Persistent uplift of the Lazufre volcanic complex (Central Andes): New insights from PCAIM inversion of InSAR time series and GPS data
Por:
Remy D., Froger J.L., Perfettini H., Bonvalot S., Gabalda G., Albino F., Cayol V., Legrand D., De Saint Blanquat M.
Publicada:
1 ene 2014
Resumen:
We reanalyzed the surface displacements observed at the Lazufre volcanic complex in the Southern Andean Central Volcanic Zone using GPS measurements made between 2006 and 2008 and a large InSAR data set. We performed a detailed spatiotemporal analysis of the displacements using a principal component analysis inversion method (PCAIM). The PCAIM reveals a source with no significant changes in shape and dimension and with a remarkably linear strength increase over the whole period of observation (i.e., 2003-2010). Then we used a three-dimensional mixed boundary element method (MBEM) to invert the first component of surface displacement as obtained from PCAIM. We explored a continuum of geometries from a shallow elliptic crack to a deep massive truncated elliptical cone that could represent a sill or a large magma chamber, respectively. The best models indicate a large flat-topped source with a roof area between 40 and 670 km2 and a depth of between 2 and 14 km below ground surface. Lastly, on the basis of the limited data available for the thermomechanical structure of the crust in the Southern Andean Central Volcanic Zone, we consider some possible scenarios to explain the spatial and temporal pattern of displacements at Lazufre. ©2014. American Geophysical Union.
Filiaciones:
Remy D.:
GET/UMR 5563 (UPS, CNRS, IRD, CNES), Observatoire Midi-Pyrénées, Université P. Sabatier, Toulouse, France
Froger J.L.:
LMV/UMR 6524 (UBP-CNRS-IRD), Observatoire de Physique du Globe de Clermont-Ferrand, Université B. Pascal, Clermont-Ferrand, France
Perfettini H.:
ISTERRE/UMR 5275 (UJF, CNRS, IRD), Observatoire des Sciences de l Univers de Grenoble, Université Joseph Fourier, Grenoble, France
Bonvalot S.:
GET/UMR 5563 (UPS, CNRS, IRD, CNES), Observatoire Midi-Pyrénées, Université P. Sabatier, Toulouse, France
Gabalda G.:
GET/UMR 5563 (UPS, CNRS, IRD, CNES), Observatoire Midi-Pyrénées, Université P. Sabatier, Toulouse, France
Albino F.:
LMV/UMR 6524 (UBP-CNRS-IRD), Observatoire de Physique du Globe de Clermont-Ferrand, Université B. Pascal, Clermont-Ferrand, France
Now at Department of Earth Sciences, Cartography and Remote Sensing Unit, Royal Museum for Central Africa, Tervuren, Belgium
Cayol V.:
LMV/UMR 6524 (UBP-CNRS-IRD), Observatoire de Physique du Globe de Clermont-Ferrand, Université B. Pascal, Clermont-Ferrand, France
Legrand D.:
Departamento de Geofísica, Universidad de Chile, Santiago, Chile
Now at Instituto de Geofisica, Universidad Nacional Autónoma de México, Coyoacan, Mexico
De Saint Blanquat M.:
GET/UMR 5563 (UPS, CNRS, IRD, CNES), Observatoire Midi-Pyrénées, Université P. Sabatier, Toulouse, France
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