1. Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, New Haven, CT, 06511, USA
2. All Souls College, University of Oxford, Oxford, OX1 4AL, UK
3. Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, UK
4. UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, James Clerk Maxwell Building, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, UK
5. Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge, MA, 02138, USA
6. Geology Department, Amherst College, 11 Barrett Hill Road, Amherst, MA, 01002, USA
7. Peabody Museum of Natural History, Yale University, 170 Whitney Avenue, New Haven, CT, 06511, USA