Changes in seabed morphology, mud temperature and free gas venting at the Håkon Mosby mud volcano, offshore northern Norway, over the time period 2003-2006
|Author(s)||Foucher Jean-Paul1, Dupre Stephanie2, Scalabrin Carla1, Feseker Tomas3, Harmegnies Francois1, Nouze Herve1|
|Affiliation(s)||1 : IFREMER, Ctr Brest, F-29280 Plouzane, France.
2 : Univ Paris 06, LOCEAN, Paris, France.
3 : Univ Kiel, Leibniz Inst Marine Sci, IFM GEOMAR, Kiel, Germany.
4 : Univ Kiel, Leibniz Inst Marine Sci, IFM GEOMAR, Kiel, Germany.
|Meeting||9th International Conference on Gas in Marine Sediments, Bremen, GERMANY, SEP 15-19, 2008|
|Source||Geo-marine Letters (0276-0460) (Springer), 2010-06 , Vol. 30 , N. 3-4 , P. 157-167|
|WOS© Times Cited||30|
|Keyword(s)||sw barents sea, cold seep ecosystems, fluid flow, methane, sediment, onshore, fluxes, margin, water|
|Abstract||The Håkon Mosby mud volcano is a 1.5-km-diameter geological structure located on the Southwest Barents Sea slope at a water depth of 1,270 m. High-definition seabed mapping of the mud volcano has been carried out in 2003 and 2006. A comparative analysis of the bathymetry and backscatter maps produced from the two surveys shows subtle morphological changes over the entire crater of the mud volcano, interpreted to be the consequence of mud eruption events. Mud temperature measurements point to a persistently warm mud at shallow depth in the crater. This is explained by upward fluid advection, rather than conductive cooling of mud flows. The small-scale spatial variability in the temperature distribution may be related to mud outflows or changes in the fluid flow regime. Furthermore, the locations of free gas venting observed in 2006 were found to differ from those of 2003. Our observations of overall similar topographic profiles across the mud volcano in 2003 and 2006 suggest that eruption events would have been modest. Nevertheless, the data bring evidence of significant change in activity even over short time intervals of only 3 years. This may be a characteristic shared by other submarine mud volcanoes, notably those considered to be in a quiescent stage.|