The Monte San Nicola area (Southern Sicily) offers a spectacular exposure of open-marine sediments that were employed in 1998 for defining the Global Stratotype Section and Point (GSSP) of the Gelasian Stage (Upper Pliocene). After the lowering of the Pliocene/Pleistocene boundary to ca. 2.6 Ma in 2010, the Gelasian GSSP has been redefined as the base of both the Pleistocene Series and the Quaternary Period, which increased its importance and visibility within the scientific community. However, documentation on the Monte San Nicola reference section is still sparse. In the light of its renewed status, we decided to undertake a complete revision of the Gelasian Stage in its type area, in order to evaluate whether the succession of bio- and magnetostratigraphic events that are expected to occur in the interval of relevance are represented adequately in the local record. The results of our investigation demonstrate that the Monte San Nicola succession spans continuously from the upper Piacenzian to the lower Calabrian, and is therefore suitable to host the Unit Stratotype, or even the Astronomical Unit Stratotype, of the Gelasian Stage.
    Description: Published
    Description: 107367
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2022-03-07
    Description: The investigation of the role played by CO2 circulating within the mantle during partial melting and metasomatic/refertilization processes, together with a re-consideration of its storage capability and re-cycling in the lithospheric mantle, is crucial to unravel the Earth's main geodynamic processes. In this study, the combination of petrology, CO2 content trapped in bulk rock- and mineral-hosted fluid inclusions (FI), and 3D textural and volumetric characterization of intra- and inter-granular microstructures was used to investigate the extent and modality of CO2 storage in depleted and fertile (or refertilized) Sub-Continental Lithospheric Mantle (SCLM) beneath northern Victoria Land (NVL, Antarctica). Prior to xenoliths entrainment by the host basalt, the Antarctic SCLM may have stored 0.2 vol% melt and 1.1 vol% fluids, mostly as FI trails inside mineral phases but also as inter-granular fluids. The amount of CO2 stored in FI varies from 0.1 μg(CO2)/g(sample) in olivine from the anhydrous mantle xenoliths at Greene Point and Handler Ridge, up to 187.3 μg/g in orthopyroxene from the highly metasomatized amphibole-bearing lherzolites at Baker Rocks, while the corresponding bulk CO2 contents range from 0.3 to 57.2 μg/g. Irrespective of the lithology, CO2 partitioning is favoured in orthopyroxene and clinopyroxene-hosted FI (olivine: orthopyroxene = 0.10 ± 0.06 to 0.26 ± 0.09; olivine: clinopyroxene = 0.10 ± 0.05 to 0.27 ± 0.14). The H2O/(H2O + CO2) molar ratios obtained by comparing the CO2 contents of FI to the H2O amount retained in pyroxene lattices vary between 0.72 ± 0.17 and 0.97 ± 0.03, which is well comparable with the values measured in olivine-hosted melt inclusions from Antarctic primary lavas and assumed as representative of the partition of volatiles at the local mantle conditions. From the relationships between mineral chemistry, thermo-, oxybarometric results and CO2 contents in mantle xenoliths, we speculate that relicts of CO2-depleted mantle are present at Greene Point, representing memory of a CO2-poor tholeiitic refertilization related to the development of the Jurassic Ferrar large magmatic event. On the other hand, a massive mobilization of CO2 took place before the (melt-related) formation of amphibole veins during the alkaline metasomatic event associated with the Cenozoic rift-related magmatism, in response to the storage and recycling of CO2-bearing materials into the Antarctica mantle likely induced by the prolonged Ross subduction.
    Description: Published
    Description: 106643
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: 4V. Processi pre-eruttivi
    Description: 2TR. Ricostruzione e modellazione della struttura crostale
    Description: JCR Journal
    Keywords: CO2 storage ; Sub-Continental Lithospheric Mantle ; Alkaline metasomatism ; Fluid inclusions ; Synchrotron X-ray microtomography ; Inter-granular fluids ; 04.01. Earth Interior ; 04.08. Volcanology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Publication Date: 2022-03-07
    Description: The study concerns the analysis of 220Rn (thoron) recorded in the surface soil in two sites of the Campi Flegrei caldera (Naples, Southern Italy) characterized by phases of volcanic unrest in the seven-year period 1 July 2011–31 December 2017. Thoron comes only from the most surface layer, so the characteristics of its time series are strictly connected to the shallow phenomena, which can also act at a distance from the measuring point in these particular areas. Since we measured 220Rn in parallel with 222Rn (radon), we found that by using the same analysis applied to radon, we obtained interesting information. While knowing the limits of this radioisotope well, we highlight only the particular characteristics of the emissions of thoron in the surface soil. Here, we show that it also shows some clear features found in the radon signal, such as anomalies and signal trends. Consequently, we provide good evidence that, in spite of the very short life of 220Rn compared to 222Rn, both are related to the carrier effect of CO2, which has significantly increased in the last few years within the caldera. The hydrothermal alterations, induced by the increase in temperature and pressure of the caldera system, occur in the surface soils and significantly influence thoron’s power of exhalation from the surface layer. The effects on the surface thoron are reflected in both sites, but with less intensity, the same behavior of 222Rn following the increasing movements and fluctuations of the geophysical and geochemical parameters (CO2 flux, fumarolic tremor, background seismicity, soil deformation). An overall linear correlation was found between the 222−220Rn signals, indicating the effect of the CO2 vector. The overall results represent a significant step forward in the use and interpretation of the thoron signal.
    Description: Published
    Description: 5809
    Description: 4V. Processi pre-eruttivi
    Description: JCR Journal
    Keywords: 220Rn ; volcanic unrest ; hydrothermal alteration ; CO2 ; anomaly and trend ; Campi Flegrei
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 2022-03-07
    Description: Here, we describe the dataset of seismic envelopes used to study the S-wave Q-coda attenuation quality factor Qc of the Gargano Promontory (Southern Italy). With this dataset, we investigated the crustal seismic attenuation by the Qc parameter. We collected this dataset starting from two different earthquake catalogues: the first regarding the period from April 2013 to July 2014; the second regarding the period from July 2015 to August 2018. Visual inspection of the envelopes was carried out on recordings filtered with a Butterworth two-poles filter with central frequency fc = 6 Hz. The obtained seismic envelopes of coda decay can be linearly fitted in a bilogarithmic diagram in order to obtain a series of single source-receiver measures of Qc for each seismogram component at different frequency fc. The analysis of the trend Qc(fc) gives important insights into the heterogeneity and the anelasticity of the sampled Earth medium.
    Description: Published
    Description: 98
    Description: 4T. Sismicità dell'Italia
    Description: JCR Journal
    Keywords: Seismicity Seismic Envelopes ; Seismological data
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 2022-03-07
    Description: As a result of changes in approach from traditional to virtual banking system, security in data exchange has become more important; thus, it seems essentially necessary to present a pattern based on smart models in order to reduce fraud in this field. A new algorithm has been provided in this article to improve security and to specify the limits of giving special services to Internet banking users in order to pave appropriate ground for virtual banking. In addition to identifying behavioral models of customers, this algorithm compares the behaviors of any customer with this model and finally computes the rate of trust in customer’s behavior. The hybrid data-mining and knowledge based structure has been adapted in this algorithm according to fuzzy systems. In this research, qualitative data was gathered from interviews with banking experts, analyzed by Expert Choice to identify the most important variables of customer behavior analysis, and to analyze customer behavior and customer bank Internet transaction data for a period of one year by MATLAB and Clementine. The results of this survey indicate that the potential of the given structure to recognize the rate of trust in Internet bank user’s behavior might be at reasonable level for experts in this area.
    Description: Published
    Description: 916
    Description: 3IT. Calcolo scientifico
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2022-03-07
    Description: The investigation of submerged speleothems for sea level studies has made significant contributions to the understanding of the global and regional sea level variations during the Middle and Late Quaternary. This has especially been the case for the Mediterranean Sea, where more than 300 submerged speleothems sampled in 32 caves have been analysed so far. Here, we present a comprehensive review of the results obtained from the study of submerged speleothems since 1978. The studied speleothems cover the last 1.4 Myr and are mainly focused on Marine Isotope Stages (MIS) 1, 2, 3, 5.1, 5.3, 5.5, 7.1, 7.2, 7.3, and 7.5. The results reveal that submerged speleothems represent extraordinary archives providing accurate information on former sea level changes. New results from a stalagmite collected at Palinuro (Campania, Italy) and characterized by marine overgrowth are also reported. The measured elevations of speleothems are affected by the local response to glacial and hydro-isostatic adjustment (GIA), and thus might significantly deviate from the global eustatic signal. A comparison of the ages and altitude values of the Mediterranean speleothems and flowstone from the Bahamas with local GIA provides a new scenario for MIS 5 and 7 sea level reconstructions
    Description: Published
    Description: 77
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Keywords: Mediterranean Sea; submerged speleothems; phreatic speleothems; sea level change; coastal caves; GIA ; sea level
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2022-03-07
    Description: Areas of the Mediterranean Sea are dynamic habitats in which human activities have been conducted for centuries and which feature micro-tidal environments with about 0.40 m of range. For this reason, human settlements are still concentrated along a narrow coastline strip, where any change in the sea level and coastal dynamics may impact anthropic activities. We analyzed light detection and ranging (LiDAR) and Copernicus Earth observation data. The aim of this research is to provide estimates and detailed maps (in three coastal plain of Sardinia (Italy) and in the Pontina Plain (southern Latium, Italy) of: (i) the past marine transgression occurred during MIS 5.5 highstand 119 kyrss BP; (ii) the coastline regression occurred during the last glacial maximum MIS 2 (21.5 krs cal BP); and (iii) the potential marine submersion for 2100 and 2300. The objective of this multidisciplinary study is to provide maps of sea level rise future scenarios using the IPCC RCP 8.5 2019 projections and glacio-hydro-isostatic movements for the above selected coastal zones (considered tectonically stable), which are the locations of touristic resorts, railways and heritage sites. We estimated a potential loss of land for the above areas of between about 146 km2 (IPCC 2019-RCP8.5 scenario) and 637 km2 along a coastline length of about 268 km.
    Description: Published
    Description: 2597
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Keywords: central Mediterranean coastal plains; past (MIS 5.5) and future sea level at 2100 and 2300; Sardinia; Pontina Plain ; sea level
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Publication Date: 2022-03-07
    Description: Understanding the sources of potentially toxic elements (PTEs) in soils is a worldwide challenge that requires effective discrimination between geogenic and anthropogenic contributions, particularly in areas with certain geological complexity. This study aims to examine the chemical contents of 23 topsoil samples collected from the surroundings of a fossil fuel power plant in the village of Puerto Libertad (Sonoran Desert, Mexico). The study did not exclusively focus on the source identification of the priority PTEs to evaluate soil pollution. Furthermore, major oxides and immobile trace element (Zr, Hf, and REE: La→Lu) data were provided for a reliable assessment of the provenance of the soils. The relatively high SiO2 contents (65.26–75.42 wt%, anhydrous basis), the Post-Archean Australian Shale (PAAS)-normalized REE patterns, and the uniformity of the values of the Index of Compositional Variability (ICV = 1.11–2.72) and the Chemical Index of Alteration (CIA = 31.65–51.79) suggest that the soils were derived from intermediate to felsic source rocks, controlled by the local weathering of the parent bedrocks, under a low degree of chemical weathering conditions. The PTE data were treated following a robust workflow, which included the use of the enrichment factor (EF), the Spearman rank correlation (ρ), and multivariate statistical analyses allowed the generation of significant elemental associations and the identification of pools related either to the geological background or to anthropogenic activities. The results suggesting that Mo and Zn concentrations present a moderate anthropogenic influence while the concentrations of Pb, Sn, Cu, Cd, As, Cr, and Co are predominantly of geogenic origin. Vanadium (avg. EFV = 3.4) and Ni (avg. EFNi = 4.6) were the most enriched elements in the soils. Moreover, the highest values of the integrated Nemerow Pollution Index (PIN〉3) were recorded at the sampling stations closer to the village, suggesting point-source pollution by the emissions of the power station. Finally, in this paper is traced the extent of the particulate released into the atmosphere, which can be dispersed in a wide area into the Sonoran Desert.
    Description: Published
    Description: 105158
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Environmental geochemistry ; Geogenic sources ; Anthropogenic impact ; Provenance ; Power plant pollution ; Puerto libertad ; PTEs ; Solid Earth
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Publication Date: 2022-03-07
    Description: Comprehensive hydrogeochemical studies have been conducted in the Campi Flegrei volcanic aquifer since late 20th century due to the volcanic unrest. In the last decade, groundwater samples were grouped based on the dominant anion species (i.e. bicarbonate, sulfate and chloride) to explain the general hydrogeochemical processes. In this article, 44 groundwater samples are collected from Campi Flegrei aquifer to geochemically and spatially capture the main characteristics of the groundwater body. The hierarchical clustering algorithm is then performed on proportion of bicarbonate, sulfate and chloride, and the optimum number of clusters are determined regarding the results of deep hydrogeochemical investigations published in the past. The collected samples are categorized in the following groups: (1) bicarbonate-rich groundwater; (2) chlorine-rich groundwater; (3) sulfate-rich groundwater; and (4) mixed groundwater. The first group (As = 158.2 ± 169 μg/l, electric conductivity = 1,732.1 ± 1,086 μS/cm and temperature = 25.6 ± 8 ◦C) is mainly derived from poor arsenic meteoric water, but there is significant thermal/seawater contribution in the second one (As = 1,457.8 ± 2,210 μg/l, electric conductivity = 20,118.3 ± 11,139 μS/cm and temperature = 37.1 ± 20 ◦C). Interaction of the bicarbonate-rich groundwater and hydrothermal vapors gives rise to the sulfate-rich groundwater (As = 847.2 ± 679 μg/l, electric conductivity = 3,940.0 ± 540 μS/cm and temperature = 82.8 ± 3 ◦C) around Solfatara volcano. The mixed groundwater (As = 451.4 ± 388 μg/l, electric conductivity = 4,482.9 ± 4,027 μS/cm and temperature = 37.1 ± 16 ◦C) is observed where the three main groundwater groups undergo a mixing process, depending on the hydrogeology of the volcanic aquifer. Contrary to the bicarbonate- and sulfate-rich groundwater, the chlorine-rich and mixed groundwater generally occurs at low piezometric levels (approximately 〈1 m above sea level) near the coastline. The hierarchical cluster analysis provides more information about the volcanic aquifer, particularly when compositional data analysis is applied to study hydrogeochemistry of the homogeneous groundwater groups and to uncover the relationships between variables. Addressing compositional nature of data is recommended in the future studies for developing new tools that help deeper understanding of groundwater evolution in volcanic aquifers and identifying promising precursors of volcanic eruption.
    Description: Published
    Description: 106922
    Description: 4V. Processi pre-eruttivi
    Description: 2IT. Laboratori analitici e sperimentali
    Description: JCR Journal
    Keywords: Hierarchical cluster analysis ; Groundwater evolution ; Hydrothermal system ; Precursors of volcanic eruption ; 03.02. Hydrology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Publication Date: 2022-03-14
    Description: The size and shape of snow grains directly impacts the reflection by a snowpack. In this article, different approaches to retrieve the optical-equivalent snow grain size (ropt) or, alternatively, the specific surface area (SSA) using satellite, airborne, and ground-based observations are compared and used to evaluate ICON-ART (ICOsahedral Nonhydrostatic—Aerosols and Reactive Trace gases) simulations. The retrieval methods are based on optical measurements and rely on the ropt-dependent absorption of solar radiation in snow. The measurement data were taken during a three-week campaign that was conducted in the North of Greenland in March/April 2018, such that the retrieval methods and radiation measurements are affected by enhanced uncertainties under these low-Sun conditions. An adjusted airborne retrieval method is applied which uses the albedo at 1700 nm wavelength and combines an atmospheric and snow radiative transfer model to account for the direct-to-global fraction of the solar radiation incident on the snow. From this approach, we achieved a significantly improved uncertainty (〈25%) and a reduced effect of atmospheric masking compared to the previous method. Ground-based in situ measurements indicated an increase of ropt of 15 μm within a five-day period after a snowfall event which is small compared to previous observations under similar temperature regimes. ICON-ART captured the observed change of ropt during snowfall events, but systematically overestimated the subsequent snow grain growth by about 100%. Adjusting the growth rate factor to 0.012 μm2 s�1 minimized the difference between model and observations. Satellite-based and airborne retrieval methods showed higher ropt over sea ice (〈300 μm) than over land surfaces (〈100 μm) which was reduced by data filtering of surface roughness features. Moderate- Resolution Imaging Spectroradiometer (MODIS) retrievals revealed a large spread within a series of subsequent individual overpasses, indicating their limitations in observing the snow grain size evolution in early spring conditions with low Sun.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Publication Date: 2022-03-09
    Description: The eruptions of Campi Flegrei (Southern Italy), one of the most studied and dangerous active volcanic areas of the world, are fed by mildly potassic alkaline magmas, from shoshonite to trachyte and phonotrachyte. Petrological investigations carried out in past decades on Campi Flegrei rocks provide crucial information for understanding differentiation processes in its magmatic system. However, the compositional features of rocks are a palimpsest of many processes acting over timescales of 100–104 years, including crystal entrapment from multiple reservoirs with different magmatic histories. In this work, olivine, clinopyroxene and feldspar crystals from volcanic rocks related to the entire period of Campi Flegrei’s volcanic activity are checked for equilibrium with combined and possibly more rigorous tests than those commonly used in previous works (e.g., Fe–Mg exchange between either olivine or clinopyroxene and melt), with the aim of obtaining more robust geothermobarometric estimations for the magmas these products represent. We applied several combinations of equilibrium tests and geothermometric and geobarometric methods to a suite of rocks and related minerals spanning the period from ~59 ka to 1538 A.D. and compared the obtained results with the inferred magma storage conditions estimated in previous works through different methods. This mineral-chemistry investigation suggests that two prevalent sets of T–P (temperature–pressure) conditions, here referred to as “magmatic environments”, characterized the magma storage over the entire period of Campi Flegrei activity investigated here. These magmatic environments are ascribable to either mafic or differentiated magmas, stationing in deep and shallow reservoirs, respectively, which interacted frequently, mostly during the last 12 ka of activity. In fact, open-system magmatic processes (mixing/mingling, crustal contamination, CO2 flushing) hypothesized to have occurred before several Campi Flegrei eruptions could have removed earlier-grown crystals from their equilibrium melts. Moreover, our new results indicate that, in the case of complex systems such as Campi Flegrei’s, in which different pre-eruptive processes can modify the equilibrium composition of the crystals, one single geothermobarometric method offers little chance to constrain the magma storage conditions. Conversely, combined methods yield more robust results in agreement with estimates obtained in previous independent studies based on both petrological and geophysical methods
    Description: Published
    Description: 308
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Publication Date: 2022-03-14
    Description: On Vulcano Island (Italy), many geochemical crises have occurred during the last 130 years of solfataric activity. The main crises occurred in 1978–1980, 1988–1991, 1996, 2004–2007, 2009–2010 and the ongoing 2021 anomalous degassing activity. These crises have been characterized by early signals of resuming degassing activity, measurable by the increase of volatiles and energy output emitted from the summit areas of the active cone, and particularly by increases of gas/water ratios in the fumarolic area at the summit. In any case, a direct rather than linear correspondence has been observed among the observed increase in the fluid output, seismic release and ground deformation, and is still a subject of study. We present here the results obtained by the long-term monitoring (over 13 years of observations) of three extensive parameters: the SO2 flux monitored in the volcanic plume, the soil CO2 flux and the local heat flux, monitored in the mild thermal anomaly located to the east of the high-temperature fumarole. The time variations of these parameters showed cyclicity in the volcanic degassing and a general increase in the trend in the last period. In particular, we focused on the changes in the mass and energy output registered in the period of June–December 2021, to offer in near-real-time the first evaluation of the level and duration of the actual exhalative crisis affecting Vulcano Island. In this last event, a clear change in degassing style was recorded for the volatiles emitted by the magma. For example, the flux of diffused CO2 from the soils reached the maximum never-before-recorded value of 34,000 g m−2 d −1 and the flux of SO2 of the plume emitted by the fumarolic field on the summit crater area reached values higher than 200 t d−1 . The interpretation of the behavior of this volcanic system, resulting from the detailed analyses of these continuous monitoring data, will complete the framework of observations and help in defining and possibly forecasting the next evolution of the actual exhaling crisis.
