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04.05. Geomagnetism
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- PublicationOpen AccessA geomagnetic reference model for Albania, Southern Italy and the Ionian Sea from 1990 to 2005(2004)
; ; ; ; ; ; ;Duka, B.; Department of Physics, Faculty of Natural Sciences, University of Tirana, Albania ;Gaya-Piqué, L. R.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;De Santis, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Bushati, S.; Academy of Sciences of Albania, Tirana, Albania ;Chiappini, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Dominici, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; ; ; ; ; Taking advantage of the measurements undertaken during the Albanian and Italian magnetic repeat station networks since 1990, as well as of a selected set of Ørsted satellite total field measurements, a magnetic reference model for the region comprising the Albanian territory, the southern part of the Italian Peninsula, and the Ionian Sea is presented. The model, designed to model the components of the main geomagnetic field for epochs between 1990 and 2005, has been developed by means of spherical cap harmonic analysis applied to a cap of semiangle 8°, larger than that investigated to take into account the appropriate spatial wavelength content of the main geomagnetic field over the region. The goodness of the fit to the real data suggests that the model can be used as a reference model to reduce magnetic surveys developed in the area during the time of validity of the model.288 182 - PublicationOpen AccessGeomagnetic field observations at a new Antarctic site, within the AIMNet project(2010-05-02)
; ; ; ; ; ; ; ; ; ;Lepidi, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Cafarella, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Santarelli, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Pietrolungo, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Urbini, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Piancatelli, A.; Universita’ di L’Aquila, L’Aquila, Italy., (3) British Antarctic Survey, Cambridge, UK ;Biasini, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Di Persio, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Rose, M.; British Antarctic Survey, Cambridge, UK; ; ; ; ; ; ; ; During the 2007-2008 antarctic campaign, the Italian PNRA installed a Low Power Magnetometer within the framework of the AIMNet (Antarctic International Magnetometer Network) project, proposed and coordinated by BAS. The magnetometer is situated at Talos Dome, around 300 km geographically North-West from Mario Zucchelli Station (MZS), and approximately at the same geomagnetic latitude as MZS. In this work we present a preliminary analysis of the geomagnetic field 1-min data, and a comparison with simultaneous data from different Antarctic stations.261 366 - PublicationOpen AccessOn fast and slow Earth’s magnetospheric dynamics during geomagnetic storms: a stochastic Langevin approachAbstract – The Earth’s magnetosphere responds to the external changes of interplanetary magnetic field and solar wind conditions showing a multiscale dynamics, manifesting in the occurrence of fluctuations over a very wide range of timescales. Here, using an approach based on a Langevin/Fokker-Planck description we investigate the nature of the fast (short-) and slow (long-timescale) fluctuations of SYM-H index during geomagnetic storms. The results point towards a different origin of the fast (s < 200 min) and slow (s > 200 min) fluctuations, which are characterized by state functions of different nature. In detail, the state function associated with the slow dynamics shows the evidence of the occurrence of first-order-like topological phase transition during the different phases of a geomagnetic storm, while the fast dynamics seems to be characterized by a quasi-invariant quadratic state function. A modeling in terms of stochastic Langevin equation is discussed and the relevance of our results in the framework of Space Weather studies is outlined.
214 29 - PublicationOpen AccessHigh resolution magnetic anomalies, volcanism and tectonics of the active “La Fossa” vulcanic system (Vulcano island) and Lipari island (South Italy)In this paper we present the new high-resolution magnetic anomaly map of the La Fossa Caldera system and Lipari island (Southern Italy), obtained by merging two low-altitude aeromagnetic surveys. In these islands a variegated ensemble of magnetic anomalies develops in the north-south direction. The La Fossa Caldera is characterized by very high-intensity and short-wavelength magnetic anomalies, related to mafic intrusive/effusive sources, mainly aligned along the NNW-SSE and NS faults. Instead, the Lipari island is characterized by lower intensity anomalies related to sources with more evolved chemistry, elongated in the NE-SW, NNE-SSW and EW of the subordinate faults. Both the two sets of structures belong to the Tindari-Letojanni strike slip fault-system, a regional lineament along which the southern side of the Aeolian Archipelago is emplaced. The study identifies three distinctive magnetic zones on the Lipari island: the southern, the central, and the north-western ones. The southern zone is characterized by negative magnetic monopoles in correspondence with the younger rhyolitic domes and a Curie Isotherm upwelling. The central part of the island has an average lower intensity of positive anomalies, corresponding to the less evolved products of the intermediate Lipari volcanic epochs. The north-western side is characterized by higher intensity anomalies related to older volcanic epochs. The interplay among strike-slip tectonics, chemistry of the uprising magmas, and the thermal setting has contributed to the overall anomaly pattern in this sector of the Aeolian Archipelago. This interpretation is supported by the application of digital enhancement to the total intensity magnetic anomaly field and by the spatial correlation analysis of the magnetic and volcano-tectonic features. The obtained insights are useful to better understand the relationship between arc volcanism and tectonics. Moreover, they can also outline new inferences to forecast future eruptions of the active La Fossa volcanic system. In fact, recent unrest signals were registered at La Fossa Cone, which is one of the present-day active volcanoes of the Aeolian Archipelago, along with Stromboli island.
