|
|
|
|
|
Cathalot, Cecile; Rabouille, Christophe; Tisnerat-laborde, N.; Toussaint, Flora; Kerherve, P.; Buscail, R.; Loftis, K.; Sun, M. -y.; Tronczynski, Jacek; Azoury, S.; Lansard, Bruno; Treignier, Claire; Pastor, L.; Tesi, T.. |
A significant fraction of the global carbon flux to the ocean occurs in River-dominated Ocean Margins (RiOMar) although large uncertainties remain in the cycle of organic matter (OM) in these systems. In particular, the OM sources and residence time have not been well clarified. Surface (0-1 cm) and sub-surface (3-4 cm) sediments and water column particles (bottom and intermediate depth) from the Rhone River delta system were collected in June 2005 and in April 2007 for a multi-proxy study. Lignin phenols, black carbon (BC), proto-kerogen/BC mixture, polycyclic aromatic hydrocarbons (PAHs), carbon stable isotope (delta C-13(OC)), and radiocarbon measurements (delta C-14(OC)) were carried out to characterize the source of sedimentary organic material and to... |
Tipo: Text |
|
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00157/26784/25673.pdf |
| |
|
|
Garcia Garcia, Ana; Orange, D; Lorenson, T; Radakovitch, O; Tesi, T.; Miserocchi, S; Berne, Serge; Friend, P.l.; Nittrouer, C; Normand, Alain. |
Sediment cores acquired in 2004 off the Rhone prodelta show consistent anomalous methane concentrations of up to 87,440 ppm. Methane compositional and isotopic data support a biogenic origin, although there are a few sites that show strongly depleted delta C-13 values (-53%o PDB) suggesting a mixed source for the gas (biogenic and thermogenic). Anomalous methane concentrations (samples with more than 90 ppm) are discussed and integrated with organic carbon data, sedimentary rates and ADCP profiles. Highest gas concentrations were found directly off the river mouth (20-40 m water depth) and where the IFREMER models point to the thickest accumulation (> 2 m) in response to the Rhone flood event. In areas unaffected by the high flux of organic matter and... |
Tipo: Text |
Palavras-chave: Gulf of Lions; Rhone prodelta; Flood deposits; Biogenic methane; Shallow gas. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2396.pdf |
| |
|
|
|