    Description: This research was funded by the INGV-DPCN (Italian National Institute of Geophysics and Volcanology—Italian National Department for Civil Protection) volcanic surveillance program of Vulcano island, ObFu 0304.010. Moreover, this investigation was partially funded by the TORS project in the framework of institutional INGV projects “Ricerca Libera” ObFu 9999.549; and Pianeta Dinamico Task V2, ObFu 1020.010.
    Description: Published
    Description: 1283
    Description: 4V. Processi pre-eruttivi
    Description: JCR Journal
    Keywords: : SO2 flux; CO2 flux; heat flux; Vulcano Island; geochemical crisis; extensive parameters
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Publication Date: 2022-05-02
    Description: We assess about 20 years of onshore and offshore subsidence along a sector of the Upper Adriatic Sea (Italy) coastal areas affected by natural soil compaction and intense anthropogenic activities such as aquifers exploitation and hydrocarbons extraction. Our approach is based on the synergistic use of independent remote sensing and in-situ geodetic data to detect and spatially characterise the deformation pattern by cross-validating the different available measurements. We collect extensive datasets from i) SAR images provided by Envisat, Cosmo- SkyMed and Sentinel-1 missions, ii) GNSS measurements from continuous stations managed by public institutions, local authorities and private companies and iii) Leveling surveys. The cross-validation analysis shows good agreement among all the independent datasets, thus providing a reliable assessment of the ongoing deformation. We detect an onshore and offshore subsidence peak of about 1/-1.5 cm/yr in the proximity of the coastline, close to Lido di Dante and Fiumi Uniti villages, and at the present offshore platform. The outcomes highlight how the integration of different remote sensing and in situ geodetic techniques is successful to retrieve deformation history in time and space in complex areas, where different natural and anthropogenic sources concur to the overall deformation pattern. Moreover, such approach provides a robust support to modelling studies for hazard assessment in both inland and shoreline areas.
    Description: Published
    Description: 102756
    Description: 1TR. Georisorse
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Publication Date: 2022-05-02
    Description: The potential of shortwave infrared (SWIR) remote sensing to detect hotspots has been investigated using satellite data for decades. The hotspots detected by satellite SWIR sensors include very high-temperature heat sources such as wildfires, volcanoes, industrial activity, or open burning. This study proposes an automated classification method of heat source detected utilizing Landsat 8 and Sentinel-2 data. We created training data of heat sources via visual inspection of hotspots detected by Landsat 8. A scheme to classify heat sources for daytime data was developed by combining classification methods based on a Convolutional Neural Network (CNN) algorithm utilizing spatial features and a decision tree algorithm based on thematic land-cover information and our time series detection record. Validation work using 10,959 classification results corresponding to hotspots acquired from May 2017 to July 2019 indicated that the two classification results were in 79.7% agreement. For hotspots where the two classification schemes agreed, the classification was 97.9% accurate. Even when the results of the two classification schemes conflicted, either was correct in 73% of the samples. To improve the accuracy, the heat source category was re-allocated to the most probable category corresponding to the combination of the results from the two methods. Integrating the two approaches achieved an overall accuracy of 92.8%. In contrast, the overall accuracy for heat source classification during nighttime reached 79.3% because only the decision tree-based classification was applicable to limited available data. Comparison with the Visible Infrared Imaging Radiometer Suite (VIIRS) fire product revealed that, despite the limited data acquisition frequency of Landsat 8, regional tendencies in hotspot occurrence were qualitatively appropriate for an annual period on a global scale.
    Description: Published
    Description: 102491
    Description: 7A. Geofisica per il monitoraggio ambientale
    Description: JCR Journal
    Keywords: Landsat 8 OLISentinel-2 Thermal anomaly,Wildfire,Volcano,CNN,Time serie
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2022-04-22
    Description: We describe the diagnostic lithological and chemical features of distal tephras from major MiddleLate Pleistocene (560e36 ka) explosive eruptions of the Colli Albani volcanic district, central Italy. In particular, we explore the time-dependent variability of the Sr and Nd isotope compositions as a tool for recognising and pinpointing individual Colli Albani tephra in distal settings. The distal tephras investigated are in lacustrine and fluvial sediments of central Apennine intermountain basins located 70 kme100 km east of Colli Albani. The recognition of the Colli Albani tephras is essentially based on the K-foiditic composition of their glass, which, within the Italian volcanological framework, is a distinctive character of the Colli Albani pyroclasts. In detail, these tephras are attributed to the following eruptive units: Tufo Pisolitico di Trigoria (561 2 ka); Tufo del PalatinoeTufo di Bagni Albule (530 2/527 2 ka), Tufo di Bagni AlbuleePozzolane Rosse air-fall sequence (517 1 to 500 3 ka), Pozzolane Rosse (457 4 ka), Villa Senni (365 4 ka), and Albano 5e7 (41 7 to 36 1 ka). These correlations are supported by 40Ar/39Ar dating of the distal tephras correlated to the Pozzolane Rosse (457.4 1.7 ka), Villa Senni (365 2 ka) and Albano 5e7 (41 9 ka) and by 87Sr/86Sr measured on clinopyroxene crystals and fresh glassy scoria from distal Colli Albani tephras that range from w0.711 to w0.709. These ratios are similar to those that characterise the individual proximal correlative units, and show the same decreasing trend over time. In contrast, the 143Nd/144Nd ratios for proximal and distal bulk samples and clinopyroxene increase from w0.51212 to w0.51215 from the oldest to the youngest tephra deposit. In summary, the study of Sr and Nd isotope compositions that is here applied on products from the Colli Albani volcanic district is a powerful, complementary tool to the more traditional tephrostratigraphic methods (e.g., componentry and electron microprobe analysis) for fingerprinting of distal tephras over a large region of the central Mediterranean, and over a large time interval, such as from 560 ka to 36 ka.
    Description: Published
    Description: 190-206
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: 4V. Processi pre-eruttivi
    Description: JCR Journal
    Keywords: Ultra-potassic tephra markers ; Roman Comagmatic Province ; Major elements glass compositions ; Isotopic 87Sr/86Sr and 143Nd/144Nd
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Publication Date: 2022-04-22
    Description: An accurate understanding of dissimilarities in geomagnetic variability between quiet and disturbed periods has the potential to vastly improve space weather diagnosis. In this work, we exploit some recently developed methods of dynamical system theory to provide new insights and conceptual ideas in space weather science. In particular, we study the co-variation and recurrence statistics of two geomagnetic indices, SYM-H and AL, that measure the intensity of the globally symmetric component of the equatorial electrojet and that of the westward auroral electrojet, respectively. We find that the number of active degrees of freedom, required to describe the phase space dynamics of both indices, depends on the geomagnetic activity level. When the magnetospheric substorm activity, as monitored by the AL index, increases, the active number of degrees of freedom increases at high latitudes above the dimension obtained through classical time delay embedding methods. Conversely, a reduced number of degrees of freedom is observed during geomagnetic storms at low latitude by analysing the SYM-H index. By investigating time-dependent relations between both indices we find that a significant amount of information is shared between high and low latitude current systems originating from coupling mechanisms within the magnetosphere–ionosphere system as the result of a complex interplay between processes and phenomena of internal origin activated by the triggering of external source processes. Our observations support the idea that the near-Earth electromagnetic environment is a complex system far from an equilibrium
    Description: Published
    Description: 226
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: JCR Journal
    Keywords: Space weather ; geomagnetic storms ; magnetospheric substorms ; geomagnetic indices ; 04.05. Geomagnetism
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Publication Date: 2022-04-21
    Description: The dynamics of magma is often studied through 2D numerical simulations because 3D simulations are usually complex and computationally expensive. However, magmatic systems and physical processes are 3D and approximating them in 2D requires an evaluation of the information which is lost under different conditions. This work presents a physical and numerical model for 3D magma convection dynamics. The model is applied to study the dynamics of magma convection and mixing between andesitic and dacitic magmas. The 3D simulation results are compared with corresponding 2D simulations. We also provide details on the numerical scheme and its parallel implementation in C++ for high-performance computing. The performance of the numerical code is evaluated through strong scaling exercises involving up to 〉 12,000 cores.
    Description: Published
    Description: 760773
    Description: 4V. Processi pre-eruttivi
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Publication Date: 2022-04-22
    Description: The recent Chinese Seismo-Electromagnetic Satellite (CSES-01) provides a good opportunity to investigate some features of plasma properties and its motion in the topside ionosphere. Using simultaneous measurements from the electric field detector and the magnetometers onboard CSES-01, we investigate some properties of the plasma ExB drift velocity for a case study during a crossing of the Southern auroral region in the topside ionosphere. In detail, we analyze the spectral and scaling features of the plasma drift velocity and provide evidence of the turbulent character of the ExB drift. Our results provide an evidence of the occurrence of 2D ExB intermittent convective turbulence for the plasma motion in the topside ionospheric F2 auroral region at scales from tens of meters to tens of kilometers. The intermittent character of the observed turbulence suggests that the macro-scale intermittent structure is isomorphic with a quasi-1D fractal structure, as happens, for example, in the case of a filamentary or thin-tube-like structure. Furthermore, in the analyzed range of scales we found that both magnetohydrodynamic and kinetic processes may affect the plasma dynamics at spatial scales below 2 km. The results are discussed and compared with previous results reported in the literature.
    Description: Published
    Description: 1936
    Description: 2A. Fisica dell'alta atmosfera
    Description: JCR Journal
    Keywords: Turbulence ; Auroral ionosphere ; ExB plasma motion ; 01.02. Ionosphere
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Publication Date: 2022-04-26
    Description: Constraining the magmatic 3He/4He signature of fluids degassed from a magmatic system is crucial for making inferences on its mantle source. This is especially important in arc volcanism, where variations in the composition of the wedge potentially induced by slab sediment fluids must be distinguished from the effects of magma differentiation, degassing, and crustal contamination. The study of fluid inclusions (FIs) trapped in minerals of volcanic rocks is becoming an increasingly used methodology in geochemical studies that integrates the classical study of volcanic and geothermal fluids. Here, we report on the first noble gas (He, Ne, Ar) concentrations and isotopic ratios of FI in olivine (Ol) and pyroxene (Px) crystals separated from eruptive products of the Telica and Baru volcanoes, belonging to the Nicaraguan and Panamanian arc-segments of Central America Volcanic arc (CAVA). FIs from Telica yield air corrected 3He/4He (Rc/Ra) of 7.2–7.4 Ra in Ol and 6.1–7.3 in Px, while those from Baru give 7.1–8.0 Ra in Ol and 4.2–5.8 Ra in Px. After a data quality check and a comparison with previous 3He/4He measurements carried out on the same volcanoes and along CAVA, we constrained a magmatic Rc/Ra signature of 7.5 Ra for Telica and of 8.0 Ra for Baru, both within the MORB range (8 1 Ra). These 3He/4He differences also reflect variations in the respective arc-segments, which cannot be explained by radiogenic 4He addition due to variable crust thickness, as the mantle beneath Nicaragua and Panama is at about 35 and 30 km, respectively. We instead highlight that the lowest 3He/4He signature observed in the Nicaraguan arc segment reflects a contamination of the underlying wedge by slab sediment fluids. Rc/Ra values up to 9.0 Ra are found at Pacaya volcano in Guatemala, where the crust is 45 km thick, while a 3He/4He signature of about 8.0 Ra was measured at Turrialba volcano in Costa Rica, which is similar to that of Baru, and reflects possible influence of slab melting, triggered by a change in subduction conditions and the contemporary subduction of the Galapagos hot-spot track below southern Costa Rica and western Panama.
    Description: Published
    Description: 2076-3417
    Description: 1V. Storia eruttiva
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: JCR Journal
    Keywords: Telica volcano ; Baru volcano ; 3He/4He ; fluid inclusions ; CAVA ; slab fluids ; Isotope Geochemistry ; Noble gases ; 04.08. Volcanology ; 04.01. Earth Interior
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Publication Date: 2022-04-28
    Description: Geogenic and anthropogenic sources of atmospheric particulate and CO2 can lead to threats to human health in volcanic areas. Although the volcanic CO2 hazard is a topic frequently debated in the related scientific literature, space and time distribution of PM2.5 are poorly known. The results of combined CO2/PM2.5 surveys, carried out at Salina, Stromboli, and Vulcano islands (Aeolian archipelago, Italy) in the years 2020-2021, and integrated with investigations on bioaccumulation of metallic particulate matter by the mean of data on the magnetic properties of oleander leaves, are presented in this work. The retrieved results indicate that no significant anthropogenic sources for both CO2 and PM2.5 are active in these islands, at the net of a minor contribution due to vehicular traffic. Conversely, increments in volcanic activity, as the unrest experienced by Vulcano island since the second half of 2021, pose serious threats to human health, due to the near-ground accumulation of CO2, and the presence of suspended micro-droplets of condensed hydrothermal vapor, fostering the diffusion of atmophile viruses, such as the COVID-19. Gas hazard conditions can be generated, not only by volcanic vents or fumarolic fields, but also by unconventional sources, such as the outgassing from shallow hydrothermal aquifers through drilled or hand-carved wells.
    Description: Published
    Description: 4833
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Aeolian Islands; gas hazard; magnetic properties; plant leaves; volcanic ash; volcanic unrest
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Publication Date: 2022-04-29
    Description: We carried out new geological, morphotectonic, geophysical and paleoseismological investigations on the Meduno Thrust that belongs to the Pliocene-Quaternary front of the eastern Southern Alps in Friuli (NE Italy). The study area is located in the Carnic Prealps, where a series of alluvial terraces, linked to both climatic and tectonic pulses characterises the lower reach of the Meduna Valley. In correspondence of the oblique ramp of the Meduno Thrust, the Late Pleistocene Rivalunga terrace shows a set of scarps perpendicular to the Meduno valley, often modified by human activity. In order to reconstruct the tectonic setting of the area and identify the location for digging paleoseismological trenches, integrated geophysical investigations including electrical resistivity tomography, seismic refraction and reflection, ground penetrating radar and surface wave analyses (HVSR, ReMi and MASW), were carried out across the scarps of the Rivalunga terrace. Geophysical surveys pinpointed that in correspondence of the oblique ramp, stress is accommodated by a transpressive thrust system involving all the seismo-stratigraphic horizons apart from the ploughed soil. Trenching illustrated the Meduno Thrust movements during Late Pleistocene-Holocene. Trenches exhibited both shear planes and extrados fracturing, showing deformed alluvial and colluvial units. 14C datings of the colluvial units show that the most recent fault movements occurred after 1360 CE and 1670 CE. The age of the deformed stratigraphic units compared with the earthquakes listed in current catalogues, suggests that the 1776 earthquake (Mw 5.8, Io = 8–9 MCS) could represent the last seismic event linked to the Meduno thrust activity. This study provided new quantitative constraints improving seismic hazard assessment for Carnic prealpine area.
    Description: The research developed in the framework of the agreement between the Regione Autonoma Friuli Venezia Giulia - Direzione Centrale Ambiente ed Energia - Servizio Geologico, the Istituto Superiore per la Protezione e la Ricerca Ambientale (I.S.P.R.A.) and the University of Udine. The project was funded by the Regione Autonoma Friuli Venezia Giulia, Direzione Centrale Ambiente ed Energia, Servizio Geologico (C.I. G.: Z0E0C5EF75, p.i. Maria Eliana Poli).
    Description: Published
    Description: 229071
    Description: 2T. Deformazione crostale attiva
    Description: JCR Journal
    Keywords: Active fault ; Paleoseismology ; Morphogenic earthquake ; Eastern Southern Alps ; Applied geophysics ; NE Italy ; 04.04. Geology ; 04.07. Tectonophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Publication Date: 2022-04-29
    Description: We identify the source of the Mw = 6.4 earthquake that rocked north-central Albania on November 26, 2019 02:54 UTC. We use synthetic aperture radar interferograms tied to the time series of coordinates of two permanent Global Navigation Satellite System (GNSS) stations (DUR2 and TIR2). We model the source by inverting the displacement data. Assuming in our model a half-space elastic medium and uniform slip along a rectangular fault surface, we invert the 104 picked measurements on a couple of ascending and descending interferograms to calculate the parameters of the fault. All inversions made with di erent input parameters converge towards a stable and robust solution with root mean square (r.m.s.) residual of 5.4 mm, thus ~1/5 of a fringe. They reveal that the earthquake occurred deep in the crust on a low-angle fault (23 ) dipping towards east with a centroid at 16.5 km depth. The best-fitting length and width of the fault are 22 and 13 km, and the reverse slip, 0.55 m. The seismic moment deduced from our model agrees with those of the published seismic moment tensors. This geometry is compatible with a blind thrust fault that may root on the main basal thrust, i.e., along the thrust front that separates Adria–Apulia from Eurasia. It is notable that there is a 123 ns yr-1 active shortening of the crust between the GNSS stations DUR2-TIR2 (equivalent to a shortening rate of 3.6 mm yr-1), and roughly in the east–west direction. Given this amount of strain the recurrence time of M6+ earthquakes along this fault should be of the order of 150 years.
