Institute Of Geophysics And Volcanology Research Articles

MUDA: dynamic geophysical and geochemical MUltiparametric DAtabase

Abstract. In this paper, the new dynamic geophysical and geochemical MUltiparametric DAtabase (MUDA) is presented. MUDA is a new infrastructure of the National Institute of Geophysics and Volcanology (INGV), published online in December 2023, with the aim of archiving and disseminating multiparametric data collected by multidisciplinary monitoring networks. MUDA is a MySQL relational database with a web interface developed in PHP, aimed at investigating possible correlations between seismic phenomena and variations in endogenous and environmental parameters in quasi real time. At present, MUDA collects data from different types of sensors such as hydrogeochemical probes for physical–chemical parameters in waters, meteorological stations, detectors of air radon concentration, diffusive flux of carbon dioxide (CO2) and seismometers belonging both to the National Seismic Network of INGV and to temporary networks installed in the framework of multidisciplinary research projects. MUDA publishes data daily, updated to the previous day, and offers the chance to view and download multiparametric time series selected for different time periods. The resultant dataset provides broad perspectives in the framework of future high-frequency and continuous multiparametric monitoring as a starting point to identify possible seismic precursors for short-term earthquake forecasting. MUDA can be accessed at https://doi.org/10.13127/muda (Massa et al., 2023).

Giant landslide, hidden caldera structure, magnetic anomalies and tectonics in southern Tyrrhenian Sea (Italy)

Phlegraean Fields and Ischia Island are large, densely populated, active volcanic structures located in the Campanian Tyrrhenian margin between the onshore and offshore sectors. While the emerged landforms provide significant insights into a series of intense volcano-tectonic events of the last 60 ka, our understanding of the sub-marine portion of these volcanoes remains limited due to its inaccessibility to direct exploration. In the last decades, the use of magnetic methods has proven to be useful in volcanic context, given the presence of large magnetization contrasts, whereas the implementation of a high-resolution Digital Elevation Model (DEM) has allowed the integration of detailed morphological analyses into the geophysical studies. In this work, we present two new high-resolution airborne and shipborne magnetic surveys, carried out by the National Institute of Geophysics and Volcanology (INGV) in the marine sector of the Phlegraean Fields caldera (Pozzuoli Bay) and surrounding sea sectors. Moreover, the new datasets have been integrated with older marine surveys carried out by the National Research Council (CNR) to extend the resulting magnetic anomaly map embracing the whole Campanian offshore volcanic structures, excluding Ischia Island. As a result, we present here three new magnetic anomaly maps used for an integrated interpretation of magnetic, morphological, and tectonic features. The study results provide valuable insights into the relationship between volcanic, magmatic, and tectonic activity, which may be useful for further investigations. Among the most notable findings are: the identification of the magnetic signatures of regional faults, previously unknown caldera structures, and a massive rock avalanche. Consequently, our research provides a significant contribution to seabed exploration aimed at identifying potential hazard factors in the study area.

Preliminary results in the automated detection of operational modal properties of the Portico Varano in the Camerino Ducal Palace

Portico Varano in the Ducal Palace of Camerino (Italy) is a renaissance monumental quadriporticus that was damaged by the 2016 Central Italy seismic sequence. Within the field activities for saving cultural heritage foreseen within a recent European research project named ARCH, a long-term monitoring system, comprising different types of sensors, such as accelerometers, displacement transducers, environmental sensors, and a weather station, was set up to achieve comprehensive measures of its operational behaviour and the evolution of the damage. The monitoring system, installed in October 2020, is currently operating, providing valuable information on the experimentally observed dynamic behaviour, also considering changes in the environmental conditions.Starting from the results of the dynamic characterization of the structure and after the optimization of the position of the sensors, this paper shows and discusses the efforts made to track over time the modal characteristics of the Portico Varano in order to detect changes in its conditions. In addition, a procedure has been proposed and implemented combining information available from Italian National Institute of Geophysics and Volcanology (INGV) to identify recorded data related to seismic events relevant to operational conditions.

