Gas emissions at the continental margin west off Svalbard during R/V Heinche cruise HE387 ...

• Main Authors: Sahling, Heiko, Römer, Miriam, Pape, Thomas, Bergès, Benoit, dos Santos Ferreira, Christian, Boelmann, Jan, Geprägs, Patrizia, Tomczyk, Michal, Nowald, Nicolas, Dimmler, Werner, Schroedter, Leah, Glockzin, Michael, Bohrmann, Gerhard
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2014
• Subjects: Center for Marine Environmental Sciences MARUM; Svalbard; Ferreira; Forlandet; permafrost
• Online Access: https://dx.doi.org/10.1594/pangaea.834000; https://doi.pangaea.de/10.1594/PANGAEA.834000

We mapped, sampled, and quantified gas emissions at the continental margin west of Svalbard during R/V Heincke cruise He-387 in late summer 2012. Hydroacoustic mapping revealed that gas emissions were not limited to a zone just above 396 m below sea level (m b.s.l.). Flares from this depth gained significant attention in the scientific community in recent years because they may be caused by bottom water-warming induced hydrate dissolution in the course of global warming and/or by recurring seasonal hydrate formation and decay. We found that gas emissions occurred widespread between about 80 and 415 m b.s.l. which indicates that hydrate dissolution might only be one of several triggers for active hydrocarbon seepage in that area. Gas emissions were remarkably intensive at the main ridge of the forlandet moraine complex in 80 to 90 m water depths, and may be related to thawing permafrost. Focused seafloor investigations were performed with the remotely operated vehicle (ROV) "Cherokee". Geochemical analyses of ... : Supplement to: Sahling, Heiko; Römer, Miriam; Pape, Thomas; Bergès, Benoit; dos Santos Ferreira, Christian; Boelmann, Jan; Geprägs, Patrizia; Tomczyk, Michal; Nowald, Nicolas; Dimmler, Werner; Schroedter, Leah; Glockzin, Michael; Bohrmann, Gerhard (2014): Gas emissions at the continental margin west of Svalbard: mapping, sampling, and quantification. Biogeosciences, 11(21), 6029-6046 ...