ALBERT

Description: probably confirm this opinion, with qualifica ons. Historical earthquake catalogues, up to CPTI11 [Rovida et al., 2011], report only one Mw 5.1 event on 13 November 1948: it was located in the Sardinian Sea, and had very modest effects on land. In later decades, the seismic networks did record very few earthquakes of moderate energy (Mw 〈5), mostly located off-shore, either south-east of Cagliari or west of Olbia or in the Sea of Sardinia. The most recent ones (occurred in 2000, 2004 and 2006) had very slight effects on the island. Given the low level of instrumental seismicity and the weak macroseismic effects of known historical earthquakes, Sardinia's seismic risk is perceived as very low. The low seismicity of the region certainly has a geological explana on, given that the Corsica-Sardinia block is among the most stable areas of the Mediterranean basin. “Low”, however, does not mean “non- existent”: recent historical research has improved knowledge on the major known historical earthquake of Sardinia (it occurred on June 4, 1616 and was responsible for minor but widespread damage to the system of coastal watchtowers, south-west of Cagliari) and rediscovered several minor earthquakes, part of which were known to the seismological tradi on but had been almost completely forgo en. This paper collects all the documenta on available at present on the seismic history of Sardinia.

Description: Published

Description: 1-160

Description: 4T. Sismicità dell'Italia

Description: JCR Journal

Description: Questo rapporto tecnico descrive le attività svolte da SISMIKO [Moretti et al., 2012; 2016a; 2016b; Pondrelli et al., 2016] in occasione della sequenza sismica che ha interessato l’area in provincia di Campobasso tra i comuni di Montecilfone, Guardialfiera e Larino a partire dal 14 agosto 2018 e che ha visto nel terremoto di magnitudo ML 5.2 (MW 5.1) del 16 agosto 2018 (18:19 UTC), ben risentito in un’ampia area che comprende molte regioni dell’Italia centro meridionale, l’evento più significativo della sequenza. SISMIKO è uno dei gruppi operativi dell’Istituto Nazionale di Geofisica e Vulcanologia (INGV) per la gestione delle emergenze sismiche [Pondrelli et al., 2016], e come per ogni terremoto con magnitudo superiore a 5.0, ovvero alla soglia prevista nella vigente Convenzione tra l’INGV e il Dipartimento della Protezione Civile (DPC), a seguito del terremoto del 16 agosto 2018 (ML 5.2) ha predisposto un intervento volto al miglioramento del monitoraggio sismico dell’area interessata. L’integrazione di stazioni sismiche temporanee nella geometria della Rete Sismica Nazionale (RSN [Michelini et al., 2016; INGV Seismological Data Centre]), consente infatti un miglioramento nella individuazione dei terremoti e un perfezionamento del calcolo dei parametri ipocentrali, soprattutto della profondità che è strettamente connessa alla distanza media tra le stazioni sismiche. L’intervento principale è stato svolto nella giornata del 17 agosto [SISMIKO working group, 2018], ma nelle due settimane successive i siti allestiti sono stati più volte visitati e il giorno 30 si è proceduto con l’integrazione di ulteriori 2 stazioni, portando a 5 i punti di acquisizione della rete temporanea. La rete sismica è stata operativa per circa 2 mesi. I dati sono stati trasmessi in tempo reale al centro di acquisizione dati della rete mobile presso la sede di Roma di SISMIKO e al contempo integrati nel sistema di sorveglianza sismica INGV [Michelini et al., 2016] per essere utilizzati nelle localizzazioni e nei prodotti scientifici forniti in tempo reale. On 16 August 2018 at 18:19:04 UTC an earthquake with magnitude ML 5.2 (MW 5.1) occurred in the Molise region. The earthquake was felt in a large area including many regions of Central and Southern Italy. The seismologists on duty in the 24H seismic monitoring room of the National Institute of Geophysics and Volcanology (INGV) located the event in the province of Campobasso, 4 km south­east of Montecilfone and at a preliminary depth of 9 km. The same area was affected two days before by a MW 4.6 event (August 14 at 23.48 Italian time1). Following the MW 5.1 event and the associated aftershock sequence, the SISMIKO Operational Group was activated [Moretti et al., 2012; 2016a; 2016b; Pondrelli et al., 2016] for the installation of temporary seismic stations to integrate the permanent stations of the National Seismic Network (RSN [Michelini et al., 2016; INGV Seismological Data Centre]) deployed in the region.

Description: Published

Description: 1-32

Description: 2SR TERREMOTI - Gestione delle emergenze sismiche e da maremoto

Description: N/A or not JCR

Description: Questa è una traduzione commentata del raro documento citato da oltre un secolo di bibliografia come “Milne, 1890”. Si è studiato il testo per verificare la realisticità di alcune recenti affermazioni sul fatto che questo rapporto (oggi difficilmente reperibile) avesse trattato per la prima volta di precursori elettromagnetici. Si è cercato di indagare su ogni episodio e personaggio, identificando i criptici (e a volte inesistenti) riferimenti bibliografici, rintracciando quasi tutti i testi, ampliando e commentando spesso le relative citazioni. La mia opinione è che nessuno all’epoca di Milne avesse consapevolmente, ma forse nemmeno accidentalmente, osservato un precursore di origine elettromagnetica. I fenomeni descritti sono studiati da un punto di vista puramente elettrico o magnetico. I segnali elettrici riguardano tensioni e correnti troppo alte. I fenomeni magnetici già all’epoca furono contestati come prodotti di effetti inerziali ma comunque è difficile pensare che la componente campo magnetico di un segnale EM possa deviare stabilmente l’ago di una bussola. Questa stessa ricerca ha tuttavia portato alla luce qualche altro caso sospetto che sarebbe opportuno indagare in modo più approfondito, in quanto potrebbe risultare realmente il primo caso documentabile dell’osservazione di un precursore elettromagnetico del terremoto.

Description: This is a commented translation of the rare document cited by more than a century of bibliography as "Milne, 1890". The text was studied to verify the veracity of some recent claims that this report (presently difficult to find) had dealt with electromagnetic precursors for the first time. An attempt was made to investigate each episode and character, identifying the cryptic (and sometimes non-existent) bibliographic references, tracing almost all the texts, often expanding and commenting on the relative citations. My opinion is that no one, at the time of Milne, had consciously, but maybe not even accidentally, observed a precursor of electromagnetic origin. The phenomena described are studied from either a purely electrical or magnetic point of view. Electrical signals concern too high voltages and currents. Magnetic phenomena, already at the time, were contested as products of inertial effects, but in any case it is difficult to think that the magnetic field component of an EM signal can permanently deflect the needle of a compass. However this same research has brought to light some other potentially interesting cases that should be investigated further. One of them, could actually be the first documentable case of the observation of an electromagnetic seismic precursor.

