http://hdl.handle.net/2122/206 2013-05-18T23:53:30Z http://hdl.handle.net/2122/8554 Title: GPS observations of coseismic deformation following the May 20 and 29, 2012, Emilia seismic events (northern Italy): data, analysis and preliminary models Authors: Serpelloni, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Anderlini, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Avallone, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Cannelli, V.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Cavaliere, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Cheloni, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; D'Ambrosio, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; D'Anastasio, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Esposito, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Pietrantonio, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Pisani, A. R.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Anzidei, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Cecere, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; D'Agostino, N.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Del Mese, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Devoti, R.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Galvani, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Massucci, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Melini, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Riguzzi, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Selvaggi, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Sepe, V.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia Abstract: In May-July 2012, a seismic sequence struck a broad area of the Po Plain Region in northern Italy. The sequence in- cluded two ML >5.5 mainshocks. The first one (ML 5.9) oc- curred near the city of Finale Emilia (ca. 30 km west of Ferrara) on May 20 at 02:03:53 (UTC), and the second (ML 5.8) occurred on May 29 at 7:00:03 (UTC), about 12 km south- west of the May 20 mainshock (Figure 1), near the city of Mirandola. The seismic sequence involved an area that ex- tended in an E-W direction for more than 50 km, and in- cluded seven ML ≥5.0 events and more than 2,300 ML >1.5 events (http://iside.rm.ingv.it). The focal mechanisms of the main events [Pondrelli et al. 2012, Scognamiglio et al. 2012, this volume] consistently showed compressional kinematics with E-W oriented reverse nodal planes. This sector of the Po Plain is known as a region charac- terized by slow deformation rates due to the northwards mo- tion of the northern Apennines fold-and-thrust belt, which is buried beneath the sedimentary cover of the Po Plain [Pi- cotti and Pazzaglia 2008, Toscani et al. 2009]. Early global po- sitioning system (GPS) measurements [Serpelloni et al. 2006] and the most recent updates [Devoti et al. 2011, Bennett et al. 2012] recognized that less than 2 mm/yr of SW-NE short- ening are accommodated across this sector of the Po Plain, in agreement with other present-day stress indicators [Mon- tone et al. 2012] and known active faults [Basili et al. 2008]. In the present study, we describe the GPS data used to study the coseismic deformation related to the May 20 and 29 mainshocks, and provide preliminary models of the two seismic sources, as inverted from consensus GPS coseismic deformation fields. 2011-12-31T23:00:00Z http://hdl.handle.net/2122/8550 Title: New kinematic constraints of the western Doruneh fault, north-eastern Iran, from interseismic deformation analysis Authors: Pezzo, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Tolomei, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Atzori, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Salvi, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Shabanian, E.; CEREGE - AIX-MARSEILLE UNIVERSITE; Bellier, O.; CEREGE - AIX-MARSEILLE UNIVERSITE; Farbod, Y.; CEREGE - AIX-MARSEILLE UNIVERSITE Abstract: We used the SBAS DInSAR analysis technique to estimate the interseismic deformation along the western part of the Doruneh fault system (DFS), northeastern Iran. We processed 90 ENVISAT images from four different frames from ascending and descending orbits. Three of the ground velocity maps show a significant interseismic signal. Using a simple dislocation approach we model 2-D velocity profiles concerning three InSAR data set relative to the western part of the DFS, obtaining a good fit to the observations. The resulting model indicates that a slip rate of ∼5mmyr−1 accumulates on the fault below 10 km depth, and that in its western sector the Doruneh fault is not purely strike-slip (left-lateral) as in its central part, but shows a significant thrust component. Based on published geological observations, and assuming that all interseismic deformation is recovered with a single event, we can estimate a characteristic recurrence interval between 630 and 1400 yr. 2012-05-20T22:00:00Z http://hdl.handle.net/2122/8549 Title: Reassessment of the source of the 1976 Friuli, NE Italy, earthquake sequence from the joint inversion of high-precision levelling and triangulation data Authors: Cheloni, D.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; D'Agostino, N.