    Description: Published
    Description: 210
    Description: 3T. Sorgente sismica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Publication Date: 2022-05-03
    Description: Rocky reefs provide complex structures in the otherwise largely sand-dominated coastal North Sea. Therefore, these reefs are highly important natural habitats for the functioning of coastal ecosystems, as they provide shelter, refuge and nursery grounds for various mobile and sessile species. In the North Sea, the spatial distribution of these habitats has been intensively investigated over recent years. However, these studies generally provide static accounts of the current state of these reef systems, but limited data exist on the temporal variations in sediment dynamics at and around natural rocky reefs. In this study, we provide observations from a multiannual time series of hydroacoustic seafloor surveys conducted at an isolated rocky reef in the North Sea. We use multibeam bathymetry and side-scan sonar backscatter data in combination with video observations, sediment sampling, and sub-bottom profiler data to assess the long-term variations of the rocky reef system. The reef is located in water depths between 11 and 17 m with an areal extent of ~0.5 km2 and is surrounded by mobile sands. The topography of the rocky reef appears to create a distinct hydrodynamic system that permits mobile sands to settle or move into bathymetrical deeper parts of the reef. Our results suggest a very dynamic system surrounding the reef with large scale scouring, sediment reworking and transport, while the shallower central part of the reef remains stable over time. We demonstrate the importance of hydrodynamics and current scouring around reefs for the local variability in seafloor properties over time. These small-scale dynamics are likewise reflected in the spatial distribution of sessile species, which are less abundant in proximity to mobile sands. The hydroacoustic mapping and monitoring of seafloor dynamics at higher spatial and temporal resolutions presents an important future direction in the study of valuable coastal habitats.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Publication Date: 2022-05-25
    Description: Author Posting. © American Meteorological Society, 2020. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 33(9), (2020): 3845-3862, doi:10.1175/JCLI-D-19-0215.1.
    Description: The latitudinal structure of the Atlantic meridional overturning circulation (AMOC) variability in the North Atlantic is investigated using numerical results from three ocean circulation simulations over the past four to five decades. We show that AMOC variability south of the Labrador Sea (53°N) to 25°N can be decomposed into a latitudinally coherent component and a gyre-opposing component. The latitudinally coherent component contains both decadal and interannual variabilities. The coherent decadal AMOC variability originates in the subpolar region and is reflected by the zonal density gradient in that basin. It is further shown to be linked to persistent North Atlantic Oscillation (NAO) conditions in all three models. The interannual AMOC variability contained in the latitudinally coherent component is shown to be driven by westerlies in the transition region between the subpolar and the subtropical gyre (40°–50°N), through significant responses in Ekman transport. Finally, the gyre-opposing component principally varies on interannual time scales and responds to local wind variability related to the annual NAO. The contribution of these components to the total AMOC variability is latitude-dependent: 1) in the subpolar region, all models show that the latitudinally coherent component dominates AMOC variability on interannual to decadal time scales, with little contribution from the gyre-opposing component, and 2) in the subtropical region, the gyre-opposing component explains a majority of the interannual AMOC variability in two models, while in the other model, the contributions from the coherent and the gyre-opposing components are comparable. These results provide a quantitative decomposition of AMOC variability across latitudes and shed light on the linkage between different AMOC variability components and atmospheric forcing mechanisms.
    Description: The authors gratefully acknowledge support from the Physical Oceanography Program of the U.S. National Science Foundation (Awards OCE-1756143 and OCE-1537136) and the Climate Program Office of the National Oceanic and Atmospheric Administration (Award NA15OAR4310088). Gratitude is extended to Claus Böning and Arne Biastoch who shared ORCA025 output. S. Zou thanks F. Li, M. Buckley, and L. Li for helpful discussions. We also thank three anonymous reviewers for helpful suggestions.
    Keywords: Deep convection ; Ocean circulation ; Thermocline circulation
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Publication Date: 2022-05-25
    Description: Author Posting. © American Meteorological Society, 2020. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Hahn, L. C., Storelvmo, T., Hofer, S., Parfitt, R., & Ummenhofer, C. C. Importance of Orography for Greenland cloud and melt response to atmospheric blocking. Journal of Climate, 33(10), (2020): 4187-4206, doi:10.1175/JCLI-D-19-0527.1.
    Description: More frequent high pressure conditions associated with atmospheric blocking episodes over Greenland in recent decades have been suggested to enhance melt through large-scale subsidence and cloud dissipation, which allows more solar radiation to reach the ice sheet surface. Here we investigate mechanisms linking high pressure circulation anomalies to Greenland cloud changes and resulting cloud radiative effects, with a focus on the previously neglected role of topography. Using reanalysis and satellite data in addition to a regional climate model, we show that anticyclonic circulation anomalies over Greenland during recent extreme blocking summers produce cloud changes dependent on orographic lift and descent. The resulting increased cloud cover over northern Greenland promotes surface longwave warming, while reduced cloud cover in southern and marginal Greenland favors surface shortwave warming. Comparison with an idealized model simulation with flattened topography reveals that orographic effects were necessary to produce area-averaged decreasing cloud cover since the mid-1990s and the extreme melt observed in the summer of 2012. This demonstrates a key role for Greenland topography in mediating the cloud and melt response to large-scale circulation variability. These results suggest that future melt will depend on the pattern of circulation anomalies as well as the shape of the Greenland Ice Sheet.
    Description: This research was supported by the Woods Hole Oceanographic Institution Summer Student Fellow program, by the U.S. National Science Foundation under AGS-1355339 to C.C.U., and by the European Research Council through Grant 758005.
    Keywords: Ice sheets ; Blocking ; Cloud cover ; Topographic effects ; Climate change ; Climate variability
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Publication Date: 2022-05-25
    Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Jacox, M. G., Alexander, M. A., Siedlecki, S., Chen, K., Kwon, Y., Brodie, S., Ortiz, I., Tommasi, D., Widlansky, M. J., Barrie, D., Capotondi, A., Cheng, W., Di Lorenzo, E., Edwards, C., Fiechter, J., Fratantoni, P., Hazen, E. L., Hermann, A. J., Kumar, A., Miller, A. J., Pirhalla, D., Buil, M. P., Ray, S., Sheridan, S. C., Subramanian, A., Thompson, P., Thorne, L., Annamalai, H., Aydin, K., Bograd, S. J., Griffis, R. B., Kearney, K., Kim, H., Mariotti, A., Merrifield, M., & Rykaczewski, R. Seasonal-to-interannual prediction of North American coastal marine ecosystems: forecast methods, mechanisms of predictability, and priority developments. Progress in Oceanography, 183, (2020): 102307, doi:10.1016/j.pocean.2020.102307.
    Description: Marine ecosystem forecasting is an area of active research and rapid development. Promise has been shown for skillful prediction of physical, biogeochemical, and ecological variables on a range of timescales, suggesting potential for forecasts to aid in the management of living marine resources and coastal communities. However, the mechanisms underlying forecast skill in marine ecosystems are often poorly understood, and many forecasts, especially for biological variables, rely on empirical statistical relationships developed from historical observations. Here, we review statistical and dynamical marine ecosystem forecasting methods and highlight examples of their application along U.S. coastlines for seasonal-to-interannual (1–24 month) prediction of properties ranging from coastal sea level to marine top predator distributions. We then describe known mechanisms governing marine ecosystem predictability and how they have been used in forecasts to date. These mechanisms include physical atmospheric and oceanic processes, biogeochemical and ecological responses to physical forcing, and intrinsic characteristics of species themselves. In reviewing the state of the knowledge on forecasting techniques and mechanisms underlying marine ecosystem predictability, we aim to facilitate forecast development and uptake by (i) identifying methods and processes that can be exploited for development of skillful regional forecasts, (ii) informing priorities for forecast development and verification, and (iii) improving understanding of conditional forecast skill (i.e., a priori knowledge of whether a forecast is likely to be skillful). While we focus primarily on coastal marine ecosystems surrounding North America (and the U.S. in particular), we detail forecast methods, physical and biological mechanisms, and priority developments that are globally relevant.
    Description: This study was supported by the NOAA Climate Program Office’s Modeling, Analysis, Predictions, and Projections (MAPP) program through grants NA17OAR4310108, NA17OAR4310112, NA17OAR4310111, NA17OAR4310110, NA17OAR4310109, NA17OAR4310104, NA17OAR4310106, and NA17OAR4310113. This paper is a product of the NOAA/MAPP Marine Prediction Task Force.
    Keywords: Prediction ; Predictability ; Forecast ; Ecological forecast ; Mechanism ; Seasonal ; Interannual ; Large marine ecosystem
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Publication Date: 2022-05-04
    Description: Fluid migration along faults can be highly complex and spatially variable, with the potential for channeled flow, accumulation in capped porous units, fault cross-flow, lateral migration along strike, or complete sealing. Extensional basin margins can be important for such migration, given the associated crustal thinning and decompression that takes place combined with potential geothermal or mantle gas sources. One such example is near the urban area of Rome, situated along the active extensional continental margin of the Tyrrhenian back arc basin and surrounded by Middle-Upper Pleistocene K-rich and arc-related volcanoes. Recent research activities in the area around Fiumicino, a town 25 km to the west of Rome, has highlighted the close spatial link between degassing CO2 and the faults that provide the necessary vertical migration pathways. In particular, detailed soil gas and gas flux surveys have highlighted the release at surface of large volumes of asthenospheric mantle CO2 in correspondence with normal faults observed in a new seismic reflection profile acquired along the Tiber River. Detailed reconstruction of the Pleistocene–Holocene stratigraphy of the area dates fault activity from 20,000 to 9000 years BP. It is proposed that the gas migrates preferentially along the cataclastic tectonic breccias of the faults until it encounters recent, unconsolidated sediments; porous units within this shallow stratigraphy act as temporary secondary traps for the leaking gas, with local gas release at the ground surface occurring where the sealing of the overlying aquitards has been compromised. Degassing and active faults confirm the extensional tectonics affecting the area and the geodynamic scenario of a mantle wedge beneath the western Apennines, associated with ongoing W-directed subduction. Moreover, degassing highlights the potential geochemical and seismic risks for the highly populated urban areas near Rome.
    Description: Published
    Description: 137-149
    Description: 9T. Geochimica dei fluidi applicata allo studio e al monitoraggio di aree sismiche
    Description: JCR Journal
    Keywords: soil gas ; Fluid migration ; 04.04. Geology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Publication Date: 2022-05-04
    Description: Time-series analyses of satellite images reveal that sea ice extent in the Ross Sea has experienced significant changes over the last 40 years, likely triggered by large-scale atmospheric anomalies. However, resolving how sea ice in the Ross Sea has changed over longer timeframes has until now remained more elusive. Here we used a laminated sediment piston core (14.6 m) collected from the Edisto inlet (Western Ross Sea) to reconstruct fast ice dynamics over the last 2.6 ka. Our goal was to first understand the climate expression of selected well-defined sediment laminae and then use these characteristics for reconstructing past sea ice behaviour across the whole sedimentary sequence. We used the recently established sea ice diatom biomarker proxy IPSO25 in combination with diatom census counts and bulk analyses. Analyses performed on a suite of discrete laminae revealed statistically significant differences between dark and light laminae reflecting different depositional conditions. Based on their respective biogeochemical fingerprints, we infer that dark laminae accumulated during sea ice thaws in early summer. Under these conditions, laminae contain relatively high concentrations of IPSO25 and display an enriched d13C composition for the bulk organic matter (OM). While diatom assemblages in dark laminae are relatively homogenous, as the thaw continues later in the summer, Corethron pennatum becomes the dominant diatom species, resulting in the formation of light laminae characterized by low IPSO25 concentrations. Since C. pennatum can migrate vertically through the water column to uptake nutrients and avoid competition in oligotrophic waters, its high concentration likely reflects stratified and ice-free surface waters typical of late summer. Down-core trends show that the correlation between sediment brightness and geochemical fingerprint (i.e., IPSO25 and d13C) holds throughout the record. Based on the knowledge gained at lamina level, our down-core high-resolution reconstruction shows that the summer fast ice coverage changed dramatically during the late Holocene. Specifically, we conclude that the Edisto inlet experienced regular early summer opening between 2.6 ka, and ca. 0.7 ka, after which, coastal fast ice persisted during summer months and ice-free conditions became less frequent. Comparison with previous regional ice core data suggests that the sudden cooling recorded over the Victoria Land Coast region since 0.7 ka might potentially explain our observation of persistent summer fast ice in the Western Ross Sea. Our study has shown that multi-proxy data derived from laminated sediments can provide hitherto unknown detail regarding past summer sea ice dynamics in coastal Antarctic regions.
    Description: Published
    Description: 106299
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Keywords: Ross Sea ; Fast ice ; Laminated sediments ; IPSO25 ; Sea ice ; Sea ice dynamics in the north-western Ross Sea
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Publication Date: 2022-03-16
    Description: The fallout of ballistic blocks and bombs ejected from eruptive vents has the potential to produce severe injuries to people and damage to infrastructure in areas proximal to volcanoes. The dimensions and dispersions of ballistic ejecta from explosive eruptions are pivotal parameters to forecast the potential impact associated with future eruptions based on the compilation of probabilistic hazard maps. In this study, we propose a new probabilistic hazard quantification strategy to provide the probability of Volcanic Ballistic Projectiles (VBPs) to exceed some critical kinetic energy thresholds, considering a variability on the site of the eruptive vents and the effect of wind. La Soufrière de Guadeloupe (Lesser Antilles) is chosen as a test case, focussing on the most likely style explosive scenario associated with the eruption of an active lava dome (including phreatic, Vulcanian and Strombolian eruptions). Sensitivity analyses have guided the optimization of input parameters to balance the results stability and computational costs, showing that the topography is a pivotal factor when accounting for the spatial uncertainty on vent locations in the proximity of the dome area. Given an eruption within the adopted scenario, we provide maps showing the probability to exceed different energy reference thresholds for roof's perforation if at least one VBP falls in a target area. These maps are then combined with exposed elements to produce a qualitative exposure-based risk map. We compute the overall probability, conditional on the selected scenario, for roof perforation in a given area when a VBP is ejected. Results show probabilities varying from ca. 2% up to 40% within a few km from the volcano, quickly dropping away from the dome. However, when the probability to exceed the energy reference threshold is only conditional on falling of VBPs in a target area, most of Basse-Terre island would be affected by the 20–60% probability of roof perforation. This work confirms how the choice of a probabilistic approach is key to estimate the likelihood of occurrence of VBPs impacts as a first step towards the development and implementation of pro–active risk reduction strategies in volcanic areas.
    Description: Published
    Description: 107453
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Publication Date: 2022-03-16
    Description: © 〈2021〉. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/
    Description: In this paper we explore the efficiency of various machine learning techniques to determine the volcano source,the eruptive formation and the eruption period of volcanic rocks when their chemical contents are known. Withthis aim, we assembled a data set of 9800 volcanic rocks from the open-access literature. The rocks belong toeruptive formations from Somma-Vesuvius, Campi Flegrei, Ischia and Procida volcanoes, in the Neapolitan regionof Italy.The data set includes content of majoroxidesand trace elements,aswell asSrand Nd isotope ratios,erup-tive periods, eruption formations and volcano source. Some discrete numerical variables are missing in certainsamples resulting in data exclusion and measurement inhomogeneity. Our results indicate that, despite such is-sues, some machine learning algorithms have a very high prediction ability, i.e., at 〉70%. The achieved resultsare interesting in order to facilitate the managing of new data for volcanological reconstruction andtephrostratigraphic studies
    Description: Published
    Description: 107254
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Publication Date: 2022-03-16
    Description: In this study we present the compositional changes of clinopyroxene (cpx), plagioclase (plg), spinel (sp), and glass experimentally solidified from an Icelandic MORB melt. The starting material was cooled at Patm and fO2 of air, in the thermal range of cooling (ΔTc) between 1300 °C (superliquidus) to 800 °C (solidus) with rates (ΔT/Δt) of 1, 7, 60, 180, 1800, and 9000 °C/h. The run products obtained at 1, 7 and 60 °C/h are holocrystalline, whilst between 60 and 180 °C/h plg disappears, and texture of cpx + sp. shifts from faceted to dendritic. As cooling rate increases, we observe that Fe2O3 decreases and Al2O3 increases in sp. and Al2O3 + Fe2O3 increase and CaO + MgO decrease in cpx. These measured variations mirror changes induced by cooling rate in cation (atoms per formula unit, a.p.f.u.) and molecular abundances of these two crystalline phases. Plg composition shows clear linear trends versus cooling rate. The chemistry of sp., cpx and, to a minor extent, plg solidified from this basaltic liquid is thus strictly related to the cooling rate condition and is similar to those observed in previous investigations on alkaline and evolved basaltic systems. In particular, cpx is the only mineral phase profusely present at all the cooling rates, showing the greatest chemical variations in terms of oxides, cations, and components. The intra-crystalline glass (≤ 50 μm from crystal rims) obtained at 180–1800 °C/h shows compositional variations related to the surrounding crystal growth, evidencing strong supersaturation phenomena (such as dendritic texture) due to the establishment of a diffusion-controlled growth regime. Chemical attributes of mineral phases are also quantitatively related with the maximum (Gmax) and average (GCSD) growth rates of sp., cpx, and plg. When compared with the starting melt composition, the chemistry of cpx suggests the attainment of near-equilibrium crystallization conditions at cooling rate ≤ 60 °C/h, whereas disequilibrium effects are found at cooling rate 〉 60 °C/h. In contrast, plg is in disequilibrium with the initial melt chemistry in all experiments. By using thermometric models, the calculated crystallization of plg takes place at temperatures much lower than those of cpx, when the crystal content is high and the diffusion of cations in the melt is slow due to the higher (residual) melt viscosity. Under such conditions and due to the effect of cooling, the system cannot return to homogeneous concentrations and, consequently, plg more effectively records the disequilibrium partitioning of cations between the growing crystal surface. The data-set reported here captures the entire (superliquidus to solidus) and intrinsic (heterogeneous site-free silicate liquid) solidification behavior from an actual MORB melt from very rapid to extremely sluggish cooling rate. Finally, all analytical relationships found in this work enable careful reconstruction of the solidification conditions of MORB melts, providing novel geo-speedometers for them at high fO2.