Description: Progetto INGV “Pianeta Dinamico” (codice progetto INGV 1020.010) finanziato dal MIUR ("Fondo finalizzato al rilancio degli investimenti delle amministrazioni centrali dello Stato e allo sviluppo del Paese", legge 145/2018).

Description: Published

Description: 1-48

Description: 2TM. Divulgazione Scientifica

Description: JCR Journal

Description: A seguito di un evento sismico al di sopra della soglia del danno, una parte del personale dell’Istituto Nazionale di Geofisica e Vulcanologia (INGV) viene coinvolto nei gruppi di emergenza e si prepara, nel più breve tempo possibile, a partire per raggiungere l’area epicentrale. Ogni gruppo ha il compito di raccogliere dati, effettuare misurazioni e rilievi, per studiare il terremoto sotto diversi punti di vista, e per supportare le attività di Protezione Civile. In questo contesto rientrano le attività di rilievo del gruppo QUEST (QUick Earthquake Survey Team), formato da personale specializzato nel rilievo macrosismico dell’INGV e altri enti, che ha il compito di raggiungere le aree colpite dal sisma per fornire un rilievo degli effetti sull’edificato, sull’ambiente e sulle persone. L’indagine macrosismica che ne deriva, contribuisce allo studio del terremoto attraverso l’osservazione diretta e la classificazione del danno mediante l’utilizzo della scala macrosismica EMS98 [Grünthal, 1998]. Attualmente questa indagine viene svolta con l’ausilio di schede cartacee predisposte per la raccolta del dato ed una serie di mappe, generalmente immagini da satellite, delle località da investigare [Tertulliani et al., 2010]. Nel tempo si è cercato di studiare tecniche di rilievo sempre più rapide al fine di raccogliere il dato reale del danneggiamento prima che gli inevitabili interventi di messa in sicurezza dei vigili del fuoco o ulteriori repliche dannose modifichino lo scenario del danno sull’edificato. Per questo scopo si sta mettendo a punto uno strumento per la raccolta del dato macrosismico di campagna, basato sull’utilizzo di tablets, corredati di una interfaccia grafica tale da permettere la raccolta delle informazioni direttamente su mappe delle località da investigare. In particolare, l’inserimento dell’informazione puntuale per ogni edificio investigato, con il relativo dato di vulnerabilità e grado di danno, permette di condividere le informazioni in tempo reale tra le varie squadre sul terreno. Tale strumento permette inoltre, all’operatore, di lavorare off line e quindi di poter acquisire informazioni anche in assenza di copertura del segnale telefonico e di inviare in un secondo momento i dati. L’informazione viene centralizzata presso la sede operativa che può gestire e coordinare lo spostamento delle squadre nell’area epicentrale. In questo modo si aprono nuovi interessanti scenari sia a vantaggio della rapidità e della conoscenza del danneggiamento dell’edificato, sia in termini di gestione del personale coinvolto per ottimizzare così le operazioni di rilievo.

Description: Published

Description: 1-24

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

Description: N/A or not JCR

Description: Mobile network routers in seismic and volcanic surveillance

Description: Published

Description: 1-36

Description: 1IT. Reti di monitoraggio e sorveglianza

Description: N/A or not JCR

Description: “Move, protect, secure” were the three key points that the KnowRISK (Know your city, Reduce seISmic risK through non-structural elements) project posed at the core of its communication and dissemination strategy. This three key points enable each person, professional or not, to reduce non-structural damage caused by earthquakes. Dissemination is usually the last but never the least step of a communication plan, and indeed it played a crucial role in KnowRISK project for conveying the three key-point message to the widest audience. Standard dissemination activities, such as open-door events, and internet allowed us to achieve a wide spreading of ideas and best practices, reaching more than 4,000 non-professionals and almost 50,000 page views of the KnowRISK project website (in three years), respectively. As communication was recipient-targeted, the dissemination task of the project was addressed to professionals, layman, and schools. In particular, schools were chosen in order to profit from the chain-reaction action that is capable to spread a message from students to the surrounding environment.

Description: This study was co-financed by the European Commission’s Humanitarian Aid and Civil Protection through the European project KnowRISK (Know your city, Reduce seISmic risK through non-structural elements; Grant agreement ECHO/SUB/2015/718655/PREV28).

Description: Published

Description: SE328

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

Description: JCR Journal

Description: The Western Ionian Sea is characterised by an active and diffuse seismicity, directly related to the convergence of the European and African Plates and by gravitational sinking and rollback of the oceanic lithosphere. In this area, the location of earthquakes is characterised by considerable uncertainties due to large azimuthal gaps, resulting in notable location errors. This problem was partially overcome with the use of data recorded by NEMO-SN1 seafloor observatory (October 2002 - February 2003; June 2012 - May 2013). We relocated 1130 crustal and sub-crustal earthquakes using land network and NEMO-SN1 data. As most events occurred on Mt. Etna, we focused on 358 earthquakes in the offshore area and near the coasts of Sicily and Calabria. The use of the combined land-marine networks has improved the earthquake locations in terms of azimuthal GAP, as well as in horizontal and vertical errors. The comparison between locations performed with and without NEMO-SN1 data shows that differences in latitude, longitude and depths are more evident in the Western Ionian Sea and in the coast of Sicily, where values of the differences over 5 km correspond to structural heterogeneities. The increased number of seismic stations deployed on land from 2003 to 2012 did not influence the location of events occurring offshore, where NEMO-SN1 continued to be the distinctive tool in the location process. Moreover, the new 73 focal mechanisms computed with P-wave polarities from NEMO-SN1 and land stations are in agreement with the regional structural model, showing a prevalent normal, normal/oblique, and strike-slip kinematics. The similarity of two new focal solutions with the mechanisms of the main shock and aftershock of the 1990 earthquake demonstrates that the seismic structures are still active and potentially dangerous. The P-wave travel time residual analysis confirms the activity along the main structural alignments. A single point of observation in the Ionian Sea can significantly improve the quality of locations, giving an opportunity to focus on the seismogenic structures responsible for the occurrence of medium-to-high magnitude earthquakes.