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; D'Anastasio, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Selvaggi, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia Abstract: In this study, we revisit the mechanism of the 1976 Friuli (NE Italy) earthquake sequence (main shocks M w 6.4, 5.9 and 6.0). We present a new source model that simultaneously fits all the available geodetic measurements of the observed deformation. We integrate triangulation measurements, which have never been previously used in the source modelling of this sequence, with high-precision levelling that covers the epicentral area. We adopt a mixed linear/non-linear optimization scheme, in which we iteratively search for the best-fitting solution by performing several linear slip inversions while varying fault location using a grid search method. Our preferred solution consists of a shallow north-dipping fault plane with assumed azimuth of 282◦ and accommodating a reverse dextral slip of about 1 m. The estimated geodetic moment is 6.6 × 1018 Nm (M w 6.5), in agreement with seismological estimates. Yet, our preferred model shows that the geodetic solution is consistent with the activation of a single fault system during the entire sequence, the surface expression of which could be associated with the Buia blind thrust, supporting the hypothesis that the main activity of the Eastern Alps occurs close to the relief margin, as observed in other mountain belts. The retrieved slip pattern consists of a main coseismic patch located 3–5 km depth, in good agreement with the distribution of the main shocks. Additional slip is required in the shallower portions of the fault to reproduce the local uplift observed in the region characterized by Quaternary active folding. We tentatively interpret this patch as postseismic deformation (afterslip) occurring at the edge of the main coseismic patch. Finally, our rupture plane spatially correlates with the area of the locked fault determined from interseismic measurements, supporting the hypothesis that interseismic slip on the creeping dislocation causes strain to accumulate on the shallow (above ∼10 km depth) locked section. Assuming that all the long-term accommodation between Adria and Eurasia is seismically released, a time span of 500–700 years of strain-accumulating plate motion would result in a 1976-like earthquake. 2011-12-31T23:00:00Z http://hdl.handle.net/2122/8526 Title: The stress field in Europe: optimal orientations with confidence limits Authors: Carafa, M. M. C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Barba, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia Abstract: In this study, we modify and extend a data analysis technique to determine the stress orientations between data clusters by adding an additional constraint governing the probability algorithm. We apply this technique to produce a map of the maximum horizontal compressive stress (S_Hmax) orientations in the greater European region (including Europe, Turkey and Mediterranean Africa). Using the World Stress Map dataset release 2008, we obtain analytical probability distributions of the directional differences as a function of the angular distance, θ. We then multiply the probability distributions that are based on pre-averaged data within θ<3° of the interpolation point and determine the maximum likelihood estimate of the S_Hmax orientation. At a given distance, the probability of obtaining a particular discrepancy decreases exponentially with discrepancy. By exploiting this feature observed in the World Stress Map release 2008 dataset, we increase the robustness of our S_Hmax determinations. For a reliable determination of the most likely S_Hmax orientation, we require that 90% confidence limits be less than ±60° and a minimum of three clusters, which is achieved for 57% of the study area, with small uncertainties of less than ±10° for 7% of the area. When the data density exceeds 0.8×10^-3 data/km2, our method provides a means of reproducing significant local patterns in the stress field. Several mountain ranges in the Mediterranean display 90° changes in the S_Hmax orientation from their crests (which often experience normal faulting) and their foothills (which often experience thrust faulting). This pattern constrains the tectonic stresses to a magnitude similar to that of the topographic stresses. Description: This article has been accepted for publication in Geophysical Journal International ©: The Authors 2003. Published by Oxford University Press on behalf of The Royal Astronomical Society. All rights reserved. 2012-12-31T23:00:00Z http://hdl.handle.net/2122/8515 Title: Vent temperature trends at the Vulcano Fossa fumarole field: the role of permeability Authors: Harris, A.; Laboratoire Magmas et Volcans, Université Blaise Pascal; Alparone, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Bonforte, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Dehn, J.; University of Alaska Fairbanks; Gambino, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Lodato, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Spampinato, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia Abstract: Between 1994 and 2010, we completed 16 thermal surveys of Vulcano’s Fossa fumarole field (Aeolian Islands, Italy). In each survey, between 400 and 1,200 vent temperatures were collected using a thermal infrared thermometer from distances of ∼1 m. The results show a general decrease in average vent temperature during 1994–2003, with the average for the entire field falling from ∼220°C in 1994 to ∼150°C by 