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3D density structure of upper mantle beneath the Antarctic plate: The influence of Moho depth
No full textIn this study, we explore the impact of using different Moho surfaces on the reconstruction of the upper mantle geophysical parameters. The study area is the subsurface of the Antarctica continent. Using the optimization program of Sequential Integrated Inversion (SII) and the gravity anomalies synthetized by a global Gravity Field Model (GFM), we reconstructed the upper mantle density and the related 3D distribution of the rho-v_SV couplings down to the depth of 400 km, with a lateral resolution of 0.5° × 0.5°. Here, we present the results obtained for four models, built with four different Moho surfaces. A correlation analysis showed that different Moho structures affect the optimization of the intensity of the anomalies and the rho-v_SV couplings. The possibility of having both a density model and a 3D distribution of the rho-v_SV couplings enables us to highlight several significant features for all models that are not disclosed by seismic tomography. Among them, a trend of positive, presumably compositional anomalies suggests the contribution of the Lambert Rift System (LRS) to the Gamburstev Mountains (GSM) uplift, which in turn may have influenced the formation of the Maud Subglacial Basin (MSB). A continuous low-density anomaly and positive rho-v_SV phase coupling anomaly, extending from the northwestern side of the Transantarctic Mountains (TAM) to Victoria Land, support the thermal buoyancy force as the causative element of the formation of the TAM. A circumscribed negative density anomaly extending up to depth of 365 km, which is associated to a negative variation in the angular coefficients of the rho-v_SV couplings, indicates the presence of an active magmatic system in the upper mantle or a Cenozoic mantle plume beneath the region of Mary Byrd Land (MBL).PNRA project: “Risposta litosferica alla dinamica del mantello e della criosfera” (D.D. n. 2164–14/11/2013 – PdR 2013/B2.06)
CINECA ISCRA Class C project (HP10CGC85K).Published2297241T. Struttura della TerraJCR Journa
Comparison between alarm-based and probability-based earthquake forecasting methods
No full textThis article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2023. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy.
All rights reserved.In a recent work, we applied the every earthquake a precursor according to scale (EEPAS) probabilistic model to the pseudo-prospective forecasting of shallow earthquakes with magni- tude M 5.0 in the Italian region. We compared the forecasting performance of EEPAS with that of the epidemic type aftershock sequences (ETAS) forecasting model, using the most recent consistency tests developed within the collaboratory for the study of earthquake predictabil- ity (CSEP). The application of such models for the forecasting of Italian target earthquakes seems to show peculiar characteristics for each of them. In particular, the ETAS model showed higher performance for short-term forecasting, in contrast, the EEPAS model showed higher forecasting performance for the medium/long-term. In this work, we compare the performance of EEPAS and ETAS models with that obtained by a deterministic model based on the occur- rence of strong foreshocks (FORE model) using an alarm-based approach. We apply the two rate-based models (ETAS and EEPAS) estimating the best probability threshold above which we issue an alarm. The model parameters and probability thresholds for issuing the alarms are calibrated on a learning data set from 1990 to 2011 during which 27 target earthquakes have occurred within the analysis region. The pseudo-prospective forecasting performance is as- sessed on a validation data set from 2012 to 2021, which also comprises 27 target earthquakes. Tests to assess the forecasting capability demonstrate that, even if all models outperform a purely random method, which trivially forecast earthquake proportionally to the space–time occupied by alarms, the EEPAS model exhibits lower forecasting performance than ETAS and FORE models. In addition, the relative performance comparison of the three models demonstrates that the forecasting capability of the FORE model appears slightly better than ETAS, but the difference is not statistically significant as it remains within the uncertainty level. However, truly prospective tests are necessary to validate such results, ideally using new testing procedures allowing the analysis of alarm-based models, not yet available within the CSEP.Published1541–1551OST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impattoJCR Journa