Description: Published

Description: Se655

Description: 1T. Struttura della Terra

Description: JCR Journal

Description: Seismic event detection and phase picking are the base of many seismological workflows. In recent years, several publications demonstrated that deep learning approaches significantly outperform classical approaches, achieving human-like performance under certain circumstances. However, as studies differ in the datasets and evaluation tasks, it is unclear how the different approaches compare to each other. Furthermore, there are no systematic studies about model performance in cross-domain scenarios, that is, when applied to data with different characteristics. Here, we address these questions by conducting a large-scale benchmark. We compare six previously published deep learning models on eight data sets covering local to teleseismic distances and on three tasks: event detection, phase identification and onset time picking. Furthermore, we compare the results to a classical Baer-Kradolfer picker. Overall, we observe the best performance for EQTransformer, GPD and PhaseNet, with a small advantage for EQTransformer on teleseismic data. Furthermore, we conduct a cross-domain study, analyzing model performance on data sets they were not trained on. We show that trained models can be transferred between regions with only mild performance degradation, but models trained on regional data do not transfer well to teleseismic data. As deep learning for detection and picking is a rapidly evolving field, we ensured extensibility of our benchmark by building our code on standardized frameworks and making it openly accessible. This allows model developers to easily evaluate new models or performance on new data sets. Furthermore, we make all trained models available through the SeisBench framework, giving end-users an easy way to apply these models.

Description: This work was supported by the Helmholtz Association Initiative and Networking Fund on the HAICORE@KIT partition. J. Münchmeyer acknowledges the support of the Helmholtz Einstein International Berlin Research School in Data Science (HEIBRiDS). The authors thank the Impuls-und Vernetzungsfonds of the HGF to support the REPORT-DL project under the grant agreement ZT-I-PF-5-53. This work was also partially supported by the project 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.” Open access funding enabled and organized by Projekt DEAL.

Description: Published

Description: e2021JB023499

Description: 3T. Fisica dei terremoti e Sorgente Sismica

Description: JCR Journal

Description: The present paper describes the process of moving from a research study of most common vulnerable non-structural elements, to deliver solutions, tools and guidelines to improve understanding of and responsiveness to community concerns about seismic risk and non-structural elements. The observed damage to non-structural elements following recent earthquakes in Italy, Portugal and Iceland, were used for designing communication tools under the KnowRISK EU project for multi-stakeholders (students, business and citizens): the Practical Guide, the Students Short Guide, the KnowRISK Portfolio of Solutions, the Move, Protect and Secure video, the augmented reality apps, the maquettes, the students notebooks, videos, board games and hands-on tools. The philosophy behind these deliverables is that some risks, once identified, can be eliminated or reduced by informing people and suggesting preventive or emergency measures. These tools are devoted to improving the seismic performance of non-structural elements and to reduce the associated economic losses, loss of functionality, and potential threats to life safety. The rationale behind the selection of the information that people need to know for converting knowledge to more safety is discussed and a description of the transference of the findings of research to communication solutions is presented. The tools were planned following the engagement-model in risk communication to ensure that needs of communities and selected stakeholders were acknowledged, and that recipients are addressed in a way that appeals to them. Different media and communication channels such as print, television, online, face-to face communication and interviews were used for risk communication.

Description: This study was co-financed by the European Commission’s Humanitarian Aid and Civil Protection (Grant agreement ECHO/SUB/2015/718655/PREV28).

Description: Published

Description: SE322

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

Description: JCR Journal

Description: The SW Iberian margin is one of the most seismogenic and tsunamigenic areas in W-Europe, where large historical and instrumental destructive events occurred. To evaluate the sensitivity of the tsunami impact on the coast of SW Iberia and NW Morocco to the fault geometry and slip distribution for local earthquakes, we carried out a set of tsunami simulations considering some of the main known active crustal faults in the region: the Gorringe Bank (GBF), Marquês de Pombal (MPF), Horseshoe (HF), North Coral Patch (NCPF) and South Coral Patch (SCPF) thrust faults, and the Lineament South strike-slip fault. We started by considering for all of them relatively simple planar faults featuring with uniform slip distribution; we then used a more complex 3D fault geometry for the faults constrained with a large 2D multichannel seismic dataset (MPF, HF, NCPF, and SCPF); and finally, we used various heterogeneous slip distributions for the HF. Our results show that using more complex 3D fault geometries and slip distributions, the peak wave height at the coastline can double compared to simpler tsunami source scenarios from planar fault geometries. Existing tsunami hazard models in the region use homogeneous slip distributions on planar faults as initial conditions for tsunami simulations and therefore underestimate tsunami hazard. Complex 3D fault geometries and non-uniform slip distribution should be considered in future tsunami hazard updates. The tsunami simulations also support the finding that submarine canyons attenuate the wave height reaching the coastline, while submarine ridges and shallow shelves have the opposite effect.

Description: Published

Description: e2021JB022127

Description: 2T. Deformazione crostale attiva

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

Description: 2TR. Ricostruzione e modellazione della struttura crostale

Description: 2IT. Laboratori analitici e sperimentali

Description: JCR Journal

Description: The Italian earthquake waveform data are collected here in a dataset suited for machine learning analysis (ML) applications. The dataset consists of nearly 1.2 million three-component (3C) waveform traces from about 50 000 earthquakes and more than 130 000 noise 3C waveform traces, for a total of about 43 000 h of data and an average of 21 3C traces provided per event. The earthquake list is based on the Italian Seismic Bulletin (http://terremoti.ingv.it/bsi, last access: 15 February 2020​​​​​​​) of the Istituto Nazionale di Geofisica e Vulcanologia between January 2005 and January 2020, and it includes events in the magnitude range between 0.0 and 6.5. The waveform data have been recorded primarily by the Italian National Seismic Network (network code IV) and include both weak- (HH, EH channels) and strong-motion (HN channels) recordings. All the waveform traces have a length of 120 s, are sampled at 100 Hz, and are provided both in counts and ground motion physical units after deconvolution of the instrument transfer functions. The waveform dataset is accompanied by metadata consisting of more than 100 parameters providing comprehensive information on the earthquake source, the recording stations, the trace features, and other derived quantities. This rich set of metadata allows the users to target the data selection for their own purposes. Much of these metadata can be used as labels in ML analysis or for other studies. The dataset, assembled in HDF5 format, is available at http://doi.org/10.13127/instance (Michelini et al., 2021).

Description: Published

Description: 5509–5544

Description: 4T. Sismicità dell'Italia

Description: JCR Journal

Description: This text is an introduction to the problem of low frequency electromagnetic monitoring, with particular emphasis on VLF band. All related issues have been addressed: from historical outlook to numerical analysis, from seismology to geotechnics, electronics, information technology. The approach is informative and didactic. This interdisciplinary approach does not imply a problem of skills to the reader, and my goal has been to complete each specific cultural background. Geophysics is a topic where different training paths converge, usually geological or physical. In this case, addressing also technical aspectcts, it is not really possible to setup a guide for a specific professional figure. For this reason, while some topics will be new, others instead will inevitably seem trivial or superficially addressed. The reality is that every topic, as far as possible, has been treated on the same level. When necessary, an appendix to the text will offer further specific insights from time to time.