2003. However, between 2004 and 2010, we witnessed heating, with the average increasing to ∼190°C by 2010. Alongside these annual-scale field-wide trends, we record a spatial re-organisation of the fumarole field, characterised by shut down of vent zones towards the crater floor, matched by rejuvenation of zones located towards the crater rim. Heating may be expected to be associated with deflation because increased amounts of vaporisation will remove volume from the hydrothermal system Gambino and Guglielmino (J Geophys Res 113: B07402, 2008). However, over the 2004–2010 heating period, no ground deformation was observed. Instead, the number of seismic events increased from a typical rate of 37 events per month during 1994–2000 to 195 events per month during 2004–2010. As part of this increase, we noticed a much greater number of high-frequency events associated with rock fracturing. We thus suggest that the heating event of 2004–2010 was the result of changed permeability conditions, rather than change in the heat supply from the deeper magmatic source. Within this scenario, cooling causes shut down of lower sectors and re-establishment of pathways located towards the crater rim, causing fracturing, increased seismicity and heat flow in these regions. This is consistent with the zone of rejuvenation (which lies towards and at the rim) being the most favourable location for fracturing given the stress field of the Fossa cone Schöpa et al. (J Volcanol Geotherm Res 203:133–145, 2011); it is also the most established zone, having been active at least since the early twentieth century. Our data show the value of deploying multi-disciplinary geophysical campaigns at degassing (fumarolic) hydrothermal systems. This allows more complete and constrained understanding of the true heat loss dynamics of the system. In the case study presented here, it allows us to distinguish true heating from apparent heating phases. While the former are triggered from the bottom-up, i.e. they are driven by increases in heat supply from the magmatic source, the latter are triggered from the top-down, i.e. by changing permeability conditions in the uppermost portion of the system to allow more efficient heat flow over zones predisposed to fracturing. 2011-12-31T23:00:00Z http://hdl.handle.net/2122/8514 Title: A multidisciplinary study of an active fault crossing urban areas: The Trecastagni Fault at Mt. Etna (Italy) Authors: Bonforte, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Carnazzo, A.; Provincia Regionale di Catania; Gambino, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Guglielmino, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Obrizzo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione OV, Napoli, Italia; Puglisi, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia Abstract: The Trecastagni Fault is a NNW–SSE tectonic structure in the densely inhabited southern flank of Mt. Etna, characterised by evident morphological scarps and movements of normal and right-lateral type that directly affect roads and buildings. The fault is affected by continuous dynamics with intermittent accelerations accompanied with shallow seismicity. It has an important role in the instability affecting Mt. Etna's south-eastern flank and represents part of the southern boundary of the unstable sector. The motion of the fault between 2005 and 2011 has been analysed by using a multi-disciplinary approach involving terrestrial and satellite ground deformation data. Active monitoring systems able to investigate the fault in detail are extensometers, a levelling network and InSAR. Two episodes of acceleration were recorded at the end of 2009 and during 2010. Data evidences that the acceleration episodes affected only portions of the fault and that stress may accumulate and be periodically released. Although bothmagmatic processes (inflation or intrusive episodes) and flank dynamics influence the occurrence of the TF acceleration episodes, the dragging effect of the overall seaward sliding of the south-eastern flank is evident and it causes the subsidence of the hangingwall, accumulating stress on the fault that is periodically seismically released. 2012-12-31T23:00:00Z http://hdl.handle.net/2122/8508 Title: Red GPS Topo-Iberia: Resultados Preliminares obtenidos en el Centro de Análisis de la UJA Authors: Gil, A. J.; Dpto. Ingeniería Cartográfica, Geodésica y Fotogrametría. Universidad de Jaén. España; de Lacy, M. C.; Dpto. Ingeniería Cartográfica, Geodésica y Fotogrametría. Universidad de Jaén. España; Ruiz, A. M.; Dpto. Ingeniería Cartográfica, Geodésica y Fotogrametría. Universidad de Jaén. España; Armenteros, J. A.; Dpto. Ingeniería Cartográfica, Geodésica y Fotogrametría. Universidad de Jaén. España; Adan, R.; Dpto. Ingeniería Cartográfica, Geodésica y Fotogrametría. Universidad de Jaén. España; Aviles, A.; Dpto. Ingeniería Cartográfica, Geodésica y Fotogrametría. Universidad de Jaén. España; Riguzzi, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Devoti, R.