Implementation of a seismic monitoring network of relevant and strategic public buildings in the Marche region (Italy)

A seismic monitoring infrastructure for relevant and strategic public buildings has been developed thanks to the agreement between the National Institute of Geophysics and Volcanology (INGV) and Marche Region. The project was founded by European projects for the assessment of seismic risk for strategic public buildings, prevention and monitoring - European Territorial Cooperation Project Holistic (EU IPA-Adriatic) and READINESS (INTERREG Italy-Croatia). The project was born by taking advantage of the presence of MEMS accelerometers installed at the base of municipal buildings. The project aims to implement low-cost technologies and non-invasive methods to extend the seismic monitoring of the sites where the structures are located and characterize the seismic action in correspondence of them with a rapid estimate of the damage through relationships between acceleration and macroseismic intensity or fragility curves and construction features. Among the various activities, environmental seismic noise measurements were carried to investigate the fundamental vibration of the structures and soils, semi-automatic procedures were developed for the calculation of the strong motion parameters of seismic events and a web portal was implemented for the collection and rapid dissemination of information to local Civil Protection.An important part of the activities concerned the testing of new MEMS accelerometers through collaboration with the Polytechnic University of Marche (UNIVPM) and the headquarter of the Osservatorio Nazionale Terremoti (ONT) in Palermo. Moreover, new monitoring sites are being prepared in some municipalities affected by the 2016 seismic sequence. Since the beginning of the project, the strong motion parameters relating to 95 seismic events of magnitude greater than 3 and with ground motion accelerations greater than or equal to 0.001 g have been stored in the database.

A Retrospective Analysis about the Italy Emilia M6.0 Earthquake Prediction

Cloud anomaly is a new kind of earthquake precursor that is still in the great controversy. Here we report an example of earthquake prediction based on cloud satellite anomaly. According to the cloud anomaly that appeared over eastern Italy on 21-23 April 2012, we made a prediction to Italy National Institute of Geophysics and Volcanology (INGV) that there will be a M5.5 - M6.0 earthquake in Italy in 30 days. Finally, the M6.0 quake occurred in northern Italy on 20 May 2012 and this verified our prediction. In this paper we extend the cloud image data from 2010 to 2013 and found 23 cloud anomalies totally, among them only the duration of the cloud on April 21-23 2012 exceed the 2 times, even 3 times of standard deviation threshold and it can be considered as a significant anomaly. Our analysis shows that the quake’s date and magnitude can be estimated accurately with the formula, and the epicenter can be estimated with the temperature anomaly method with 100 - 200 km error. This paper shows a promising method in earthquake prediction, of course it is only one example, and it still needs more examples to verify this method.

Graphic design and scientific research – the National Institute of Geophysics and Volcanology (INGV) experience

Abstract. One of the primary activities of the Istituto Nazionale di Geofisica e Vulcanologia (National Institute of Geophysics and Volcanology; INGV) is the production of resources concerning educational and outreach projects in geophysics and natural hazard topics. This activity is aimed at transferring, periodically, results at the forefront of ongoing research to the public through an intense and comprehensive plan for scientific dissemination. Over the past 15 years, graphic and visual communication have become essential tools for supporting institutional and research activities. In this paper, we describe successful INGV team experiences resulting from a close relationship and collaborative work between graphic designers and research scientists. The main goal of the projects devoted to the general public, through the creation of a museum exhibition or the production of descriptive brochures, is to support scientists in conveying their message and making concepts fruitful, easier to understand but also fully enjoyable thanks to the emotional involvement that images may generate. Through a careful composition of signs and images, and through the use of different visual tools (colours, form and lettering) on different media (print, video and web), the graphics and editorial products together create a strong INGV-style identity, making it easily recognizable in any educational and outreach project. A full project product package might include a logo or other artwork, organized text and pure design elements such as shapes and colours, which serve the purpose of unifying the whole set. Colour is used not only to help the project logo to stand out from the international overview but, in our case, also to generate a unifying return across all INGV sections. A recent and highly stimulating experience concerned the creation of edu-games, specifically designed for scientific dissemination, through a close collaboration between INGV graphic designers and their reference scientific community. The edu-games were designed as an effective combination of educational content and playful communicative aspects, leading the young players to learn while having fun.

