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ERMES Report INT-20230206_0000222
No full textIstituto Nazionale di Geofisica e VulcanologiaUnpublished5T. Sismologia, geofisica e geologia per l'ingegneria sismic
Seasonal Transitions in the Thermosphere Inferred from Ionospheric Observations
No full textIonospheric observations along with CHAMP/STAR neutral gas density measurements were used to retrieve thermospheric parameters and to check whether the equinox transition season exists separately from the December solstice and June solstice seasons. Juliusruh and Boulder ionosonde stations located in “far-from-pole” and “near-pole” longitudinal sectors were analyzed during deep solar minimum in 2008–2009. The results were compared to GOLD column O/N2 ratio observations. The retrieved thermospheric parameters have shown that equinoctial transition period exists separately from the winter one at Juliusruh, while column O/N2 ratios, exospheric temperatures Tex, and vertical plasma drifts related to thermospheric winds retrieved at Boulder for the winter season do not significantly differ from vernal values. This means that the December solstice season just does not exist as it merges with the vernal season in the “near-pole” longitudinal sector. The obtained results indicate that two longitudinal sectors manifest different seasonal variations both in thermospheric circulation and neutral composition.Published2022OSA3: Climatologia e meteorologia spazialeJCR Journa
Coupling Flank Collapse and Magma Dynamics on Stratovolcanoes: The Mt. Etna Example from InSAR and GNSS Observations
No full textVolcano ground deformation is a tricky puzzle in which different phenomena contribute
to the surface displacements with different spatial–temporal patterns. We documented some high
variable deformation patterns in response to the different volcanic and seismic activities occurring
at Mt. Etna through the January 2015–March 2021 period by exploiting an extensive dataset of GNSS
and InSAR observations. The most spectacular pattern is the superfast seaward motion of the
eastern flank. We also observed that rare flank motion reversal indicates that the short‐term
contraction of the volcano occasionally overcomes the gravity‐controlled sliding of the eastern flank.
Conversely, fast dike intrusion led to the acceleration of the sliding flank, which could potentially
evolve into sudden collapses, fault creep, and seismic release, increasing the hazard. A better
comprehension of these interactions can be of relevance for addressing short‐term scenarios,
yielding a tentative forecasting of the quantity of magma accumulating within the plumbing system.Published847OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
The footprint of a historical paleoearthquake: the sixth-century-CE event in the European western Southern Alps
No full textLow-deformation regions are characterized by
long earthquake recurrence intervals. Here, it is fundamental
to extend back the record of past events as much as possi ble to properly assess seismic hazards. Evidence from single
sites or proxies may be not compelling, whereas we obtain
a more substantial picture from the integration of paleo- and
archeoseismic evidence at multiple sites, eventually supple mented with historical chronicles.
In the city of Como (N Italy), we perform stratigraphic
and sedimentological analyses on the sedimentary sequences
at Via Manzoni and we document earthquake archeological
effects at the Roman baths by means of structure from mo tion and field surveys. Radiocarbon dating and chronological
constraints from the archeological site allow us to bracket
the time of occurrence of the deformations to the sixth cen tury CE. We interpret the observed deformations as due to
earthquake ground shaking and provide constraints on the
lower threshold for the triggering of such evidence.
We move toward a regional view to infer possible relevant
seismic sources by exploiting a dataset of published paleo seismic evidence in Swiss and N Italy lakes. We perform an
inverse grid search to identify the magnitude and location of
an earthquake that can explain all the positive and negative
evidence consistent with the time interval of the event dated
at Como.
Our results show that an earthquake (minimum Mw 6.32)
with epicenter located at the border between Italy and
Switzerland may account for all the observed effects; a sim ilar event in the sixth century CE has not been documented
so far by historical sources. Our study calls for the need to
refine the characterization of the local seismic hazard, espe cially considering that this region seems unprepared to face
the effects of an earthquake size similar to the one inferred
for the sixth-century-CE event.Published3407-3424JCR Journa
Multivariate statistical analysis of site effect indicators for the Montereale and Capitignano area (AQ) following the seismic sequence in central Italy (2016–2017)
No full textThis study investigates site effects for developing predictive models of site response, for
both research purposes and future geognostic applications, by using a statistical analysis
method to define possible correlations between different kinds of seismological and geological
data. The test area is the intermontane Montereale basin (Abruzzo region, Italy),
which was investigated for site effects studies and microzonation purposes because it has
been affected by the 2016–2017 Central Italy seismic sequence. The available geological
and geophysical information include geological profiles, thickness and geometry of the
sedimentary infilling, shear-wave velocity profiles, downhole and borehole data. Seismological
analysis (such as earthquake and noise spectral ratios, duration lengthening of
seismic signals) has been performed to retrieve parameters useful for seismic response. A
GIS database has been created to better manage all this information, by georeferencing all
the measurement points and results. Finally, Factor Analysis multivariate technique was
used to evaluate the most important site effect indicators, in terms of correlation between
the involved parameters, and to deduce how the geological context influences their behavior.