Description: Questo testo vuole essere un’introduzione alle problematiche del monitoraggio elettromagnetico a bassa frequenza, con particolare approfondimento sulla banda VLF. Vengono affrontate tutte le tematiche correlate, dall’analisi storica all’analisi numerica, dalla sismologia alla geotecnica, all’elettronica, all’informatica. L’impostazione è divulgativa e didattica. L’approccio interdisciplinare non porrà al lettore un problema di competenze, anzi l’obiettivo è quello di completare ogni specifico bagaglio culturale. La geofisica è già un argomento in cui convergono percorsi formativi diversi, solitamente di impostazione geologica o fisica. In questo caso, in cui si affronta anche un aspetto tecnico, non è proprio possibile indirizzare una guida a una specifica figura professionale. Per questo motivo, mentre alcuni argomenti risulteranno nuovi, altri inevitabilmente appariranno scontati o forse affrontati superficialmente. La realtà è che ogni tematica, per quanto possibile, è stata affrontata allo stesso livello. All’occorrenza, un’appendice offrirà di volta in volta ulteriori approfondimenti specifici.

Description: Progetto INGV “Pianeta Dinamico” (codice progetto INGV 1020.010) finanziato dal MIUR ("Fondo finalizzato al rilancio degli investimenti delle amministrazioni centrali dello Stato e allo sviluppo del Paese", legge 145/2018).

Description: Published

Description: 1-142

Description: 7T. Variazioni delle caratteristiche crostali e "precursori"

Description: N/A or not JCR

Description: We present here the results of a five-years-long earthquake educational project aiming to commemorate the hundredth anniversaries of five large Northern Apennines earthquakes occurred between 1916 and 1920 in the areas of: Rimini (1916, Mw 6.1), Valtiberina (1917, Mw 5.9), Romagna Apennines (1918, Mw 5.9), Mugello (1919, Mw 6.3) and Garfagnana (1920, Mw 6.5) earthquakes. We saw these anniversaries as the occasion for leading the Northern Apennines people to rediscover their past, in a positive way, and to improve their awareness of the earthquake as a natural feature of the regions in which they live. The activities that we planned for schools students encouraged them to go hunting for traces of the earthquakes of one hundred years ago in their home towns and to rediscover the memories and traditions of their communities. Together with their teachers, we also led the teenagers to find creative ways to involve the grownups in the process of discovery and knowledge. The Project had to cope with two emergencies: the great Central Italy earthquake of 2016-2017 and the Covid-19 epidemic. However, these stumbling blocks did not deter teachers and students from taking part in the process actively and even enthusiastically. Their families and communities were actively involved too. This experience taught us some valuable lessons. First of all, we learned to adapt the project, as we had conceived it at the start, to a wide gamma of social and cultural contexts. Not all the involved communities were equally aware of the level of seismic risk they are exposed to. On the affluent Adriatic coast, where tourism is the main source of income, past earthquakes are something best forgotten, by citizens and administrators alike. On the contrary, in the poorer inland mountain areas (Forlivese Apennines, Mugello, Garfagnana and Lunigiana) a more down-to-earth attitude prevails: earthquakes are looked upon as something that can and does happen and people are quick to grasp how important it is to contribute to initiatives whose aim is reducing seismic risk. Thus, we had to adapt our approach to the different contexts, modifying each time the activities we proposed to the schools with the aim of obtain the best possible results from each situation. Presentiamo i risultati di un progetto di educazione al rischio sismico attivato in occasione dei centenari di cinque terremoti storici che hanno colpito l’Appennino settentrionale tra gli anni 1916 e 1920 e precisamente i terremoti di Rimini 1916 (Mw 6.1), Valtiberina 1917 (Mw 5.9), Appennino romagnolo 1918 (Mw 5.9), Mugello 1919 (Mw 6.3) e Garfagnana 1920 (Mw 6.5). Abbiamo pensato di utilizzare questi anniversari come punto di partenza per accompagnare i cittadini a riappropriarsi del loro passato in modo positivo, facendo crescere la loro consapevolezza del terremoto come un carattere del loro ambiente naturale. A tal fine, nelle attività realizzate con le scuole, abbiamo incoraggiato gli studenti a cercare le tracce dei terremoti di un secolo fa nell’ambiente urbanizzato e a indagare le memorie e le tradizioni ancora presenti nelle comunità. Insieme ai loro insegnanti abbiamo spinto i ragazzi a trovare modi creativi per coinvolgere gli adulti in questo processo di scoperta e conoscenza. Il progetto è stato messo alla prova dal forte terremoto dell’Italia centrale (2016­2017) e dall’epidemia di Covid­19, ma nonostante queste difficoltà insegnanti e studenti hanno partecipato con grande interesse a questo percorso e hanno coinvolto nelle attività del progetto le famiglie e le comunità locali. Anche noi abbiamo imparato nuove lezioni. Un aspetto importante che abbiamo appreso è il bisogno di adattare il progetto a contesti sociali e culturali che si sono rivelati molto diversi. Le comunità coinvolte non condividono lo stesso livello di consapevolezza del rischio: sulla costa adriatica, a vocazione turistica, i terremoti sono qualcosa che è meglio dimenticare, sia da parte dei cittadini che dalle amministrazioni. Al contrario, nell’Appennino forlivese, nel Mugello, in Garfagnana e Lunigiana, i terremoti sono una presenza costante e le persone si sono sentite subito coinvolte in un processo attivo di riduzione del rischio e di attenzione quotidiana. Questo ci ha spinto ad adattare ogni volta l’approccio ai diversi contesti, modificando le proposte di attività che abbiamo realizzato nelle scuole.

Description: Lavoro realizzato nell’ambito della Convenzione fra INGV e Dipartimento della Protezione Civile, Allegato A, tematica “M”.

Description: Published

Description: 1-40

Description: 5SR TERREMOTI - Convenzioni derivanti dall'Accordo Quadro decennale INGV-DPC

Description: JCR Journal

Description: We present the first three-dimensional (3D) anisotropic teleseismic P-wave tomography model of the upper mantle covering the entire Central Mediterranean. Compared to isotropic tomography, it is found that including the magnitude, azimuth, and, importantly, dip of seismic anisotropy in our inversions simplifies isotropic heterogeneity by reducing the magnitude of slow anomalies while yielding anisotropy patterns that are consistent with regional tectonics. The isotropic component of our preferred tomography model is dominated by numerous fast anomalies associated with retreating, stagnant, and detached slab segments. In contrast, relatively slower mantle structure is related to slab windows and the opening of back-arc basins. To better understand the complexities in slab geometry and their relationship to surface geological phenomenon, we present a 3D reconstruction of the main Central Mediterranean slabs down to 700 km based on our anisotropic model. P-wave seismic anisotropy is widespread in the Central Mediterranean upper mantle and is strongest at 200-300 km depth. The anisotropy patterns are interpreted as the result of asthenospheric material flowing primarily horizontally around the main slabs in response to pressure exerted by their mid-to-late Cenezoic horizontal motion, while sub-vertical anisotropy possibly reflects asthenospheric entrainment by descending lithosphere. Our results highlight the importance of anisotropic P-wave imaging for better constraining regional upper mantle geodynamics.