Empirical fragility curves for Italian residential RC buildings

In this paper, empirical fragility curves for reinforced concrete buildings are derived, based on post-earthquake damage data collected in the aftermath of earthquakes occurred in Italy in the period 1976–2012. These data, made available through an online platform called Da.D.O., provide information on building position, building characteristics and damage detected on different structural components. A critical review of this huge amount of data is carried out to guarantee the consistency among all the considered databases. Then, an in-depth analysis of the degree of completeness of the survey campaign is made, aiming at the identification of the Municipalities subjected to a partial survey campaign, which are discarded from fragility analysis. At the end of this stage, only the Irpinia 1980 and L’Aquila 2009 databases are considered for further elaborations, as fully complying with these criteria. The resulting database is then integrated with non-inspected buildings sited in less affected areas (assumed undamaged), to account for the negative evidence of damage. The PGA evaluated from the shakemaps of the Italian National Institute of Geophysics and Volcanology (INGV) and a metric based on six damage levels according to EMS-98 are used for fragility analysis. The damage levels are obtained from observed damage collected during post-earthquake inspections through existing conversion rules, considering damage to vertical structures and infills/partitions. The maximum damage level observed on vertical structures and infills/partitions is then associated to the whole building. Fragility curves for two vulnerability classes, C2 and D, further subdivided into three classes of building height, are obtained from those derived for specific structural typologies (identified based on building height and type of design), using their frequency of occurrence at national level as weights.

A Global Archive of Coseismic DInSAR Products Obtained Through Unsupervised Sentinel-1 Data Processing

We present an automatic and unsupervised tool for the systematic generation of Sentinel-1 (S1) differential synthetic aperture radar interferometry (DInSAR) coseismic products. In particular, the tool first retrieves the location, depth, and magnitude of every seismic event from interoperable online earthquake catalogs (e.g., the United States Geological Survey (USGS) and the Italian National Institute of Geophysics and Volcanology (INGV) and then, for significant (with respect to a set of selected thresholds) earthquakes, it automatically triggers the downloading of S1 data and their interferometric processing over the area affected by the earthquake. The automatic system we developed has also been implemented within a Cloud-Computing (CC) environment, specifically the Amazon Web Services, with the aim of creating a global database of DInSAR S1 coseismic products, which consist of displacement maps and the associated wrapped interferograms and spatial coherences. This information will progressively be made freely available through the European Plate Observing System (EPOS) Research Infrastructure, thus providing the scientific community with a large catalog of DInSAR data that can be helpful for investigating the dynamics of surface deformation in the seismic zones around the Earth. The developed tool can also support national and local authorities during seismic crises by quickly providing information on the surface deformation induced by earthquakes.

Two-dimensional site seismic response analysis for a strategic building in Catania

This study is part of a more extensive research aimed to the seismic risk mitigation in Eastern Sicily. The earthquakes that occurred in Sicily in 1169, 1542, 1693, 1818, 1908 and more recently in 1990, testify the high level of seismic hazard in this region. It is well recognized that local seismic effects can exert a significant influence on the distribution of damage during earthquake. Traditionally, these effects are studied by means of simple one–dimensional (1-D) models of seismic wave propagation, which take only the influence of the stratigraphic profile and soil proprieties into to account for the site seismic response. It is known that the seismic response is strongly influenced by stratigraphic and topographic features that can reduce or amplify the earthquake induced ground motion depending on the soil stiffness and on the ground topography. This paper concerns the results of a two-dimensional (2-D) finite element analysis carried out to evaluate the response of the site where the National Institute of Geophysics and Volcanology (INGV) building is located in the town of Catania. The analysis, performed using as seismic input the accelerogram recorded in 1990 during the Santa Lucia earthquake, allowed to make some considerations about the expected accelerations at that the site and some comparison with the peak accelerations prescribed by Italian seismic code.

Dynamic behaviour of coupled soil-structure systems by means of FEM analysis for the seismic risk mitigation of INGV building in Catania (Italy)

Seismic design of new structures, as well as retrofitting and/or improving of existing ones should be definitely considered a multidisciplinary subject, which depends on many factors, such as: local site effects and the dynamic interaction between the foundation soil and the structure. The accurate investigation on the structure and the surrounding soil is the first fundamental step for a realistic evaluation of the structure seismic performance. The present paper deals with the Dynamic Soil Structure Interaction (DSSI) analysis concerning the INGV (National Institute of Geophysics and Volcanology) building in Catania, by means of a FEM 2D modeling. The building is a prestigious masonry structure situated in an area characterized by a high seismic hazard. Several accelerograms scaled at the same PHA, with reference to the estimated seismicity of Catania, have been adopted. Soil properties were carefully investigated by means of static and dynamic in-situ and laboratory tests. Many investigations were also performed on the structure. Equivalent linear visco-elastic constitutive models have been adopted both for the soil and the structure. For considering soil nonlinearity, degraded shear modula ( G ) and increased soil damping ratios ( D ) have been evaluated for all the involved soil layers, according to two different approach es. Firstly, soil nonlinearity has been modeled basing on the EC8 [2003] suggestions; secondly, it has been modeled choosing the values of G and D according to the effective strain levels obtained for each soil layer and for each different input, by means of an iterative sub-routine . The dynamic response of the system has been analyzed in the time and frequency domains. Results are presented in terms of: acceleration amplification factors, Fourier and response spectra, amplification functions and shear forces per floor. The main goals of the paper are: i) to investigate the acceleration profiles along the soil and the structure considering and not considering the DSSI; ii) to investigate the soil filtering effect in terms of predominant frequency considering and not considering the DSSI; iii) to compare the obtained results with the ones given by a simpler 1D free-field soil analysis; iv) to compare the soil amplification factors and the response spectra obtained by 1D and 2D models with that by the Italian technical code [NTC, 2008]; v) to highlight the influence of DSSI in the seismic response of the structure; vi) to evaluate the influence of different modeling of soil nonlinearity on the dynamic response of the soil and structure.

Opto-mechanical lab-on-fibre seismic sensors detected the Norcia earthquake

We have designed and developed lab-on-fibre seismic sensors containing a micro-opto-mechanical cavity on the fibre tip. The mechanical cavity is designed as a double cantilever suspended on the fibre end facet and connected to a proof mass to tune its response. Ground acceleration leads to displacement of the cavity length, which in turn can be remotely detected using an interferometric interrogation technique. After the sensors characterization, an experimental validation was conducted at the Italian National Institute of Geophysics and Volcanology (INGV), which is responsible for seismic surveillance over the Italian country. The fabricated sensors have been continuously used for long periods to demonstrate their effectiveness as seismic accelerometer sensors. During the tests, fibre optic seismic accelerometers clearly detected the seismic sequence that culminated in the severe Mw6.5 Norcia earthquake that struck central Italy on October 30, 2016. The seismic data provided by the optical sensors were analysed by specialists at the INGV. The wave traces were compared with state-of-the-art traditional sensors typically incorporated into the INGV seismic networks. The comparison verifies the high fidelity of the optical sensors in seismic wave detection, indicating their suitability for a novel class of seismic sensors to be employed in practical scenarios.

PROLOGUE

<p>In 1989 the first bases of what is now a strong and consolidated Spanish-Italian scientific relationship in Seismology and in Volcano-Seismology were established. The first stage took place at the University of Catania, in the former Department of Earth Sciences, placed in the old Science Faculty, when a pre-doctoral student from the University of Granada, Cartuja Observatory (now called Andalusian Institute of Geophysics), arrived to complete his formation in seismology. During this stage, in addition to the training process, new contacts with researchers and mainly with pre-doctoral students of the former International Institute of Volcanology of the Italian National Research Council (IIV-CNR) were stablished. These contacts have endured, grown and created a strong international scientific network with consolidated and credible research production. In a short time new working groups were integrated such as the Osservatorio Vesuviano in Naples or the Department of Physics of the University of Salerno from the Italian side, and the Department of Applied Physics of the University of Almería or the Volcanology Department of the Spanish Research Council (CSIC) in Spain. At the present this non-official (but very active) network comprises many Italian Research Centers belonging to the National Institute of Geophysics and Volcanology (INGV) such as Catania, Naples, Rome, Palermo, Pisa or Bologna; Italian Universities as Salerno, Naples, L’Aquila or Calabrian, several Spanish Universities such as Granada, Almería, Jaen, Complutense, Cádiz or La Laguna, but also from other countries such as USA, Russia, Ireland, Portugal, México, Argentina, Germany, France, Norway or UK among others. This collaboration includes a continuous pre-doctoral students training protocols in which the exchange of fellows among the different institutions is fluent. [...]</p>

