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The Third Plasma Density Peak at Poleward of EIA Crest: Swarm and ICON Observations
No full textIn this study, we focus on the presence of the ionospheric third plasma density peak associated with the equatorial ionization anomaly (EIA) based on observations from the ESA's Swarm constellation. By statistically analyzing the third peaks observed by the Swarm A and B at two different altitudes, we found that such structure appears mainly around ±20°magnetic latitude (Mlat), namely the poleward of the EIA crests. In the meanwhile, the third peak shows prominent season and local time dependences, that are mainly observed in the summer hemisphere during solstice seasons and with the highest occurrence in the afternoon hours. However, no clear solar flux and magnetic activity dependences are found. By further analyzing the simultaneous neutral wind measurements from the ionospheric connection explorer satellites, we found that the summer-to-winter hemispheric meridional wind is responsible for causing the third peak as well as its seasonal dependence (higher occurrence in the summer hemisphere). In addition, the third-peak structure shows prominent longitudinal dependence. In regions where the magnetic declination directs eastward, it has a larger occurrence in the southern hemisphere, while in regions where the magnetic declination reverses, it has a larger occurrence in the northern hemisphere. Such a longitudinal dependence suggests that the zonal wind, which has a magnetic field-aligned component at favorable magnetic declination regions, contributes also to the formation of the third-peak structure.PublishedJCR Journa
Seismic attenuation and stress on the San Andreas Fault at Parkfield: are we critical yet?
No full textThe Parkfield transitional segment of the San Andreas Fault (SAF) is characterized by the production of frequent quasi-periodical M6 events that break the very same asperity. The last Parkfield mainshock occurred on 28 September 2004, 38 years after the 1966 earthquake, and after the segment showed a ∼22 years average recurrence time. The main reason for the much longer interevent period between the last two earthquakes is thought to be the reduction of the Coulomb stress from the M6.5 Coalinga earthquake of 2 May 1983, and the M6 Nuñez events of June 11th and 22 July 1983. Plausibly, the transitional segment of the SAF at Parkfield is now in the late part of its seismic cycle and current observations may all be relative to a state of stress close to criticality. However, the behavior of the attenuation parameter in the last few years seems substantially different from the one that characterized the years prior to the 2004 mainshock. A few questions arise: (i) Does a detectable preparation phase for the Parkfield mainshocks exist, and is it the same for all events? (ii) How dynamically/kinematically similar are the quasi-periodic occurrences of the Parkfield mainshocks? (iii) Are some dynamic/kinematic characteristics of the next mainshock predictable from the analysis of current data? (e.g., do we expect the epicenter of the next failure to be co-located to that of 2004?) (iv) Should we expect the duration of the current interseismic period to be close to the 22-year “undisturbed” average value? We respond to the questions listed above by analyzing the non-geometric attenuation of direct S-waves along the transitional segment of the SAF at Parkfield, in the close vicinity of the fault plane, between January 2001 and November 2023. Of particular interest is the preparatory behavior of the attenuation parameter as the 2004 mainshock approached, on both sides of the SAF. We also show that the non-volcanic tremor activity modulates the seismic attenuation in the area, and possibly the seismicity along the Parkfield fault segment, including the occurrence of the mainshocks.Published1349425OST3 Vicino alla fagliaJCR Journa
La geoetica per riscrivere il complesso sistema di relazioni dell’umano
No full textLa geoetica (Peppoloni et al. 2019; Peppoloni e Di Capua 2021a,b,c) è una disciplina all’intersezione tra geoscienze (o scienze della Terra), filosofia, economia e sociologia. La geoetica si è sviluppata inizialmente come ambito di riflessione e prassi intra-disciplinare delle geoscienze, focalizzandosi sul significato culturale, sul valore sociale e sulle implicazioni etiche della conoscenza e della pratica geoscientifica. La geoetica si è da subito interrogata sul ruolo che gli operatori delle geoscienze (i geoscienziati) svolgono nella società e quali sono i loro doveri etici quando producono conoscenza, quando comunicano il loro sapere alla popolazione e ai decisori politici, quando contribuiscono alla difesa dai rischi naturali e si adoperano per l’uso prudente delle risorse minerarie ed energetiche del pianeta. Le discussioni intra-disciplinari si sono quindi concentrate inizialmente sulle questioni deontologiche, su come svolgere al meglio le proprie attività di studio e ricerca nel rispetto del metodo scientifico, su come interagire con colleghi e committenti per assicurare alti standard scientifici e tecnologici, su come rendere la comunità scientifica e professionale più inclusiva e rispettosa verso i suoi membri (Peppoloni e Di Capua 2012, 2020a, 2021a; Lollino et al. 2014; Wyss and Peppoloni 2015; Gundersen 2017; Mogk e Bruckner 2020). Tuttavia, è apparso subito evidente che le riflessioni all’interno delle geoscienze fossero solo una prima forma di approccio a questioni non strettamente tecniche della ricerca e della professione geoscientifica. Le analisi e le riflessioni della geoetica hanno cominciato a guardare fuori dell’ambito intra-disciplinare per addentrarsi all’interno di problemi più complessi che riguardano l’intera società, la sua organizzazione e i suoi riferimenti etici (Bohle e Preiser 2019; Peppoloni et al. 2017, 2019; Peppoloni e Di Capua 2020a,b; 2021a,b,c,d; Peppoloni 2020; Bohle e Marone 2021; Di Capua et al. 2021).Published147-188OS: Terza mission