132 17 - PublicationOpen AccessBoundaries of magnetic anomaly sources in the Tyrrhenian region(1998-08)
; ; ; ; ;Cella, F.; Dipartimento di Geofisica e Vulcanologia, Universitá di Napoli ;Fedi, M.; Dipartimento di Geofisica e Vulcanologia, Universitá di Napoli ;Florio, G.; Dipartimento di Geofisica e Vulcanologia, Universitá di Napoli "Federico II", Napoli, Italy ;Rapolla, A.; Dipartimento di Geofisica e Vulcanologia, Universitá di Napoli "Federico II", Napoli, Italy; ; ; Analysis of the analytic signal of the aeromagnetic field in the Tyrrhenian region allowed the systematic location of the boundaries of magnetic shallow sources. This method was chosen because of its independence from the magnetization and inducing field direction, and the results were similar to those of the boundary analysis of the horizontal gradient of the pseudogravity transformed field. The analytic signal was computed by a stable algorithm based on the second order horizontal derivatives of the field and Laplace equation. The complexity of the investigated area is well reflected in the aeromagnetic field and an objective and systematic study, such as boundary analysis, provided a rather complete description of the main regional structures. Significant trends indicated the existence of structures, whose nature was still unknown or uncertain. These included structures located between the Vavilov and De Marchi seamounts, NW of Stromboli Island, south of Ponza Island, a buried horst immediately south of the Cilento coastline, a body located northwest of the Cassinis seamount and other small magnetized structures located south of the Tuscanian archipelago. In many cases, a better definition of several structures previously recognized was obtained as in the case of some tectonic alignments (e.g., the Elba ridge, the Romolo and Selli lines, etc.), a large number of igneous seamounts (e.g., Magnaghi, Marsili, Vavilov, Anchise, Quirra, Enarete, Eolo and Sisifo seamounts) and several crystalline outcrops (e.g., Ichnusa, Vercelli, M. della Rondine, Tiberino, Cassinis, Traiano, Glauco and Augusto seamounts).645 588 - PublicationOpen AccessGEOQUEST TROPOMAG DIGITAL ADVENTURE PATH: WHEN SCIENCE IS A GAME(inScience Press, Rua Tomas Ribeiro, 45, 1º D, 1050-225 Lisboa, Portugal, 2023-06-24)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; Game is a powerful educational tool able to involve students and keep their attention high, promoting cognitive development, discoveries, reasoning, and thinking. It is also an effective active form of learning which consolidates the acquired knowledge and carries out an authentic assessment through reality tasks and immediate feedback typical of the use of the digital games. Our gamy-learning experimentation focuses on new methods and practices of science communication, with the aim to face the challenge of educating about natural risks and climate change. The goal is to facilitate the automatic choice of good practices, by stimulating mind, intuition and logic in the perspective of teambuilding in school-based civic education. The proper application of technological tools is a valuable aid for conscious communication for the next generation. A Computer Supported Collaborative Learning Education is experienced, in order to test the efficacy of our GeoQuest TROPOMAG digital adventure, and pave the ground for the implementation of the storytelling in an integrated table game. Our climate change role-playing videogame explores phenomena related to the possible effects of changes in the Earth's magnetic field on the atmosphere. The virtual adventure path is played on smartphones and follows alternative paths chosen by the players to develop the storytelling. As a result, students play not only “just for fun”, but also to actively participate in their learning process and acquisition of new knowledge, skills and competences in environmental issues.61 16 - PublicationRestrictedThe Hungarian Magnetic Network and the Processing of the Obtained Data(1999)
; ; ; ; ; ;Kovács, P.; Eötvös Loránd Geophysical Institute, H-1440 Budapest, POB 35 Hungary ;Körmendi, L.; Eötvös Loránd Geophysical Institute, H-1440 Budapest, POB 35 Hungary ;Hegymegi, L.; titute, H-1440 Budapest, POB 35 Hungary ;Chiappini, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Dominici, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; ; ; ; In 1994-95 a geomagnetic survey was carried out on the territory of Hungary and the neighbouring regions on 195 stations. Magnetic declination, inclination and total field were directly observed. Some of the stations were measured jointly with Istituto Nazionale di Geofisica (ING), Roma. The results were reduced to the epoch of 1995.0. Normal fields for the magnetic components were determined as second order functions of the geographic coordinates. The polynomial coefficients have been computed in three different waves: by means of simple and weighted least squares procedure and using the adjustment according to "most frequent value". In the present paper the mathematical foundation of these methods and the comparison between the obtained results will be presented.223 29 - PublicationOpen AccessClearance Operation of Teulada Site (Italy): A Novel Approach for Short Term MCM Missions in Seafloor Hard Conditions(2008-06-10)
; ; ; ; ; ;Di Gennaro, E.; CSSN (Centro Supporto e Sperimentazione Navale) - Italian Navy, Viale San Bartolomeo, 400 - 19138 La Spezia, Italy ;Bovio, E.; NURC - A Nato Research Centre, Viale San Bartolomeo, 400 - 19138 La Spezia, Italy ;Baralli, F.; NURC - A Nato Research Centre, Viale San Bartolomeo, 400 - 19138 La Spezia, Italy ;Faggioni, O.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Soldani, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; ; ; ; ; UDT Europe ConferencesIn May 2007, following a request by Italian Navy (ITN), NURC agreed to provide the technology, developed during the port protection studies and 2006 MCM ops. in Baltic sea for Estonian Navy, to survey part of the Capo Teulada firing range (Sardinia Island, Italy), used by NATO Armed Forces. The goal of the service, fully funded by ITN, was to survey part of the firing range with acoustic, magnetic and optical instruments in order to detect and classify the ordnance laying on the seafloor. The team operated from CRV Leonardo to produce a detailed acoustic and magnetic map of the area. The positions of the targets of interest have been provided to Italian Navy for further identification and disposal. The activities have demonstrated that the NURC Autonomous Underwater Vehicles (AUVs) Remus type equipped with high frequency side scan sonar can detect and classify targets of the dimensions of unexploded ordnance laying proud on the sea floor. A multiple sonar images technique has also been used to improve the classification performances. However, in some areas, targets that were completely buried or concealed in Posidonia fields wouldn’t have been detectable with AUV sonar. To overcome this limitation, INGV supported the NURC team by using a new high definition magnetometer technique to detect and classify buried metal targets. A proton Overhauser sensor was towed from Leonardo vessel and a magnetometer reference station was set ashore in an appropriate site. A subset of interesting contacts (acoustic and magnetic) have been identified optically by means of the video camera installed on the ROV (Pluto Plus type by Gaymarine) operated from Leonardo. The positioning accuracy achieved was fully compatible with the reacquisition by ROV and then by divers or mine hunters for future disposal ops. The survey has also produced an accurate map of the Posidonia fields and a detailed bathymetry of the area. More than 300 contacts have been acquired and more than 200 were classified in less than 15 days. The success of Teulada operation has convinced ITN to ask NURC for a common development programme with the aim to validate at sea a fully integrated multi-sensor approach (sonar, magnetic and optical) in MCM short term ops. using USV/AUV platforms.268 4764 - PublicationOpen AccessGeomagnetic observation result, 2006-2007(2008)
; ; ; ; ; ; ; ;Cafarella, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Lepidi, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Meloni, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Palangio, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Pietrolungo, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Santarelli, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;ZIrizzotti, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; ; ; ; ; ; 179 65 - PublicationRestrictedUltra-thick Triassic dolomites control the rupture behavior of the central Apennine seismicity: Evidence from magnetic modeling of the L’Aquila fault zone(2014)
; ; ;Speranza, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Minelli, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; High-resolution tomography from the 2009 L’Aquila extensional seismic sequence has shown that the Mw 6.1 main shock and most of the aftershocks occurred within a high velocity body (6.6≤Vp≤6.8 Km/s), located between depths of 3 and 12 km. The nature of the high Vp-body has remained speculative, although exhumed mafic deep crustal and upper mantle rocks (serpentinites) have been favoured. We used 3D magnetic anomaly modelling to investigate the plausibility of these favoured sources for the L’Aquila body. The modelling does not support the presence of high-velocity serpentinites with a 30-50% serpentinization degree and gabbros. Accordingly, we conclude that the high Vp-body may represent non-magnetic upper Triassic and possibly lower Liassic dolomites that have been drilled in neighbouring wells for 2-4 km. This conclusion is also consistent with the lack of a coherent gravity anomaly for the body. We speculate that ultra-thick Triassic dolomites reaching a thickness of 8 km may have been deposited in syntectonic wedges formed at the northern margin of the Ionian Sea, where oceanic spreading occurred in mid-late Triassic times.398 71