Structural Strengthening of the Portico of the Santa Maria Dei Servi Church in Bologna

The porticoes, together with medieval masonry towers, are the architectural element which mainly characterizes the city of Bologna, northern Italy. These porticoes, which extend all inside the city centre for a total length of almost 40 kilometres, have a high artistic and cultural relevance at the point that they are candidates as “Unesco World Heritage Site”. One of portico of highest heritage value is that next to the church of Santa Maria dei Servi, which is suffering important structural pathologies requiring urgent strengthening interventions. The ones strictly necessary to preserve the stability have been already implemented. It is known that for historical constructions appropriate strategies of interventions are to be adopted with special attention in the aspects related to the compatibility, durability, integrity of the original configuration. The aim of this paper is to identify the main criticalities and priorities of interventions. Based on the identified criticalities and priorities possible strategies of interventions are finally identified. A possible cause of the actual bad state of conservation could be related to the continues vibrations induced by the traffic. For this reason, measurements noises have been recently conducted by the Italian National Institute of Geophysics and Volcanology (INGV) in order to quantify their influence of the stress levels of the columns of the portico.

An Italian proposal on the monitoring of underwater noise: Relationship between the EU Marine Strategy Framework Directive (MSFD) and marine spatial planning directive (MSP)

In recent years, many studies have evaluated the effects of anthropogenic acoustic disturbance on marine organisms. Sounds associated with shipping, seismic surveys, sonar, and many other such sources induce several types of effect on fish and marine mammals. In this regard, the European Marine Strategy Framework Directive 2008/56/EC has not only defined underwater acoustic noise as “the intentional or accidental introduction of acoustic energy in the water column from impulsive and diffuse sources”, but has also expressly identified it as a form of pollution.In 2014, the first Italian proposal has been defined with the aim of developing a widespread monitoring plan for sub-regions in European Union waters with respect to two different sub-programs concerning impulsive (Descriptor 11.1) and continuous low frequency (Descriptor 11.2) sounds. The objective of Marine Strategy Framework Directive is the implementation of a recording system for temporal-spatial data regarding impulsive sound sources arising from anthropogenic activities. The pressure, for Descriptor 11.1, is measured by evaluating the source level, or a suitable proxy for anthropogenic sound sources, measured over the frequency band 10 Hz–10 kHz (and up to 40 kHz for cetacean detection), that could have an impact on marine organisms.The Descriptor 11.2 would monitor trends in the ambient noise level within the 1/3 octave bands 63 and 125 Hz (centre frequency) (re 1 μΡa RMS; average noise level in these octave bands over a year) via observation stations. This monitoring plan aims to obtain noise maps of sea regions for the frequency band 10 Hz–10 kHz (and up to 40 kHz for cetacean detection) by improving existing geophysical/acoustic observation stations, e.g. those of the National Institute of Geophysics and Volcanology (INGV) and the National Institute of Nuclear Physics (INFN), as well as other medium- and long-term monitoring stations. The program also wants to define the level of damage caused by underwater noise, using underwater noise as an example to evaluate the impact of this type of noise on different marine organisms.Maritime spatial planning (MSP) and integrated coastal management (ICZM) have to employ an ecosystem-based approach that ensures the protection of the natural resources and provides the basis for carrying out the various monitoring activities. The Italian monitoring proposal on Descriptor 11 of Marine Strategy Framework Directive (MSFD) was used in order to analyze the strategic vision of the integrated maritime policy (IMP) between MSFD and MSP programs in terms of achieving Good Environmental Status (GES).