MVC_2021-1
No full textL'Istituto Nazionale di Geofisica e Vulcanologia (INGV) è componente del Servizio Nazionale di Protezione Civile, ex articolo 6 della legge 24 febbraio 1992 n. 225 ed è Centro di Competenza per i fenomeni sismici, vulcanici e i maremoti per il Dipartimento della Protezione Civile Nazionale (DPC). L’Osservatorio Vesuviano, Sezione di Napoli dell’INGV, ha nei suoi compiti il monitoraggio e la sorveglianza H24/7 delle aree vulcaniche attive campane (Vesuvio, Campi Flegrei e Ischia). Tali attività sono disciplinate dall’Accordo-Quadro (AQ) sottoscritto tra il DPC e l’INGV per il decennio 2012-2021 e sono dettagliate negli Allegati A e B del suddetto AQ. Il presente Rapporto sul Monitoraggio dei Vulcani Campani rappresenta l’attività svolta dall’Osservatorio Vesuviano e dalle altre Sezioni INGV impegnate nel monitoraggio dell’area vulcanica campana nel primo semestre 2021.Istituto Nazionale di Geofisica e Vulcanologia
Dipartimento della Protezione CivileUnpublished4V. Processi pre-eruttivi6SR VULCANI – Servizi e ricerca per la società1IT. Reti di monitoraggio e sorveglianza2IT. Laboratori analitici e sperimentali4IT. Banche dat
La Sassa cave: Isotopic evidence for Copper Age and Bronze Age population dynamics in Central Italy
No full textThis study focuses on the changes in diet and mobility of people buried in the La Sassa cave (Latium, Central Italy) during the Copper and Bronze Ages to contribute to the understanding of the complex contemporary population dynamics in Central Italy. To that purpose, carbon and nitrogen stable isotope analyses, strontium isotope analyses, and FT-IR evaluations were performed on human and faunal remains from this cave. The stable isotope analyses evidence a slight shift in diet between Copper and Bronze Age individuals, which becomes prominent in an individual, dating from a late phase, when the cave was mainly used as a cultic shelter. This diachronic study documents an increased dietary variability due to the introduction of novel resources in these protohistoric societies, possibly related to the southward spread of northern human groups into Central Italy. This contact between different cultures is also testified by the pottery typology found in the cave. The latter shows an increase in cultural intermingling starting during the beginning of the middle Bronze Age. The local mobility during this phase likely involved multiple communities scattered throughout an area of a few kilometers around the cave, which used the latter as a burial site both in the Copper and Bronze ages.Publishede02886376A. Geochimica per l'ambiente e geologia medica6SR VULCANI – Servizi e ricerca per la società7SR AMBIENTE – Servizi e ricerca per la societàJCR Journa
The Lambousa (Cyprus) Fishtank in a Quasi-Stable Coastal Area of the Eastern Mediterranean, a Notable Marker for Testing GIA Models
No full textThe Lambousa fishtank, an archaeological structure entirely carved in bedrock, can be easily recognized and measured in the plan on Google Earth (GE). We surveyed in situ this excellent archaeological marker in 2016 through direct measurements using traditional field instruments, such as metric tapes and invar rods, and terrestrial photogrammetry using Structure from Motion (SfM) methods. The bedrock on which the fishtank is founded is an Upper Pleistocene calcarenite also containing Persistrombus latus. The age of the studied fishtank has not been previously published, but on the basis of the construction technique and the interpretation provided by Archaelogist and references therein, we believe that it was built in the period between 2.1 and 1.8 ka BP, like similar fishtanks in the Mediterranean area. Architectural structures consist of evident foot walks (Crepido), a stone base, and a tunnel that allows for seawater exchange during high tides. The tunnel is at the same altitude as the Crepido, which lies around the fishtank. These architectural components allow us to evaluate the palaeo-sea level with significant precision during the time when the fishtank was active. MIS 5.5 coastal deposits that outcrop in the study area are located at a maximum altitude of a few meters, while the inner margin of the MIS 5.5 terrace allows us to hypothesize “quasi-tectonic stability”. We have also obtained several predictions of the contribution from Glacial Isostatic Adjustment (GIA) to relative sea level at Lambousa for the past 3.5 kyr, according to models ICE-6G (VM5a), ICE-7G (VM7), and one of the GIA models by the Australian National University ANU) Research group.Published2803A. Geofisica marina e osservazioni multiparametriche a fondo mareJCR Journa