Description: This study is supported by the ERC StG 758199 NEWTON.

Description: Published

Description: e2021JB023488

Description: 1T. Struttura della Terra

Description: JCR Journal

Description: The complex tectonic setting of the central-western Mediterranean has interested geoscientists for decades, but its geodynamic evolution remains a matter of debate. We rely on 807 seismometers from southern Europe and northern Africa to measure Rayleigh and Love phase velocities in the period range ∼5–200 s, based on teleseismic earthquakes and seismic ambient noise. By nonlinear joint inversion of the phase-velocity maps, we obtain a 3-D shear-wave velocity (VS) model of the study area. At shallow depths, our model correlates with surface geology and reveals the presence of a sedimentary cover in the Liguro-Provençal basin, as opposed to the Tyrrhenian basin where this is either very thin or absent. At ∼5-km depth, high velocities below the Magnaghi, Vavilov, and Marsili seamounts point to an exhumed, scarcely serpentinized mantle. These are replaced by lower velocities at larger depths, likely connected to the presence of partial melt. At 50–60-km depth, a very heterogeneous structure characterizes the Tyrrhenian basin, with low velocities pointing to the presence of fluids due to the lateral mantle inflow from the Ionian slab edges, and higher velocities associated with a relatively dry upper mantle. Such heterogeneity disappears at depths ≳75 km, replaced by more uniform velocities which are ∼2% lower than those found in the Liguro-Provençal basin. We infer that, at the same depths, the Tyrrhenian basin is characterized by a larger concentration of fluids and possibly higher temperatures.

Description: The Grant to the Department of Science, Roma Tre University (MIUR-Italy Dipartimenti di Eccellenza, ARTICOLO 1, COMMI 314-337 LEGGE 232/2016) German Academic Exchange Service (DAAD, Grant 57030312). Projekt DEAL. Funded by the Deutsche Forschungsgemeinschaft (DFG - German Research Foundation) under the Individual Research Project: SI 1748/4-1.

Description: Published

Description: e2021JB023267

Description: 1T. Struttura della Terra

Description: JCR Journal

Description: This work was carried out within the 2015 ART-IT project (Early Earthquake Alert in ITaly). Its main purpose is to investigate the performance and the critical issues of an early warning system with particular reference to the PRESTo system (PRobabilistic and Evolutionary early warning SysTem, [Iannacone et al., 2010; Satriano et al., 2011]) whose use has been tested in the framework of the above mentioned project. The correct operation of an early warning system can effectively guarantee a more effective management of a seismic emergency from the first seconds after the occurrence of a strong earthquake, allowing quick actions to reduce exposure and seismic risk. The work was substantially subdivided into two main steps. A first calibration phase, carried out in the first part of the project and aimed to identify the best values of the software configuration parameters in terms of event triggering and declaration. Once the values of the aforementioned parameters have been identified, the second phase of the work was focused on testing the software in real time configuration, on a test site area and the subsequent evaluation of its performance in terms of declaration and localization capacity. This work focuses mainly on the second part of the experimentation and is aimed describing and summarizing the analysis carried out to evaluate the response of the PRESTo software (and in general of an early warning system) after one year of experimentation and acquisition and highlight any problems and critical issues of the software and more generally of the rapid alert systems.

Description: Published

Description: 1-32

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

Description: JCR Journal

Description: The prompt identification of faults responsible for moderate-to-large earthquakes is fundamental for understanding the likelihood of further, potentially damaging events. This is increasingly challenging when the activated fault is an offshore buried thrust, where neither coseismic surface ruptures nor GPS/InSAR deformation data are available after an earthquake. We show that on 9 November 2022, an Mw 5.5 earthquake offshore Pesaro ruptured a portion of the buried Northern Apennines thrust front (the Cornelia thrust system [CTS]). By post-processing and interpreting the seismic reflection profiles crossing this thrust system, we determined that the activated fault (CTS) is an arcuate 30-km-long, NW-SE striking, SW dipping thrust and that older structures at its footwall possibly influenced its position and geometry. The activation of adjacent segments of the thrust system is a plausible scenario that deserves to be further investigated to understand the full earthquake potential of this offshore seismogenic source.

Description: Published

Description: e2022GL102299

Description: 4T. Sismicità dell'Italia

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

Description: 2TR. Ricostruzione e modellazione della struttura crostale

Description: 2IT. Laboratori analitici e sperimentali

Description: JCR Journal

Description: This simple and qualitative discussion is an attempt to include in a comprehensive framework the problem of earthquake forecasting and univocally clarify the meaning of "precursor" and the true importance of their study. It is also the starting point to present the potential of the electromagnetic precursor in the framework of classic precursors. The fact that seismic precursors are truly existing phenomena does not represent the solution to the problem of deterministic forecasting. Currently a precursor is not a prediction aid but an investigative tool of the earthquake preparation process: aka the complex mechanism of microfracturing, growth and self-organization of fractures that is necessary to produce ruptures in the crust. Scholz's "Theory of Dilatance" (ToD), improved and further developed for decades after 1960, remains one of the best explanations for the existence of observable precursors and still seems to highlight the only plausible common cause. ToD is presented here in an "extended" vision in the framework of geotechnical knowledge on rock fracturing in the laboratory. Dilatance is a systematic and necessary process with respect to rock breaking. It would itself be the ideal precursor to the earthquake if it did not lack the essential characteristic of being directly observable. At the moment, the only way to detect dilatance in nature is through its interaction with the surrounding environment and its ability to change the physical characteristics of the rock, that is, through secondary phenomena that it can cause. These phenomena sometimes visible on the surface are what we call precursors. We have reviewed the main "classic" precursors by examining them in the light of the ToD. The study of dilatance, which requires a comparative, systematic and extensive monitoring of precursor phenomena, could lead to a key of interpretation of the precursors themselves for the prediction of the earthquake.

