Papers by F. Giudicepietro

Il sito web dell'Osservatorio Vesuviano (INGV), istituito nella seconda metà del 1997, ha acquisi... more Il sito web dell'Osservatorio Vesuviano (INGV), istituito nella seconda metà del 1997, ha acquisito nel maggio del 2002 la sua attuale fisionomia, a seguito di una sostanziale ristrutturazione. Allo scopo di verificare il gradimento e l'impatto che il sito ha presso il pubblico è stato installato un software di statistiche web e di monitoraggio degli accessi. La scelta del software è stata improntata a criteri di semplicità d'uso e di economicità. Dopo una ricerca tra i prodotti più diffusi è stato scelto il pacchetto Awstats versione 6.4 (http://awstats.sourceforge.net/) che consente di ottenere tutte le informazioni di interesse e risulta di facile implementazione. AWStats è un' applicazione open source, distribuita sotto la GNU General Public License, che analizza i file di log prodotti da un web server presentando i dati in forma grafica di facile lettura. L'applicazione è sviluppata in perl e php e funziona con vari web server, quali Apache o IIS. Parametri monitorati I principali parametri monitorati dal sistema di controllo degli accessi al sito Web dell'Osservatorio Vesuviano sono: o Visitatore singolo (Host). È l'indirizzo IP o hostname che ha effettuato richieste al server in un tempo di riferimento, es. un mese. Se lo stesso IP si collega più volte nel periodo di riferimento è conteggiato una sola volta come singolo visitatore. In certi casi più utenti possono figurare come un singolo host, quando ad esempio esso corrisponde a quello della rete locale di una grande azienda e la connessione di ogni workstation appare provenire sempre dallo stesso host, ma ci sono anche molti altri casi specifici.

Frontiers in Earth Science
Open conduit volcanoes like Stromboli can display elusive changes in activity before major erupti... more Open conduit volcanoes like Stromboli can display elusive changes in activity before major eruptive events. Starting on December 2020, Stromboli volcano displayed an increasing eruptive activity, that on 19 May 2021 led to a crater-rim collapse, with pyroclastic density currents (PDCs) that spread along the barren NW flank, entered the sea and ran across it for more than 1 km. This episode was followed by lava flow output from the crater rim lasting a few hours, followed by another phase of lava flow in June 2021. These episodes are potentially very dangerous on island volcanoes since a landslide of hot material that turns into a pyroclastic density current and spreads on the sea surface can threaten mariners and coastal communities, as happened at Stromboli on 3 July and 28 August 2019. In addition, on entering the sea, if their volume is large enough, landslides may trigger tsunamis, as occurred at Stromboli on 30 December 2002. In this paper, we present an integration of multidis...

arXiv (Cornell University), Feb 24, 2022
The MURAVES experiment aims at the muographic imaging of the internal structure of the summit of ... more The MURAVES experiment aims at the muographic imaging of the internal structure of the summit of Mt. Vesuvius, exploiting muons produced by cosmic rays. Though presently quiescent, the volcano carries a dramatic hazard in its highly populated surroundings. The challenging measurement of the rock density distribution in its summit by muography, in conjunction with data from other geophysical techniques, can help the modeling of possible eruptive dynamics. The MURAVES apparatus consists of an array of three independent and identical muon trackers, with a total sensitive area of 3 square meters. In each tracker, a sequence of 4 XY tracking planes made of plastic scintillators is complemented by a 60 cm thick lead wall inserted between the two downstream planes to improve rejection of background from low energy muons. The apparatus is currently acquiring data. Preliminary results from the analysis of a first data sample are presented.

Geophysical Research Letters
We investigate the 19 September 2021 eruption of the Cumbre Vieja volcano (La Palma, Canary Islan... more We investigate the 19 September 2021 eruption of the Cumbre Vieja volcano (La Palma, Canary Islands, Spain). In particular, we analyze the Differential Interferometric Synthetic Aperture Radar (DInSAR) measurements obtained by processing Sentinel‐1 images acquired from both ascending and descending orbits. First, we show the importance, for oceanic islands like La Palma, of investigating DInSAR products retrieved from time series, instead of single interferograms, to effectively remove possible atmospheric artifacts within the displacement measurements. Subsequently, we invert the retrieved data through analytical modeling. Our results highlight that a sill–like source was active in the pre–eruptive phase (8–16 September), whereas the action of two dikes prevailed during the co‐eruptive phase (17–22 September). This evolution suggests a process of magma rising through a network of interconnected sills and dikes. The seismicity, that preceded and accompanied the onset of the eruption...