The performed analysis highlighted the statistical variability of the strong motion, that
depends on the position inside the basin, over the Holocene deposits, and on the edges, at
the limit between different lithologies. Moreover, some of the correlations between geological
and geophysical indicators are strongly coherent with the basin geological features.Published1875–19015T. Sismologia, geofisica e geologia per l'ingegneria sismicaJCR Journa
Assessing the impact of an updated spatial correlation model of ground motion parameters on the italian shakemap
No full textThis study develops a new spatial correlation model for Italy using the most up-to-date and densest dataset of accelerometer and velocimeter records available. The objective is to estimate the average correlation length and assess its impact on the prediction accuracy of the Italian Shakemap compared to the global model (Loth and Baker, 2013–LB13) adopted in the default configuration of the program. We compute the spatial covariance structure using a geostatistical approach based on traditional variography applied to standardized residuals within the events of a reference ground motion model (ITA10). We observe spatial clusters of the correlation lengths and a wide variability over the Italian territory linked to the profound heterogeneity of the geological and geomorphological context. The obtained estimates are then implemented within the LB13 co-regionalization model in place of the default values while assuming the same cross-correlation coefficients among spectral parameters. Although our results are quite consistent with previous models calibrated for Italy, we find that the inclusion of the new correlation lengths in the Shakemap predictions, assessed through a leave-one-out cross-validation technique, results in a non-appreciable improvement over the global model, thus indicating that the adopted approach is not able to resolve the regional features and the corresponding spatial correlation with reference to individual scenarios. These findings may suggest the need to move towards nonergodic models in the Shakemap computing to better capture the spatial variability or to determine different co-regionalisation matrices more suitable for the regional applications.Published1847–18735T. Sismologia, geofisica e geologia per l'ingegneria sismicaJCR Journa
Surveying volcanic crises exercises: From open-question questionnaires to a prototype checklist
No full textVolcanic crisis exercises are usually run to test response capabilities, communication protocols, and decision-making procedures by agencies with responsibilities to cope with scenarios of volcanic unrest with inherent uncertainty, such as volcano observatories and/or civil protection authorities. During the last decades, the use of questionnaires has been increased to evaluate people’s knowledge on volcanic hazards and their perception of risk, to better understand their preparedness to respond to emergency measures plans.
In this paper, we present a study carried out within the European Network of Observatories and Research Infrastructures for Volcanology project (EUROVOLC) focused on extracting information on the experience gained during volcanic-crisis exercises by the project’s participants and beyond. An open-ended question questionnaire was firstly distributed for a survey within the project community. Through the results obtained, we developed a user-friendly online multi-choice questionnaire that was submitted to the volcanological communities within and outside EUROVOLC. Analyzing the answers to the online questionnaire, we extracted a prototype checklist for guiding the design of such exercises in the future. Our results confirm this type of survey as a very useful tool for gathering information on participants’ experience and knowledge, able to understand which data and information may be useful when designing exercises for scientists, emergency managers and decision makers. In particular, the main lessons learnt regard the need i) to increase training activities involving people exposed to volcanic hazards and media, ii) to improve external communication tools (between players and public/media), equipment and protocols and iii) to better define decision-makers’ needs.Published107850OSV4: Preparazione alle crisi vulcanicheJCR Journa
Introduction to the Book “Bridges to Global Ethics”
No full textThis book wants to enrich the current discussion on geoethics and global ethics within the geoscience and humanities communities, providing new contents and insights elaborated by scholars with different disciplinary backgrounds.Published1-31TM. Formazion
Earthquake emergencies in Italy: SISMIKO operational task force for seismic networks rapid deployments and integration in the monitoring system
No full textSISMIKO is the operational task force at the Istituto Nazionale di Geofisica e Vulcanologia aiming at the rapid deployment of temporary seismic stations in the area hit by a significant earthquake or a seismic sequence causing concern and interest with impact on people. Decreasing the average distance between the seismic stations improves network detection, accuracy of the earthquake locations, shakemaps and strong motion parameters.
The data acquired by SISMIKO are available, without any constraints, to the entire scientific community through the EIDA portal Italy node, which assures a high level of data quality.
A national diffusion of the preconfigured seismic stations in different headquarters and a ready acquisition system, guarantee rapid response after an earthquake and allow the immediate acquisition of the data as soon as each seismic station is installed. An international FDSN network code is registered in advance and a five char codification for the station names is applied to request the ISC station codes (T).
The last emergency (no. 17) in 2022 was caused by an earthquake of Mw 5.5 in the Costa Marchigiana region, where we installed eight stations of the Y1 network the same day as the mainshock (DOI: 10.13127/SD/TBLKBA-3U6).
We present the organization and the objectives of the SISMIKO operational group and the analysis of the dataset of the latest seismic sequence carried out by the seismic surveillance service, the Italian Seismic Bulletin (BSI) and SISMIKO.PublishedBerlin8T. Sismologia in tempo reale e Early Warning Sismico e da Tsunami1SR TERREMOTI - Sorveglianza Sismica e Allerta Tsunami2SR TERREMOTI - Gestione delle emergenze sismiche e da maremoto1IT. Reti di monitoraggio e sorveglianz
Physical and chemical characterization of the Pomici di Avellino ashes (3.9 ka) from Somma-Vesuvius volcano for future health hazard assessment
No full textVolcanic ashes can threaten the human respiratory system through inhalation. In this study we investigated the
physical and chemical characteristics of volcanic ashes from the Pomici di Avellino (PdA) eruption, an Early
Bronze Age (ca. 3.9 ka) Plinian event from Somma-Vesuvius volcano, southern Italy, whose wide dispersal
affected most of the Italian peninsula. In particular, we analysed particle size, shape, composition, and surface
reactivity of samples from both proximal and distal locations. Our results indicate that some tephra layers north
of Rome have a phonolitic composition and match that of PdA eruption; they reach grain-sizes <2 μm (~13.5%),
thus having the potential to enter the deep respiratory system. Furthermore, the reactivity in free radical generation
makes these products potentially able to cause oxidative stress within cells. While commonly no volcanic
hazard assessment is made in areas far from active volcanoes, this study highlights that fine ashes from future
similar large eruptions, producing high amount of highly fragmented material, can pose a health hazard even in
remote, non-volcanic areas, hundreds of km away from the vent, suggesting that further studies on ash toxicity
(e.g., in vitro toxicity studies) are required.Published107826JCR Journa