1. Institute of Geosciences, Johannes Gutenberg University, 55122 Mainz, Germany.
2. London Geochemistry and Isotope Centre (LOGIC), Institute of Earth and Planetary Sciences, University College London and Birkbeck, University of London, Gower Place, London WC1E 6BS, UK.
3. Centre for Earth Evolution and Dynamics (CEED), University of Oslo, Pb. 1028 Blindern, 0315 Oslo, Norway.
4. Department of Earth Sciences, University of Southern California, 3651 Trousdale Parkway—ZHS 117, Los Angeles, CA 90089, USA.
5. Centre for Permafrost, University of Copenhagen, Copenhagen, Denmark.
6. National Oceanography Centre Southampton, University of Southampton Waterfront Campus, European Way, Southampton SO14 3ZH, UK.
7. School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol BS8 1RJ, UK.