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Weighted Functional Data Analysis for the Calibration of a Ground Motion Model in Italy
No full textMotivated by the crucial implications of Ground Motion Models in terms of seismic hazard analysis and
civil protection planning, this work extends a scalar Ground Motion Model for Italy to the framework of
Functional Data Analysis. The inherent characteristic of seismic data to be incomplete over the observation
domainofoscillation periods entails embedding the analysis in the context of partially observed functional
data and performing data reconstruction. This work proposes a novel methodology that accounts for the
fact that parts of the curves are directly observed and other parts are reconstructed, thus, characterized by
greateruncertainty.Themethoddefinesobservation-specificfunctionalweights,whichentertheestimation
process to reduce the impact that the less reliable portions of the curves have on the final estimates. The
classical methods of smoothing and concurrent functional regression are extended to include weights. The
advantages of the proposed methodology are assessed on synthetic data. Eventually, the weighted func
tional analysis performed on seismological data is shown to provide a natural smoothing and stabilization
of the spectral estimates of the Ground Motion Model considered. Supplementary materials for this article
are available online.Published1697-1708OST2 Deformazione e Hazard sismico e da maremotoJCR Journa
Science and scientists from children’s point of view: comparison and gender outlooks among 2011 and 2021 primary school student drawings
No full textThis article explores the evolving perceptions of science and scientists from the unique perspective of Italian primary school children by comparing students’ drawings from two distinct periods, 2011 and 2021. A notable research gap exists in understanding how the perceptions of science and scientists among primary school children have evolved over time and if it is different for gender and grade level. The methodology involves a qualitative analysis of drawings examining the presence, the number and gender of depicted scientists, stereotypes, scientific topics, inventions, tools, location, and accompanying speech bubbles. The statistical analysis emphasizes the differences between how girls and boys represent science and scientists. From the data, a generally positive picture of the work of scientists emerges, as well as a great level of confidence in the potential of science. Notably, while the prevailing image of a scientist is still predominantly male, the 2021 dataset demonstrates a significant increase in depictions of female scientists, primarily drawn by girls, signaling an increased sense of belonging and potential for girls to pursue careers in science. Environmental and health-related scientific themes have gained prominence, accompanied by an increase in inventive ideas. The data highlights the children’s awareness of pressing global issues, such as climate change and healthcare, caused by Covid emergency. Furthermore, the results contribute to evaluate how science showed itself over ten years, if it has led to an effective shared science and a less stereotyped image, also encouraging gender equality.The 2021-2022 edition of the INGV calendar benefited from the contribution of the NET 2021 Project, funded by the European Commission to promote the European Researchers’ Night (GA n. 955459)Published1179179OS: Terza missioneJCR Journa
Magmatic Activity in Incipient Continental Break-Up as Revealed by Coupling Melt and Fluid Inclusions
No full textDeciphering deep magmatic processes driving the onset of continental break-up is fundamental to constrain our understanding of plate tectonics. The East African Rift System (EARS) represents the only opportunity to study a currently active system on Earth undergoing distinct stages of rift evolution. We present a coupled analysis of melt and f luid inclusions in the Virunga Volcanic Province (VVP) offering unprecedented insight into the dynamics of incipient rifting and its evolution. Our study highlights that melting of distinct metasomes in the deep lithosphere is a common feature of immature rifts. In the VVP, it leads to the emission of nephelinitic and basanitic melts at Nyiragongo and Nyamulagira volcanoes, respectively. Additionally, the chemical composition of melt and f luid inclusions supports the identification of another magmatic series in the area. We suggest that the related alkali basaltic melts were produced by contemporary melting of a less enriched domain in the upper lithosphere, a process that is more commonly documented in mature rifts. Various extents of mixing and crystallization of these three distinct magmatic series occur in the lower crust beneath the VVP where the barometric estimates are consistent with the presence of a thick seismic low velocity zone (LVZ). The involvement of alkali basaltic melts in the regional magma production would be also detected in the spread of gas emissions in the rift valley and in the fumaroles of the main active volcanoes. Melting of the corresponding mantle domain is an added source of gas release that may largely contribute to CO 2 emissions along the EARS.Publishedegae125JCR Journa
The low primordial heavy noble gas and 244Pu-derived Xe contents of Earth's convecting mantle
No full textClues to unraveling the origin and history of terrestrial volatiles lie in the noble gas record of Earth’s mantle.
However, the low abundance of heavy noble gases (Ar-Kr-Xe) in mantle-derived rocks presents a major analytical
challenge that limits our understanding of mantle volatile evolution. Here, we employ a new technique of ultrahigh
precision dynamic mass spectrometry to measure Ar-Kr-Xe isotopes in mantle-derived gas collected from
Mt. Etna (Italy) and Eifel (Germany), which both tap depleted convecting mantle reservoirs. We find that the
fractions of primordial Kr-Xe from accretionary sources (≤ 7 % of non-radiogenic, non-fissiogenic isotopes) and
244Pu-derived 136Xe (≤ 9.8 ± 9.3 % of total fissiogenic Xe) are both markedly lower than previously estimated.