We present a new strategy for reliable automatic classification of local seismic signals and volc... more We present a new strategy for reliable automatic classification of local seismic signals and volcano-tectonic earthquakes (VT). The method is based on a supervised neural network in which a new approach for feature extraction from short period seismic signals is applied. To reduce the number of records required for the analysis we set up a specialized neural classifier, able to distinguish two classes of signals, for each of the selected stations. The neural network architecture is a multi-layer perceptron (MLP) with a single hidden layer. Spectral features of the signals and the parameterized attributes of their waveform have been used as input for this network. Feature extraction is done by using both the linear predictor coding tech-nique for computing the spectrograms, and a function of the amplitude for charac-terizing waveforms. Compared to strategies that use only spectral signatures, the inclusion of properly normalized amplitude features improves the performance of the clas...

Scientific Reports, 2021
The knowledge of the dynamic of the Campi Flegrei calderic system is a primary goal to mitigate t... more The knowledge of the dynamic of the Campi Flegrei calderic system is a primary goal to mitigate the volcanic risk in one of the most densely populated volcanic areas in the world. From 1950 to 1990 Campi Flegrei suffered three bradyseismic crises with a total uplift of 4.3 m. After 20 years of subsidence, the uplift started again in 2005 accompained by a low increment of the seismicity rate. In 2012 an increment in the seismic energy release and a variation in the gas composition of the fumaroles of Solfatara (in the central area of the caldera) were recorded. Since then, a slow and progressive increase in phenomena continued until today. We analyze the INGV - Osservatorio Vesuviano seismic catalogue of Campi Flegrei from 2000 to 2020 in order to look for any variation in the seismic parameters and compare them with geochemical monitored ones. A remarkable correlation between independent variables of earthquake cumulative number, CO/CO2 values and vertical ground deformation reveals...

Remote Sensing, 2021
Strombolian activity varies in magnitude and intensity and may evolve into a threat for the local... more Strombolian activity varies in magnitude and intensity and may evolve into a threat for the local populations living on volcanoes with persistent or semi-persistent activity. A key example comes from the activity of Stromboli volcano (Italy). The “ordinary” Strombolian activity, consisting in intermittent ejection of bombs and lapilli around the eruptive vents, is sometimes interrupted by high-energy explosive events (locally called major or paroxysmal explosions), which can affect very large areas. Recently, the 3 July 2019 explosive paroxysm at Stromboli volcano caused serious concerns in the local population and media, having killed one tourist while hiking on the volcano. Major explosions, albeit not endangering inhabited areas, often produce a fallout of bombs and lapilli in zones frequented by tourists. Despite this, the classification of Strombolian explosions on the basis of their intensity derives from measurements that are not always replicable (i.e., field surveys). Hence...

Journal of Volcanology and Geothermal Research, 2021
Fluids supplied by stored magma at depth are causal factors of volcanic unrest, as they can cause... more Fluids supplied by stored magma at depth are causal factors of volcanic unrest, as they can cause pressurization/ heating of hydrothermal systems. However, evidence for links between hydrothermal pressurization, CO 2 emission and volcano seismicity have remained elusive. Here, we use recent (2010−2020) observations at Campi Flegrei caldera (CFc) to show hydrothermal pressure, gas emission and seismicity at CFc share common source areas and well-matching temporal evolutions. We interpret the recent escalation in seismicity and surface gas emissions as caused by pressure-temperature increase at the top of a vertically elongated (0.3-2 km deep) gas front. Using mass (steam) balance considerations, we show hydrothermal pressurization is causing energy transfer from the fluids to the host rocks, ultimately triggering low magnitude earthquakes within a seismogenetic volume containing the hydrothermal system. This mechanism is probably common to other worldwide calderas in similar hydrothermal activity state.