Description: Questa trattazione divulgativa è un tentativo di presentare il problema della previsione dei terremoti nella sua globalità per chiarire il significato di “precursore” e la vera utilità dello studio dei precursori. È anche lo spunto per presentare al pubblico le potenzialità del precursore elettromagnetico nel panorama dei precursori classici. Il fatto che i precursori sismici siano fenomeni realmente esistenti non rappresenta la soluzione al problema della previsione deterministica. Attualmente un precursore non è uno strumento di previsione ma un mezzo di sondaggio di ciò che chiamiamo “preparazione del sisma”: il complesso meccanismo di microfratturazione, accrescimento e autoorganizzazione delle fratture che è necessario a produrre la rottura nella crosta. La “teoria della Dilatanza” (TdD) di Scholz, più volte perfezionata dal 1960 ad oggi, resta una delle migliori trattazioni invocabili per motivare l’esistenza dei precursori documentati e sembra tuttora restare l’unica plausibile forma di inquadramento comune. Essa viene qui ripresentata in una visione “estesa” alla luce delle conoscenze geotecniche sulla fratturazione della roccia in laboratorio. La dilatanza è un processo sistematico e necessario rispetto alla rottura della roccia. Sarebbe essa stessa il precursore ideale del terremoto se non mancasse della caratteristica essenziale di essere visibile. Al momento l’unico modo per rilevare la dilatanza in natura è attraverso la sua interazione con l’ambiente circostante e la sua capacità di mutare le caratteristiche fisiche della roccia, cioè attraverso fenomeni secondari che essa può causare. Questi fenomeni, talvolta visibili in superficie, sono ciò che chiamiamo precursori. Abbiamo messo in rassegna i principali precursori “classici” esaminandoli alla luce della TdD. Lo studio della dilatanza, che richiede un monitoraggio comparato, sistematico ed esteso dei fenomeni precursori, potrebbe condurre alla definizione di una chiave interpretativa comune e generale dei precursori stessi per la previsione del terremoto.

Description: Progetto INGV “Pianeta Dinamico” (codice progetto INGV 1020.010) finanziato dal MIUR ("Fondo finalizzato al rilancio degli investimenti delle amministrazioni centrali dello Stato e allo sviluppo del Paese", legge 145/2018).

Description: Published

Description: 1-40

Description: 7T. Variazioni delle caratteristiche crostali e "precursori"

Description: JCR Journal

Description: In Italy, historical research on earthquakes has a long and glorious tradition, which in recent decades has gone through very different phases. In the first half of the 1980s and up to the mid- 90s, two very demanding research ventures were developed: the research program financed by ENEL for the qualification of sites susceptible to nuclear plants in three areas of the country (Piedmont, Lombardy, Puglia), later merged into the “Catalog of Strong Italian Earthquakes” (CFTI) of the ING/INGV, and the “Hazard project” of the GNDT/CNR, aimed at preparing all the basic data necessary for a model of hazard updated. As part of these two ventures, for about a decade over a hundred researchers, mostly “professional” historians, have worked to update their knowledge of Italian historical earthquakes. Researches developed by the “Hazard Project” - complementary to those of the CFTI - aimed only at rapidly re-evaluating the knowledge on about 600 intermediate energy earthquakes. Some of these studies, after a couple of decades, are now largely obsolete. For this reason, a work plan was launched aimed at deepening the knowledge on several dozens of these studies, marked in the current Parametric Catalog of Italian Earthquakes (CPTI15) by the initials AMGNDT95, providing them with an updated and, hopefully, better database. This work presents the results of research carried out on 6 earthquakes included in the 1949– 1971 time span. Such researches have allowed a significant improvement of the epicentral parameters of these earthquakes and, at the same time, an enhancement of seismic histories of numerous localities.

Description: Lavoro realizzato nell’ambito della Convenzione fra INGV e Dipartimento nazionale della Protezione Civile, Allegato B2.

Description: Published

Description: 1-274

Description: 4T. Sismicità dell'Italia

Description: JCR Journal

Description: We analyzed 12 years of continuous seismic data acquired by two seismic stations in Central Apennines (Italy) with the aim to investigate the temporal variations of H/V spectral ratios. The two stations are located in the epicentral areas of the main strong motion earthquakes occurred in Central Italy in the last 12 years (L’Aquila 06 April 2009, Mw 6.1; Amatrice 24 August 2016, Mw 6.0; Visso 26 October 2016, Mw 5.9, and Norcia 30 October 2016, Mw 6.5). H/V ratios are computed both on continuous and earthquakes data recorded by the two stations. H/V ratios are subjected to abrupt changes after strong earthquakes. The results highlight that after strong shaking, there are remarkable drops of the peak frequencies (7%–10% of reduction). After this sudden decrease, the peak frequency slowly recovers to the initial value in a time ranging from a few months to a few years. We also observe a moderate frequency variation (of order of 2%–3%) linked to seasonal variations: the peak frequencies increase in the spring-summer months and decrease during the winter. The frequency changes after strong earthquakes have been interpreted in terms of velocity variations of the shallow layers. This effect must be taken into account for microzonation, geophysical, and engineering studies that are often carried out in the epicentral areas after strong earthquakes. H/V analysis over time proved to be a useful procedure for highlighting temporal changes relating to the properties of shallow layers of the propagation medium and could provide relevant information for the site characterization of permanent seismic stations.

Description: Published

Description: e2021JB023848

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

Description: JCR Journal

Description: This report describes the state of the art of the installation techniques for seismic stations developed by the Seismology Group and the Seismology Laboratory at the INGV branch in Pisa, with examples of applications taken from long‐duration field experiments carried out in different areas of Tuscany, such as Monte Amiata and the Mugello basin. Our goal was to develop a low‐cost infrastructure, portable and easily adaptable to different terrains, suitable for hosting a variety of real‐time seismic stations. In addition to improving the structural resistance of the deployment, we also developed applications for the remote monitoring of the state of health of the seismic stations, which allowed a more efficient maintenance of the instrumentation. The proposed type of installation has proved to be sufficiently robust and suitable for installations with a temporal duration of a few years, and in agreement with the expected targets, as proved by the analyses carried out during and at the end of the experiments in which they were used.

Description: Published

Description: 1-30

Description: 1IT. Reti di monitoraggio e sorveglianza

Description: N/A or not JCR

Description: Exist­-fdsn-­station is an open source software that implements the standard fdsnws/station web service, integrating the application into a native XML database containing seismic stations metadata in the StationXML file format. Through its HTTP Application Programming Interface, extended with the PUT method for writing, this software can be used as a RESTful microservice. The software is publicly available and licensed under a General Public License. This manual describes all the operational phases, from installation to distribution in a production environment, for using exist-­fdsn-­station to store a set of StationXML files and exposing them efficiently with a standard fdsnws/station webservice.

