1. 1Institute of Earth Sciences, University of Lausanne, 1015 Lausanne, Switzerland
2. 2Earth and Planetary Sciences Department, University of New Mexico, Albuquerque, New Mexico 87131, USA
3. 3Laboratoire de Pétrologie Sédimentaire, Département de Géologie, Université de Liège, 4000 Liège, Belgium
4. 4Department of Atmospheric, Oceanic, and Earth Sciences, George Mason University, Fairfax, Virginia 22030, USA
5. 5Natural History Museum, University of Oslo, 0562 Oslo, Norway