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Insight into ground deformations at Lascar volcano (Chile) from SAR interferometry, photogrammetry and GPS data: Implications on volcano dynamics and future space monitoring / A. Pavez in Remote sensing of environment, vol 100 n° 3 (15 february 2006)  

Public [article]  inRemote sensing of environment > vol 100 n° 3 (15 february 2006) . - pp 307 - 320 Titre : Insight into ground deformations at Lascar volcano (Chile) from SAR interferometry, photogrammetry and GPS data: Implications on volcano dynamics and future space monitoring Type de document : Article/Communication Auteurs : A. Pavez, Auteur ; D. Remy, Auteur ; Sylvain Bonvalot, Auteur ; Michel Diament , Auteur ; G. Gabalda, Auteur ; J.L. Froger, Auteur ; Patrick Julien , Auteur ; D. Legrand, Auteur ; Didier Moisset , Auteur Année de publication : 2006 Article en page(s) : pp 307 - 320 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques [Termes IGN] analyse diachronique [Termes IGN] Chili [Termes IGN] déformation de la croute terrestre [Termes IGN] données de terrain [Termes IGN] données GPS [Termes IGN] image aérienne [Termes IGN] image radar moirée [Termes IGN] interféromètrie par radar à antenne synthétique [Termes IGN] surveillance géologique [Termes IGN] volcan Résumé : (Auteur) We present a detailed study of Lascar volcano (Chile) based on the combination of satellite, aerial and ground-based data, in order (i) to better characterize the deformation style of Andean explosive volcanoes, and (ii) to provide new insights on the potential of space techniques to monitor active volcanic deformations on such edifices. Lascar is one of the most active volcanoes in Central Andes characterized by a recent cyclic activity. Additionally, it is located in favourable conditions for radar imaging. Lascar thus offers very good conditions for studying large to, small scale ground deformations associated with volcano dynamics. The analysis of InSAR (Synthetic Aperture Radar interferometry) time series data from the European and Japanese satellites (ERS, JERS) acquired between 1993 and 2000, encompassing three eruptive events, confirmed the absence of broad far-field deformation signal. Thus during the recent activity of Lascar we discard significant magmatic input at depth. The following approaches were used to improve the InSAR signal/noise ratio in order to detect possible local deformation. We carried out a quantitative evaluation of the potential tropospheric contribution in INSAR interferograms for the Salar de Atacama-Lascar area using radar (ASAR-ENVISAT) and spectrometer (MODIS) data. We also used an accurate aerial photogrammetric and GPS constrained DEM in our InSAR data reprocessing. We find a co-eruptive ground-deformation confined into the summit crater for the 1995 eruption. This deformation bas spatial dimension of 500 by 400 m and relates to a subsidence of crater floor up to 17 mm. We interpret it as pressure or volume decrease at subsurface levels below the active crater. Our study made it possible to image a new near-field volcanic deformation confined within the summit crater of the Lascar volcano. It also demonstrates that the combination of precise photogrammetry DEM and INSAR data can significantly improve our ability to, rernotely sense subtle surface deformation on these explosive volcanoes. This methodology might contribute to, better understand volcano dynamics and to complement their monitoring in remote areas. Numéro de notice : A2006-035 Affiliation des auteurs : MATIS+Ext (1993-2011) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2005.10.013 Date de publication en ligne : 13/12/2005 En ligne : https://doi.org/10.1016/j.rse.2005.10.013 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27762 [article]