For Mt. Etna, we find an apparent lack of detectable primordial Xe, which could reflect an additional contribution
from recycled atmospheric volatiles from nearby subduction. In addition, slight excesses of 238U-derived
fissiogenic Xe relative to the upper mantle composition may reflect the contribution of a crustal component
related to the occurrence of a HIMU (“high μ” where μ = 238U/204Pb)-type source in Mt. Etna volcanic products.
The low primordial heavy noble gas and 244Pu-derived Xe contents of Earth’s convecting mantle, as derived from
these new data, requires extensive volatile loss during terrestrial accretion, followed by long-term degassing and
pervasive overprinting of primordial heavy noble gases by subduction recycling. In addition, we suggest that
quantitative incompatible element (including Pu, U) extraction to the Hadean crust and subsequent reintroduction
of U via subduction could have contributed to lowering the ultimate fraction of 244Pu-derived 136Xe in
the upper mantle. The differences observed between this study and other upper mantle Xe studies may reflect
mantle source heterogeneities (e.g. due to the heterogeneous overprinting of mantle volatiles by subduction) but
could also result from analytical inconsistencies and/or subsurface isotope fractionation in natural systems.
Future studies are crucial to gain insight into the origin of these different results.Published118886OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
The Contribution of Underwater Systems for the Study of the Emerged Volcanoes and Seamounts of Southern Italy
No full textThis chapter examines the signals collected by multidisciplinary seafloor observatories and subsea instruments in Southern Tyrrhenian region. It provides an overview of the systems, emphasizing the key characteristics of the sensors. Various types of signals (such as seismological, magnetic, deformation, and oceanographic data), detected underwater and related to onshore and offshore volcanic structures, are analysed and compared, where possible, with data from land-based stations. The focus is on several case studies from Southern Italy, a region of high geological activity, and tectonic and volcanic features. This area includes two of the world's most active volcanoes, Mt. Etna and Stromboli, as well as the Marsili Seamount, the largest volcanic seamount in the Tyrrhenian Sea bathyal plain. Although extensive research has been conducted on Mt. Etna and Stromboli, the functioning of their deepest and submerged parts, as well as the nature and evolution of their activity, remains incomplete. This is also particularly true for volcanic seamounts like Marsili. Seafloor instrumentation, including Ocean Bottom Seismometers and Hydrophones (OBSHs), and multiparametric seafloor observatories play a crucial role in monitoring volcanic activity contributing significantly to understanding of volcanic behaviour and its temporal evolution. Additionally, swath bathymetry data aid in visualizing tectonic and volcanic structures.OST5 Verso un nuovo Monitoraggi
4C EARTHQUAKE RECORDINGS AT GRAN SASSO FOR A BETTER COMPREHENSION OF GROUND MOTION
No full texthttps://proceedings-wcee.org/view.html?id=25477&conference=18WCEEThe Gran Sasso underground laboratory (LNGS-INFN) host the GIGS seismic station of INGV national network equipped with a broad band 3-component velocimetric sensor co-located with a “ring-laser” gyroscope (designed and operated by INFN GINGERINO project) measuring the vertical ground rotation so that we can consider the whole installation as a four component rotational sensor (4C) composed by a translational 3C part and a rotational 1C part; all data collected are available in the EIDA database (https://eida.ingv.it/en/ last accessed 10-05-23). The Gran Sasso seismic station is able to record local, regional and teleseismic earthquakes, with a good signal-to-noise ratio thanks to its underground location. The 4C vertical rotational sensor is generally used to obtain the earthquake epicentral coordinates from a single-station recording by applying a traditional f-k analysis, with the benefit of solving the π ambiguity of back azimuth estimation.Publishe
TSDSystem: a framework to collect, archive and share time series data at volcanological observatories
No full textThis paper presents a framework designed to collect, archive, and share time series data coming from sensor networks at Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo (Italy), which we have developed and called Time Series Database management System (TSDSystem). The framework proposes a flexible database model for the standardization of sensor networks data and implements an optimized technology for storage and retrieval of acquired time series data. It is designed for the implementation of multiparametric databases and then suitable for development in volcanological observatories worldwide. The proposed framework provides a web service to perform writing and reading data via a standard web communication protocol, which easily enables interaction with other instruments or automatic systems. All results provided by the TSDSystem web service are represented using common data formats in the context of online services. In particular, the station networks metadata representation follows a schema inspired by the International Federation of Digital Seismograph Networks, widely known in seismology. A web GUI (graphical user interface) is provided to test and document the web service. Additionally, basic built-in web applications are supplied with the web GUI to perform joint and synchronized time series data visualization as well as representation of stations on a geographical map. The web GUI also offers administration tools for data access policy management, creation of monitoring dashboards and data publication through web pages. The framework implements an authorization system that can be used to restrict both writing or reading operations. The TSDSystem can also be a useful tool for engineering surveillance systems. The implementing code of the framework is available with an open source license on a public repository together with a user manual.PublishedJCR Journa
