Matias Tramontini, Universidad Nacional de La Plata, Facultad de Ciencias Astronomicas y Geofisicas, La Plata, Argentina, Marina Rosas-Carbajal, Université de Paris, Institut de Physique du Globe de Paris, Paris, France, Christophe Nussbaum, CSIRO Earth Science and Resource Engineering Perth, Perth, WA, Australia, Dominique Gibert, University of Rennes, OSUR/Geosciences Rennes UMR6118 CNRS, Rennes Cedex, France and Jacques Marteau, IPNL, Lyon, France