ALBERT

Description: Il progetto di ASL “Studiare i terremoti con un sismografo didattico” ha come obiettivo la sensibilizzazione degli studenti sui temi della pericolosità e del rischio sismico tramite un coinvolgimento attivo nello studio dei terremoti. I temi che riguardano la prevenzione del rischio sismico sono infatti solitamente trattati nelle scuole attraverso i canali tradizionali della divulgazione scientifica, ovvero tramite seminari e conferenze in cui gli studenti svolgono esclusivamente un ruolo passivo. Tuttavia numerosi studi sulla didattica delle materie scientifiche [Struyf et al., 2019; Anderson, 2007; Brush & Sye, 2000] evidenziano il contributo positivo delle attività pratiche nell’apprendimento delle 74 discipline STEM (Science Technology Engineering and Mathematics). Lo scopo principale di questo progetto è rendere gli studenti protagonisti di un processo cognitivo caratterizzato dall’esperienza diretta che rappresenta un modo efficace per consolidare l’apprendimento nel medio e lungo termine [Liu et al., 2011]. Il progetto si divide in due task principali: la costruzione di un sismometro orizzontale (garden gate) e la formazione di competenze informatiche e sismologiche per acquisire ed elaborare i segnali sismici. È stato concepito come progetto pilota di uno piú ampio e ambizioso per realizzare una rete sismometrica scolastica. Il progetto del sismometro, basato sull’utilizzo di piattaforme hardware e software open source, potrebbe infatti essere replicato con costi contenuti e installato in altre scuole del territorio regionale o nazionale. Il successo della sismologia in ambito scolastico è testimoniata dal diffondersi di esperienze analoghe che, negli ultimi anni, sono state condotte principalmente all’estero: ad esempio i progetti PEPP ­ Princeton Earth Physics Project (USA) [Steinberg and Phinney, 2000], EduSeis ­ The Educational Seismograph Project (Francia, Italia) [Cantore et al., 2005], O3E ­ Observation de l’Environnement à but Éducatif pour l’École (Francia) [Aufeuvre et al., 2009], SAE ­ Sismos à l’Ecole (Francia) [Courboulex et al., 2012], Seismology at School (Regno Unito) [Denton, 2008] e più recentemente AuSIS ­ The Australian Seismometers in Schools (Australia) [Balfour et al., 2014]. Queste iniziative hanno evidenziato estremo entusiasmo da parte di docenti e studenti verso il monitoraggio sismico a carattere didattico anche in territori in cui l’attività sismica è molto sporadica. La scuola che ha aderito alla proposta è il Polo Scientifico Tecnico Professionale E. Fermi – G. Giorgi di Lucca che comprende sia Liceo Scientifico che Istituti Tecnici con indirizzi di meccanica, elettronica e informatica. Questa pluralità di indirizzi ha consentito di individuare studenti con le competenze necessarie alla realizzazione del progetto. Un gruppo ristretto di alunni selezionati tra le classi V degli Istituti tecnici ha curato la messa in opera del sismometro mentre gli studenti di una intera classe IV del Liceo scientifico hanno seguito lezioni per acquisire competenze sull’analisi del segnale sismico. Il progetto ha avuto un successo parziale. Il sismometro è stato progettato e realizzato in tutte le sue componenti e la scuola ha finanziato la costruzione di due copie del prototipo. Gli strumenti sono stati presentati in occasione della Notte Europea dei Ricercatori a Lucca nel Settembre 2019. Tuttavia l’installazione dei sismometri all’interno del plesso scolastico non è stata ancora completata. Il lavoro svolto con la classe del Liceo Scientifico è stato meno produttivo. Le principali motivazioni che hanno impedito di conseguire i risultati attesi sono: la scarsa motivazione degli studenti, le difficoltà tecniche incontrate per effettuare le lezioni di informatica per l’analisi dei segnali sismici, un numero insufficiente di ore per acquisire le competenze base di programmazione. Teniamo a precisare inoltre che, nel pieno dello spirito dei progetti “Alternanza Scuola Lavoro” e come coronamento del progetto, uno degli studenti che hanno preso parte alla progettazione del sismometro è risultato vincitore di un bando di selezione e quindi assunto come collaboratore tecnico a tempo determinato presso la Sezione di Pisa dell’INGV.