Description: Published

Description: 1-28

Description: OST5 Verso un nuovo Monitoraggio

Description: N/A or not JCR

Description: Nel 2018 è stato avviato il progetto FOCUS - Fiber Optic Cable Use For Seafloor Studies Of Earthquake - coordinato da Marc-André Gutscher del Laboratoire Géosciences Océan dell’Università di Brest, in Francia. Questo progetto indaga la sismicità e la struttura crostale del Mar Ionio attraverso l’analisi e l’interpretazione di dati raccolti da strumentazione sottomarina e da reti di monitoraggio disponibili o appositamente installate nelle zone di costa. In tale contesto, l’Osservatorio Nazionale Terremoti (ONT) e l’Osservatorio Etneo (OE), entrambe Sezioni dell’Istituto Nazionale di Geofisica e Vulcanologia (INGV), e il Laboratorio di Sismologia dell'Università della Calabria (UniCal), hanno contribuito al progetto con l’installazione di una rete sismica temporanea lungo la costa ionica calabro-siciliana a integrazione della rete permanente presente nell’area dello Stretto di Messina. La rete temporanea, costituita da 13 stazioni, ha acquisito dal mese di dicembre 2021 al mese di giugno 2023. Nel gennaio 2022, i partner internazionali del progetto FOCUS hanno installato una rete temporanea di sismometri OBS e sensori di pressione per fondali marini. La grande quantità di dati raccolta e la loro integrazione, consentirà di migliorare il monitoraggio sismico e le conoscenze relative alla struttura terrestre dell’area con particolare attenzione alle strutture sismogenetiche con un dettaglio mai raggiunto fino a ora. Tutte le istituzioni coinvolte in FOCUS collaborano per l’acquisizione e l’elaborazione dei dati, l’imaging dell’interno della Terra attraverso l’utilizzo di tecniche avanzate, l’interpretazione e la modellazione dei dati. Il presente lavoro descrive la progettazione, la realizzazione e la gestione della rete temporanea a terra definita FXland, fornendo indicazioni relative sul suo generale funzionamento e sulle caratteristiche del dataset acquisito.

Description: Published

Description: 1-26

Description: OST1 Alla ricerca dei Motori Geodinamici

Description: OST3 Vicino alla faglia

Description: N/A or not JCR

Description: Over the years, seismic anisotropy characterization has become one of the most popular methods to study and understand the Earth’s deep structures. Starting from more than 20 years ago, considerable progress has been made to map the anisotropic structure beneath Italy and the Central Mediterranean area. In particular, several past and current international projects (such as RETREAT, CAT/SCAN, CIFALPS, CIFALPS-2, AlpArray) focused on retrieving the anisotropic structure beneath Italy and surrounding regions, promoting advances in the knowledge of geological and geodynamical setting of this intriguing area. All of these studies aimed at a better understanding the complex and active geodynamic evolution of both the active and remnant subduction systems characterising this region and the associated Apennines, Alps and Dinaric belts, together with the Adriatic and Tyrrhenian basins. The presence of dense high-quality seismic networks, permanently run by INGV and other institutions, and temporary seismic stations deployed in the framework of international projects, the improvements in data processing and the use of several and even more sophisticated methods proposed to quantify the anisotropy, allowed to collect a huge amount of anisotropic parameters. Here a collection of all measurements done on core refracted phases are shown and used as a measure of mantle deformation and interpreted into geodynamic models. Images of anisotropy identify well-developed mantle flows around the sinking European and Adriatic slabs, recognised by tomographic studies. Slab retreat and related mantle flow are interpreted as the main driving mechanism of the Central Mediterranean geodynamics.

Description: Published

Description: SE215

Description: OST1 Alla ricerca dei Motori Geodinamici

Description: JCR Journal

Description: We model Coulomb stress transfer (CST) due to 30 strong earthquakes occurring on normal faults since 1509 CE in Calabria, Italy, including the influence of interseismic loading, and compare the results to existing studies of stress interaction from the Central and Southern Apennines, Italy. The three normal fault systems have different geometries and long-term slip-rates. We investigate the extent to which stress transfer can influence the occurrence of future earthquakes and what factors may govern the variability in earthquake recurrence in different fault systems. The Calabrian, Central Apennines, and Southern Apennines fault systems have 91%, 73%, and 70% of faults with mean positive cumulative CST in the time considered; this is due to fewer faults across strike, more across strike stress reductions, and greater along-strike spacing in the three regions respectively. In regions with close along strike spacing or few faults across strike, such as Calabria and Southern Apennines, the stress loading history is mostly dominated by interseismic loading and most faults are positively stressed before an earthquake occur on them (96% of all faults that ruptured in Calabria; 94% of faults in Southern Apennines), and some of the strongest earthquakes occur on faults with the highest mean cumulative stress of all faults prior to the earthquake. In the Central Apennines, where across strike interactions are the predominant process, 79% of earthquakes occur on faults positively stressed. The results highlight that fault system geometry plays a central role in characterizing the stress evolution associated with earthquake recurrence.

Description: This work was supported by a Natural Environment Research Council studentship (Grant NE/L002485/1) to Claudia Sgambato. Original development of the 3D-faults code was supported by NERC PhD Studentship NE/L501700/1 and JSPS Short Term Fellowship PE15776 to Zoë Mildon.

Description: Published

Description: e2023JB026496

Description: OST2 Deformazione e Hazard sismico e da maremoto

Description: JCR Journal

Description: Nel mese di maggio 2022 è iniziato uno sciame sismico, di breve durata, che ha interessato una piccola area del Chianti fiorentino a circa 15 km a sud dalla città di Firenze. I due terremoti più energetici hanno avuto una magnitudo momento pari a 3.7; nonostante la magnitudo modesta, tali eventi sono stati avvertiti distintamente fino a distanze di diverse decine di chilometri, e hanno destato preoccupazione nella popolazione prossima all’area epicentrale. Inoltre, dato l’ingente patrimonio artistico presente nel capoluogo toscano, questo episodio ha sollevato interrogativi sulla sua vulnerabilità anche a scuotimenti del suolo di piccola entità. Al fine di migliorare le conoscenze sulla ubicazione e le dimensioni delle strutture sismogenetiche attive in prossimità di Firenze, l’Istituto Nazionale di Geofisica e Vulcanologia (INGV) è intervenuto nell’area interessata dallo sciame attraverso il Gruppo Operativo (GO) di emergenza SISMIKO. Il 4 maggio, giorno successivo all’inizio dello sciame, cinque stazioni sismiche mobili sono state installate a distanza ravvicinata dall’area epicentrale, e integrate nel sistema di monitoraggio permanente INGV. Questo lavoro descrive le procedure relative a: (i) l’installazione, la manutenzione e la disinstallazione della rete sismica mobile; (ii) la gestione e il controllo di qualità dei dati acquisiti. Infine, vengono presentate, in riferimento al contesto sismotettonico dell’area, le caratteristiche spaziali e l’evoluzione temporale dello sciame, che ha presentato una piccola ripresa nell’attività sismica ad agosto del 2022, con un terremoto di magnitudo locale 2.7 e successive repliche.

