1. School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom. E-mail: l.parisi@uea.ac.uk
2. Department of Earth Sciences, University College of London, London, United Kingdom
3. ICIST, DECivil, Instituto Superior Técnico, Universidade de Lisboa, Portugal
4. Laboratoire de Planétologie et Géodynamique de Nantes (UMR 6112), CNRS, Université de Nantes, France