Description: Published

Description: 73-97

Description: OS: Terza missione

Description: N/A or not JCR

Description: We have provided the first estimate of scat- tering and intrinsic attenuation for the Gargano Prom- ontory (Southern Italy) analyzing 190 local earthquakes with M L ranging from 1.0 to 2.8. To separate the intrin- sic Q i and scattering Q s quality factors with the Wen- nerberg approach (1993), we have measured the direct S waves and coda quality factors ( Q 𝛽 , Q c ) in the same volume of crust. Q 𝛽 parameter is derived with the coda normalization method (Aki 1980) and Q c factor is derived with the coda envelope decay method (Sato 1977). We selected the coda envelope by performing an automatic picking procedure from T start = 1.5T S up to 30 s after origin time (lapse time T L ). All the obtained quality factors clearly increase with frequency. The Q c values correspond to those recently obtained for the area. The estimated Q i are comparable to the Q c at all frequencies and range between 100 and 1000. The Q s parameter shows higher values than Q i , except for 8 Hz, where the two estimates are closer. This implies a pre- dominance of intrinsic attenuation over the scattering attenuation. Furthermore, the similarity between Q i and Q c allows us to interpret the high Q c anomaly previ- ously found in the northern Gargano Promontory up to a depth of 24 km, as a volume of crust characterized by very low seismic dumping produced by conversion of seismic energy into heat. Moreover, most of the earth- quake foci fall in high Q i areas, indicating lower level of anelastic dumping and a brittle behavior of rocks.

Description: Published

Description: 827-846

Description: OST1 Alla ricerca dei Motori Geodinamici

Description: JCR Journal

Description: A catalogue of precisely located micro-seismicity is fundamental for investigating seismicity and rock physical properties in active tectonic and volcanic regions and for the definition of a ‘baseline’ seismicity, required for a safe future exploitation of georesource areas. In this study, we produce the first manually revised catalogue of micro-seismicity for Co. Donegal region (Ireland), an area of about 50K M2 of on-going deformation, aimed at localizing natural micro-seismic events occurred between 2012 and 2015. We develop a stochastic method based on a Markov chain Monte Carlo (McMC) sampling approach to compute earthquake hypocentral location parameters. Our results indicates that micro-seismicity is present with magnitudes lower than 2 (the highest magnitude is 2.8).The recorded seismicity is almost clustered along previously mapped NE-SW trending, steeply dipping faults and confined within the upper crust (focal depth less than 10 km). We also recorded anthropogenic seismicity mostly related to quarries' activity in the study area.

Description: Published

Description: 62-76

Description: OST1 Alla ricerca dei Motori Geodinamici

Description: JCR Journal

Description: This study focuses on two weak points of the present procedure to carry out microzoning study in near-field areas: (1) the Ground Motion Prediction Equations (GMPEs), commonly used in the reference seismic hazard (RSH) assessment; (2) the ambient noise measurements to define the natural frequency of the near surface soils and the bedrock depth. The limitations of these approaches will be discussed throughout the paper based on the worldwide and Italian experiences performed after the 2009 L’Aquila earthquake and then confirmed by the most recent 2012 Emilia Romagna earthquake and the 2016–17 Central Italy seismic sequence. The critical issues faced are (A) the high variability of peak ground acceleration (PGA) values within the first 20–30 km far from the source which are not robustly interpolated by the GMPEs,(B) at the level 1 microzoning activity, the soil seismic response under strong motion shaking is characterized by microtremors’ horizontal to vertical spectral ratios (HVSR) according to Nakamura’s method. This latter technique is commonly applied not being fully compliant with the rules fixed by European scientists in 2004, after a 3-year project named Site EffectS assessment using AMbient Excitations (SESAME). Hereinafter, some “best practices” from recent Italian and International experiences of seismic hazard estimation and microzonation studies are reported in order to put forward two proposals: (a) to formulate site-specific GMPEs in near-field areas in terms of PGA and (b) to record microtremor measurements following accurately the SESAME advice in order to get robust and repeatable HVSR values and to limit their use to those geological contests that are actually horizontally layered.

