Walpersdorf A., Sue C., Baize S., Cotte N., Bascou P., Beauval Céline, Collard P., Daniel G., Dyer H., Grasso J. R., Hautecoeur O., Helmstetter A., Hok S., Langlais M., Menard G., Mousavi Z., Ponton F., Rizza M., Rolland L., Souami D., Thirard L., Vaudey P., Voisin Christophe, Martinod J. (2015). Coherence between geodetic and seismic deformation in a context of slow tectonic activity (SW Alps, France). Journal of Geodynamics, 85, p. 58-65. ISSN 0264-3707.
Titre du document
Coherence between geodetic and seismic deformation in a context of slow tectonic activity (SW Alps, France)
Année de publication
2015
Auteurs
Walpersdorf A., Sue C., Baize S., Cotte N., Bascou P., Beauval Céline, Collard P., Daniel G., Dyer H., Grasso J. R., Hautecoeur O., Helmstetter A., Hok S., Langlais M., Menard G., Mousavi Z., Ponton F., Rizza M., Rolland L., Souami D., Thirard L., Vaudey P., Voisin Christophe, Martinod J.
Source
Journal of Geodynamics, 2015,
85, p. 58-65 ISSN 0264-3707
A dense, local network of 30 geodetic markers covering a 50 x 60 km(2) area in the southwestern European Alps (Briancon region) has been temporarily surveyed in 1996, 2006 and 2011 by GPS. The aim is to measure the current deformation in this seismically active area. The study zone is characterized by a majority of extensional and dextral focal mechanisms, along north-south to N160 oriented faults. The combined analysis of the three measurement campaigns over 15 years and up to 16 years of permanent GPS data from the French RENAG network now enables to assess horizontal velocities below 1 mm/year within the local network. The long observation interval and the redundancy of the dense campaign network measurement help to constrain a significant local deformation pattern in the Briancon region, yielding an average E-W extension of 16 +/- 11 nanostrain/year. We compare the geodetic deformation field to the seismic deformation rate cumulated over 37 years, and obtain good coherencies both in amplitude and direction. Moreover, the horizontal deformation localized in the Briancon region represents a major part of the Adriatic-European relative plate motion. However, the average uplift of the network in an extensional setting needs the presence of buoyancy forces in addition to plate tectonics.
Plan de classement
Géophysique interne [066]
Description Géographique
FRANCE ; ALPES
Localisation
Fonds IRD [F B010064044]
Identifiant IRD
fdi:010064044