    Description: Published
    Description: 120765
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Publication Date: 2022-03-16
    Description: Dst (Disturbance Storm Time) is an hourly index of magnetic activity computed from the measured intensity of the globally symmetrical equatorial electrojet (Ring Current) obtained by a series of near-equatorial geomagnetic observatories. We selected and trained an Artificial Neural Network (ANN) to give the estimation of the Dst index through the magnetic data measured by the Swarm three-satellite mission. From November 2014 to December 2019, we selected a balanced number of quiet and disturbed days, to get the most uniform set of Dst index values as possible. We then collected a big data collection of Swarm magnetic signals, confined to three very narrow belts of low-to-mid latitude: this choice allows it to better resemble the geographic distribution of the geomagnetic observatories contributing to the calculation of Dst. We also extended the analysis to mid latitude locations to increase the number of satellite samples. Once we determined by means of simulations the best network topology, we trained the network and tested its capabilities. The outcomes show that the ANN is able to give a reliable fast estimation of the Dst index directly from Swarm satellite magnetic data.
    Description: Published
    Description: 837-855
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Publication Date: 2022-03-16
    Description: Based on the review of the available stratigraphic, tectonic, morphological, geodetic, and seismological data, along with new structural observations, we present a reappraisal of the potential seismogenic faults and fault systems in the inner northwest Apennines, Italy, which was the site, one century ago, of the devastating Mw ~6.5, 1920 Fivizzano earthquake. Our updated fault catalog provides the fault locations, as well as the description of their architecture, large-scale segmentation, cumulative displacements, evidence for recent to present activity, and long-term slip rates. Our work documents that a dense network of active faults, and thus potential earthquake fault sources, exists in the region. We discuss the seismogenic potential of these faults, and propose a general tectonic scenario that might account for their development.
    Description: Published
    Description: 139
    Description: 2T. Deformazione crostale attiva
    Description: 4T. Sismicità dell'Italia
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Publication Date: 2022-03-16
    Description: Volcano seismology, while its value for surveillance of an active volcano is undebatable, is a very demanding field when it comes to station deployment, maintenance, and finally interpreting the measurements. Most valuable in the past was the deployment of arrays of sensors to evaluate the properties of the entire wavefield in order to classify, locate, and estimate the dominant mechanism of the corresponding sources. While very beneficial, an array of seismographs is very hard to maintain in a permanent installation at an active volcano. With the advent of new instrumentation based on fiber optic technology such as Distributed Acoustic Sensing (DAS) with fiber optic cables as well as Fiber-Optic Gyroscopes (FOG) the measurement of deformation and rotation, i.e., the gradient of the wavefield is feasible. The advantage of the FOG instrumentation with respect to DAS lies in the portability and ease of deployment, which is very similar to standard deployments of traditional seismometers. During a field campaign in summer 2018 we were able to install three FOGs together with classical broadband seismometers in close proximity to the active vents of Stromboli volcano (Italy). We show that with this new six-degrees-of-freedom (6DOF) measurement we are able to analyze the wavefield composition, a property normally reserved for array(s) of seismic sensors. As a first result, we can support earlier array-derived findings that a large portion of the wavefield at Stromboli volcano is formed by SV- and SH- type waves. We also present first locations of these signals facilitating the polarization properties of the combined measurement of gyroscopes and seismometers. They emphasize the benefit of recording wavefield gradients. In addition to these array-like results, the 6DOF recordings show a clear separation of at least three distinct groups of volcanic events of which two are already known and one represents a jetting event that appears nearly invisible for classical seismometers. However, rotational motions - or more general - gradients of the wavefield experience severe distortions by local velocity fluctuations and topography significantly complicating the application of 6DOF techniques at activate volcanoes.
    Description: Published
    Description: 107499
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: JCR Journal
    Keywords: 6 DOF ; rotational seismology ; volcanoseismology ; Stromboli ; 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Publication Date: 2022-03-11
    Description: In this paper, we present two novel experimental setups specifically designed to perform in situ long-term monitoring of the aging behaviour of commercial plastic granules (HDPE, PP, PLA and PBAT). The results of the first six months of a three year monitoring campaign are presented. The two experimental setups consist of: (i) special cages positioned close to the sea floor at a depth of about 10 m, and (ii) a box containing sand exposed to atmospheric agents to simulate the surface of a beach. Starting from March 2020, plastic granules were put into the cages and plunged in sea water in two different locations in the sand boxes. Chemical spectroscopic and thermal analyses (GPC, SEM, FTIR-ATR, DSC, TGA) were performed on the granules before and after exposure to natural elements for six months, in order to identify the physical-chemical modifications occurring in marine environmental conditions (both in seawater and in sandy coastal conditions). Changes in colour, surface morphology, chemical composition, thermal properties and molecular weight, and the polydispersity of the materials, showed the different influences of the environmental conditions. Photooxidative reaction pathways were prevalent in the sandbox. Abrasive phenomena acted specially in the sea environment. PLA and PBAT did not show significant degradation after six months, making the possible reduction of marine pollution due to this process negligible
    Description: Published
    Description: 1111
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Keywords: multi-parametric platform ; bioplastics ; polymer degradation ; marine environment ; microplastics ; spectroscopy
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Publication Date: 2022-03-15
    Description: Single rainwater samples were collected in the city of Goma (~1,1 million inhabitants), eastern Democratic Republic of the Congo, from January to June 2013 to draw a baseline for rainwater chemical composition and quality as influenced by the permanent plume of Nyiragongo volcano. This was a better period for a baseline as the neighboring Nyamulagira volcano, only 15 km apart, had no important degassing from its central crater, and hence the recorded volcanic influence on the rainwater chemistry was solely from Nyiragongo's lava lake which has been active since May 2002. The baseline for the rainwater chemistry and quality is important for this highly populated region where rainwater is the unique potable water source for the inhabitants of many villages surrounding the volcanoes, and for some of the inhabitants of the city of Goma. Our results show that samples collected at the crater rim of Nyiragongo were more acidic with pH ranging from 3.70 to 3.82, while the majority of rainwater samples collected in downtown Goma city and to the northeastern zone of the volcano had pH close to 5.7; which represents the value for rainwater from unpolluted continental areas (Berner and Berner, 2012). However, the pH was as low as 3.93 to the west of Nyiragongo volcano because the volcanic plume is directed westward by the dominant local wind direction. The western part of the city of Goma as well as the small town of Sake and many villages (e.g. Rusayo, Mubambiro, Kingi, …) are located in this zone, and experience endemic fluorosis caused by high fluoride in the available water. The mean F- in this zone was 0.38 mg/L, while the southern and northeastern zones had mean F- concentrations on 0.44 and 0.01 mg/L respectively; even though concentrations higher than the WHO guidelines were found in few samples from the western zone (1.69 mg/L) and from the southern zone (3.44 mg/L). Compared to data from Cuoco et al. (2012) obtained during the Nyamulagira 2010 eruption, and from Balagizi et al.2017 and Liotta et al., 2017 obtained during the intense degassing of both Nyiragongo and Nyamulagira lava lakes; we have noted similarity in the spatial variation of the pH, but samples from the present study showed notable lower concentrations of major elements. This is the case for fluoride which is strictly of volcanic origin. For the other major elements, anthropogenic sources, mainly the traffic and wind-blown dust; or other non-volcanic natural sources influenced their concentrations. Thus, the anions (Cl- and SO42-) and cations (Na+, K+, Mg2+, and Ca2+) from the present study are either lower compared to that previously reported in the literature for the Virunga, or are both comparable for the zones impacted by anthropogenic activities.
    Description: Published
    Description: 130859
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Endemic dental fluorosis; Nyamulagira volcano; Nyiragongo volcanic plume; Rainwater chemistry; Rainwater quality baseline
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Publication Date: 2022-03-15
    Description: The origin of magmatic fluids along the East African Rift System (EARS) is a long-lived field of debate in the scientific community. Here, we investigate the chemical composition of the volcanic gas plume and fumaroles at Nyiragongo and Nyamulagira (Democratic Republic of Congo), the only two currently erupting volcanoes set on the Western Branch of the rift. Our results are in line with earlier conceptual models proposing that volcanic gas emissions along the EARS mainly reflect variable contributions of either a Sub-Continental Lithospheric Mantle (SCLM) component or a Depleted Morb Mantle (DMM) component, and deeper fluid. At Nyiragongo and Nyamulagira, our study discards a major contribution of a high 3He/4He mantle plume component in the genesis of volcanic fluids beneath the area. High CO2/3He in fumaroles of both volcanoes is thought to reflect carbonate metasomatism in the lithospheric mantle source. As inferred by previous results obtained on the lava chemistry, this carbonate metasomatism would be more pronounced beneath Nyiragongo. This supports the idea of the presence of distinct metasomes within the lithospheric mantle beneath the Western Branch of the rift.
    Description: Published
    Description: 120811
    Description: 1V. Storia eruttiva
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: East African Rift System ; Volcano ; Gas chemistry ; 04.08. Volcanology ; 04.01. Earth Interior
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Publication Date: 2022-03-17
    Description: Coccolithophores were collected at 21 stations during summer 2016, from coastal and offshore areas of the Central Mediterranean Sea, to describe the ecology of the coccolithophore community integrating information on their abundance, environmental parameters (salinity, temperature, dissolved oxygen, and fluorescence) and oceanographic data. Emiliania huxleyi dominated the assemblage from surface to intermediate layers, while Florisphaera profunda was more abundant in the deep photic zone. Principal Component Analysis revealed that the distribution of coccolithophore taxa was influenced by environmental parameters: K-strategist taxa were related to warm surface waters, whereas lower photic zone taxa were influenced by the development of a Deep Chlorophyll Maximum and high salinity values, well below the thermocline. These results confirmed that a vertical species zonation, as a typical feature of low-middle latitude, characterizes the Central Mediterranean during summer. The distribution of F. profunda once again confirmed its use as a proxy of Deep Chlorophyll Maximum development and paleoproductivity estimates. Gephyrocapsa spp. (=total Gephyrocapsa), and in particular G. oceanica, were more abundant along the Atlantic Water pathway. Finally, the high concentration value of Helicosphaera carteri, recorded in the Ligurian Sea at an offshore station, suggested an expansion of the opportunist nature of this taxon from coastal environments to the offshore areas characterized by high turbidity and high productivity.
    Description: Published
    Description: 101995
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Keywords: Living coccolithophores ; Helicosphaera carteri ; Oceanography ; Ecology ; Central Mediterranean Sea ; coccolithophore ecology and oceanography
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2022-03-17
    Description: A high resolution study of calcareous nannofossils has been performed on samples from the Sapropel S1interval deposited in the North Ionian Sea, with the aim to assess the paleoenvironmental changes in the photic zone during this crucial interval in Mediterranean circulation. Calcareous nannofossil data have been integrated with planktonic foraminiferal data recently published from which the paleoclimatic curve has been constructed. Placoliths (namely Emiliania huxleyi) and Florisphaera profunda distributions, along with that of planktonic foraminifer Globigerinoides ruber white, evidence that, after a progressive weakening of surface water mixing, a deep chlorophyll maximum developed just prior to the sapropel deposition. We suggest that these changes took place as a response to enhanced precipitation conditions and riverine discharge as testified by increasing trend of reworked coccoliths and the occurrence of lower salinity taxon Braarudosphaera bigelowii. Calcareous nannofossils also point out that the oceanographic (water column stratification, reduced bottom water ventilation) and biogeochemical (increased primary production) processes that occurred during the S1 formation were particularly dominant during the earliest part of the older S1 warm phase (S1a). Our results support than some reventilation events of the shallow depth of studied site (665 m) occurred to some extent, particularly during the final phases of S1a. The distribution of holococcoliths, more abundant during the cold interruption phase S1i, seems confirm that the preservation of these tiny and delicate coccoliths, highly susceptible to dissolution, is enhanced under seafloor re-ventilation conditions. Finally, we tentatively suggest that preservation also plays a significant role in the distribution of the warm upper photic zone taxa, particularly during the warm S1b interval.
    Description: Published
    Description: 103599
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Keywords: Sapropel S1 ; Calcareous nannofossils ; Planktonic foraminifera ; North Ionian Sea ; Mediterranean ; Hydrosphere
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Publication Date: 2022-03-17
    Description: The understanding of fault-slip behaviour in carbonates has an important societal impact due to the widespread occurrence and propagation of earthquakes in these rocks. Fault rock variations in carbonates are systematically controlled by the lithology of the faulted protolith: cataclasis and hydraulic fracturing with evidence of past seismic slip commonly affect fault rocks in competent limestone formations whereas widespread pressure-solution and sliding along clay foliation are observed in marly rocks. We performed a series of friction experiments on carbonatic fault rocks sampled from mature thrusts (〉2km displacement) in the Apennines of Italy. We sheared both intact wafers and powdered fault materials at low (10MPa) and in situ(53MPa) normal stress under room-humidity and water-saturated conditions. We used velocity steps (1 to 300μm/s) and slide–hold–slide (3–1000 s holds) to assess the frictional stability and healing behaviour of these rocks. We observe that cataclastic fault rocks derived from competent limestones are characterized by high friction coefficients coupled with significant post-slip restrengthening and velocity-weakening behaviour. Conversely, intact foliated marly tectonites, sheared under the same conditions, show low friction, null post-slip healing and stable velocity-strengthening behaviour suggesting that these rocks deform aseismically. To extrapolate these opposite mechanical behaviours to the entire fault surface we developed a fault model integrating our mechanical data, field observations and balanced geological cross-sections. The mechanical heterogeneities highlighted in the model provide constraints for the distribution of fault patches with higher seismogenic potential.
    Description: Published
    Description: 307–318
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: JCR Journal
    Keywords: friction carbonates earthquakes fault
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Publication Date: 2022-03-18
    Description: Wetlands are hotspots of CH4 emissions to the atmosphere, mainly sustained by microbial decomposition of organic matter in anoxic sediments. Several knowledge gaps exist on how environmental drivers shape CH4 emissions from these ecosystems, posing challenges in upscaling efforts to estimate global emissions from waterbodies. In this work, CH4 and CO2 diffusive fluxes, along with chemical and isotopic composition of dissolved ionic and gaseous species, were determined from two wetlands of Tuscany (Italy): (i) Porta Lake, a small wetland largely invaded by Phragmites australis reeds experiencing reed die‐back syndrome, and (ii) Massaciuccoli Lake, a wide marsh area including open‐water basins and channels affected by seawater intrusion and eutrophication. Both wetlands were recognized as net sources of CH4 to the atmosphere. Our data show that the magnitude of CH4 diffusive emission was controlled by CH4 production and consumption rates, being mostly governed by (i) water temperature and availability of labile carbon substrates and (ii) water column depth, wind exposure and dissolved O2 contents, respectively. This evidence suggests that the highest CH4 diffusive fluxes were sustained by reed beds, providing a large availability of organic matter supporting acetoclastic methanogenesis, with relevant implications for global carbon budget and future climate models.
    Description: Published
    Description: 12156
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Publication Date: 2022-03-23
    Description: Mediterranean wetlands are severely affected by habitat degradation and related loss of biodiversity. In this scenario, the wide number of artificial farm ponds can play a significant role in the biodiversity conservation of aquatic flora. In the present contribution we show the preliminary results of a study on Mediterranean farm ponds of north-western Sicily (Italy), aimed to investigating the environmental factors linked to the occurrence of submerged macrophytes (vascular plants and charophytes). We studied the aquatic flora of 30 ponds and determined the chemical and isotopic composition of their water bodies on a subset of the most representative 10 sites. Results show that (1) farm ponds host few but interesting species, such as Potamogeton pusillus considered threatened at regional level; (2) Chara vulgaris, C. globularis and P. pusillus behave as disturbance-tolerant species, occurring both in nitrates-poor and nitrates-rich waters, whereas Stuckenia pectinata and Zannichellia palustris occur only in nitrates-poor waters. Although farm ponds are artificial and relatively poor habitats, these environments seem to be important for the aquatic flora and for the conservation of the local biodiversity, and can give useful information for the use of macrophytes as bioindicators in the Mediterranean area.
    Description: Published
    Description: 1292
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Mediterranean flora; aquatic flora; bioindicators; carbon isotopes; conservation; hydrophytes; inland waters; water geochemistry
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Publication Date: 2022-03-23
    Description: The Campi Flegrei geothermal system sets in one of the most famous and hazardous volcanic caldera in the world. The geothermal dynamics is suspected to have a crucial role in the monitored unrest phases and in the eruption triggering as well. Numerical models in the literature do not properly consider the geochemical effects of fluid-rock interaction into the hydrothermal circulation and this gap limits the wholly understanding of the dynamics. This paper focuses on fluid-rock interaction effects at the Campi Flegrei and presents relevant information requested for reactive transport simulations. In particular, we provide: (1) an extensive review of available data and new petrographic analyses of the San Vito cores rearranged in a conceptual model useful to define representative geochemical and petrophysical parameters of rock formations suitable for numerical simulations and (2) the implemented thermodynamic and kinetic data set calibrated for the San Vito 1 well area, central in the geothermal reservoir. A preliminary 0D-geochemical model, performed with a different contribution of CO2 at high (165 ◦C) and low (85 ◦C) temperatures, firstly allows reproducing the hydrothermal reactions over time of the Campanian Ignimbrite formation, the most important deposits in the case study area.
    Description: Published
    Description: 810
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 1TR. Georisorse
    Description: 4IT. Banche dati
    Description: JCR Journal
    Keywords: geothermal system ; hydrothermal alteration ; Campi Flegrei ; San Vito 1 well ; reactive model
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Publication Date: 2022-03-24
    Description: The ionospheric plasma density irregularities are known to play a role in the propagation of electromagnetic signals and to be one of the most important sources of disturbance for the Global Navigation Satellite System, being responsible for degradation and, sometimes, interruptions of the signals received by the system. In the equatorial ionospheric F region, these plasma density irregularities, known as plasma bubbles, find the suitable conditions for their development during post-sunset hours. In recent years, important features of plasma bubbles such as their dependence on latitude, longitude, and solar and geomagnetic activities have been inferred indirectly using their magnetic signatures. Here, we study the scaling properties of both the electron density and the magnetic field inside the plasma bubbles using measurements on board the Swarm A satellite from 1 April 2014 to 31 January 2016. We show that the spectral features of plasma irregularities cannot be directly inferred from their magnetic signatures. A relation more complex than the linear one is necessary to properly describe the role played by the evolution of plasma bubbles with local time and by the development of turbulent phenomena.