Description: Published

Description: id 11

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: JCR Journal

Description: Set of data and metadata that characterize a site hosting a seismic station

Description: In this paper we describe an advanced database for the site characterization of seismic stations, named “CRISP—Caratterizzazione della RIsposta sismica dei Siti Permanenti della rete sismica” (http:// crisp. ingv. it, quoted with https:// doi. org/ 10. 13127/ crisp), designed for the Italian National Seismic Network (Rete Sismica Nazionale, RSN, operated by Istituto Nazionale di Geofisica e Vulcanologia). For each site, CRISP collects easily accessible station information, such as position, type(s) of instrumentation, instrument housing, thematic map(s) and descriptive attributes (e.g., geological characteristics, etc.), seismic analysis of recordings, and available geophysical investigations (shear-wave velocity [VS] profile, non-linear decay curve). The archive also provides key proxy indicators derived from the available data, such as the time-averaged shear-wave velocity of the upper 30 m from the surface ( VS30) and site and topographic classes according to the different seismic codes. Standardized procedures have been applied as motivated by the need for a homogenous set of information for all the stations. According to European Plate Observing System infrastructural objectives for the standardization of seismological data, CRISP is integrated into pre-existing INGV instrument infrastructures, shares content with the Italian Accelerometric Archive, and complies map information about the stations, as well as local geology, through web services managed by Istituto Superiore per la Protezione e la Ricerca Ambientale. The design of the CRISP archive allows the database to be continually updated and expanded whenever new data are available from the scientific community, such as the ones related to new seismic stations, map information, geophysical surveys, and seismological analyses.

Description: Published

Description: 2415 - 2439

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: JCR Journal

Description: Lifelines, such as pipelines, roads, and tunnels, are critical infrastructure and when crossing active tectonic faults, a reliable estimation of the fault displacement in case of an earthquake is required. The first and simplest approach is to use empirical fault scaling relations to compute the design fault displacement, but this may result in an unknown level of safety. Thus, the probabilistic fault displacement hazard analysis (PFDHA) is the appropriate tool to assess the fault displacement hazard within a performance-based framework. Based upon an established PFDHA model, we present a simplified approach for engineering applications focusing on the lifeline–fault crossing along with appropriate simplifications and assumptions to extend its applicability to numerous faults. The aim is to provide a structure-independent approach of PFDHA that can be used when a site-specific study is not required, not possible (e.g., absence of recent sediments for dating past events), or too cumbersome, e.g., for lifeline route selection. Additionally, an in-depth investigation is presented on the key parameters, such as maximum earthquake magnitude, fault length, recurrence rate of all earthquakes above a minimum magnitude, and lifeline-fault crossing site, and how they affect the hazard level. This approach will be the basis for deriving hazard-consistent expressions to approximate fault displacement for use within the Eurocodes. The latter is intended to serve as a compromise between hazard-agnostic fault scaling relations and a comprehensive PFDHA, which requires detailed calculations and site-specific seismological data.

Description: Open access funding provided by HEAL-Link Greece. The current work has been undertaken as part of the Horizon 2020 Seismology and Earthquake Engineering Research Infrastructure Alliance in Europe (SERA, Grant Agreement No. 730900). The first and the third author have received partial funding from the European Union’s Horizon 2020 research and innovation programme “METIS-Seismic Risk Assessment for Nuclear Safety” under Grant Agreement No. 945121. Also, the financial support provided by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “2nd Call for H.F.R.I. Research Projects to support Faculty Members & Researchers”, Project "TwinCity—Climate-Aware Risk and Resilience Assessment of Urban Areas under Multiple Environmental Stressors via Multi-Tiered Digital City Twinning ", (Number: 2515) is gratefully acknowledged.

Description: Published

Description: 4821–4849

Description: 2T. Deformazione crostale attiva

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: 6T. Studi di pericolosità sismica e da maremoto

Description: JCR Journal

Description: Machine learning, with its advances in deep learning has shown great potential in analyzing time series. In many scenarios, however, additional information that can potentially improve the predictions is available. This is crucial for data that arise from e. g., sensor networks that contain information about sensor locations. Then, such spatial information can be exploited by modeling it via graph structures, along with the sequential (time series) information. Recent advances in adapting deep learning to graphs have shown potential in various tasks. However, these methods have not been adapted for time series tasks to a great extent. Most attempts have essentially consolidated around time series forecasting with small sequence lengths. Generally, these architectures are not well suited for regression or classification tasks where the value to be predicted is not strictly depending on the most recent values, but rather on the whole length of the time series. We propose TISER-GCN, a novel graph neural network architecture for processing, in particular, these long time series in a multivariate regression task. Our proposed model is tested on two seismic datasets containing earthquake waveforms, where the goal is to predict maximum intensity measurements of ground shaking at each seismic station. Our findings demonstrate promising results of our approach—with an average MSE reduction of 16.3%—compared to the best performing baselines. In addition, our approach matches the baseline scores by needing only half the input size. The results are discussed in depth with an additional ablation study.

