Consulta: subjectFacets:"Sedimentation rate"
Registros recuperados: 5
Data/hora: 01/06/2024 14:09:06

The Congolobe project, a multidisciplinary study of Congo deep-sea fan lobe complex: Overview of methods, strategies, observations and sampling
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Rabouille, C.; Olu, Karine; Baudin, F.; Khripounoff, Alexis; Dennielou, Bernard; Arnaud-haond, Sophie; Babonneau, Nathalie; Bayle, Christophe; Beckler, J.; Bessette, Sandrine; Bombled, B.; Bourgeois, S.; Brandily, Christophe; Caprais, Jean-claude; Cathalot, Cecile; Charlier, K.; Corvaisier, R.; Croguennec, Chantal; Cruaud, Perrine; Decker, Carole; Droz, L.; Gayet, Nicolas; Godfroy, Anne; Hourdez, S.; Le Bruchec, J.; Saout, Johan; Le Saout, Marie-helene; Lesongeur, Francoise; Martinez, P.; Mejanelle, L.; Michalopoulos, P.; Mouchel, Olivier; Noel, Philippe; Pastor, Lucie; Picot, M.; Pignet, Patricia; Pozzato, L.; Pruski, A. M.; Rabiller, Manuella; Raimonet, M.; Ragueneau, O.; Reyss, J. L.; Rodier, Philippe; Ruesch, Blandine; Ruffine, Livio; Savignac, F.; Senyarich, C.; Schnyder, J.; Sen, Arunima; Stetten, E.; Sun, Ming Yi; Taillefert, M.; Teixeira, S.; Tisnerat-laborde, N.; Toffin, Laurent; Tourolle, Julie; Toussaint, F.; Vetion, G.; Jouanneau, J. M.; Bez, M.
The presently active region of the Congo deep-sea fan (around 330 000 km2), called the terminal lobes or lobe complex, covers an area of 2500 km2 at 4700–5100 m water depth and 750–800 km offshore. It is a unique sedimentary area in the world ocean fed by a submarine canyon and a channel-levee system which presently deliver large amounts of organic carbon originating from the Congo River by turbidity currents. This particularity is due to the deep incision of the shelf by the Congo canyon, up to 30 km into the estuary, which funnels the Congo River sediments into the deep-sea. The connection between the river and the canyon is unique for major world rivers.  In 2011, two cruises (WACS leg 2 and Congolobe) were conducted to simultaneously investigate the...
Tipo: Text
Palavras-chave: Chemosynthetic habitats; Congo deep-sea fan; Fine sediment; Sedimentation rate; Seafloor morphology; Turbidite; Vesicomyidae.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00335/44580/44298.pdf

Nature and rates of fine-sedimentation on a mid-shelf: "La Grande Vasiere" (Bay of Biscay, France)
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Dubrulle, C; Jouanneau, J; Lesueur, P; Bourillet, Jean-francois; Weber, O.
The study area, "La Grande Vasiere" (LGV), stretches out on the French Atlantic continental shelf (at ca. 100 m water depth), along 250 km from the Glenan Islands at the north to the southwest of Rochebonne at the south. Box-cores were sampled in this mid-shelf area during four cruises in June 1995, and in April, June and September 2002. They were investigated using sedimentologicat approaches (X-radiographs and grain-size analyses) and radionuclide studies (Pb-210 geochronology and excess Th-234). The main results are: (1) the surficial sediments are generally organized into a decimetrescale fining up sequence which can be the result of extreme storms; (2) an upper mixing layer of 7-20cm reflects an important biological benthic activity and/or the impact...
Tipo: Text
Palavras-chave: Bay of Biscay; Continental shelf; Sedimentation rate; Radionuclides; Fine sediment fraction; Mud.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-3539.pdf

Magnetic mineral diagenesis in the river-dominated inner shelf of the East China Sea, China
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Ge, Can; Zhang, Weiguo; Dong, Chenyin; Dong, Yan; Bai, Xuexin; Liu, Jinyan; Thi Thu Hien, Nguyen; Feng, Huan; Yu, Lizhong.
The inner shelf of the East China Sea is a river-dominated margin characterized by fine-grained mud deposits and a rapid sedimentation rate. Three short sediment cores (similar to 2.7m in length) were examined to characterize spatial variations in magnetic mineral diagenesis. The sediment cores were analyzed for sedimentation rates, magnetic properties, particle size distribution, organic carbon, and total sulfur content. The two more proximal cores with higher sedimentation rates (similar to 2.2cm/yr and similar to 0.96cm/yr) do not exhibit obvious effects of reductive dissolution of magnetite with increasing depth, which is consistent with their lower total sulfur content. The offshore core, A12-4, which has a lower sedimentation rate, contains clear...
Tipo: Text
Palavras-chave: Magnetic properties; Diagenesis; Organic matter reactivity; Sedimentation rate; River-dominated margin; East China Sea.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00351/46256/46079.pdf

Biotracers and geotracers of depositional events in NW Mediterranean margin over the past two centuries
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Giresse, P; Buscail, R; Charriere, B; Abassi, A; Masque, P; Sanchez-cabeza, Ja.
A detailed sedimentological and geochemical investigation was performed on slope sediments collected from the Gulf of Lions and Catalonian margins and from the northern Balearic margin. The study was based on cores, about 50 cm long. Various physiographic sites (canyons, open slopes) were selected according to the available sediment accumulation rates obtained with the Pb-210 geochronological method. At a short time scale, various parts of the slope were characterized by muddy hemipelagic sediment. Sedimentological data suggested that deposition was continuous. Total organic carbon and its hydrolysable fraction decreased downcore. Significant increase of C/N ratio downcore resulted from an early diagenetic process in response to the burial effect. However...
Tipo: Text
Palavras-chave: Méditerranée nord-occidentale; Vitesse de sédimentation; Processus gravitaires; Carbone organique; 210Pb; North-western Mediterranean; Sedimentation rate; Gravity-induced process; Organic carbon; Pb-210.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/00322/43335/42892.pdf

Morphological changes and sedimentary processes induced by the December 2003 flood event at the present mouth of the Grand Rhone River (southern France)
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Maillet, Grégoire M.; Vella, Claude; Berne, Serge; Friend, Patrick L.; Amos, Carl L.; Fleury, Thomas J.; Normand, Alain.
The study, which is based on repetitive bathymetric surveys, assesses changes and effects of one of the most important floods recorded in the Rhone Delta area: bottom morphology and sediment distribution in the Rhone outlet after the December 2003 flood are discussed by comparison between Digital Terrain maps (DTMs) of November 2003 and January 2004. The post-flood morphology shows that the whole of the system is active, mainly in the east. The channel of the Rhbne has been hollowed out on the left bank by more than 5 m, the eastern coast of the mouth has retreated 400 m, the mouth-bar has prograded 200 m and the slope of the delta front has increased by 0.19. The overlay of pre- and post-flood DTMs makes it possible to estimate the total volume deposited...
Tipo: Text
Palavras-chave: Bathymetric maps; Sedimentation rate; Flood processes; Prodelta; Delta front; Mouth bar.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-2304.pdf