1. Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, F-38000 Grenoble, France
2. Stanford University, Stanford, CA 94305, USA
3. GFZ German Research Institute for Geosciences & Institute for Earth and Environmental Sciences, University of Potsdam, D-14473 Potsdam, Germany