Impact of dense shelf water cascading on the transfer of organic matter to the deep western Mediterranean basin

A. Sanchez-Vidal (1) , C. Pasqual , Philippe Kerhervé (2) , A. Calafat (3) , S. Heussner (4) , A. Palanques (5) , X. Durrieu de Madron (6) , M. Canals (7) , P. Puig (5)

1 GRC Geociencies Marines
2 CEFREM - Centre de Formation et de Recherche sur les Environnements Méditérranéens
3 Departament de Dinàmica de la Terra i de l’Oceà [Barcelona]
4 CEFREM - Centre de formation et de recherche en environnement marin
5 ICM - Institute of Marine Sciences / Institut de Ciències del Mar [Barcelona]
6 CEFREM - Centre de Formation et de Recherche sur les Environnements Méditérranéens
7 GRC Geosciencies Marines

During winter 2005–2006, particle fluxes and near‐bottom currents were measured in and around the Lacaze‐Duthiers and Cap de Creus submarine canyons (western Gulf of Lion). Current anomalies show the occurrence of a major dense shelf water cascading event down to the slope, the latest recorded up to date in the area. Concomitant increased total mass fluxes highlight the ability of cascading waters to transport large amounts of coarse sediment and organic matter, which is predominantly of terrestrial origin. In addition, results reveal that the current regime and associated grain size sorting is the responsible for a geochemical gradient of settling organic particles along the slope.

Domains: Environment and Society; Global Changes; Continental interfaces, environment; Ocean, Atmosphere

A. Sanchez-Vidal, C. Pasqual, Philippe Kerhervé, A. Calafat, S. Heussner, et al.. Impact of dense shelf water cascading on the transfer of organic matter to the deep western Mediterranean basin. Geophysical Research Letters, 2008, 35 (5), ⟨10.1029/2007GL032825⟩. ⟨hal-04743416⟩