Source model of deformation at Lazufre volcanic center, central Andes, constrained by InSAR time series

Recent interferometric synthetic aperture radar (InSAR) observations of the Lazufre region, central Andes, show large-scale uplift at a rate of about 3 cm/yr, beginning between 1998 and 2002. The initiation of this activity during the ERS satellite mission and its proximity to active volcanoes have made Lazufre the focus of several studies aimed at understanding its source geometry, its relation to nearby volcanoes, and whether or not the source area is expanding. There now exists a longer time series from multiple ERS/ENVISAT satellite tracks that allows a more comprehensive examination of the source geometry and its temporal and spatial variation, if any. We processed 15 years of InSAR data from three separate tracks; modeling the different look geometries provided greater resolution of source depth and geometry. We conclude that the source is a shallowly dipping sill at a depth of about 8 km, with no evidence of lateral expansion.