1. Research School of Earth SciencesAustralian National UniversityCanberra Australian Capital Territory Australia
2. Univ Lyon, ENS de Lyon, Univ Claude BernardCNRS, Laboratoire de PhysiqueLyon France
3. Now at LEMTA ‐ Université de Lorraine CNRS ‐ UMR 7563Nancy France
4. Now at Department of Civil and Environmental Engineering, Imperial College LondonSouth Kensington London, UK