    Description: Published
    Description: 918
    Description: 2A. Fisica dell'alta atmosfera
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Publication Date: 2022-03-29
    Repository Name: EPIC Alfred Wegener Institut
    Type: Inbook , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Publication Date: 2022-03-21
    Description: Changbaishan, an intraplate volcano, is characterized by an approximately 6 km wide summit caldera and last erupted in 1903. Changbaishan experienced a period of unrest between 2002 and 2006. The activity developed in three main stages, including shield volcano (basalts), cone-construction (trachyandesites to trachytes with minor basalts), and caldera-forming stages (trachytes to comendites). This last stage is associated with one of the more energetic eruptions of the last millennium on Earth, the 946 CE, VEI 7 Millennium Eruption (ME), which emitted over 100 km3 of pyroclastics. Compared to other active calderas, the plumbing system of Changbaishan and its evolution mechanisms remain poorly constrained. Here, we merge new whole-rock, glass, mineral, isotopic, and geobarometry data with geophysical data and present a model of the plumbing system. The results show that the volcano is characterized by at least three main magma reservoirs at different depths: a basaltic reservoir at the Moho/lower crust depth, an intermediate reservoir at 10–15 km depth, and a shallower reservoir at 0.5–3 km depth. The shallower reservoir was involved in the ME eruption, which was triggered by a fresh trachytic melt entering a shallower reservoir where a comenditic magma was stored. The trachytes and comendites originate from fractional crystallization processes and minor assimilation of upper crust material, while the less evolved melts assimilate lower crust material. Syn-eruptive magma mingling occurred during the ME eruption phase. The magma reservoirs of the caldera-forming stage partly reactivate those of the cone-construction stage. The depth of the magma storage zones is controlled by the layering of the crust. The plumbing system of Changbaishan is vertically extensive, with crystal mush reservoirs renewed by the replenishment of new trachytic to trachyandesitic magma from depth. Unlike other volcanoes, evidence of a basaltic recharge is lacking. The interpretation of the signals preceding possible future eruptions should consider the multi-level nature of the Changbaishan plumbing system. A new arrival of magma may destabilize a part of or the entire system, thus triggering eruptions of different sizes and styles. The reference model proposed here for Changbaishan represents a prerequisite to properly understand periods of unrest to potentially anticipate future volcanic eruptions and to identify the mechanisms controlling the evolution of the crust below volcanoes.
    Description: National Natural Science Foundation of China (Grant Nos. 41972313 and 41790453), Engineering Research Center of Geothermal Resources Development Technology and Equipment, Ministry of Education, Jilin University, China, INGV Ricerca Libera.
    Description: Published
    Description: 101171
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: JCR Journal
    Keywords: 04.08. Volcanology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Publication Date: 2022-03-21
    Description: The presence of weak phyllosilicates in mature carbonate fault zones has been invoked to explain weak faults. However, the relation between frictional strength, fault stability, mineralogical composition, and fabric of fault gouge, composed of strong and weak minerals, is poorly constrained. We used a biaxial apparatus to systematically shear different mixtures of shale (68% clay, 23% quartz and 4% plagioclase) and calcite, as powdered gouge, at room temperature, under constant normal stresses of 30, 50, 100 MPa and under room-dry and pore fluid-saturated conditions, i.e. CaCO3-equilibrated water. We performed 30 friction experiments during which velocity-stepping and slide-hold-slide tests were employed to assess frictional stability and to measure frictional healing, respectively. Our frictional data indicate that the mineralogical composition of fault gouges significantly affects frictional strength, stability, and healing as well as the presence of CaCO3-equilibrated water. Under room-dry condition, the increasing shale content determines a reduction in frictional strength, from μ = 0.71 to μ = 0.43, a lowering of the healing rates and a transition from velocity-weakening to velocity-strengthening behavior. Under wet condition, with increasing shale content we observe a more significant reduction in frictional strength (μ = 0.65–0.37), a near-zero healing and a velocity strengthening behavior. Microstructural investigations evidence a transition from localized deformation promoted by grain size reduction, in calcite-rich samples, to a more distributed deformation with frictional sliding along clay-enriched shear planes in samples with shale content greater than 50%. For faults cutting across sedimentary sequences composed of carbonates and clay-rich sediments, our results suggest that clay concentration and its ability to form foliated and interconnected networks promotes important heterogeneities in fault strength and slip behavior.
    Description: Published
    Description: 228811
    Description: 1T. Struttura della Terra
    Description: JCR Journal
    Keywords: Carbonate faults ; Fault slip behavior ; 04.02. Exploration geophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Publication Date: 2022-03-21
    Description: The 2016 Central Italy earthquake sequence is characterized by remarkable rupture complexity, including highly heterogeneous slip across multiple faults in an extensional tectonic regime. The dense coverage and high quality of geodetic and seismic data allow us to image intriguing details of the rupture kinematics of the largest earthquake of the sequence, the Mw 6.5 October 30th, 2016 Norcia earthquake, such as an energetically weak nucleation phase. Several kinematic models suggest multiple fault planes rupturing simultaneously, however, the mechanical viability of such models is not guaranteed. Using 3D dynamic rupture and seismic wave propagation simulations accounting for two fault planes, we constrain “families” of spontaneous dynamic models informed by a high-resolution kinematic rupture model of the earthquake. These families differ in their parameterization of initial heterogeneous shear stress and strength in the framework of linear slip weakening friction. First, we dynamically validate the kinematically inferred two-fault geometry and rake inferences with models based on only depth-dependent stress and constant friction coefficients. Then, more complex models with spatially heterogeneous dynamic parameters allow us to retrieve slip distributions similar to the target kinematic model and yield good agreement with seismic and geodetic observations. We discuss the consistency of the assumed constant or heterogeneous static and dynamic friction coefficients with mechanical properties of rocks at 3-10 km depth characterizing the Italian Central Apennines and their local geological and lithological implications. We suggest that suites of well-fitting dynamic rupture models belonging to the same family generally exist and can be derived by exploiting the trade-offs between dynamic parameters. Our approach will be applicable to validate the viability of kinematic models and classify spontaneous dynamic rupture scenarios that match seismic and geodetic observations as well as geological constraints.
    Description: T.U., T., D.L., and A.-A. Gabriel are supported by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (TEAR, agreement No. 852992 and ChEESE, grant no. 823844), the German Research Foundation (DFG project grants no. GA 2465/2-1 and GA 2465/3-1) and by KAUST-CRG (grant no. ORS-2017-CRG6 3389.02). E.T. was supported by Progetti di Ricerca Sapienza (RM120172A2EAC019). Computing resources were provided by the Leibniz Supercomputing Centre (LRZ, project no. pr63qo on SuperMUC-NG).
    Description: Published
    Description: 117237
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: JCR Journal
    Keywords: earthquake source ; dynamic rupture ; high-performance computing ; frictional heterogeneity ; 04.06. Seismology ; 05.05. Mathematical geophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Publication Date: 2022-03-22
    Description: A systematic multiparametric and multiplatform approach to detect and study geo-space perturbations attributed to preparation processes related to natural hazards is fundamental in order to obtain useful insights on a series of complex dynamic phenomena of the Earth system, namely, earthquakes, volcanic and Saharan dust events, as well as geomagnetic disturbances. In particular, integrated analysis and interpretation of data from ground-based and spaceborne observations of the lower and upper atmospheres are of paramount importance for understanding the associated physical processes. In this Special Issue, we include pertinent studies on this field of research, presenting recent results and highlighting future directions for advances in the topic.
    Description: Published
    Description: 496
    Description: 7T. Variazioni delle caratteristiche crostali e "precursori"
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Publication Date: 2022-03-22
    Description: Crustal seismicity is in general confined within the seismogenic layer, which is bounded at depth by processes related to the brittle-ductile transition (BDT) and in the shallow region by fault zone consolidation state and mineralogy. In the past 10-15 years, high resolution seismological and geodetic data have shown that faulting within and around the traditional seismogenic zone occurs in a large variety of slip modes. Frictional and structural heterogeneities have been invoked to explain such differences in fault slip mode and behaviour. However, an integrated and comprehensive picture remains extremely challenging because of difficulties to properly characterize fault rocks at seismogenic depths. Thus, the central-northern Apennines provide a unique opportunity because of the integration of deep-borehole stratigraphy and seismic reflection profiles with high resolution seismological data and outcrop studies. These works show that seismic sequences are limited within the sedimentary cover (depth 〈 9-10 km), suggesting that the underlaying basement plays a key-role in dictating the lower boundary of the seismogenic zone. Here we integrate structural data on exhumed outcrops of basement rocks with laboratory friction data to shed light on the mechanics of the Apenninic basement. Structural data highlight heterogeneous and pervasive deformation where foliated and phyllosilicate-rich rocks surround more competent quartz-rich lenses up to hundreds of meters in thickness. Phyllosilicate horizons deform predominantly by folding and foliation-parallel frictional sliding whereas quartz-rich lenses are characterized by brittle signatures represented by extensive fracturing and minor faulting. Laboratory experiments revealed that quartz-rich lithologies have relatively high friction, μ ≈ 0.51, velocity-strengthening to neutral behaviour, and elevated healing rates. On the contrary, phyllosilicate-rich (muscovite and chlorite) lithologies show low friction, 0.23 〈 μ 〈 0.31, a marked velocity strengthening behaviour that increases with increasing sliding velocity and negligible rates of frictional healing. Our integrated approach suggests that in the Apenninic basement deformation occurs along shear zones distributed on thickness up-to several kilometres, where the frictionally stable, foliated, and phyllosilicate-rich horizons favour aseismic deformation and therefore confine the depth of major earthquake ruptures and the seismogenic zone.
    Description: Published
    Description: 117444
    Description: 2T. Deformazione crostale attiva
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    Publication Date: 2022-03-22
    Description: Low Earth orbit satellites collect and study information on changes in the ionosphere, which contributes to the identification of earthquake precursors. Swarm, the European Space Agency three-satellite mission, has been launched to monitor the Earth geomagnetic field, and has successfully shown that in some cases it is able to observe many several ionospheric perturbations that occurred as a result of large earthquake activity. This paper proposes the SafeNet deep learning framework for detecting pre-earthquake ionospheric perturbations. We trained the proposed model using 9017 recent (2014–2020) independent earthquakes of magnitude 4.8 or greater, as well as the corresponding 7-year plasma and magnetic field data from the Swarm A satellite, and excellent performance has been achieved. In addition, the influence of different model inputs and spatial window sizes, earthquake magnitudes, and daytime or nighttime was explored. The results showed that for electromagnetic pre-earthquake data collected within a circular region of the epicenter and with a Dobrovolsky-defined radius and input window size of 70 consecutive data points, nighttime data provided the highest performance in discriminating pre-earthquake perturbations, yielding an F1 score of 0.846 and a Matthews correlation coefficient of 0.717. Moreover, SafeNet performed well in identifying pre-seismic ionospheric anomalies with increasing earthquake magnitude and unbalanced datasets. Hypotheses on the physical causes of earthquake-induced ionospheric perturbations are also provided. Our results suggest that the performance of pre-earthquake ionospheric perturbation identification can be significantly improved by utilizing SafeNet, which is capable of detecting precursor effects within electromagnetic satellite data.
    Description: Published
    Description: 5033
    Description: 7T. Variazioni delle caratteristiche crostali e "precursori"
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Publication Date: 2022-03-25
    Description: Available manually scaled foF2 observations over 50 years on Juliusruh, 33 years on Slough, and 37 years on Rome stations were used to check the association between quiet-time foF2 disturbances (Q-disturbances) and following on isolated magnetic storms. Of course, such cases exist, however Pearson's contingency coefficient, Chi-square and Odds ratio tests applied to check a measure of association gave the absence of relationship even at the 95% confidence level. The lack of association makes it impossible to use F2-layer disturbances as precursors for magnetic storms. The observed cases of apparent relationship between two events should be considered as random and physically unconditioned. The published cases indicating the relationship between two events can be explained in the framework of regular F2-layer variations not related by any means to the following on magnetic storms.
    Description: Published
    Description: 105473
    Description: 2A. Fisica dell'alta atmosfera
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Publication Date: 2022-03-25
    Description: On-fault processes during earthquakes contribute to seismic rupture propagation and slip. Here we investigate clast fragmentation in an experimental pseudotachylyte (solidified seismic melt) produced with a rotary shear machine. We slid for 0.44 m (corresponding to Mw ≥ 6 earthquakes), at slip rates 〉 1 m/s, pre-cut samples of quartz + phyllosilicates + plagioclase + sillimanite + garnet -bearing ultramylonite, that hosts pseudotachylytes in nature. The ultramylonite minerals extensively preserved as clasts in the experimental pseudotachylyte are quartz, plagioclase, and sillimanite. Garnet is scarcely preserved, despite having a melting temperature similar to plagioclase, probably due to having low thermal shock resistance. This selective clast survival is identical to the one found in the natural pseudotachylytes. Based on these experimental observations and assuming non-equilibrium melting, the preservation of a mineral, as a clast, in the melt appears to be controlled by its thermal shock properties as well as by its melting temperature. Since the mechanical effects of rupture propagation in these experiments were negligible, we conclude that, for Mw ≥ 6 earthquakes, (i) frictional slip and heating of the slipping zone plus (ii) thermomechanical properties of minerals, rather than fault rupture processes, control mineral comminution and clast survival in frictional melts.
    Description: This work was supported by: University of Padova BIRD175145/17 (G.P.), European Research Council CoG project 614750 NOFEAR (G.D.T. and E.S.), and NSERC Discovery Grant 2018–06023 (A.Cam.). The authors thank Leonardo Tauro (University of Padova) for thin section preparation. The authors acknowledge two anonymous reviewers and the Editor Fabrizio Agosta for their constructive comments.
    Description: Published
    Description: 104328
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Publication Date: 2022-03-25
    Description: The magnitude and intensity of the 60 CE Cretaio Tephra, the largest historical explosive eruption at Ischia caldera (Italy), was studied integrating field data and numerical modelling in order to reconstruct the dispersal of the fall out related to the climax phase of the eruption and characterize its physical parameters. A field survey of the main fall unit (EUC) of Cretaio Tephra and its sampling was performed on the island, which is the proximal area of dispersal, and for the first time outcrops of this tephra were found southward on the Capri Island. The dataset is completed by a distal tephra sampled in the offshore and described in the literature, allowing the analysis of samples of intermediate and distal deposits. Grain size analysis of the samples collected on the island show bimodal distributions due to the presence of a ballistic component, especially in the most proximal sampling sites around the inferred and buried vent. Tails of fine ash in the distributions can be associ ated with settling enhanced by ash aggregation processes in the moisture-rich plume. Tephra dispersal was re constructed using the HAZMAP tephra dispersal model by minimizing the difference between the simulations obtained exploring plausible ranges of eruption source parameters and the available thickness and grain-size measurements. Results show that the dispersal axis of EUC is to the south-southeast, the best guess for the total erupted volume of tephra is 0.075 km3 , the plume height ranges between 5 and 13 km, for an average mass eruption rate (MER) of 105 kg/s, hence a duration of the eruption of a few days. Considering an eruptive sce nario given by the eruption parameters and diffusion coefficient of the Cretaio Tephra, together with a statistical set of wind profiles, HAZMAP modelling allowed us to generate tephra loading probability maps, needed to assess the impact of such an eruption at Ischia Island and the Neapolitan metropolitan area, pivotal for civil protection purposes. Another important outcome of the study is that, for volcanic islands, the reconstruction of eruption parameters may benefit much more from the search of even few medial and distal offshore outcrops than from implementing the on-island proximal dataset only.
    Description: Published
    Description: 107248
    Description: 5V. Processi eruttivi e post-eruttivi
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: JCR Journal
    Keywords: fallout features ; Cretaio Tephra (Ischia Island, Italy) ; data analysis ; numerical modelling: ; hazard assessment
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Publication Date: 2022-02-28
    Description: The polyphase structural evolution of a sector of the internal Central Apennines, where the significance of pelagic deposits atop neritic carbonate platform and active margin sediments has been long debated, is here documented. The results of a new geological survey in the Volsci Range, supported by new stratigraphic constraints from the syn-orogenic deposits, are integrated with the analysis of 2D seismic reflection lines and available wells in the adjacent Latin Valley. Late Cretaceous syn-sedimentary faults are documented and interpreted as steps linking a carbonate platform to the adjacent pelagic basin, located to the west. During Tortonian time, the pelagic deposits were squeezed off and juxtaposed as mélange units on top of the carbonate platform. Subsurface data highlighted stacked thrust sheets that were first involved into an initial in-sequence propagation with top-to-the-ENE, synchronous to late Tortonian foredeep to wedge-top sedimentation. We distinguish up to four groups of thrust faults that occurred during in-sequence shortening (thrusts 1–3; about 55–60 km) and backthrusting (thrust 4). During Pliocene to recent times, the area has been uplifted and subsequently extended by normal faults cross-cutting the accretionary wedge. Beside regional interest, our findings bear implications on the kinematic evolution of an orogenic wedge affected by far-traveled units.
    Description: Published
    Description: 160
    Description: 4T. Sismicità dell'Italia
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Publication Date: 2022-02-28
    Description: Leucititic rocks, K-foiditic in composition are volumetrically important in the Colli Albani (also known as Alban Hills) volcanic district (Central Italy) especially during the most explosive phases of activity (〉200 km3). The Colli Albani tephra in distal (〉500 km) deposits indicates that K-foiditic magma chambers fed large explosive eruptions (i.e., tens of km3 of pyroclastic rocks). Major oxides, trace elements and Raman spectra were measured on the glasses and minerals occurring in the K-foiditic scoria clasts of the ~530 kyr-old Tufo del Palatino, erupted in the Colli Albani volcanic district. The Colli Albani pre-eruptive magmatic system is characterized by the aH2O 〈 1 and high CO2 activ- ity in the melt, as testified by the CO3 in the clinopyroxene melt inclusions, by the early crystallization of CO3-bearing apatite and by the high CO2 activity in the free volatile phase that led to crystallization of calcium carbonate in the scoria clast vesicles. The K-foiditic magmas plot on the Cpx + Lc + melt divariant surface of the Ol-Cpx-Lc-Mel- H2O-CO2, P ≥ 0.2 GPa and T ≤ 1100 °C. The assimilation of cold carbonate by hot magmas is an important open- system process allowing the establishment of aH20 〈 1 condition in the volatile-rich, Colli Albani magma chambers where the stability fields of the olivine and phlogopite are reduced in favor of clinopyroxene and leucite. Trace ele- ment modelling indicates large amount of carbonate assimilation (~12.4 wt%) involved in the differentiation process that origins the K-foiditic magmas starting from a K-rich, phonotephritic parental magma. The large amount of as- similate carbonate is consistent with the peculiar distribution of the latent heat across the crystallization interval of the phonotephritic parental magma. The isenthalpic assimilation process is very efficient in the phonotephritic magma because the crystallization of clinopyroxene and leucite in equilibrium with a K-foiditic melt proceeds over a relatively large temperature interval (〉200 °C) and the K-foiditic melt shows low viscosity (104Pa·s at 1000 °C). Actually, the low melt viscosity, that increases the growth rate, and the large temperature interval of crys- tallization are intrinsic factors that increase the release of the latent heat of crystallization from the phonotephritic parental magma. Extrinsic factors enhancing the assimilation process efficiency are the thickness (〉4 km) and the depth (down to 5–7 km) of the carbonate substrate in the Colli Albani volcanic district.