L'Aquila's Aftershocks Shake Scientists

I have been sentenced to 6 years of imprisonment for failing to give adequate advance warning to the population of L'Aquila, a city in the Abruzzo region of Italy, about the risk of the 6 April 2009 earthquake that led to 309 deaths. I have been found guilty despite illogical charges and accusations that set dangerous precedents for the future of the scientific process. The judge's ruling claims that citizens of L'Aquila would normally rush outside upon feeling an earth tremor, but that they did not in 2009 because a Major Risks Commission (CGR) meeting in L'Aquila, one week beforehand, had given them a false sense of security. However, this meeting was run, not by the National Institute of Geophysics and Volcanology (INGV), but by an arm of the Prime Minister's office: the Civil Protection Agency (CPA). An agreement between the INGV and the CPA states that the latter is exclusively responsible for communicating any state of risk. The INGV has always scrupulously adhered to that regulation. As a former president of the INGV, I never spoke to the media about the seismic situation at L'Aquila, and no relative of the victims suggested otherwise. Rather, the “proof” used by the public prosecutor was the CGR meeting minutes. At that meeting, I (and others) stated that Abruzzo, and particularly L'Aquila, is one of the worst earthquake zones in Italy. I then explained that earthquakes are not predictable for good scientific reasons and discussed some of the seismic mechanics involved. The Mayor of L'Aquila, Massimo Cialente, testified that he was struck by my statement about the local seismic risk at this meeting, and as a result he decided to close certain schools and recommend a state of emergency be declared. ![Figure][1] Seismic Hazard Map distributed by the National Institute of Geophysics and Volcanology. CREDIT: INGV At the CGR meeting, we also distributed the Seismic Hazard Map, made official in 2003 ([ 1 ][2]), which was largely the work of the INGV under my presidency. The map clearly shows Abruzzo as a hazardous zone. One of its goals was to inform administrators of what action to take to reduce seismic risk in the areas they governed. The maps were later made available to the public prosecutor, who ignored them just as he ignored the testimony of Mayor Cialente. As further evidence of my guilt, the public prosecutor completely distorted the argument of one of my journal publications ([ 2 ][3]), effectively putting science itself on trial. In that 1995 work, my colleagues and I highlighted the statistical importance of temporal “clustering”: various strong earthquakes in a (geologically) brief time span. We posited that the high probability rate calculated for the Aquilan territory is not statistically meaningful because it is based on three events that occurred between the 17th and 18th centuries—hardly a sufficient basis to describe what would happen in subsequent centuries. The public prosecutor's superficial interpretation of scientific results to bolster his argument sets a grave precedent for not only seismology but many other disciplines as well. Science is constantly evolving; research proceeds by trial and—as knowledge grows—error. When I wrote the “indicted” work, I was addressing my worldwide peers and awaiting their verification, as must be the way of all modern scientific research. In publishing an official map, seismologists have done all they currently can to protect society from earthquakes. I can hardly be blamed for the poor quality of buildings or for people's failure to conform to anti-seismic laws—these are the responsibilities of other authorities. The local CPA is responsible for accurate communication of risk and effective management of emergency situations. I did not disseminate false or imprudent information. My question is: What could I do to avoid conviction? I suppose I should have foreseen the earthquake! 1. [↵][4]1. M. Stucchi 2. et al ., Bull. Seismol. Soc. Am. 101, 1885 (2011). [OpenUrl][5][Abstract/FREE Full Text][6] 2. [↵][7]1. E. Boschi, 2. P. Gasperini, 3. F. Mulargia , Bull. Seismol. Soc. Am. 85, 1475 (1995). [OpenUrl][8][Abstract/FREE Full Text][9] 3. I want to express my strong friendship to Giulio Selvaggi, who was also wrongly accused in the L'Aquila trial. [1]: pending:yes [2]: #ref-1 [3]: #ref-2 [4]: #xref-ref-1-1 View reference 1 in text [5]: {openurl}?query=rft.jtitle%253DBulletin%2Bof%2Bthe%2BSeismological%2BSociety%2Bof%2BAmerica%26rft.stitle%253DBulletin%2Bof%2Bthe%2BSeismological%2BSociety%2Bof%2BAmerica%26rft.aulast%253DStucchi%26rft.auinit1%253DM.%26rft.volume%253D101%26rft.issue%253D4%26rft.spage%253D1885%26rft.epage%253D1911%26rft.atitle%253DSeismic%2BHazard%2BAssessment%2B%25282003-2009%2529%2Bfor%2Bthe%2BItalian%2BBuilding%2BCode%26rft_id%253Dinfo%253Adoi%252F10.1785%252F0120100130%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [6]: /lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6Nzoic3NhYnVsbCI7czo1OiJyZXNpZCI7czoxMDoiMTAxLzQvMTg4NSI7czo0OiJhdG9tIjtzOjIzOiIvc2NpLzM0MS82MTUzLzE0NTEuYXRvbSI7fXM6ODoiZnJhZ21lbnQiO3M6MDoiIjt9 [7]: #xref-ref-2-1 View reference 2 in text [8]: {openurl}?query=rft.jtitle%253DBulletin%2Bof%2Bthe%2BSeismological%2BSociety%2Bof%2BAmerica%26rft.stitle%253DBulletin%2Bof%2Bthe%2BSeismological%2BSociety%2Bof%2BAmerica%26rft.aulast%253DBoschi%26rft.auinit1%253DE.%26rft.volume%253D85%26rft.issue%253D5%26rft.spage%253D1475%26rft.epage%253D1482%26rft.atitle%253DForecasting%2Bwhere%2Blarger%2Bcrustal%2Bearthquakes%2Bare%2Blikely%2Bto%2Boccur%2Bin%2BItaly%2Bin%2Bthe%2Bnear%2Bfuture%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [9]: /lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6Nzoic3NhYnVsbCI7czo1OiJyZXNpZCI7czo5OiI4NS81LzE0NzUiO3M6NDoiYXRvbSI7czoyMzoiL3NjaS8zNDEvNjE1My8xNDUxLmF0b20iO31zOjg6ImZyYWdtZW50IjtzOjA6IiI7fQ==