Description: Interreg North-West Europe program (Interreg NWE), project Di-Plast - Digital Circular Economy for the Plastics Industry (NWE729). INGV Pianeta Dinamico 2021 Tema 8 SOME (CUP D53J1900017001) funded by Italian Ministry of University and Research “Fondo finalizzato al rilancio degli investimenti delle amministrazioni centrali dello Stato e allo sviluppo del Paese, legge 145/2018.

Description: Published

Description: 317–332

Description: 8T. Sismologia in tempo reale e Early Warning Sismico e da Tsunami

Description: JCR Journal

Description: N.N. Ambraseys left us a wealth of papers and volumes on a number of topics; many of them concern the historical earth- quake investigation. One of the last works is the 2009 volume (Ambraseys in Earthquakes in the Eastern Mediterranean and the Middle East: a multidisciplinary study of 2000 years of seismicity, Cambridge, Cambridge, UK, 2009), where he summarizes the results of more than thirty years of investigation through archives and libraries, covering earthquakes of a large area, from Albania to Caucasus. For each earthquake, a short summary of the main effects is supplied, together with the list of the sources used. Such information is intended as material for assessing location and size of the earthquakes, task that the author accomplished only in a very preliminary way for a few earthquakes, only. In addition to exhaustive descriptions of the most known earthquakes and the relevant historical sources, the volume contains information on a large number of earthquakes, so far unknown to the current earthquake catalogues. This paper intends to represent a homage to his immense work, partially showing the potential of his volume. We briefly present here some case histories, including the preliminary location and size of the earthquakes – known and unknown—around Anatolia. We add some examples of how he was able to prove that some alleged earthquakes are actually to be considered as fake or very doubtful. We also present the damage information supplied for some known and unknown earthquakes, and how they can be used for assessing location and size of them.

Description: Published

Description: 555–568

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: N/A or not JCR

Description: We discuss two competing models for explaining the ground deformation associated with normal faulting earthquake in the brittle elastic upper crust. The classic elastic rebound theory is usually applied for all tectonic settings. In normal fault earthquakes, this model would predict a horizontal stretching eventually responsible for the elastic rebound at the earthquake. However, volumes mostly subside vertically during an extensional earthquake and the collapsed ground in the hanging wall is about one order of magnitude larger than the uplifted volumes of the surrounding hanging wall and footwall. The elastic rebound model would explain this asymmetry with a high horizontal elastic compressibility of the hanging wall and footwall absorbing the coseismic push. We rather suggest that the force activating normal fault earthquakes is mostly dictated by the sliding of the hanging wall, owing gravitational potential. The much larger coseismic subsidence with respect to the uplift can be explained by the closure at depth of a diffuse network of microfractures developed during the interseismic period. Since the horizontal stretching does not exist below ~1 km of depth, with the minimum horizontal stress tensor becoming positive below that depth, the development of a normal fault can be activated only by the vertical maximum stress tensor, i.e., the lithostatic load. The common fluids expulsion at the coseismic stage requires diffuse secondary permeability in the upper crust, in agreement with the presence of a diffuse network of microfractures.

Description: Published

Description: SE213

Description: 2T. Deformazione crostale attiva

Description: JCR Journal

Description: Third-generation gravitational wave observatories will extend the lower frequency limit of the observation band toward 2 Hz, where new sources of gravitational waves, in particular intermediate-mass black holes (IMBH), will be detected. In this frequency region, seismic noise will play an important role, mainly through the so-called Newtonian noise, i.e., the gravity-mediated coupling between ground motion and test mass displacements. The signal lifetime of such sources in the detector is of the order of tens of seconds. In order to determine whether a candidate site to host the Einstein Telescope observatory is particularly suitable to observe such sources, it is necessary to estimate the probability distributions that, in the characteristic time scale of the signal, the sensitivity of the detector is not perturbed by Newtonian noise. In this paper, a first analysis is presented, focused on the Sos Enattos site (Sardinia, Italy), a candidate to host the Einstein Telescope. Starting from a long data set of seismic noise, this distribution is evaluated considering both the presently designed triangular ET configuration and also the classical ”L” configuration.

Description: Published

Description: 511

Description: 2IT. Laboratori analitici e sperimentali

Description: JCR Journal