    Description: Published
    Description: 106239
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Publication Date: 2022-02-28
    Description: A crystal chemical investigation of a natural specimen of whitlockite, ideally Ca9Mg(PO4)6[PO3(OH)], from Palermo Mine (USA), was achieved by means of a combination of electron microprobe analysis (EMPA) in WDS mode, single‐crystal neutron diffraction probe (NDP) and single‐crystal X‐ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. The crystal‐chemical characterization resulted in the empirical formula (Ca8.682Na0.274Sr0.045)Σ9.000(Ca0.034□0.996)Σ1.000(Mg0.533Fe2+0.342Mn2+0.062Al0.046)Σ0.983(P1.006O4)6[PO3(OH0.968F0.032)Σ1.000]. Crystal‐structure refinement, in the space group R3c, converged to R1 = 7.12% using 3273 unique reflections from NDP data and to R1 = 2.43% using 2687 unique reflections from XRD data. Unit cell parameters from NDP are a = 10.357(3) Å, c = 37.095(15) Å and V = 3446(2) Å3, and from XRD, the parameters are a = 10.3685(4) Å, c = 37.1444(13) Å and V = 3458.2(3) Å3. NDP results allowed a deeper definition of the hydrogen‐bond system and its relation with the structural unit [PO3(OH)]. The FTIR spectrum is very similar to that of synthetic tricalcium phosphate Ca3(PO4)2 and displays minor band shifts due to slightly different P‐O bond lengths and to the presence of additional elements in the structure. A comparison between whitlockite, isotypic phases from the largest merrillite group, and its synthetic counterpart Ca3(PO4)2 is provided, based on the XRD/NDP and FTIR results.
    Description: Published
    Description: 225
    Description: 1TR. Georisorse
    Description: JCR Journal
    Keywords: whitlockite ; calcium phosphates ; Mineralogy ; crystal chemistry ; spectroscopy
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Publication Date: 2022-02-28
    Description: Seismic prediction was considered impossible, however, there are no reasons in theoretical physics that explicitly prevent this possibility. Therefore, it is quite likely that prediction is made stubbornly complicated by practical difficulties such as the quality of catalogs and data analysis. Earthquakes are sometimes forewarned by precursors, and other times they come unexpectedly; moreover, since no unique mechanism for nucleation was proven to exist, it is unlikely that single classical precursors (e.g., increasing seismicity, geochemical anomalies, geoelectric potentials) may ever be effective in predicting impending earthquakes. For this reason, understanding the physics driving the evolution of fault systems is a crucial task to fine-tune seismic prediction methods and for the mitigation of seismic risk. In this work, an innovative idea is inspected to establish the proximity to the critical breaking point. It is based on the mechanical response of faults to tidal perturbations, which is observed to change during the “seismic cycle”. This technique allows to identify different seismic patterns marking the fingerprints of progressive crustal weakening. Destabilization seems to arise from two different possible mechanisms compatible with the so called preslip patch, cascade models and with seismic quiescence. The first is featured by a decreasing susceptibility to stress perturbation, anomalous geodetic deformation, and seismic activity, while on the other hand, the second shows seismic quiescence and increasing responsiveness. The novelty of this article consists in highlighting not only the variations in responsiveness of faults to stress while reaching the critical point, but also how seismic occurrence changes over time as a function of instability. Temporal swings of correlation between tides and nucleated seismic energy reveal a complex mechanism for modulation of energy dissipation driven by stress variations, above all in the upper brittle crust. Some case studies taken from recent Greek seismicity are investigated.
    Description: Published
    Description: 9596
    Description: 2T. Deformazione crostale attiva
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Publication Date: 2022-02-28
    Description: New analyses of marine terraces in the Tyrrhenian Sea margin of Basilicata - northern Calabria (southern Italy) have been carried out. In the study area, c. 25 km in length, an impressive flight of marine terraces occurs, with the highest terraces reaching ~160 m a.s.l. Detailed geomorphological-stratigraphical analyses on remnants of paleoshorelines located within 60 m a.s.l. have shown that the rocky coast of the investigated coastal stretch has been affected by multiple relative sea-level fluctuations, during which reworking of older shorelines has occurred. Dating of the coral Cladocora caespitosa and speleothems, either predating or postdating single paleoshorelines, has allowed the construction of a chronological framework for the identified relative sea-level markers, and their correlation with MIS 7, MIS 6e and distinct peaks of MIS 5. A mean uplift rate of c. 0.25 mm/y since the Last Interglacial has been quantified, one order of magnitude larger than previous estimates. The uplift rate value has been used to infer the elevations of MIS 5a, 5c and 6e sea level peaks, which are higher than those reported in most sea level curves worldwide, although consistent with several findings from the western Mediterranean. Our results demonstrate that a mere sequential correlation may be misleading in the interpretation of flights of marine terraces and indicates that multiple age controls are crucial to unravelling the complex interaction between uplift and sea-level fluctuations in uplifted coastal areas. The reconstructed MIS 5a, 5c and 6e sea level paleo-elevations, besides contributing to the assessment of late Quaternary sea-level fluctuations in the Mediterranean Sea, may contribute to constrain coeval ice sheets volume variations.
    Description: Published
    Description: 107978
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Description: JCR Journal
    Keywords: Marine terraces ; morpho-stratigraphy ; Geochronological dating ; MIS 5 ; MIS 6e ; Tyrrhenian margin
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Publication Date: 2022-02-28
    Description: The behaviour of dry and wet volcanic granular flows is one of the main research topics in present day geophysics and volcanology. It involves various disciplines (e.g. sedimentology, geophysics, fluid dynamics) and investigation techniques (e.g. field studies, laboratory experiments, computational fluid dynamics). The vast interest is justified by the complex nature of these flows and their very dangerous nature that threaten millions of people around the world. In the last decade, computational fluid dynamics has become one of the main instruments used to reproduce past events of volcanic granular flows or to predict their behaviour and potential hazard. In this study, we tested two of the most used codes for simulating volcanic granular flows, TITAN2D and FLO2D, against well studied natural cases (the 1998 wet granular flows in the Sarno area and the 2005 block and ash flows at Colima volcano) and large-scale experiments on granular flows. Comparison between simulated parameters and real ones were carried out in order to evaluate strengths and weaknesses of the two numerical codes. TITAN2D results showed how the basal friction angle is fundamental to control numerical simulations and its dependence on the topographic complexities, DEM resolution and slope-angle ratio. Simulation of large scale experiments offered a good relationship between slope angle ratio at break in slope and basal friction angle, which is useful for application to small drainage basins with not complex channel morphology. FLO2D suffers the lack of rheometric parameters for volcaniclastic material, but is less sensitive of DEM resolution with respect to TITAN2D.
    Description: Published
    Description: 107146
    Description: 5V. Processi eruttivi e post-eruttivi
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Publication Date: 2022-02-28
    Description: Glacial-interglacial variations in ice volume and sea level are essential components of the Pleistocene global climate evolution. Deciphering the timing of change of these key climate parameters with respect to the insolation forcing is central to understanding the processes controlling glacial terminations. Here we exploit the sensitivity of the Paleo Tiber River (central Italy) to sea-level forced changes in the base level and the frequent occurrence of datable tephra layers in its sedimentary successions to reconstruct the timing of the relative sea-level (RSL) change between 450 and 403 ka, i.e., across the glacial termination (T-V) that marks the transition between Marine Isotope Stage (MIS) 12 and MIS 11. The analysis hinges on new stratigraphic data, tephra geochemical fingerprinting, and 40Ar/39Ar dating from a fluvial section that represents the inland counterpart of the near mouth, coastal aggradational succes- sions of the San Paolo Formation (SPF). Tephra correlation indicates that the morpho-stratigraphic record of the inland section is as sensitive to the sea-level change as its coastal counterparts, which makes it ideal to complement previous RSL reconstructions from the Tiber River catchment basin, thereby providing a more detailed picture of the sea-level history across T-V. Combined sedimentological and morphological proxies of the composed inland-coastal SPF record document the occurrence of two phases of relatively rapid sea-level rise, here interpreted as meltwater pulse (MWP) events. The earlier MWP occurred between ~450 and ~445 ka and matches a relatively minor episode of the sea-level rise documented in an existing RSL record, while the younger MWP at ~430 ka corresponds to the high amplitude sea-level rise that marks T-V. We find that both MWPs coincide with episodes of ice-rafted debris deposition in the North Atlantic (Heinrich-like events) and with attendant Southern Hemi- sphere warming, plausibly associated with the bipolar seesaw.
    Description: Published
    Description: 106976
    Description: 5A. Ricerche polari e paleoclima
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Publication Date: 2022-03-01
    Description: To examine the atmospheric responses to Arctic sea ice variability in the Northern Hemisphere cold season (from October to the following March), this study uses a coordinated set of large-ensemble experiments of nine atmospheric general circulation models (AGCMs) forced with observed daily varying sea ice, sea surface temperature, and radiative forcings prescribed during the 1979–2014 period, together with a parallel set of experiments where Arctic sea ice is substituted by its climatology. The simulations of the former set reproduce the near-surface temperature trends in reanalysis data, with similar amplitude, and their multimodel ensemble mean (MMEM) shows decreasing sea level pressure over much of the polar cap and Eurasia in boreal autumn. The MMEM difference between the two experiments allows isolating the effects of Arctic sea ice loss, which explain a large portion of the Arctic warming trends in the lower troposphere and drive a small but statistically significant weakening of the wintertime Arctic Oscillation. The observed interannual covariability between sea ice extent in the Barents–Kara Seas and lagged atmospheric circulation is distinguished from the effects of confounding factors based on multiple regression, and quantitatively compared to the covariability in MMEMs. The interannual sea ice decline followed by a negative North Atlantic Oscillation–like anomaly found in observations is also seen in the MMEM differences, with consistent spatial structure but much smaller amplitude. This result suggests that the sea ice impacts on trends and interannual atmospheric variability simulated by AGCMs could be underestimated, but caution is needed because internal atmospheric variability may have affected the observed relationship.
    Description: Published
    Description: 8419–8443
    Description: 2A. Fisica dell'alta atmosfera
    Description: JCR Journal
    Keywords: Arctic ; Sea ice ; Atmospheric circulation ; Climate models ; 01.01. Atmosphere
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Publication Date: 2021-12-01
    Description: Although several observations have been reported in the literature before a strong earthquake, their relation with the forthcoming event is often controversial. Since many physical processes and parameters govern the dynamics of preparation, initiation, and occurrence of earthquakes, their understanding is essential for explaining anomalous seismological, geophysical, hydrological and geodetic signals before a strong earthquake that may be considered for seismic monitoring and hazard assessment. In this work, the interseismic and coseismic stress and strain fields associated with the 6 April 2009, Mw 6.3 L’Aquila earthquake are calculated via a 3D numerical model designed to simulate the crustal interseismic loading and the coseismic brittle episodic dislocation along the fault. The model adopts a framework of gravitational and tectonic forces that are compatible with the geodynamics of the Central Apennines region of the Italian territory. The model assumes a brittle upper crust, where the fault has stick-slip behaviour, and a plastic deeper crust, where the fault is in stationary creep. The results indicate that the concurrent action of gravitational and tectonic forces determines steep inter- seismic stress gradients at the transition between the creeping and locked fault planes that promote the coseismic subsidence of the hanging wall. The interseismic strain above the transition between that locked upper fault and its unlocked lower shear zone develops a dilated volume in the hanging wall and a contracted volume in the footwall. These stress and strain variations are compatible with seismological, geophysical and geodetic anomalies observed before the earthquake, i.e., Vp/Vs anomalies and location of foreshocks. Interseismic stress and strain patterns invert during the coseismic stage. The dilated volume, formed during the interseismic phase, will be contracted at the coseismic stage and, conversely, the footwall volume previously contracted will be expanded.
    Description: Published
    Description: 228685
    Description: 2T. Deformazione crostale attiva
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Publication Date: 2021-12-22
    Description: Volcanic emissions are a well-known hazard that can have serious impacts on local populations and aviation operations. Whereas several remote sensing observations detect high-intensity explosive eruptions, few studies focus on low intensity and long-lasting volcanic emissions. In this work, we have managed to fully characterize those events by analyzing the volcanic plume produced on the last day of the 2018 Christmas eruption at Mt. Etna, in Italy. We combined data from a visible calibrated camera, a multi-wavelength elastic/Raman Lidar system, from SEVIRI (EUMETSAT-MSG) and MODIS (NASA-Terra/Aqua) satellites and, for the first time, data from an automatic sun-photometer of the aerosol robotic network (AERONET). Results show that the volcanic plume height, ranging between 4.5 and 6 km at the source, decreased by about 0.5 km after 25 km. Moreover, the volcanic plume was detectable by the satellites up to a distance of about 400 km and contained very fine particles with a mean e ective radius of about 7 m. In some time intervals, volcanic ash mass concentration values were around the aviation safety thresholds of 2 10􀀀3 g m􀀀3. Of note, Lidar observations show two main stratifications of about 0.25 km, which were not observed at the volcanic source. The presence of the double stratification could have important implications on satellite retrievals, which usually consider only one plume layer. This work gives new details on the main features of volcanic plumes produced during low intensity and long-lasting volcanic plume emissions.
    Description: Published
    Description: 3866
    Description: 5V. Processi eruttivi e post-eruttivi
    Description: JCR Journal
    Keywords: 04.08. Volcanology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    Publication Date: 2021-12-15
    Description: Study of a natural analogue for risk assessment. Experimental and numerical modelling approach was applied. Technique validation for measuring the flux of a CO2 single point emission site. We did an experimental and numerical modelling approach to prove methods and results.
    Description: Carbon dioxide is an essential gas for life on earth although it can be lethal to living beings at high concentrations in the atmosphere. Episodic release of CO2 from underground can occur either from natural processes (i.e., mantle degassing, thermal decarbonation) or industrial (geological storage of CO2, CCS). CO2 is a colourless and odourless gas denser than air, and once released in the atmosphere from point sources, its dynamics is initially governed by buoyancy and a gas cloud can accumulate above the ground (gravitational phase) leading to the formation of the so-called “CO2 lakes”. With time, CO2 distribution is then governed by wind and atmospheric turbulence (passive dispersion phase). Natural analogues provide evidences of the impact of CO2 leakage on vegetal cover, wild life and human beings. In this work, the dynamics of CO2 in the atmosphere after ground emission is assessed to quantify their potential risk. Two approaches have been followed: (1) direct measurement of air concentration in a natural emission site, where formation of a “CO2 lake” is common and (2) numerical atmospheric modelling with the TWODEE code. The studied site is located in the Campo de Calatrava region in central Spain, which is known for a widespread degassing of mantle-derived CO2. This site, called Cañada Real, has a degassing rate between 1 and 3 tonnes of CO2 per day. When atmospheric conditions are quite stable, i.e., negligible wind speed, the formation of a blanket of CO2-enriched air is visible at naked eye reaching up to 50 cm high. The CO2 concentration measured in air is typically higher than 10,000 ppm in most monitoring stations. The measured data are consistent with the numerical models that predict maximum concentration between 40,000 and 70,000 ppm CO2 in air, which is by far higher than the 30,000 ppm threshold from which hazardous effects on human beings are observed. Conclusions from this work, however, indicate that the risk for humans even at large emission rates is low due to the CO2 dispersion effect into the atmosphere, and only under very particular conditions lethal effects are predicted.
    Description: Published
    Description: 38-47
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Experimental and numerical modelling ; atmospheric dispersion ; Risk assessment ; Natural analogue ; Leakage ; Carbon storage ; carbon dioxide ; co2 field survey ; SOLID EARTH ; vulcanology ; geology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Publication Date: 2021-11-26
    Description: The volcanic activity that built up the Monte dei Porri stratocone (Salina Island) was reconstructed using new stratigraphic data, which allowed seven eruption units to be distinguished. Alternating Strombolian/Vulcanian to sub-Plinian/Plinian explosive and effusive activity emplaced fall and pyroclastic density current deposits and lava flows that formed the volcanic cone. The minimum erupted bulk volumes were assessed at 100 × 10 6 m 3 each for EU1, EU2, EU3 and EU6, while that of EU4 is ca. 200 × 10 6 m 3 . Rough estimation of EU7 volume yields values around 150 × 10 6 m 3 . The calculation of volume was not possible for the EU5 deposits. The magmas that fed the different eruption units of the Monte dei Porri succession range in composition from basalt to andesite, with the exception of dacites erupted in the initial phase of activity. SEM image analyses on coarse ash from the different pyroclastic units suggest that hydromagmatic fragmentation cannot be the cause of the large variations in explosivity observed throughout the stratigraphic succession. Based on the lithic component of pyroclastic deposits and xenolith contents of lava flows, the plumbing system that fed the different eruption units of Monte dei Porri was split into a deep magma storage level (15–20 km) and shallower magma batches (3–5 km). Our calculations indicate that the volumes of erupted material can account for magmatic triggering (injection of new magma) of eruptive units from the shallower feeding system, but they are not sufficient for suggesting magmatic initiation of the eruption units from the deeper feeding system. It is therefore assumed that the eruptions from the deep magma reservoir necessitate a favourable lithostatic stress, likely calling for a reduction of the local tectonic forces. A qualitative model explaining the eruptive style transitions among and within the different eruption units is presented, taking into account the relation between magmatic overpressure and lithostatic stress.
    Description: Published
    Description: 1-22
    Description: 5V. Processi eruttivi e post-eruttivi
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    facet.materialart.
