1. GEOMAR, Helmholtz Centre for Ocean Research Kiel; Kiel Germany
2. Now at Department of Earth and Environmental Sciences, Section for Mineralogy, Petrology, and Geochemistry; LMU, Ludwig-Maximilians-Universität München; Munich Germany
3. CEOAS, College of Earth, Oceanic, and Atmospheric Sciences; Oregon State University; Corvallis Oregon USA
4. Geological Survey of Norway; Trondheim Norway
5. CAGE-Centre for Arctic Gas Hydrate, Environment and Climate, Department of Geology; University of Tromsø; Tromsø Norway