1. Geological Survey of Denmark and Greenland (GEUS) C.F. Møllers Allé 8 DK‐8000 Aarhus C Denmark
2. Department of Geoscience Aarhus University Høegh‐Guldbergs Gade 2 DK‐8000 Aarhus C Denmark
3. Leibniz Institute for Baltic Sea Research Seestraße 15 D‐18119 Rostock‐Warnemünde Germany
4. Institute of Geology and Mineralogy University of Cologne Zülpicher Str. 49a 50674 Cologne Germany