The 2009 L'Aquila <italic>M</italic><sub>W</sub> 6.3 earthquake: a new technique to locate the hypocentre in the joint inversion of earthquake rupture process

SUMMARY A new technique is presented to jointly invert the teleseismic and Interferometric Synthetic Aperture Radar (InSAR) data by simultaneously searching for the hypocentre and the relative weight of InSAR data. In this technique, the parameters of causative fault is determined by using InSAR data first, and then the hypocentre is searched for by jointly inverting teleseismic and InSAR data with the assumption that each subfault on the fault is a potential hypocentre. With this technique, we investigated the source rupture process of the 2009 April 6 L’Aquila MW 6.3 earthquake without the use of the existing hypocentre locations. Our estimated hypocentre is 42.366°N, 13.385°E, depth 6.9 km, with an uncertainty of 1∼2 km, similar to the hypocentre (42.348°N, 13.380°E, depth 9.5 km) determined by National Institute of Geophysics and Volcanology (INGV) using arrival time data within the epicentral distance of 50 km. Our joint inversion suggests a scalar moment of 3.5 × 1018 Nm, equivalent to a moment magnitude of MW 6.3. The source process consists of two subevents with a total duration of 7.7 s. The first event (0∼3 s) corresponds to the slip patch near the hypocentre and the second (in the next 4.7 s) ruptured the other slip patch at 4∼16 km along the strike direction. These unilateral rupture characteristics of the L’Aquila earthquake are confirmed by the apparent source time functions (ASTFs) analysis. In addition, two resolution tests are performed to check the reliability of this work, clarifying the differences between the inversion results with teleseismic data only, InSAR data only and joint inversion, indicating that a higher resolution can be achieved through the joint inversion.

