1. The Njord Centre, Department of Geoscience, University of Oslo, 1048 Blindern, Norway
2. School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, PL4 8AA Plymouth, UK
3. Department of Earth Sciences, ETH Zurich, 8092 Zurich, Switzerland
4. Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
5. Department of Geosciences, University of Padova, Via Gradenigo 6, 35131 Padua, Italy