Scientific Reports, 2020
This is a seven-year study (1/7/2011-31/12/2017) of radon monitoring at two sites of Campi Flegre... more This is a seven-year study (1/7/2011-31/12/2017) of radon monitoring at two sites of Campi Flegrei caldera (Neaples, Southern Italy) that in the last 70 years experienced repeated phases of volcanic unrest. The sites are equipped with devices for radon detection, based on the spectrometry analysis of the α-particles of radon daughters. A hybrid method, as combination of three known methods, is applied for the identification of residuals (anomalies) and trends of the time series of Radon. The results are compared with the following indicators of current caldera unrest: the tremor caused by the major fumarolic vent registered by a seismic station; the cumulative of background seismicity; the maximum vertical deformation acquired by GPS networks during the current phase of uplift; the temperature-pressure of the hydrothermal system estimated based on gas geo-indicators. The comparisons show strong correlation among independent signals and suggest that the extension of the area affected...

Applied Radiation and Isotopes, 2020
The present work concerns a detailed analysis of Radon time series to differentiate endogenous fr... more The present work concerns a detailed analysis of Radon time series to differentiate endogenous from exogenous phenomena which provide anomalous signals. Two-year data from two sites in Czech Republic and in Italy are analyzed in order to contribute to the prevention of natural hazards. A new hybrid forecasting method is implemented and tuned for the identification of Radon anomalies in the time series. It is based on the combination of Multiple Linear Regressions, Empirical Mode Decomposition and Support Vector Regression methods that decompose the signal and analyze the components to distinguish the variations due to Radon originated in depths from those due to environmental parameters. The possible correlations with fumarolic tremors in the Italian site and the faults microdisplacements in the Czech site have been studied, as well as with the earthquakes that have influence on two studied areas. Results show that: (i) the used method is very effective considering the calculated statistical uncertainties; (ii) the outer temperature is the main influencing Radon driving force; (iii) the extracted Radon anomalies due to endogenous phenomena are well correlated with fault displacements, fumarolic tremors, and with earthquakes under a characteristic delay time for each area; (iv) significant correlations among earthquake magnitude and depth with fault displacement and fumarolic tremor are found.

Journal of Instrumentation, 2020
A : Muon radiography is a technique based on the measurement of absorption profiles of muons as t... more A : Muon radiography is a technique based on the measurement of absorption profiles of muons as they pass through matter. This measurement allows to obtain an image of the inner structure of large volume objects and is suitable to be applied in several fields, such as volcanology, archaeology and civil engeneering. One of the main applications concerns the study of volcanic structures; indeed it is possible to use this technique to measure the mass distribution inside the edifice of a volcano providing useful information to better understand the possible eruption mechanisms. The MURAVES (MUon RAdiography of VESuvius) project aims to the study of the summital cone of Mt. Vesuvius near Naples in Italy, one of the most dangerous active volcanoes in the world. The MURAVES apparatus is a modular, robust muon hodoscope system with a low power consumption, optimized to be used in inhospitable environments like the surroundings of volcanoes. The complete detection system is an array of identical tracking modules, each with an area of 1 m 2 , based on the use of plasic scintillators. The technologies, the status and the data analysis strategy of the experiment will be presented in this paper.
EPJ Web of Conferences, 2018
The MURAVES (MUon RAdiography of VESuvius) project is a joint activity participated by INGV, INFN... more The MURAVES (MUon RAdiography of VESuvius) project is a joint activity participated by INGV, INFN and the Universities of Naples “Federico II” and Florence. The collaboration, following the experience gained within the previous INFN R&D project Mu-Ray, is currently completing the production of a robust four square meter low power consumption detector to be installed on the flank of Mount Vesuvius, an active volcano located on the western coast of Italy. The detector is supposed to collect data for at least one year, thus allowing performing a scan of the structure of the Vesuvius volcanic cone. In this work the status of the project and some parallel activities on muon radiography are presented.
Seismological Research Letters, 2018

