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Does long-term GPS in the Western Alps finally confirm earthquake mechanisms? / Andrea Walpersdorf in Tectonics, vol 37 n° 10 (October 2018)  

Public [article]  inTectonics > vol 37 n° 10 (October 2018) . - pp 3721 - 3737 Titre : Does long-term GPS in the Western Alps finally confirm earthquake mechanisms? Type de document : Article/Communication Auteurs : Andrea Walpersdorf, Auteur ; L. Pinget, Auteur ; P. Vernant, Auteur ; C. Sue, Auteur ; A. Deprez, Auteur ; et al., Auteur ; Olivier Bock , Auteur ; Thierry Duquesnoy , Auteur ; Romain Fagès , Auteur ; Bruno Garayt , Auteur ; Elise-Rachel Mathis , Auteur ; Thierry Person , Auteur ; Sébastien Saur , Auteur Année de publication : 2018 Projets : RESIF-CORE / Vergne, Jérôme Article en page(s) : pp 3721 - 3737 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale [Termes IGN] Alpes occidentales [Termes IGN] coordonnées GPS [Termes IGN] séisme [Termes IGN] série temporelle Résumé : (auteur) The availability of GPS survey data spanning 22 years, along with several independent velocity solutions including up to 16 years of permanent GPS data, presents a unique opportunity to search for persistent (and thus reliable) deformation patterns in the Western Alps, which in turn allow a reinterpretation of the active tectonics of this region. While GPS velocities are still too uncertain to be interpreted on an individual basis, the analysis of range-perpendicular GPS velocity profiles clearly highlights zones of extension in the center of the belt (15.3 to 3.1 nanostrain/year from north to south), with shortening in the forelands. The contrasting geodetic deformation pattern is coherent with earthquake focal mechanisms and related strain/stress patterns over the entire Western Alps. The GPS results finally provide a reliable and robust quantification of the regional strain rates. The observed vertical motions of 2.0 to 0.5 mm/year of uplift from north to south in the core of the Western Alps is interpreted to result from buoyancy forces related to postglacial rebound, erosional unloading, and/or viscosity anomalies in the crustal and lithospheric root. Spatial decorrelation between vertical and horizontal (seismicity related) deformation calls for a combination of processes to explain the complex present-day dynamics of the Western Alps. Numéro de notice : A2018-681 Affiliation des auteurs : IGN+Ext (2012-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1029/2018TC005054 Date de publication en ligne : 03/09/2018 En ligne : https://doi.org/10.1029/2018TC005054 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98132 [article]