    Unknown
    Elsevier
    Publication Date: 2022-02-10
    Description: The airborne magnetic method was established a few decades ago, as a strong tool in mining and petroleum exploration. Several economically relevant discoveries are often credited to aeromagnetism. Geological reconnaissance and mapping, deep crustal and upper mantle studies, environmental characterization, and national and international security issues can greatly benefit from the aeromagnetic method, as compared with other geophysical prospecting schemes. The rapid rate of coverage and the low cost per unit area explored represent just a few among the many advantages of the technique. Consequently, large-scale airborne magnetic surveys have been carried out in various parts of the globe. The amount of direct discoveries of ore bodies by means of aeromagnetism is impressive. Large magnetic iron deposits found in the early 1960s are in Southern California, Missouri, Nevada, Pennsylvania, Quebec, Ontario, and elsewhere. In the field of petroleum exploration, the method has also been used, although with less direct application. Depth to magnetic basement estimation in sedimentary basins narrows down areas of interest where to conduct exploration surveys in detail by means of more costly methods. The most relevant use of airborne magnetic results is crustal imaging and characterization. Nowadays, geology is interpreted in three dimensions using a digital aeromagnetic map.
    Description: Published
    Description: 675-688
    Description: 1T. Struttura della Terra
    Description: 4T. Sismicità dell'Italia
    Description: 6T. Studi di pericolosità sismica e da maremoto
    Description: 1V. Storia eruttiva
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare
    Description: 5A. Ricerche polari e paleoclima
    Description: 7A. Geofisica per il monitoraggio ambientale
    Description: 1TR. Georisorse
    Description: 2TR. Ricostruzione e modellazione della struttura crostale
    Description: 6SR VULCANI – Servizi e ricerca per la società
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Keywords: aeromagnetism ; potential fields ; magnetic anomaly ; 04.02. Exploration geophysics ; 04.05. Geomagnetism ; 04.07. Tectonophysics ; 04.08. Volcanology ; 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Publication Date: 2021-11-08
    Description: Over the last few years, several authors have presented contrasting models to describe the response of boulders to extreme waves, but the absence of direct observation of movements has hindered the evaluation of these models. The recent development of online video-sharing platforms in coastal settings has provided the opportunity to monitor the evolution of rocky coastlines during storm events. In September 2018, a surveillance camera of the Marine Protected Area of Plemmirio recorded the movement of several boulders along the coast of Maddalena Peninsula (Siracusa, Southeastern Sicily) during the landfall of the Mediterranean tropical-like cyclone (Medicane) Zorbas. Unmanned autonomous vehicle (UAV) photogrammetric and terrestrial laser scanner (TLS) surveys were performed to reconstruct immersive virtual scenarios to geometrically analyze the boulder displacements recorded in the video. Analyses highlighted that the displacements occurred when the boulders were submerged as a result of the impact of multiple small waves rather than due to a single large wave. Comparison between flow velocities obtained by videos and calculated through relationships showed a strong overestimation of the models, suggesting that values of flow density and lift coefficient used in literature are underestimated.
    Description: Published
    Description: 1497
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Publication Date: 2021-12-23
    Description: Thermal activity is a common precursor to explosive volcanic activity. The ability to use these thermal precursors to monitor the volcano and obtain early warning about upcoming activity is beneficial for both human safety and infrastructure security. By using a very reliably active volcano, Stromboli Volcano in Italy, a method has been developed and tested to look at changes in the frequency of small scale explosive activity and how this activity changes prior to larger, ash producing explosive events. Thermal camera footage was used to designate parameters for typical explosions at Stromboli (size of spatter field, cooling rate, frequency of explosions) and this information was applied to characterize explosions in satellite imagery. Satellite data from The National Aeronautics and Space Administration's Moderate Resolution Imaging Spectroradiometer (MODIS) and US/Japan designed Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) for numerous periods in 2002 to 2009 were analyzed for thermal features which were used to calculate an estimate of the level of activity during the given time period. The results at Stromboli showed a high level of small scale explosions which stop completely prior to large paroxysmal eruptive episodes. This activity also corresponds well to seismic and infrasonic records at Stromboli, indicating that this thermal infrared monitoring method may be used in conjunction with other detection methods where available, and also indicates that it may be a useful method for volcano monitoring when other methods (e.g. seismic instrumentation, infrasound arrays, etc.) are not available.
    Description: Published
    Description: 159-171
    Description: 5V. Processi eruttivi e post-eruttivi
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Publication Date: 2021-11-08
    Description: The dynamics of the sandy coast between Castellaneta and Taranto (Southern Italy) has been influenced by many natural and anthropogenic factors, resulting in significant changes in the coastal system over the last century. The interactions between vertical components of sea-level changes and horizontal components of the sedimentary budget, in combination with anthropogenic impact, have resulted in different erosion and accretion phases in the past years. Local isostatic, eustatic, and vertical tectonic movements, together with sedimentary budget changes, must be considered in order to predict the shoreline evolution and future marine submersion. In this study, all morpho-topographic data available for the Gulf of Taranto, in combination with Vertical Land Movements and sea-level rise trends, were considered by assessing the local evolution of the coastal trend as well as the future marine submersion. Based on the predicted spatial and temporal coastal changes, a new predictive model of submersion was developed to support coastal management in sea-level rise conditions over the next decades. After that, a multi-temporal mathematical model of coastal submersion was implemented in a Matlab environment. Finally, the effects of the relative sea-level rise on the coastal surface prone to submersion, according to the Intergovernmental Panel on Climate Change Assessment Reports (AR) 5 Representative Concentration Pathways (RCP) 2.6 and RCP 8.5 scenarios, were evaluated up to 2100.
    Description: Published
    Description: 1414
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Publication Date: 2022-02-11
    Description: The resuspension of volcanic ash by wind is a significant source of hazard during and after volcanic eruptions. Parameterizing and modeling ash resuspension requires direct measurement of the minimum wind shear stress required to move particles, usually expressed as the threshold friction velocity U*th, a parameter that, for volcanic ash, has been measured only scarcely and always in the laboratory. Here, we report the first field measurements of U*th for volcanic ash, with a portable wind tunnel specifically developed, calibrated, and tested. Field measurements, performed on natural reworked ash deposits from Sakurajima (Japan) and Cordón Caulle (Chile) volcanoes, agree well with our laboratory determinations on ash from the same deposits, with values of U*th ranging from 0.13 to 0.38 m/s. Our results show that the median grain size of the deposit and particle shape have a stronger control on U*th than the local substratum nature and deposit texture.
    Description: Published
    Description: 116684
    Description: 5V. Processi eruttivi e post-eruttivi
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: JCR Journal
    Keywords: wind resuspension ; wind tunnel ; detachment threshold ; volcanic ash ; Sakurajima volcano ; Cordon Caulle volcano ; 04.08. Volcanology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    Publication Date: 2021-11-25
    Description: This article describes research aimed at developing a system able to support local authorities and port communities in optimizing port navigation, avoiding or managing critical situations induced by sea-level variations in harbours and minimizing environmental damages and economic losses. In the Mediterranean basin, sea-level changes are mostly due to astronomical tides, related to the gravitational attraction between Earth, Moon and Sun. Nevertheless, sea-level variations are also influenced by meteorological tides, which are geodetic adjustments of sea surface due to atmospheric pressure variations above a water basin. So, starting from monitoring or forecasting environmental parameters in harbours, the system updates port bathymetric maps based on sea-level variations (acquired in the past, measured in real-time, or expected in the future) and detects hazardous areas for a certain ship moving inside a port at a given moment, by means of the implementation of “virtual traffic lights”. The system was tested on some real situations, including the analysis of maritime accidents (stranding of ships), providing satisfactory results by correctly signalling potentially dangerous areas variable over time. The architecture of the system and results achieved using it in the ports of Livorno and Bari, in Italy, are herewith described.
    Description: Published
    Description: 10265
    Description: 4A. Oceanografia e clima
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Publication Date: 2021-11-29
    Description: Sources of groundwater contaminants in inhabited areas, located in complex geo-tectonic contexts, are often deeply interlocked, thus, making the discrimination between anthropic and natural origins difficult. In this study, we investigate the Peloritani Mountain aquifers (Sicily, Italy), using the combination of probability plots with concentration contour maps to retrieve an overall view of the groundwater geo-chemistry with a special focus on the flux of heavy metals. In particular, we present a methodology for integrating spatial data with very different levels of precision, acquired before and during the “geomatic era”. Our results depict a complex geochemical layout driven by a geo-puzzle of rocks with very different lithological natures, hydraulically connected by a dense tectonic network that is also responsible for the mixing of deep hydrothermal fluids with the meteoric recharge. Moreover, a double source, geogenic or anthropogenic, was individuated for many chemicals delivered to groundwater bodies. The concentration contour maps, based on the different data groups identified by the probability plots, fit the coherency and congruency criteria with the distribution of both rock matrices and anthropogenic sources for chemicals, indicating the success of our geostatistical approach.
    Description: Published
    Description: 3269
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Publication Date: 2021-12-14
    Description: Fluids play an important role in seismic faulting both at hypocentral depths during earthquake nucleation and at shallower crustal levels during rupture propagation. Pre- to co-seismic anomalies of crustal fluid circulation have been identified by hydrogeochemical and seismological monitoring and interpreted as potential precursors of strong earthquakes. To shed light on the role of fluids in seismic and precursory mechanisms, the active carbonate-hosted principal slip zone (7-8 cm thick) of the exhumed (exhumation 〈 3 km) normal Mt. Morrone Fault (central Apennines) has been investigated with a multi-disciplinary approach from the macro- to the nano-scale. The distal slip zone consists of white cementitious calcite-rich bands and red cataclastic bands composed of dolomite and calcite clasts embedded in a clay-rich matrix. The proximal slip zone consists of subparallel ultracataclastic layers separated by sharp slip surfaces. The ultracataclastic layers mutually inject/overprint, bearing evidence of granular fluidization, dolomite thermal decomposition, and clay amorphization. Fluid inclusions and the distribution of both trace and major elements reveal the inflow of both shallow and deep external fluids into the slip zone. Presumably, the deep fluids originated from a magmatic-like source and ascended along the fault during pre-seismic dilation and seismic ruptures, interacting with shallow phyllosilicate-rich flysch deposits and the fluids hosted within them. In this context, vanadium-rich fluidized microlayers along the exhumed Mt. Morrone Fault are reminiscent of vanadium-rich potential hydrogeochemical precursors arose in the shallow aquifers of the study area since a few months before the 2016 Mw 6.0 Amatrice earthquake.
    Description: Published
    Description: 117010
    Description: 7T. Variazioni delle caratteristiche crostali e "precursori"
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Publication Date: 2021-12-15
    Description: In order to elucidate the kinetic partitioning of cations between olivine and basalt, we performed undercooling (−ΔT) and cooling rate (CR) experiments at atmospheric pressure and QFM-2 buffer. Starting from the superliquidus temperature of 1250 °C, a Hawaiian tholeiitic basalt was cooled at the rates of 4 (CR4), 20 (CR20), and 60 (CR60) °C/h to the final target temperatures of 1175 °C (−ΔT = 35 °C; −ΔT35) and 1125 °C (−ΔT = 85 °C; −ΔT85). Results show that polyhedral olivine morphologies are obtained at -ΔT35, whereas strong disequilibrium skeletal and/or dendritic textures form at -ΔT85. The amount of forsterite in olivine decreases from to 85% to 78% with increasing both -ΔT and CR. A diffusive boundary layer also develops in the melt next to the olivine surface and its composition becomes progressively enriched in Ca, owing to its incompatible behavior with the lattice site. Residual melts are progressively depleted in silica and enriched in alkali from CR4 to CR60, but silica-rich melts are observed with increasing -ΔT. In terms of Fe2+-Mg exchange, olivines obtained at -ΔT35 are always in equilibrium with the diffusive boundary layer, comprising both the interface melt next to the olivine surface and the far-field melt where all chemical gradients cease. At -ΔT85, however, the Fe2+-Mg exchange indicates two distinct equilibration stages between olivine core and far-field melt, and between olivine rim and interface melt. Partition coefficients (Kd) of Mg, Fe, Mn, Ca, and Cr calculated at the olivine-melt interface preferentially change as a function of -ΔT rather than CR. From -ΔT35 to -ΔT85, KdMg, KdFe, KdMn, and KdCr remarkably increase, whereas the opposite applies to KdCa. Through the application of equilibrium partitioning models, we found that Mg, Fe, Mn, and Ca are incorporated into the olivine lattice site at near-equilibrium proportions. This generally good agreement with modeling data demonstrates that diffusive mass transport of cations in our experiments occurred under the conditions of local equilibrium at the olivine surface. In contrast, marked deviations from the expected equilibrium are found for KCr in response to the major influence of crystal field stabilization energy on cation incorporation.
    Description: Published
    Description: 120485
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    Publication Date: 2022-02-18
    Description: Unravelling the physical state and properties of mantle rocks is crucial for understanding both plate tectonics, seismic activity, and volcanism. In this context, the knowledge of accurate elastic parameters of constituent mineral phases, and their variations with pressure (P) and temperature (T), is an essential requirement, that coupled with the thermal state of the lithosphere can provide a better understanding of its petrophysics and thermochemical structure. In this paper, we present an assessment of the thermoelastic parameters [in the form of P–V–T–K Equations of State (EoS)] of orthopyroxene, clinopyroxene, spinel and garnet based on X-Ray diffraction data and direct elastic measurements available in literature. The newly developed EoS are appropriate to describe the elastic behaviour of these phases under the most relevant P–T conditions and bulk compositions of the Earth’s mantle. In combination with the published EoS for mantle olivine and magnesiochromite, these EoS are suitable to calculate the physical properties of mantle peridotites and their variation with P and T. Thanks to these EoS, we can evaluate how the variations in bulk composition and thermal regimes affect the density structure of the lithospheric mantle. Accordingly, the density structure of fertile and depleted peridotitic systems was calculated along the 35, 45 and 60 mWm􀀀 2 geothermal gradients at P comprised between 1 and 8 GPa. Under very cold geothermal gradients, the density of both fertile and depleted peridotitic systems progressively increases with depth, whereas under relatively hot conditions a first downwards decrease from 1 to ca 3 GPa is observed, followed by an increase downward. In mantle sections characterized by intermediate geotherms (45 mWm􀀀 2), the behaviour of the two systems differs up to ca 4 GPa, as the density of the depleted system remains nearly constant down to this depth whereas it moderately increases in the fertile system. The results of our simplified parameterisation, in agreement with classical thermodynamic modelling, indicate that the density structure of the lithospheric mantle is predominantly controlled by the P – T gradient variations, with some compositional control mostly arising at cold-intermediate thermal conditions. Integrated by geophysical and thermodynamic modelling, the newly developed and selected EoS could provide an alternative strategy to infer the elastic properties of mineral phases and peridotite rocks, under the most relevant P–T conditions and compositions of the Earth’s mantle, without requiring sets of end-member properties and solution models.
    Description: Published
    Description: 106483
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: 4T. Sismicità dell'Italia
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    Publication Date: 2022-02-18
    Description: The purpose of the present paper is to investigate the effects of variable eruption source parameters on volcanic plume transport in the Mediterranean basin after the paroxysm of Mount Etna on 23 November 2013. This paroxysm was characterized by a north-east transport of ash and gas, caused by a low-pressure system in northern Italy. It is evaluated here in a joint approach considering the WRF-Chem model configured with eruption source parameters (ESPs) obtained elaborating the raw data from the VOLDORAD-2B (V2B) Doppler radar system. This allows the inclusion of the transient and fluctuating nature of the volcanic emissions to accurately model the atmospheric dispersion of ash and gas. Two model configurations were considered: the first with the climax values for the ESP and the second with the time-varying ESP according to the time profiles of the mass eruption rate recorded by the V2B radar. It is demonstrated that the second configuration produces a considerably better comparison with satellite retrievals from different sensors platforms (Ozone Mapping and Profiler Suite, Meteosat Second-Generation Spinning Enhanced Visible and Infrared Imager, and Visible Infrared Imaging Radiometer Suite). In the context of volcanic ash transport dispersion modeling, our results indicate the need for (i) the use of time-varying ESP, and (ii) a joint approach between an online coupled chemical transport model like WRF-Chem and direct near-source measurements, such as those carried out by the V2B Doppler radar system.
    Description: Published
    Description: 4037
    Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Description: 7A. Geofisica per il monitoraggio ambientale
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Description: 1IT. Reti di monitoraggio e sorveglianza
    Description: 3IT. Calcolo scientifico
    Description: 6IT. Osservatori non satellitari
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Publication Date: 2022-02-18
    Description: The Mediterranean Basin is characterized by a significant variability in tectonic behaviour, ranging from subsidence to uplifting. However, those coastal areas considered to be tectonically stable show coastal landforms at elevations consistent with eustatic and isostatic sea level change models. In particular, geomorphological indicators—such as tidal notches or shore platforms—are often used to define the tectonic stability of the Mediterranean coasts. We present the results of swim surveys in nine rocky coastal sectors in the central Mediterranean Sea using the Geoswim approach. The entire route was covered in 22 days for a total distance of 158.5 km. All surveyed sites are considered to have been tectonically stable since the last interglacial (Marine Isotope Stage 5.5 [MIS 5.5]), because related sea level markers fit well with sea level rise models. The analysis of visual observations and punctual measurements highlighted that, with respect to the total length of surveyed coast, the occurrence of tidal notches, shore platforms, and other indicators accounts for 85% of the modern coastline, and only 1% of the MIS 5.5 equivalent. Therefore, only 1% of the surveyed coast showed the presence of fossil markers of paleo sea levels above the datum. This significant difference is mainly attributable to erosion processes that did not allow the preservation of the geomorphic evidence of past sea level stands. In the end, our research method showed that the feasibility of applying such markers to define long-term tectonic behaviour is much higher in areas where pre-modern indicators have not been erased, such as at sites with hard bedrock previously covered by post-MIS 5.5 continental deposits, e.g., Sardinia, the Egadi Islands, Ansedonia, Gaeta, and Circeo. In general, the chances of finding such preserved indicators are very low.
    Description: Published
    Description: 2127
    Description: 4A. Oceanografia e clima
    Description: 7A. Geofisica per il monitoraggio ambientale
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Publication Date: 2022-02-18
    Description: We applied a new version of physics-based earthquake simulator upon a seismogenic model of the Italian seismicity derived from the latest version of the Database of Individual Seismogenic Sources (DISS). We elaborated appropriately for their use within the simulator all fault systems identified in the study area. We obtained synthetic catalogs spanning hundreds of thousands of years. The resulting synthetic seismic catalogs exhibit typical magnitude, space and time features that are comparable to those obtained by real observations. A typical aspect of the observed seismicity is the occurrence of earthquake sequences characterized by multiple main shocks of similar magnitude. Special attention was devoted to verifying whether the simulated catalogs include this notable aspect, by the use of an especially developed computer code. We found that the phenomenon of Coulomb stress transfer from causative to receiving source patches during an earthquake rupture has a critical role in the behavior of seismicity patterns in the simulated catalogs. We applied the simulator to the seismicity of the northern and central Apennines and compared the resulting synthetic catalog with the observed seismicity for the period 1650–2020. The result of this comparison supports the hypothesis that the occurrence of sequences containing multiple mainshocks is not just a casual circumstance.