Multidisciplinary analysis of 3D seismotectonic modelling: a case study of Serre and Cittanova faults in the southern Calabrian Arc (Italy)
No full textActive normal faulting and uplifting, consistent with a WNW-ESE-oriented regional
extension, dominate the Quaternary tectonics of the southern Calabrian Arc. The
main tectonic structures of this extensional domain are considered to be the source
of numerous historical and recent strong earthquakes, among which the
1783 seismic sequence (M 6.5–7) was one of the most destructive earthquakes
ever recorded in Southern Italy. Previous works on the seismotectonic of the
Calabrian Arc indicate a disagreement on the attitude (E-dipping vs W-dipping)
of the main seismogenic sources slicing across southern Calabria, whereby the
seismotectonic framework is still debated. Following a multidisciplinary approach,
based on morpho-structural and seismological data, the geometry at depth of the
most reliable sources (i.e., Cittanova and Serre faults) was first modelled in a 3D
environment to retrieve information about their seismic potential. The GNSS data
from the permanent stations of RING/RDN and TopNETlive Italy networks have
been processed in order to estimate the velocity field affecting this area. Then, data
inversion allowed us to document a predominant WNW-ESE active extensional
strain orthogonally to the modelled faults, consistent with the regional dynamics.
The reliability of the model was tested using empirical relationships and fault
response modelling simulation. Furthermore, slip tendency analysis revealed the
propensity to slip of the modelled planes by applying a remote stress state derived
from the kinematic-structural survey on fault planes.PRIN 2017, under grant number “2017KT2MKE”
PIAno di inCEntivi per la RIcerca di Ateneo (PIACERI 2020/2022)Published1240051OST3 Vicino alla fagliaJCR Journa
Benchmarking a new 2.5D shallow water model for lava flows
No full textLava flows associated with effusive volcanic eruptions require accurate modelling in order to forecast potential paths of destruction.
This study presents a new depth-averaged model that overcomes the classical shallow water hypothesis by incorporating several enhancements, allowing for a more precise representation of the flow dynamics and behaviour: (i) a parabolic profile which captures the vertical variations in velocity within the flow; (ii) a non-constant vertical profile for temperature, enabling a more realistic representation of thermal gradients within the flowing lava; (iii) a viscoplastic temperature-dependent viscosity model to account for the non-Newtonian behaviour of lava; (iv) a transport equation for temperature accounting for the thermal heat exchanges with the environment and the soil. The first two modifications allow us to describe, under reasonable assumptions, the vertical structure of the flow, and for this reason, we put our model in the class of 2.5D models.
To assess the performance of our modified model, comprehensive benchmark tests are conducted using both laboratory experiments and real-world lava flow data related to the 2014–2015 Pico do Fogo, Cape Verde, effusive eruption. The benchmarking analysis demonstrates that this model accurately reproduces, with short execution times, essential flow features such as flow front advancement and cooling processes.Published107935OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
MVC_2022
No full textL'Istituto Nazionale di Geofisica e Vulcanologia (INGV) è componente del Servizio Nazionale di Protezione Civile, ex articolo 6 della legge 24 febbraio 1992 n. 225 ed è Centro di Competenza per i fenomeni sismici, vulcanici e i maremoti per il Dipartimento della Protezione Civile Nazionale (DPC). L’Osservatorio Vesuviano, Sezione di Napoli dell’INGV, ha nei suoi compiti il monitoraggio e la sorveglianza H24/7 delle aree vulcaniche attive campane (Vesuvio, Campi Flegrei e Ischia). Tali attività sono disciplinate dall’Accordo-Quadro (AQ) sottoscritto tra il DPC e l’INGV per il periodo 2022-2025 e sono dettagliate nell’Allegato Tecnico del suddetto AQ. Il presente Rapporto sul Monitoraggio dei Vulcani Campani rappresenta l’attività svolta dall’Osservatorio Vesuviano e dalle altre Sezioni INGV impegnate nel monitoraggio dell’area vulcanica campana nel 2022.Istituto Nazionale di Geofisica e Vulcanologia
