1. 1Geological Survey of Denmark and Greenland, 1350 Copenhagen, Denmark
2. 2Global Maritime Geosciences, London EC2A 2DW, UK
3. 3Leibniz Institute for Baltic Sea Research, Warnemünde, D-18119 Rostock, Germany
4. 4Institute of Marine and Environmental Sciences, University of Szczecin, 70-500 Szczecin, Poland
5. 5Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA
6. 6Department of Earth System Science, University of California, Irvine, California 92697, USA
7. 7Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA