HR: 09:45h
AN: G41A-08    [Abstracts]
TI: iGeoPS©, a Matlab tool for High Rate GPS data analysis: application to the Mt.Etna network
AU: Mattia, M
EM: mattia@ct.ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, Piazza Roma 2, catania, 95123, Italy
AU: * Cannavò, F
EM: fla@interfree.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, Piazza Roma 2, catania, 95123, Italy
AU: Rossi, M
EM: rossi@ct.ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, Piazza Roma 2, catania, 95123, Italy
AU: Russo, G
EM: quantumverghe@jumpy.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, Piazza Roma 2, catania, 95123, Italy
AB: In these last years, an increasing interest in high rate GPS is clearly showed by the numbers of papers where this methodology is applied in seismology (Larson et al., 2003; Bock and Prawirodirdjo, 2004; Ji et al., 2004; Miyazaki et al., 2004; Elosegui et al., 2006.), in volcanology (Mattia et al., 2004), and in tsunami hazard evaluation (Blewitt et al., 2006). Sometime this technique is applied in "a posteriori", meaning that the data collected by the GPS stations are reprocessed and analysed, but the great potential of HRGPS is surely related to its application in the field of real time processing and to the big interest of the civil protection authorities in following dynamic processes related, for example, to the opening of a fracture field or to a dome extrusion during a volcanic eruption. Since 2002, the INGV (Istituto Nazionale di Geofisica e Vulcanologia) section of Catania (Italy) manage two real time high rate GPS networks in Stromboli and Etna volcanoes. In order to improve our capability to evaluate the volcanic risk and our knowledge of the deformative processes linked to magma movements at shallow depths, we developed a software tool finalised to the analysis of HRGPS data. This software tool, named iGeoPS©, runs in Matlab© framework and permits to analyze long series of HRGPS data sampled with any frequency. In particular, the tool can visualize raw data, statistically filter the raw data, sidereally filter the data, calculate power spectrum for specified windows (both in time and frequency content), display spectrograms of the signal, calculate statistics and RMS of the scatter of the data, and perform cross-correlation and trend analysis for different series. Moreover, iGeoPS© allows to do advanced non linear analysis such as fractal and chaotic analysis and integrates different non linear modelling techniques such as neural networks, fuzzy systems and wavelets. In this paper, after a brief introduction to the features of the developed tool, we summarize the main results related to the characteristics of the HRGPS signal and to the main volcanic events observed using this approach. Furthermore we show an analysis of data collected since 2003 on Mt.Etna where phenomena related to explosive activity, opening of fractures, tidal effects etc, clearly define the potential of this technique in volcano monitoring.
DE: 1241 Satellite geodesy: technical issues (6994, 7969)
DE: 1294 Instruments and techniques
DE: 8419 Volcano monitoring (7280)
DE: 8488 Volcanic hazards and risks
SC: Geodesy [G]
MN: 2007 Joint Assembly