Geophysical Research Letters, 2018
The causative source of the first damaging earthquake instrumentally recorded in the Island of Is... more The causative source of the first damaging earthquake instrumentally recorded in the Island of Ischia, occurred on 21 August 2017, has been studied through a multiparametric geophysical approach. In order to investigate the source geometry and kinematics we exploit seismological, Global Positioning System, and Sentinel‐1 and COSMO‐SkyMed differential interferometric synthetic aperture radar coseismic measurements. Our results indicate that the retrieved solutions from the geodetic data modeling and the seismological data are plausible; in particular, the best fit solution consists of an E‐W striking, south dipping normal fault, with its center located at a depth of 800 m. Moreover, the retrieved causative fault is consistent with the rheological stratification of the crust in this zone. This study allows us to improve the knowledge of the volcano‐tectonic processes occurring on the Island, which is crucial for a better assessment of the seismic risk in the area.

Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2018
Cosmic-ray muon radiography (muography), an imaging technique that can provide measurements of ro... more Cosmic-ray muon radiography (muography), an imaging technique that can provide measurements of rock densities within the top few 100 m of a volcanic cone, has now achieved a spatial resolution of the order of 10 m in optimal detection conditions. Muography provides images of the top region of a volcano edifice with a resolution that is considerably better than that typically achieved with other conventional methods (i.e. gravimetric). We expect such precise measurements, to provide us with information on anomalies in the rock density distribution, which can be affected by dense lava conduits, low-density magma supply paths or the compression with the depth of the overlying soil. The MUon RAdiography of VESuvius (MURAVES) project is now in its final phase of construction and deployment. Up to four muon hodoscopes, each with a surface of roughly 1 m 2 , will be installed on the slope of Vesuvius and take data for at least 12 months. We will use the muographic profiles, combined with d...
Journal of Instrumentation, 2014
ABSTRACT Muon Radiography allows to map the density of a volcanic cone. It is based on the measur... more ABSTRACT Muon Radiography allows to map the density of a volcanic cone. It is based on the measurement of the attenuation of the flux of muons present in the cosmic radiation on the ground. The MU-RAY project has developed an innovative detector designed for the muon radiography. The main features are the low electric power consumption, robustness and transportability, good spatial resolution and muon time of flight measurement. A 1 m(2) detector prototype has been constructed. and collected data at Mt. Vesuvius for approximately 1 month in spring 2013. A second campaign of measurement has been performed at the Puy de Dome, France, in the last four months of 2013. In this article the principles of muon radiography, the MU-RAY detector and the first results from the collected data will be described.

Automatic detection and classification methods are increasingly important in observatory operatio... more Automatic detection and classification methods are increasingly important in observatory operations, as the volume and rate of incoming data exceed the capacity of human analysis staff to process the data in near-real-time. We explore the success of scanning detection for similar event identification in a variety of seismic waveform catalogs. Several waveform pre-processing methods are applied to previously recorded events which are scanned through triggered and continuous waveform catalogs to determine the success and false alarm rate for detections of repeating signals. Pre-processing approaches include adaptive, cross-coherency filtering, adaptive, auto-associative neural network filtering, discrete wavelet package decomposition and linear predictive coding as well as suites of standard bandpass filters. Classification / detection methods for the various pre-processed signals are applied to investigate the robustness of the individual and combined approaches. The classifiers as a...
Salvatore Alparone (1), Vincenzo Augusti (2), Alessandro Bonaccorso (1), Giuseppe Borriello (2), ... more Salvatore Alparone (1), Vincenzo Augusti (2), Alessandro Bonaccorso (1), Giuseppe Borriello (2), Ciro Buonocunto (2), Pasqualino Cappuccio (1), Antonio Caputo (2), Mario Castellano (2), Danilo Contrafatto (1), Luca D’Auria (3), Walter De Cesare (2), Bellina Di Lieto (2), Antonietta M. Esposito (2), Giuseppe Falzone (1), Angelo Ferro (1), Flora Giudicepietro (2), Graziano Larocca (1), Giuseppe Laudani (1), Marcello Martini (2), Massimo Orazi (2), and the INGV STROMBOLI TEAM
Applied Radiation and Isotopes, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
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Papers by F. Giudicepietro