Description: Published

Description: 1-26

Description: OST5 Verso un nuovo Monitoraggio

Description: JCR Journal

Description: The latest version of the CPTI15 seismic catalogue (January 2022) includes more than two hundred earthquakes marked AMGNDT95. Their parameters are derived from expeditious studies produced as part of the GNDT/CNR ‘Hazard Project’ (1993-1995). Some of them simply parameterise data taken from bibliographic references in the PFG85 catalogue, i.e., mostly Mario Baratta’s seismological compilation “I terremoti d’Italia” [1901] or twentieth-century seismological bulletins. Others go back as far as the original sources of the references themselves. As part of the B2 Convention between INGV and DPC (2016-2021), a review of these earthquakes was initiated, starting with the most relevant ones, for which a good margin of improvement in knowledge can be assumed. At the same time, first-level research was also begun on a dozen or so earthquakes of low energy, but still above the damage threshold, which for various reasons had never been studied so far and whose parameters in the CPTI15 are still those of the POS85 catalogue. We present here the results of the study of about thirty earthquakes belonging to both categories. The overall result is generally a strong improvement of the available information, from which it will be possible to derive epicentral parameters more up-to-date and more robust than the previous ones.

Description: Questo lavoro è stato realizzato nell’ambito della Convenzione fra INGV e Dipartimento nazionale della Protezione Civile, Allegato B2.

Description: Published

Description: 1-260

Description: 4T. Sismicità dell'Italia

Description: JCR Journal

Description: The seismic monitoring of the national territory and of the EuroMediterranean area makes use of the velocimetric, accelerometric and GPS (geodetic) data acquired by the stations of the National Seismic Network, by the RING Network and by the MedNet Network. As part of the FISR 2017 project “Integrated operating rooms and monitoring networks for the future: INGV 2.0” (2017), sensors capable of detecting both geophysical and geochemical parameters at the same time are being integrated. This technical report describes the integration of a Rn222 sensor (radon hereafter). Over the past few decades radon has found a variety of Earth Science applications, ranging from its use as a potential earthquake precursor and tectonic stress indicator to its specific role in volcanic environments, where significant changes in concentration previous or concomitant to eruptive crises are also induced by volcanic gases, CO 2 for example, which act as carriers accelerating the migration of radon through the earth’s crust and therefore its detection. In order to explore the possibility of a link between seismogenic processes and temporal variability of radon emissions, a permanent national network has been created, IRON (Italian Radon mOnitoring Network), which uses both commercial radon instruments, equipped with a proprietary system for data storage, transmission and consultation, and INGV sensors that need an interface to acquire and make data available remotely. A hardware and software interface has therefore been designed, built and tested capable of i) counting and storing the pulses in TTL format generated by the instrument which measures the 8 radon concentration in air, ii) being connected to a router for sending the acquired data to a server. A service (syncproc) was also created in PHP to query remote stations at regular intervals and collect the acquired data intended to populate a database created with MariaDB. An expressly created website allows to extract the stored data from the database and configure each installed sensor. The various software elements have been designed using open source resources.

Description: Published

Description: 3-18

Description: OST5 Verso un nuovo Monitoraggio

Description: N/A or not JCR

Description: The “Giornata ONT 2023” arises from the will to let know within INGV how many activities do people from the Osservatorio Nazionale Terremoti (ONT), and how strong is their contribution to the INGV missions: Research, Services, Education, Communication. In the nearly seven years of the current management the ONT has experienced a continuous evolutionary, sometimes complex, path. But it is always a straight path to pursue the objective of a continuous growth of the ONT. During these years the ONT has changed its name (from Centro Nazionale Terremoti – CNT, to ONT); it has experienced the coming out of some employees that moved to create the Irpinia new Section; it has lived the novelty of incoming people (example from the Centro Allerta Tsunami). It has also faced the need to overcome the limitations due to the worldwide pandemic emergency COVID19, either for the h24 services or for the research activities. Therefore in 2020 and 2021 we have only remotely attended the ONT days. The drive to be “in presenza” comes from this latter issue. We strongly want to meet, to talk face to face, to “Welcome” the young colleagues who are the injection of new ideas and perspectives, that are the necessary fuel to evolve the knowledge. As a matter of fact it emerges from the DNA of the ONT, i.e. the inclusiveness and the multidisciplinarity. This latter is widely testified by the ONT activities that are shared among the three Departments and their strategic objectives. The agenda of the “Giornata ONT 2023” has specifically emphasized the variety of the technical and scientific contents, that for sake of simplicity have been collected in the following themes: • Infrastructures, Data­Sharing and Laboratories • Analysis, Modelling, Interpretation of Geophysical Phenomena • National and International Projects (Research Results and Products from Completed Projects; Ongoing Projects) • Society ­ Communication, Dissemination, Emergency Management • Seismic Surveillance And Tsunami Warning Overall, the contributions have been 100, most of which are posters (77) and the remaining (23) in different exhibit formats. The wide interest about the proposed contents and the positive feedback from the attendance, pushed the decision to collect and publish the contributions in a Miscellanea INGV, where the documents can be easily found. And we are finally ready to make the Miscellanea available to the reader. I would warmly thank the Authors for their enthusiastic acceptance to contribute, the Conveners of the “Giornata ONT 2023” Sessions for their availability to organise and manage the submitted poster/exhibits, the Editorial Board members for their hidden work that led to this Miscellanea. In conclusion, let me spend a few words about my personal journey as Director of the ONT. After 2504 days it has come to an end and the “Giornata ONT 2023” and the Miscellanea are, somehow, the cherry on top. It is really difficult to say “Thanks” one by one to the people who helped me along this complex and long path. So, please, let me simply say Grazie a tutti voi! Salvatore Stramondo - Director ONT (2017-2023)

Description: Published

Description: 1-206

Description: N/A or not JCR

Description: This paper is intended as a short presentation of the main limitations affecting seismic hazard assessment, revisiting possible methods available in the literature to be applied for this purpose. The convergence of the African Plate with the Eurasian Plate is the cause of the high seismic activity characterizing the Mediterranean region, with particular intensity in its eastern part. It is clear that the associated seismic risk requires appropriate measures for its mitigation. Seismic risk, the amount of resources that the community is expected to pay to earthquakes in the long term, is the product of three factors, such as seismic hazard, vulnerability and value of the exposed goods. As earthquakes cannot be prevented, seismic risk can be mitigated by improving our knowledge of seismic hazard, which is largely based on statistical analysis of historical earthquake catalogs. Nevertheless, historical records are affected by problems of reliability, completeness and shortness, as they commonly span time lengths of the same order of magnitude or even shorter than the inter-event time of the strongest earthquakes produced by specific seismic sources. In this respect, alternative methods can be proposed for integrating and improving our knowledge of seismogenic processes, and estimating both time-independent and time-dependent occurrence rates of strong earthquakes. We propose the application of physics-based earthquake simulators, requiring the knowledge of a robust geological-geophysical seismogenic model.

Description: Published

Description: JCR Journal