Analysis of Italian seismicity by using a nonextensive approach

Using the INGV (National Institute of Geophysics and Volcanology) seismic catalogue, nonextensive analysis of the instrumental seismicity of Italy was performed. The time span of the analyzed catalogue is from April 16, 2005 to March 31, 2009, and only events with magnitude M L ≥ 1.9 were considered. The analysis of the spatial variation of the nonextensive parameters q and a was performed by means of scanning the Italian territory by a 1° × 1° spatial window, with a shift of 0.2° in longitude and latitude. The nonextensive parameters were estimated by means of the Levenberg–Marquadt nonlinear least square fitting method, and the obtained results were checked for stability with the variation of a 0 and q 0 , the initial values of the parameters in the fitting procedure. It was found that the q value is relatively low in areas, in which the strongest events (M w > 5.5 during the last 40 years) occurred. This finding could suggest that different earthquake triggering mechanisms govern the Italian seismicity, stick–slip-like where q is relatively low and fragment-asperity interaction-type where q is relatively high. Of course new analyses from different areas are needed in order to test such findings.

Civil protection preparedness and response to the 2007 eruptive crisis of Stromboli volcano, Italy

Stromboli, one of the very few tourist volcanic islands in the world in permanent state of activity, has been the site of two important volcanic crises coupled with slope failure episodes in 2002–2003 and 2007. Due to the lucky circumstance that both crises have occurred in winter, the actual consequences on people were moderate. Nevertheless, the first crisis caused a few injuries, threatened the local population and caused relevant economic losses. The emotional impact on public opinion of the 30th December 2002 tsunami acted, in particular, as a trigger for civil protection initiatives aimed at structurally improving the standard volcano safety and preparedness measures to effectively deal with future crises. The main initiatives carried out during the 2003 crisis consisted in the setting up of: 1) new geophysical and geochemical volcano surveillance networks and 2) a local, permanent scientific/civil protection structure (COA, Centro Operativo Avanzato), where signals from volcano monitoring are visualized in real time and eventually used by the personnel of the Department of Civil Protection (DPC) for immediate activation of response procedures. This was followed by the setting up, in 2005, at the (DPC) in Rome, of a centre named “Centro Funzionale Centrale Rischio Vulcanico” (CFCRV), where the most relevant monitoring signals of Italian active volcanoes are visualized in real time and where activities of simple elaboration, for hazard assessment purpose are daily carried out and data sharing within the scientific community is coordinated by civil protection personnel with training in volcanic problems. The response effectiveness of the new system was tested on February–March 2007 when a new volcanic crisis occurred. An internal DPC “state of attention” was declared by the CF 15 days before the eruption onset when seismic and deformation parameters showed an abrupt increase up to values much higher than background. On February 27th the sudden onset of explosive activity outside the main craters and the occurrence of a small landslide down slope of the active craters were detected in real time on the screens of the CFCRV and by monitoring centres of the National Institute of Geophysics and Volcanology (INGV) and University of Florence (UNIFI). This enabled the DPC to immediately activate emergency crisis procedures and start a coordinated management of the crisis between civil protection personnel in Rome and COA. As accelerating slope movements were detected by ground deformation monitoring of UNIFI, a tsunami warning was launched shortly afterward. Warnings were also declared on 8th March and 15th March when slope movements resumed and a large explosion at the central craters occurred, respectively. From the end of February to May 2007 a scientific committee named “Scientific Synthesis Group” (SSG), appointed by the DPC, made daily evaluations of impending hazards in cooperation with CFCRV. During the crisis the DPC coordinated information activities with the media and island residents. The successful managing of the crisis consisted in minimizing risk for people and meanwhile facilitating normal activities and regular access to island.

Investigating the spatial variability of the time-scaling properties in Italian seismicity

Abstract. Significant power-law long-range correlated structures have been identified in the Italian seismicity from 1983 to 2003. We performed the Allan Factor Analysis and the Detrended Fluctuation Analysis on both the full and the aftershock-depleted seismic data, extracted by the INGV (National Institute of Geophysics and Volcanology) instrumental catalog.Our findings suggest that (i) the time-scaling behaviour characterizes mainly the Apennine chain; (ii) the time-correlated behaviour of the seismicity is persistent, and this implies that the dynamics underlying the seismic phenomenology is characterized by the presence of "positive feedback mechanisms"; (iii) significant time correlation is not simply related with the mainshock/aftershock mechanisms.