Dipartimento della Protezione CivileUnpublishedOSV1: Verso la previsione dei fenomeni vulcanici pericolosiOSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciOSV3: Sviluppo di nuovi sistemi osservazionali e di analisi ad alta sensibilitàOSV4: Preparazione alle crisi vulcanich
Geochemical characterization of volcanic gas emissions at Santa Ana and San Miguel volcanoes, El Salvador, using remote-sensing and in situ measurements
No full textVolcanic degassing provides important information for the assessment of volcanic
hazards. Santa Ana and San Miguel are open vent volcanoes along the Central
American Volcanic Arc–CAVA, where the magmatism, basaltic to dacitic, is related
to the near-orthogonal convergence of the Caribbean Plate and the subducting
Cocos Plate. Both volcanoes are the most active ones in El Salvador with recent
eruptive events in October 2005 (Santa Ana) and December 2013 (San Miguel), but
still not much data on gas composition and emission are available today. At each
volcano, SO2 emissions are regularly monitored using ground-based scanning
Differential Optical Absorption Spectrometer (Scan-DOAS) instruments that are
part of the global “Network for Observation of Volcanic and Atmospheric Change”
(NOVAC). We used the data series from these NOVAC stations in order to retrieve
SO2 and minimum bromine emissions, which can be retrieved from the same
spectral data for the period 2006–2020 at Santa Ana and 2008–2019 at San
Miguel. However, BrO was not detected above the detection limit. SO2 emission
ranged from 10 to 7,760 t/d, and from 10 to 5,870 t/d for Santa Ana and San Miguel,
respectively. In addition, the SO2 emissions are complemented with in situ plume
data collected during regular monitoring surveys (2018–2020) and two field
campaigns in El Salvador (2019 and 2020). MultiGAS instruments recorded
CO2, SO2, H2S and H2 concentrations. We determined an average CO2/SO2
ratio of 2.9 ± 0.6 when peak SO2 concentration exceeded 15 ppmv at Santa
Ana, while at San Miguel the CO2/SO2 ratio was 7.4 ± 1.8, but SO2 levels reached
only up to 6.1 ppmv. Taking into account these ratios and the SO2 emissions
determined in this study, the resulting CO2 emissions are about one order of
magnitude higher than those determined so far for the two volcanoes. During the
two field campaigns Raschig tubes (active alkaline trap) were used to collect plume
samples which were analyzed with IC and ICP-MS to identify and quantify CO2,
SO2, HCl, HF, and HBr. Additionally, also 1,3,5-trimethoxybenzene (TMB)-coated
denuders were applied and subsequently analyzed by GC-MS to determine the
sum of the reactive halogen species (RHS: including Cl2, Br2
, interhalogens, hypohalous acids). The RHS to sulfur ratios at Santa Ana and San Miguel lie in the
range of 10−5. Although no new insights could be gained regarding changes with
volcanic activity, we present the most comprehensive gas geochemical data set of
Santa Ana and San Miguel volcanoes, leading to a solid data baseline for future
monitoring purposes at both volcanoes and their improved estimate of CO2, SO2
and halogens emissions. Determining the reactive fraction of halogens is a first step
towards a better understanding of their effects on the atmosphere.Published10496703V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcaniciJCR Journa
European Environmental Metadata
No full textResearch Infrastructures (RI) of the Environment Domain as defined by ESFRI cover the main four subdomains of the complex Earth system (Atmosphere, Marine, Solid Earth, and Biodiversity/Terrestrial Ecosystems), thus forming the cluster of European Environmental and Earth System Research Infrastructures (ENVRIs). The overarching goal is that at the end of the proposed project, all participating RIs have built a set of FAIR (Findable, Accessible, Interoperable, Reusable) data services which enhances the efficiency and productivity of researchers, supports innovation, enables data- and knowledge-based decisions and connects the ENVRI Cluster to the European Open Science Cloud. The focus of the proposed work is on the provision of an environmental metadata catalogue describing in detail the FAIR services produced (or enhanced) in each subdomain; the complete set of thematic data services and tools provided by the ENVRI cluster can then be exposed to the EOSC catalogue of services.Published289–294OST5 Verso un nuovo Monitoraggi