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Giannone, Francesca
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- PublicationRestrictedSpace geodesy validation of the global lithospheric flow(2006)
; ; ; ; ; ;Crespi, C.; DITS – Area di Geodesia e Geomatica, Universit`a di Roma ‘La Sapienza’, Roma. ;Cuffaro, M.; Dipartimento di Scienze della Terra, Universit`a di Roma ‘La Sapienza’, Roma. ;Doglioni, C.; Dipartimento di Scienze della Terra, Universit`a di Roma ‘La Sapienza’, Roma. ;Giannone, F.; DITS – Area di Geodesia e Geomatica, Universit`a di Roma ‘La Sapienza’, Roma. ;Riguzzi, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; ; ; ; Space geodesy data are used to verify whether plates move chaotically or rather follow a sort of tectonic mainstream. While independent lines of geological evidence support the existence of a global ordered flow of plate motions that is westerly polarized, the Terrestrial Reference Frame (TRF) presents limitations in describing absolute plate motions relative to the mantle. For these reasons we jointly estimated a new plate motions model and three different solutions of net lithospheric rotation. Considering the six major plate boundaries and variable source depths of the main Pacific hotspots, we adapted the TRF plate kinematics by global space geodesy to absolute plate motions models with respect to the mantle. All three reconstructions confirm (i) the tectonic mainstream and (ii) the net rotation of the lithosphere. We still do not know the precise trend of this tectonic flow and the velocity of the differential rotation. However, our results show that assuming faster Pacific motions, as the asthenospheric source of the hotspots would allow, the best lithospheric net rotation estimate is 13.4 ± 0.7 cm yr−1. This superfast solution seems in contradiction with present knowledge on the lithosphere decoupling, but it matches remarkably better with the geological constraints than those retrieved with slower Pacific motion and net rotation estimates. Assuming faster Pacific motion, it is shown that all plates move orderly ‘westward’ along the tectonic mainstream at different velocities and the equator of the lithospheric net rotation lies inside the corresponding tectonic mainstream latitude band (≈±7◦), defined by the 1σ confidence intervals.300 29 - PublicationOpen AccessTowards a satellite-based approach to measure eruptive volumes at Mt. Etna using Pleiades datasets(2020-03-30)
; ; ; ; ; ; ; ; ; ; ; Only a few high precision studies of lava and tephra during simultaneous explosive and effusive activity have so far been undertaken. We carried out such measurements by analysis of a unique and homogeneous multi-temporal dataset of highspatial resolution satellite optical images. Digital Elevation Models (DEMs) and orthophotos (with 1- and 0.5-m-pixel resolutions respectively) were extracted from six specifically tasked Pleiades tri-stereo pairs of Mt. Etna volcano, between 2011 and 2016. During this period, frequent effusive and explosive events formed lava flow fields and built up the new south-east crater pyroclastic cone. The volumes of lava fields and proximal pyroclastic deposits were measured by comparing the Pleiades DEMs with an aerial photogrammetric DEM updated in 2007. The volumes of all distal deposits were estimated using lava and tephra partitioning from the literature for an Etnean lava fountain. The dense rock equivalent volume of lava and tephra, calculated to be 248.4 ± 2.1 × 106 m3 in total, corresponds to an average output rate of 0.98 m3/s over the analysed 8-year period (May 2008–May 2016) and to a multi-event eruption rate of 5.53 m3/s for 520 days of activity. The multi-temporal analysis of high-spatial resolution satellite DEMs, here successfully applied to the well-monitored Etna volcano, demonstrated that the tasking of high-spatial resolution satellite images is crucial for fast and effective monitoring during intense volcanic activity (frequent and overlapping eruptive events). This methodology could be used for the monitoring of remote or hazardous volcanoes that are difficult to study by means of repeated field surveys.362 73 - PublicationOpen AccessA model of plate motion(2006)
; ; ; ; ; ;Riguzzi, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia ;Crespi, M.; University La Sapienza, Rome, Italy ;Cuffaro, M.; University La Sapienza, Rome, Italy ;Doglioni, C.; University La Sapienza, Rome, Italy ;Giannone, F.; University La Sapienza, Rome, Italy; ; ; ; The wide use of space geodesy techniques devoted to geophysical and geodynamical purposes has recently evidenced some limitations due to the intrinsic Terrestrial Reference Frame (TRF) definition. Current TRFs are defined under hypotheses suited to overcome the rank deficiency of the observations with respect to the parameters that have to be estimated, i.e. coordinates and velocities (Dermanis, 2001; Dermanis, 2002). From a geodetic point of view, one possibility implies the application of the no-net-rotation condition (NNR). One of the main geophysical consequences due to the application of this condition is that it allows only accurate estimations of relative motions, whilst other motions of geodynamical interest, for instance with respect to the inner layers of the Earth body, are not determinable. The main purpose of this paper is to propose a unified way to describe plate motions, overcoming the problems introduced by the NNR condition, in order to establish a new reference frame useful for geodynamical applications too. Since we believe relevant the role played by global tectonics inferences, we introduce the concept of the main tectonic sinusoid to propose an analytical description of the plate motions flow, which is polarized to the “west” in the hotspot reference frame.160 271 - PublicationOpen AccessStudio delle possibilità di utilizzo della costellazione Glonass nel suo stato(2006)
; ; ; ;Baiocchi, V.; DITS - Area di Geodesia e Geomatica, Università di Roma "La Sapienza", via Eudossiana, 18 - 00184 Roma ;Giannone, F.; DITS - Area di Geodesia e Geomatica, Università di Roma "La Sapienza", via Eudossiana, 18 - 00184 Roma ;Pietrantonio, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; ; GLONASS (Global Navigation Satellite System) is a global position satellite system realized by ex- Urss at the same time with the United State’s one. The first launch of satellites went back to 12th October 1982, they completed constellation with 24 satellites in 1997. In the years Russia didn’t have economic force to maintain active the entire constellation. But in 2002 GLONASS relaunching started, that provides 18 satellites before 2007, and it will reach 24 satellites before 2010. The program provides the launch of three or two rockets a year, each one will bring to space two or three satellite. At present (15th September 2006) there are 15 operative GLONASS satellites. The aim of this work is to show the potentiality of the jointed use of GPS and GLONASS satellites by performing an adequate subdivision of the observations collected during a survey in the area of Rome using TOPCON receivers able to acquire data coming from both constellations.126 288 - PublicationRestrictedMonitoring an active volcanic area and mapping lava flows with multisource data: The case of Mount Etna from 2011 to 2015(2016-06)
; ; ; ; ; ; ; ; ;Martino, M.; DICEA, La Sapienza University, Roma, Italy ;Marsella, M.; DICEA, La Sapienza University, Roma, Italy ;Scifoni, S.; DICEA, La Sapienza University, Roma, Italy ;Coltelli, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Proietti, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia ;Chowdhury, T.A.; DLR, Weßling, Germany ;Minet, C.; DLR, Weßling, Germany ;Giannone, F.; Niccolò Cusano University, Roma, Italy; ; ; ; ; ; ; The ground monitoring of an active volcanic area presents many complexities. By exploiting the remote sensing techniques, we developed an analytical methodology for observing and quantifying eruptive processes and the related phenomena (lava flows, volcanic avalanche/landslides, slope stability features). This methodology integrates HR optical images and SAR interferometry, acquired in different time frames and was tested on the case study of Mount Etna. The extraction of new cartographic products allows us to define the volcanic hazards that may impact on the surrounding populated areas and infrastructures.94 18