Inundation and evacuation of shoreline populations during landslide-triggered tsunamis: an integrated numerical and statistical hazard assessment
No full textThe volcanic island of Stromboli (southern Tyrrhenian Sea, Italy) is renowned for its persistent, periodic, low-intensity explosive activity, whose spectacular manifestations attract tens of thousands of tourists every year. However, sporadic more intense major explosive and effusive eruptions and paroxysms pose serious threats to the island. In addition to direct hazards, granular slides of volcanic debris and pyroclastic avalanches, which can rapidly reach the sea and potentially generate tsunamis, are often associated with such unpredictable eruptive activity. Due to the very fast propagation of the tsunami around the island and the consequent short tsunami warning time (ranging from less than a minute to only a few minutes), mitigation efforts and evacuation from the Strombolian coast must be carefully planned. In this paper, we describe a new GIS-assisted procedure that allows us to combine the outputs of an ensemble of 156 pre-computed landslide-generated tsunami hazard scenarios (with variable landslide volume, position, and density), statistical exposure data (i.e. the number of inhabitants and tourists), and digital geographic information to obtain a quantitative (scenario-based) risk analysis. By means of the analysis of the road network and coastal morphology, we develop a model with routes and times to reach a safe area from every pixel in the inundated area and an appraisal of the time needed to escape versus the wave arrival time. This allows us to evaluate and quantify the effectiveness of potential risk mitigation by means of evacuation. The creation of an impact score linking the predicted inundation extent and the tsunami warning signals is intended, in the long term, to be used to predict the intensity of future tsunamis and to adapt evacuation plans accordingly. The model, here applied to Stromboli, is general and can be applied to other volcanic islands. Evacuating an island hosting several thousand tourists every summer with very little warning time underlines the absolute necessity for such mitigation efforts, aimed at informing hazard planners and managers and all other stakeholders.PublishedJCR Journa
A board game meets an App… this is GeoRisk!
No full textGeoRisk is a game-learning experiment to raise awareness on disaster reduction, enforcing the ability to foster hazards before the occurrence of extreme events in an amusing way for the last two years of Primary School and the first year of the Middle School classes. The research program of risk education interactive learning involves a network of schools also in special scientific venues in a Computer Supported Collaborative Learning Education experience, also testing the efficacy of the Risk Detective (Seismic and Hydrogeological Risk) table game by the Saving Yourself APP (Volcanic, Seismic and Hydrogeological Emergencies). The resulting educational tool ensures effective dissemination on natural hazard understanding to instill a culture of safety promoting best practice. The highly innovative idea is to use an App as an authentic assessment tool. The table game stimulates and facilitates learning in a simulated situation, the App promotes authentic assessment, providing immediate feedback, which is essential for an excellent outcome (Trinchero, 2015; Bursztyn et al., 2016; Rugelj, 2016). Therefore, the engaging gaming experiences also accompanies innovation in authentic assessment and favors the correct use of technology, which can constitute a valid tool of conscious communication for the new generations.PublishedOS: Terza missioneJCR Journa
Improving the Foreshock Traffic Light Systems for Real-Time Discrimination Between Foreshocks and Aftershocks
No full textAfter a moderate-to-large earthquake, Civil Protection, scientists, the population, and decision makers immediately ask: "Was this the mainshock, or is a bigger event yet to come?" According to the current state of the art, the probability that an even larger event will occur within five days and 10 km after a moderate earthquake is typically 5%. Recent work proposes that a more specific answer to this question is possible (Gulia and Wiemer, 2019). The method allows real-time discrimination between foreshocks and aftershocks in well-monitored regions. However, so far, some expert judgments are required to adapt the technique to the case-specific data, such as defining the overall magnitude of completeness and the duration of the short-term aftershock incompleteness. Here, we introduce and retrospectively test an improved version of the foreshock traffic light system (FTLS) approach that successfully overcomes the aforementioned limits using the b-positive estimator (van der Elst, 2021). With these improvements, an FTLS assessment can be fully automated as early as one hour after an M ≥ 6 event without requiring expert judgments. We also test the updated approach on six additional sequences; the results align with the FTLS hypothesis.Published3579-3592OST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impattoJCR Journa