Marie Laugie, Aix-en-Provence, France, Yannick Donnadieu, CNRS, CEREGE, Aix-en-Provence Cedex, France, Jean-Baptiste Ladant, University of Michigan, Earth and Environmental Sciences, Ann Arbor, MI, United States and Mattias Green, Bangor University, School of Ocean Sciences, Bangor, LL59, United Kingdom