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia Abstract: The project “Geociencias en Iberia: Estudios integrados de topografía y evolución 4D: Topo-Iberia” (Ref.CSD2006- 00041) is supported by the Spanish Ministry of Economy and Competitiveness. Its objective is to understand the interactions in the Iberian Peninsula (SW Europe) between deep, shallow and atmospheric processes, through a multidisciplinary approach linking Geology, Geophysics and Geodesy. As part of this project a network of 26 continuous GPS stations, covering the Spanish part of the Iberian Peninsula (22 stations) and Morocco (4 stations) has been established. The major objective behind the establishment of this array is to monitor millimetre level deformation of the crust due to Nubia and Eurasian tectonic plates. More specific goals of the project include the identification of the areas and/or specific seismic faults which exhibit higher deformation rates, which could imply an increased seismic hazard in these specific areas. In December 2008, the network installation was completed and all the stations were fully operational. Data analysis is performed at three different analysis centres: Real Instituto y Observatorio de la Armada (ROA), University of Barcelona (UB) and University of Jaen (UJA). Different approaches to processing GPS data by using different software are being carried out. The first coordinate time series and the velocity field computed so far at UJA analysis centre are presented 2012-06-24T22:00:00Z http://hdl.handle.net/2122/8496 Title: Are the source models of the M7.1 1908 Messina Straits earthquake reliable? Insights from a novel inversion and a sensitivity analysis of levelling data Authors: Aloisi, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Bruno, V.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Cannavo', F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Ferranti, L.; Dipartimento di Scienze della Terra, Universita' di Napoli; Mattia, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Monaco, C.; Dipartimento di Scienze Geologiche, Universita' di Catania; Palano, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia Abstract: For decades, many authors have attempted to define the location, geometry and kinematics of the causative fault for the 1908 December 28, M 7.1 earthquake that struck the Messina Straits between Sicily and Calabria (southern Italy). The coseismic displacement caused a predominant downwarping of the Straits and small land uplift away from it, which were documented by levelling surveys performed 1 yr before and immediately after the earthquake. Most of the source models based on inversion of levelling data suggested that the earthquake was caused by a low angle, east-dipping blind normal fault, whose upper projection intersects the Earth surface on the Sicilian (west) side of the Messina Straits.An alternative interpretation holds that the causative fault is one of the high-angle, west-dipping faults located in southern Calabria, on the eastern side of the Straits, and may in large part coincide with the mapped Armo Fault. Here, we critically review the levelling data with the aim of defining both their usefulness and limits in modelling the seismogenic fault. We demonstrate that the levelling data alone are not capable of discriminating between the two oppositely dipping fault models, and thus their role as a keystone for modellers is untenable. However, new morphotectonic and geodetic data indicate that the Armo Fault has very recent activity and is accumulating strain. The surface observations, together with appraisal ofmacroseismic intensity distribution, available seismic tomography and marine geophysical evidence, lends credit to the hypothesis that the Armo and possibly the S. Eufemia faults are part of a major crustal structure that slipped during the 1908 earthquake. 2012-12-31T23:00:00Z http://hdl.handle.net/2122/8453 Title: INTERFÉROMÉTRIE RADAR APPLIQUÉE AUX VOLCANS : CAS DE L’ETNA ET DES CHAMPS PHLÉGRÉENS (ITALIE) Authors: Briole, Pierre; Institut de Physique du Globe de Paris; Avallone, Antonio; Università "Federico II" di Napoli; Beauducel, François; Institut de Physique du Globe de Paris; Bonforte, Alessandro; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia; Cayol, Valerie; Institut de Physique du Globe de Paris; Deplus, Christine; Institut de Physique du Globe de Paris; Delacourt, Christophe; UCBL & ENSL,Lyon; Froger, Jean-Luc; Université de Clermont Ferrand; Malengreau, B.; Université de Clermont Ferrand; Puglisi, Giuseppe; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Catania, Catania, Italia Abstract: During the last few years, the radar images collected by the European satellites ERS1 and ERS2, the Japanese satellite JERS and the Canadian satellite RADARSAT have been used with success to create interferograms. This technique has been applied for geophysical applications like co-seismic deformation mapping, volcano deformation monitoring, landslides monitoring, mining subsidence detection, glaciers monitoring. Here we report the research carried out by our group on Etna volcano (Italy) and in the area of Naples (Italy) where are located several potentially active volcanoes (Vesuvius, Ischia) and where a subsidence of the caldera of Campi Flegrei is still on going in response to the 1982-1984 seismic crisis. Etna is the volcano that has been studied first using ERS SAR interferometry. Using this method, a large scale deflation of the volcano associated with the large 1991-1993 eruption was detected in data covering the second half of the eruption. Further studies showed that the local deformation fields located in Valle del Bove (East of the volcano) where associated with the compaction of the 1986-1987 and 1989 lava fields and also partly with a subsidence of the surrounding terrain in response to the load of the new deposited material. Other local deformation fields have been identified, corresponding to the 1983, 1981 and 1971 lava fields. However, due to its strong topography, interferograms of Etna are affected by tropospheric effects. Those effects must be eliminated in order to correctly interpret the fringes pattern. The problem of the troposphere has been first investigated from its theoretical point of view and using existing local meteorological data as well as radio-soundings data. Recently, thanks to the large amount of available interferograms, another approach has been investigated, consisting in the research of a correlation fringe/elevation in the interferograms themselves. This approach, operated either in automatic mode (automatic fringe unwrapping) or in manual mode proved to be efficient for most of the coherent interferograms. After removal of the tropospheric correction, the evolution of the deformation of the volcano at large scale between 1992 and 1998 has been inferred. The subsidence occurring during the second half of the 1992 eruption as well as the uplift preceding the 1995 unrest of the Southeast crater are visible, but their amplitude is less than previously estimated. The depth of the modelled source of subsidence/uplift related to the large scale deformation is of the order of 6 to 8 km, not well constrained by the data. The study of the correlation fringe/elevation was possible only after a detailed analysis of the spatial and temporal properties of coherence of the Etna area. Indeed, the technique of fringe unwrapping for fringe/elevation correlation analysis is possible only if the poorly coherent pixels are eliminated. A map of the most coherent pixels of the volcano was produced. The recent lava fields as well as the towns and villages surrounding the volcano are the most coherent areas. The quality of the interferograms is also enhanced when high accuracy DEM (Digital Elevation Model) are used. Using kinematic GPS data collected along more than 100 km of road around the volcano, we assessed the accuracy of several DEMs of Etna. The most accurate DEM was produced by digitising 1/25.000e maps of Etna. This DEM does not take into account the topographic changes due to the recent eruptions. Merging other more recent DEMs corresponding to those areas, we produced an updated relatively high accuracy DEM (±3 m) of Etna. In the Naples area, we analysed interferograms in the period 1993-1996 and show that the Campi Flegrei caldera is still subsiding at a rate of about 30 mm/year. 1998-12-31T23:00:00Z http://hdl.handle.net/2122/8448 Title: Acquisition, storage and distribution of data and metadata of the Italian CGPS network (RING) Authors: Cecere, Gianpaolo; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Zarrilli, Luigi; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Pignone, Maurizio; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Moschillo, Raffaele; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Cogliano, Rocco; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Castagnozzi, Angelo; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia; Falco, Luigi; Istituto Nazionale di Geofisica e Vulcanologia, Sezione CNT, Roma, Italia Abstract: In the framework of the development of the “Rete Integrata Nazionale GPS” of the Istituto Nazionale di Geofisica e Vulcanologia, we worked on the acquisition, storage and distribution of the data recorded by the network. We will show problems and solutions that we have faced, from the transmission stage to the final distribution of data and metadata of the recorded observations. In general, we have worked on software solutions to provide a quality check on the observation files that make use of java platform implemented with a front-end software for a rapid graphical time series restitution of common quality parameters as for multipath on L1 and L2, cycle slips and others, that can run easily on any operative system (namely “Clinic”). The observation files, and metadata of the network, are managed by a Knowledge Management infrastructure finalized to the web sharing management. The direct exposure on internet needs to interface all the modifying/querying processes of information contained in the database, by means of a software based on a framework of MVC type (Model View Controller), carried out on a J2EE platform (java2 Enterprise Edition). This system uses JSP (Java Server Page) and Servlet to allow, through HTTP protocol (Hyper Text Transfer Protocol), the management of devices in the field with dynamic HTML pages. A restricted access allows: creation and download of the CGPS log files, creation and download of the site monographic information, operations of files uploading and downloading from/to the central server, site status management and creation of time series plots. A web site, presently under construction but open within 2006, will access to the database and will be complemented with territorial and geographic data elaborated using a Geographical Information System (Ring WebGis). The WebGis is a user-friendly interface for reference territorial and cartographic data and for the development of the CGPS network. The HTML viewer allows the user to interact with geographical data using the common tools of a webgis (interrogation, selection etc.) 2006-09-13T22:00:00Z