Decolonizing western science education and knowledge in early childhood: Rethinking natural hazards and disasters framework through indigenous ‘ecology of knowledges’ in Kenya
No full textThis article presents the epistemological complexity inherent in the roll out of an international project on Disaster and Risk Reduction, and consequently about science education in the Indigenous context of Turkana County in Kenya. After an introduction that explains the current state of Disaster and Risk Reduction, the paper focuses on the ‘Paper Volcanoes Laboratory’ program and toolkit for children and teachers, which aims to spread awareness about natural hazards among children. The paper argues that the geographical, social and educational context where the project is carried out is critical to consider, and decolonial studies provide a conceptual and theoretical framework for this project. This allows to recognize reproduction of infantilization of Indigenous people and children through Western knowledge and science if implemented without consideration for local contexts, and demonstrates how Western educational projects have been a tool of discrimination and colonization. However, at the same time, it opens up the possibility for a dialogue and an encounter between the different epistemologies present in a project that was conceptualized within the Western context, but is to be carried out in Turkana County in Kenya.IUGG grantPublished197-213OSV4: Preparazione alle crisi vulcanicheJCR Journa
IMD: A Dating Code to Facilitate the Study of Transient Phenomena on the Surface of Mars
No full textSee also the related software "INGV Martian Dating (IMD) applications": http://hdl.handle.net/2122/16819Today, we have satellite images of Mars with a resolution of up to 24 cm per pixel. The planet has a thin atmosphere compared to Earth’s, but its surface is revealing itself to be active and complex. The use of images is an increasingly precise means of investigation for the study of transient phenomena that occur on the surface of the planet. We have developed a dating code that could be useful in the study of such phenomena. Thanks to this dating code, it is possible to immediately understand what season is in progress in the observed area starting from the terrestrial reference date of the photos taken by the orbiters. Some intermediate parameters of this calculation, such as the Martian year and the day of the year, can be equally useful for similar investigations. Satellite study of transient phenomena observable on the surface of Mars can range from geology (wind erosion and sedimentation) to meteorology (wind and phase transitions) to indigenous or non-indigenous biology.Published108OSA3: Climatologia e meteorologia spazialeJCR Journa
Gravimetry and hydrologic data to constrain the hydrodynamics of a karstic area: The Škocjan Caves study case
No full textIn this paper we employ a combination of gravity and hydrologic data to constrain a hydraulic model of the Škocjan Caves, an allogenic dominated karstic system in Slovenia. The gravity time-series recorded by a spring-based gravimeter, are carefully analyzed to remove tidal and non-tidal effects and unveil the local hydrologic contribution, which is influenced by the temporary accumulation of water in the cave system during the flood events of the Reka river.
We make use of a combined analysis of three large flood events with peak river discharge of about 200, 230 and 300 m3/s, that caused significant water level and gravity variations sensed by the pressure transducer and by the gravimeter. By the integration of hydraulic modelling we study the different coupled gravimetric-hydrologic responses to these flood events: we show that, depending on the peak discharge and duration of the event, different flow conditions are present in the cave system. In addition to the information provided by the pressure transducer, the gravimeter is sensitive to the flow dynamics in a different sector of the cave due to the choice of its location; this configuration helps to better constrain the hydraulic model.
Moreover, we find that the autogenic recharge by percolating water can significantly affect the gravity time-series and must be considered in related models. By inclusion of both the hydraulic model outcomes and of the modelling of the autogenic recharge, we are able to better explain the gravity transients during the two smaller magnitude events. In particular, during such events the autogenic contribution produces a transient gravity signal, which is about 4 times larger than the allogenic one, while during the largest flood the allogenic contribution drastically overcomes the autogenic effect by a factor 20.