    Description: Published
    Description: 2062
    Description: 2T. Deformazione crostale attiva
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: 4T. Sismicità dell'Italia
    Description: JCR Journal
    Keywords: numerical modeling ; earthquake simulator ; statistical methods ; earthquake clustering ; 04.06. Seismology ; 04.07. Tectonophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Publication Date: 2022-02-18
    Description: Plutons in crustal shear zones may exploit inherited structures, interfere with strain localizing or be deformed passively. To constrain the relative timing of such tectono-magmatic relationships in natural settings is not always straight-forward. We here present sandbox-type analogue model experiments simulating magma emplacement into simple and transtensional crustal shear zones to test the diagnostic potential of pluton shape with respect to timing and setting. Observations based on surface deformation and intrusion shape exemplify the interplay between evolving and inherited tectonic structures and magma uprising. We observe markedly asymmetric intrusions in association with dikes reflecting the regional stresses, fault pattern and finite strain field. At the same time, the presence of an intrusion modifies the tectonic evolution, but only transiently, resulting in short-lived faults, reactivation and inversion. Diagnostic attributes include the pluton’s aspect ratio, its orientation and amplitude as well as dike association. Accordingly, syn-tectonic intrusions show the highest pluton amplitudes, but only intermediate elongation compared to other scenarios. They are oriented parallel to Riedel shears in simple shear, respectively to the compression direction in transtension. Post-tectonic intrusions are least elongated, have medium amplitudes and exploit Riedel shears. Pre-tectonic intrusions are characterized by lowest amplitudes but the highest aspect ratios and are parallel to the finite elongation direction. Intrusions in transtensional shear zones are generally of less elongate than those in simple shear zones. Experimental results are tested against observations from natural examples validating the diagnostic potential of pluton shape for the timing and the tectonic setting of the emplacement.
    Description: Published
    Description: 104417
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Publication Date: 2022-02-16
    Description: On September 6, 2017, the solar active region AR 2673 emitted two solar flares: the first at 08:57 UT (X2.2) and the second at 11:53 UT (X9.3); both were powerful enough to black-out high and low frequency radio waves (where UT is universal time). The X9.3 was the strongest solar flare event in the past decade. In this study, we took the advantage of these two extreme flare events to investigate corresponding effects on the ionosphere using multi-instrument observations from magnetometers, Global Positioning System – Total Electron content (GPS-TEC) receivers, ionosondes and Swarm satellites over a large geographical extent covering South American, African and European sectors. During the X2.2 flare, European and African sectors were sunlit and during X9.3 European, African, and South American sectors were sunlit and exposed to the solar flare radiation. During the X2.2 flare, there was an ionosonde blackout for a duration of about 45 min, while during the X9.3 flare this blackout lasted for 1 h and 30 min. The blackout are seen over a large global extent which demonstrates the severity of solar flare events in disrupting the radio communication. The horizontal component of Earth’s geomagnetic field has shown ripples and enhancements during these flare events. The ionospheric Vertical Total Electron Content (VTEC) showed a positive phase along with an intensification of the Equatorial Ionization Anomaly (EIA) over the South American and African sectors. The dynamical and physical processes associated with the TEC and EIA variabilities due to solar flare are discussed.
    Description: Published
    Description: 1775-1791
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: 2A. Fisica dell'alta atmosfera
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Publication Date: 2022-02-16
    Description: This investigation uses simultaneous observations from all-sky imager system and an ionosonde collocated at Araguatins (5.65° S, 48.07° W and dip-latitude of 4.1° S), a near-equatorial region in Brazil. These simultaneous observations were used to investigate the occurrence of plasma bubbles and blobs in the field of the imaging system and their association with atypical range Spread-F signature in ionograms. Also, in-situ observation of plasma density from Swarm satellites were used to support the ground-based observations. Using a few cases, a methodology will be established to identify in the plasma blobs (atypical ESF) in the ionograms when there is the simultaneous observation of plasma bubbles and blobs in the field of view of the ionosonde. For this purpose, simultaneous sequence of OI 630.0 nm nightglow images and ionograms are presented for different case studies; 1. when there is the absence of a plasma bubble or blob, 2. when there is only the occurrence of plasma bubbles and 3. when there is the occurrence of plasma bubbles and blobs, in order to compare traces in the ionogram in all these case studies. With these we can cover all kinds of signatures in the ionograms corresponding to no irregularities, plasma bubbles only and plasma bubbles-blobs. These OI 630.0 nm nightglow and ionograms recorded simultaneously make it possible to establish a novel methodology to recognize in ionograms cases when there is the occurrence of Spread-F signature associated with bubble-blob in the FOV of the ionosonde.
    Description: Published
    Description: 2416-2438
    Description: 2A. Fisica dell'alta atmosfera
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Publication Date: 2022-02-16
    Description: In seismic modelling, fault planes are normally assumed to be flat due to the lack of data which can constrain fault morphology. However, incorporating 3D fault morphology is important for modelling several phenomena, for example calculating mainshock induced stress changes. We utilize a data-analytical method to unveil the 3D rupture morphology of faults using unsupervised clustering techniques applied to earthquake hypocenters in seismic sequences. We apply this method to the 2009 L’Aquila seismic sequence which involved a MW 6.1 mainshock on April 6th. We use a dataset of about 50,000 relocated events, mostly microearthquakes, reaching magnitude of completeness equal to 0.7. Clustering distinguishes the earthquakes as occurring in three main clusters along with other minor fault segments. We then represent the morphology of the main Paganica fault system (responsible for the largest mainshock) using splines. This method shows promise as a step toward robustly and quickly obtaining 3D rupture morphologies where earthquake sequences have been monitored. The 3D model is presented interactively online, and the processing is presented in an interactive Jupyter Notebook (https://bit.ly/2MnCFdj).
    Description: Published
    Description: 228756
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: JCR Journal
    Keywords: Fault morphology Clustering L’Aquila earthquake sequence ; Clustering ; L’Aquila earthquake sequence
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Publication Date: 2022-02-17
    Description: The interaction between fluids and tectonic structures such as fault systems is a muchdiscussed issue. Many scientific works are aimed at understanding what the role of fault systems in the displacement of deep fluids is, by investigating the interaction between the upper mantle, the lower crustal portion and the upraising of gasses carried by liquids. Many other scientific works try to explore the interaction between the recharge processes, i.e., precipitation, and the fault zones, aiming to recognize the function of the abovementioned structures and their capability to direct groundwater flow towards preferential drainage areas. Understanding the role of faults in the recharge processes of punctual and linear springs, meant as gaining streams, is a key point in hydrogeology, as it is known that faults can act either as flow barriers or as preferential flow paths. In this work an investigation of a fault system located in the Nera River catchment (Italy), based on geo-structural investigations, tracer tests, geochemical and isotopic recharge modelling, allows to identify the role of the normal fault system before and after the 2016–2017 central Italy seismic sequence (Mmax = 6.5). The outcome was achieved by an integrated approach consisting of a structural geology field work, combined with GIS-based analysis, and of a hydrogeological investigation based on artificial tracer tests and geochemical and isotopic analyses.
    Description: Published
    Description: 1499
    Description: 2IT. Laboratori analitici e sperimentali
    Description: JCR Journal
    Keywords: tracer tests; isotope hydrology; faults; carbonate aquifers; earthquakes; Mts. Sibillini; central Italy ; 03.02. Hydrology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Publication Date: 2022-02-22
    Description: The westernmost Mediterranean hosts part of the plate boundary between the European and African tectonic plates. Based on the scattered instrumental seismicity, this boundary has been traditionally interpreted as a wide zone of diffuse deformation. However, recent seismic images and seafloor mapping studies support that most of the plate convergence may be accommodated in a few tectonic structures, rather than in a broad region. Historical earthquakes with magnitudes Mw 〉 6 and historical tsunamis support that the low-to-moderate instrumental seismicity might also have led to underestimation of the seismogenic and tsunamigenic potential of the area. We evaluate the largest active faults of the westernmost Mediterranean: the reverse Alboran Ridge, and the strike-slip Carboneras, Yusuf and Al-Idrissi fault systems. For the first time, we use a dense grid of modern seismic data to characterize the entire dimensions of the main fault systems, accurately describe the geometry of these structures and estimate their seismic source parameters. Tsunami scenarios have been tested based on 3D-surfaces and seismic source parameters, using both uniform and heterogeneous slip distributions. The comparison of our results with previous studies, based on limited information on the fault geometry and kinematics, indicates that accurate fault geometries and heterogeneous slip distributions are needed to properly assess the seismic and tsunamigenic potential in this area. Based on fault scaling relations, the four fault systems have a large seismogenic potential, being able to generate earthquakes with Mw 〉 7. The reverse Alboran Ridge Fault System has the largest tsunamigenic potential, being able to generate a tsunami wave amplitude greater than 3 m in front of the coasts of Southern Spain and Northern Africa.
    Description: Published
    Description: 106749
    Description: 6T. Studi di pericolosità sismica e da maremoto
    Description: JCR Journal
    Keywords: Western Mediterranean ; Seismogenic potential ; Tsunamigenic potential ; Numerical modelling ; Active faults ; Active seismic data ; 04.04. Geology ; 04.07. Tectonophysics ; 04.06. Seismology ; 05.08. Risk
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Publication Date: 2022-02-23
    Description: In the Tethyan realm, leucocratic rocks were recognized as dikes and layers outcropping in the ophiolitic rocks of the Western Alps, in Corsica, and in the Northern Apennines. Several authors have suggested that the origin of leucocratic rocks is associated with partial melting of cumulate gabbro. Major and trace elements composition and paragenesis provided information about the leucocratic rocks genetic processes. This research aims at disclosing, for the first time, the petrographical and geochemical features of Timpa delle Murge leucocratic rocks, Pollino Massif (southern Italy), in order to discuss their origin and geodynamic significance through a comparison with other Tethyan leucocratic rocks. These rocks are characterized by high amounts of silica with moderate alumina and iron-magnesium contents showing higher potassium contents than plagiogranites, due to plagioclase alteration to sericite. Plagioclase fractionation reflects negative Eu anomalies indicating its derivation from gabbroic crystal mushes. The chondrite normalized REEs patterns suggest the participation of partial melts derived from a metasomatized mantle in a subduction environment. The results reveal some similarities in composition with other Tethyan leucocratic rocks, especially those concerning Corsica and the Northern Alps. These new data provide further clues on the origin of these leucocratic rocks and the Tethyan area geodynamic evolution.
    Description: Published
    Description: 1264
    Description: 2TR. Ricostruzione e modellazione della struttura crostale
    Description: JCR Journal
    Keywords: leucocratic rocks; geochemistry; fractional crystallization; ophiolite; geodynamic evolution; Pollino Massif; Southern Italy ; Petrography and Geochemistry of the Leucocratic Rocks in the Ophiolites from the Pollino Massif (Southern Italy)
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Publication Date: 2022-02-23
    Description: We investigate crustal seismic attenuation by the coda quality parameter (Qc) in the Gargano area (Southern Italy), using a recently released dataset composed of 191 small earthquakes (1.0 ≤ ML ≤ 2.8) recorded by the local OTRIONS and the Italian INGV seismic networks, over three years of seismic monitoring. Following the single back-scattering theoretical assumption, Qc was computed using different frequencies (in the range of 2–16 Hz) and different lapse times (from 10 to 40 s). The trend of Qc vs. frequency is the same as that observed in the adjacent Umbria-Marche region. Qc at 1 Hz varies between 11 and 63, indicating that the area is characterized by active tectonics, despite the absence of high-magnitude earthquakes in recent decades. The 3D mapping procedure, based on sensitivity kernels, revealed that the Gargano Promontory is characterized by very low and homogeneous Qc at low frequencies, and by high and heterogeneous Qc at high frequencies. The lateral variations of Qc at 12 Hz follow the trend of the Moho in this region and are in good agreement with other geophysical observations.
    Description: The computational work has been executed on the IT resources of the ReCaS- Bari data center, which have been made available by two projects financed by the MIUR (Italian Ministry for Education, University and Re-search) in the “PON Ricerca e Competitività 2007–2013” Program: ReCaS (Azione I-Interventi di rafforzamento strutturale, PONa3_00052, Avviso 254/Ric) and PRISMA (Asse II-Sostegno all’innovazione, PON04a2_A).
    Description: Published
    Description: 7512
    Description: 7T. Variazioni delle caratteristiche crostali e "precursori"
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Publication Date: 2022-02-21
    Description: Within an E.U.-funded project, BESS (Pocket BeachManagement and Remote Surveillance System), the notion of a geographic information system is an indispensable tool for managing the dynamics of georeferenced data and information for any form of territorial planning. This notion was further explored with the creation of aWebGIS portal that will allow local and regional stakeholders/authorities obtain an easy remote access tool tomonitor the status of pocket beaches (PB) in theMaltese Archipelago and Sicily. In this paper, we provide a methodological approach for the implementation of aWebGIS necessary for very detailed dynamic mapping and visualization of geospatial coastal data; the description of the dataset necessary for the monitoring of coastal areas, especially the PBs; and a demonstration of a case study for the PBs of Sicily andMalta by using the methodology and the dataset used during the BESS project. Detailed steps involved in the creation of theWebGIS are presented. These include data preparation, data storage, and data publication and transformation into geo-services. With the help of different Open Geospatial Consortium protocols, theWebGIS displays different layers of information for 134 PBs including orthophotos, sedimentological/geomorphological beach characteristics, shoreline evolution, geometric and morphological parameters, shallow water bathymetry, and photographs of pocket beaches. TheWebGIS allows not only for identifying, evaluating, and directing potential solutions to present and arising issues, but also enables public access and involvement. It reflects a platform for future local and regional coastal zone monitoring and management, by promoting public/private involvement in addressing coastal issues and providing local public administrations with an improved technology to monitor coastal changes and help better plan suitable interventions.
    Description: Published
    Description: 8233
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Publication Date: 2022-02-21
    Description: This study was developed to carry out a comprehensive radiological assessment of natural radioactivity for river sediment samples from Calabria, southern Italy, and to define a baseline background for the area on a radiation map. In the studied area, elevated levels of natural radionuclides are expected, due to the outcropping acidic intrusive and metamorphic rocks from which the radioactive elements derive. To identify and quantify the natural radioisotopes, ninety river sediment samples from nine selected coastal sampling points (ten samples for each point) were collected as representative of the Ionian and the Tyrrhenian coastline of Calabria. The samples were analyzed using a gamma ray spectrometer equipped with a high-purity germanium (HPGe) detector. The values of mean activity concentrations of 226Ra, 232Th and 40K measured for the studied samples are (21.3 6.3) Bq kg􀀀1, (30.3 4.5) Bq kg􀀀1 and (849 79) Bq kg􀀀1, respectively. The calculated radiological hazard indices showed average values of 63 nGy h􀀀1 (absorbed dose rate), 0.078 mSv y􀀀1 (effective dose outdoors), 0.111 mSv y􀀀1 (effective dose indoors), 63 Bq kg􀀀1 (radium equivalent), 0.35 (Hex), 0.41 (Hin), 0.50 (activity concentration index) and 458 Sv y􀀀1 (Annual Gonadal Equivalent Dose, AGED). In order to delineate the spatial distribution of natural radionuclides on the radiological map and to identify the areas with low, medium and high radioactivity values, the Surfer 10 software was employed. Finally, the multivariate statistical analysis was performed to deduce the interdependency and any existing relationships between the radiological indices and the concentrations of the radionuclides. The results of this study, also compared with values of other locations of the Italian Peninsula characterized by similar local geological conditions, can be used as a baseline for future investigations about radioactivity background in the investigated area.
    Description: Published
    Description: 1729
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Publication Date: 2022-02-21
    Description: This Special Issue focuses on three main aspects of coastal-transitional systems, namely, complexity, vulnerability, and sensitivity; underlining the key role played by highly integrated multidisciplinary approaches to unraveling the records of the present and the past. This Issue aims to illustrate a set of recent advances in field and remote sensing observations, laboratory techniques, numerical modelling, and statistical analyses applied to the quantitative monitoring of coastal areas and the reconstruction of past landscape dynamics under changing climate-RSL conditions.
    Description: Published
    Description: 1182
    Description: 5A. Ricerche polari e paleoclima
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Publication Date: 2022-02-21
    Description: The Gulf of La Spezia (GLS) in Northwest Italy is a rocky embayment with low fluvial influence facing the Mediterranean Sea. Past landscape dynamics were investigated through a multiproxy, facies-based analysis down to a core depth of 30 m. The integration of quantitative ostracod, foraminifera, and pollen analyses, supported by radiocarbon ages, proved to be a powerful tool to unravel the late Quaternary palaeoenvironmental evolution and its forcing factors. The complex interplay between relative sea-level (RSL), climatic changes, and geomorphological features of the embayment drove four main evolution phases. A barrier–lagoon system developed in response to the rising RSL of the Late Pleistocene (likely the Last Interglacial). The establishment of glacial conditions then promoted the development of an alluvial environment, with generalised erosion of the underlying succession and subsequent accumulation of fluvial strata. The Holocene transgression (dated ca. 9000 cal year BP) caused GLS inundation and the formation of a low-confined lagoon basin, which rapidly turned into a coastal bay from ca. 8000 cal year BP onwards. This latter environmental change occurred in response to the last Holocene stage of global sea-level acceleration, which submerged a morphological relief currently forming a drowned barrier-island complex in the embayment.
    Description: Published
    Description: 427
    Description: 5A. Ricerche polari e paleoclima
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Publication Date: 2022-02-21
    Description: High-resolution images of Mars from National Aeronautics and Space Administration (NASA) rovers revealed mm-size loose haematite spherulitic deposits (nicknamed “blueberries”) similar to terrestrial iron-ooids, for which both abiotic and biotic genetic hypotheses have been proposed. Understanding the formation mechanism of these haematite spherules can thus improve our knowledge on the possible geologic evolution and links to life development on Mars. Here, we show that shape, size, fabric and mineralogical composition of the Martian spherules share similarities with corresponding iron spherules currently forming on the Earth over an active submarine hydrothermal system located off Panarea Island (Aeolian Islands, Mediterranean Sea). Hydrothermal fluids associated with volcanic activity enable these terrestrial spheroidal grains to form and grow. The recent exceptional discovery of a still working iron-ooid source on the Earth provides indications that past hydrothermal activity on the Red Planet is a possible scenario to be considered as the cause of formation of these enigmatic iron grains.
    Description: Published
    Description: 460
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...