1. Department of Earth and Planetary Sciences Harvard University Cambridge MA USA
2. Department of Geological Sciences Stanford University Stanford CA USA
3. Department of Earth Sciences University of California Santa Barbara CA USA
4. Now at Thermo Fisher Scientific Waltham MA USA
5. Department of Geology and Geophysics Louisiana State University Baton Rouge LA USA
6. USGS Menlo Park and Stanford University Stanford CA USA
7. Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences Potsdam Germany
8. Department of Geoscience University of Wisconsin Madison WI USA