By discussing this case, we prove the potential of terrestrial gravity observation to depict the hydro-dynamics of these complex karstic systems as well as the potential of gravimetry to remotely monitor these storage units.Published130453JCR Journa
Lessons Learnt from Monitoring the Etna Volcano Using an IoT Sensor Network through a Period of Intense Eruptive Activity
No full textThis paper describes the successes and failures after 4 years of continuous operation of a network of sensors, communicating nodes, and gateways deployed on the Etna Volcano in Sicily since 2019, including a period of Etna intense volcanic activity that occurred in 2021 and resulted in over 60 paroxysms. It documents how the installation of gateways at medium altitude allowed for data collection from sensors up to the summit craters. Most of the sensors left on the volcanic edifice during winters and during this period of intense volcanic activity were destroyed, but the whole gateway infrastructure remained fully operational, allowing for a very fruitful new field campaign two years later, in August 2023. Our experience has shown that the best strategy for IoT deployment on very active and/or high-altitude volcanoes like Etna is to permanently install gateways in areas where they are protected both from meteorological and volcanic hazards, that is mainly at the foot of the volcanic edifice, and to deploy temporary sensors and communicating nodes in the more exposed areas during field trips or in the summer season.Published1577OSV3: Sviluppo di nuovi sistemi osservazionali e di analisi ad alta sensibilitàJCR Journa
What Is the Effect of Seismic Swarms on Short-Term Seismic Hazard and Gutenberg-Richter b-Value Temporal Variation? Examples from Central Italy, October–November 2023
No full textA seismic hazard can be quantified by using probabilities. Modern seismic forecasting models (e.g., Operational Earthquake Forecasting systems) allow us to quantify the short-term variations in such probabilities. Indeed these probabilities change with time and space, in particular after strong seismic events. However, the short-term seismic hazard could also change during seismic swarms, i.e., a sequence with several small-/medium-sized events. The goal of this work is to quantify these changes, using the Italian Operational Earthquake Forecasting system, and also estimate the variations in the Gutenberg–Richter b-value. We focus our attention on three seismic swarms that occurred in Central Italy in October–November 2023. Our results indicate that short-term variations in seismic hazard are limited, less than an order of magnitude, and also that b-value variations are not significant. Placing our findings in a more general context, we can state that according to currently available models and catalogs, the occurrence of seismic swarms does not significantly affect the short-term seismic hazard.Published49OST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impattoJCR Journa
A multidisciplinary approach for the diagnostics of the stone building materials of architectural structures
No full textThe integrated use of non-destructive geomatic and geophysical techniques such as close-range
digital photogrammetry, laser scanner techniques, thermography, sonic and ultrasonic methods,
resistivity, etc... for the diagnostics of the stone building materials of architectural structures has
become increasingly dependent on the integration of different disciplines of applied research. As
is well known many historic monuments are characterized by severe damage due to temporal
degradation, problems caused by differential settlements of the foundations and various types of
natural hazards. Therefore it is of great interest to test and develop effective, integrated non
invasive procedures to detect the conservation state of the building materials of historic
structures, and identify and prevent their potential vulnerability in order to preserve their intrinsic
characteristics for a long time.
For extensive applications, as well as for investigations on monuments or large architectural
elements, scanning and digital high resolution images are particularly useful, thanks to their
limited cost, high production and relatively simple reproducibility of the tests. These techniques
give useful information on the shallow conditions of the investigated materials. Geophysical
techniques such as the ultrasonic and resistivity methods are non-invasive and are considered the
most appropriate to evaluate the internal structure and assess the quality of the stone materials
of the architectural heritage.
This paper presents an integrated approach that combines advanced geomatic survey procedures,
such as close-range photogrammetry (CRP) based on high resolution images and Terrestrial Laser
Scanner (TLS) techniques with a few geophysical techniques such as the ultrasonic and resistivity
ones in order to test the effectiveness of the integrated approach in providing an effective
diagnosis of stone building materials in the Basilica di San Saturnino (Cagliari – Italy). This Basilica
is the oldest monument of the town of Cagliari (Italy) and represents an interesting synthesis of
different construction techniques with heterogeneous stone materials of different origins. CRP
and TLS were applied to the investigated elements with the aim of obtaining a natural colour
texturized 2D-3D model with a calibrated scale and coordinates. The geometrical anomaly and
reflectivity maps derived from the data of the CRP-TLS survey show the presence of some
anomalies worthy of attention, but they were referred to the shallow materials. A further
investigation on site using the ultrasonic pulse velocity (UPV) and electrical resistivity techniques
were performed to investigate the materials in depth. The results of the CRP and TLS techniques
allowed the best design of the ultrasonic and electrical techniques and also proved to be useful in
the data interpretation phase.PublishedVienna - AustriaOSA5: Energia e georisors
The temporary seismic network FXLand: contribution to the project Fiber Optic Cable Use For Seafloor Studies Of Earthquake - FOCUS
No full textNel 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.Published1-26OST1 Alla ricerca dei Motori GeodinamiciOST3 Vicino alla fagliaN/A or not JC