Consulta: creatorFacets:"Jouanneau, Jm"
Registros recuperados: 6
Data/hora: 02/06/2024 15:40:53

Pb, Zn, Cs, Sc and rare earth elements as tracers of the Loire and Gironde particles on the Biscay shelf (SW France)
Provedor de dados: 5
Autores: Jouanneau, Jm; Weber, O; Grousset, Fe; Thomas, B.
The western Atlantic continental margin of the Bay of Biscay is characterised by a combined macro-tidal and a high energy environment. These conditions are responsible for the essentially sandy sedimentary cover along with well-defined fine deposit zones observed on the shelf. The main continental sources are the Loire, Gironde and Adour Rivers. It is estimated that 2.4 to 2.5 million tons of fine sediments are supplied annually to the ocean from these rivers of the French Atlantic coast. The Gironde and the Loire contribute with 84 % and the Gironde with 60 % of this amount. Previous studies of the distribution of the clay mineral assemblages and of oligo-elements have distinguished two provinces (north and south Biscay areas) according to these riverine...
Tipo: Text
Palavras-chave: Sédiment fin; Source; Métaux traces; Terre rare; Golfe de Gascogne; Fine-grained sediment; Origin; Heavy metal; Rare earth element; Bay of Biscay.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00326/43682/43192.pdf

Some evidences of northward fine sediment transport in the northern Portuguese continental shelf
Provedor de dados: 5
Autores: Drago, T; Oliveira, A; Magalhaes, F; Cascalho, J; Jouanneau, Jm; Vitorino, Joao.
On the basis of sedimentological and oceanographical data, a transport scheme for fine-grained material is proposed in order to explain the location of a muddy deposit present in the northern Portuguese continental shelf, north-west off the Douro River mouth. This mid-shelf deposit is recent, active and its main source is apparently the Douro River. The sediment supply can be related with the oceanographic conditions in winter regime, characterised by a poleward along shelf current with a bottom westward component, as a consequence of a south-west wind. The resulting fine sediment transport, essentially made in the bottom nepheloid layer is believed to have a north-west direction.
Tipo: Text
Palavras-chave: Plateau continental portugais; Sédiment fin; Biotite; Transport de sédiments; Hydrologie hivernale; Portuguese shelf; Fine sediments; Biotite; Sediment transport; Winter regime.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00326/43681/43193.pdf

Etude isotopique (Sr-Nd) de l'origine des depots fins holocenes du littoral atlantique (S-O France)
Provedor de dados: 5
Autores: Parra, M; Trouky, H; Jouanneau, Jm; Grousset, F; Latouche, C; Castaing, P.
The fine-grained sediments of the West Gironde mud patch derive mainly from materials supplied via the Gironde estuary. Between 1500 and 1200/1300 years BP and 300/400 years BP and the present day, the Sr isotopic and chemical compositions of the estuarine silty clay inputs are the same. In contrast, these compositions were different during the period 1200/1300 to 300/400 years BP These variations probably reflect anthropogenic activities including cultivation and agriculture, in the Garonne and Dordogne drainage basins during the medieval period. Modern silty clay sedimentation in the mud flats of the Marennes-Oleron basin and Perthuis Breton is characterised by the occurrence of important quantities (between 40 and 90 % of the total) of detritus that...
Tipo: Text
Palavras-chave: Isotope Sr-Nd; Origine; Sédiment fin holocène; Vasière littorale atlantique; Sr-Nd isotope; Origin; Holocene fine-grained deposit; Atlantic littoral mudflat.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00325/43648/43244.pdf

Traceurs organiques dans les dépôts de la vasière Ouest-Gironde (Golfe de Gascogne)
Provedor de dados: 5
Autores: Gadel, F; Jouanneau, Jm; Weber, O; Serve, L; Comellas, L.
Mud fields located In the inner part of shelves in front of large estuaries are preferential environments for the investigation of the mechanisms and evolution in time of the supply of such sedimentary bodies. The study of different constituents of the particulate organic matter trapped in the sediments of the West Gironde mud patch contributes to the knowledge of the input origins. This study was carried out with different techniques, including pyrolysis-gas chromatography-mass spectrometry and high performance liquid chromatography, on samples from a core collected in the centre of the mud field. At the bottom of the core, the increase of sugars, amino-sugars and some aromatic hydrocarbons may indicate a more marine character of organic components. The...
Tipo: Text
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00093/20426/18093.pdf

Le comblement de la ria de Gernika (golfe de Gascogne) à l'Holocène terminal
Provedor de dados: 5
Autores: Pascual, A; Weber, O; Rodriguez-lazaro, J; Jouanneau, Jm; Pujos, M.
A study of the recent sedimentation of the ria de Gernika (Bay of Biscay) is undertaken to characterise different steps of its Holocene filling. Sedimentological and micropalaeontological analysis of six cores sampled in the ria, completed with absolute dating (C-14, and based upon Pb-210 exc.), allow us to identify three phases in the filling of the ria that are Limited by two transgressive shifts (3500 and 2500 yr. B.P.) already described in other areas of the Bay of Biscay. In the first phase, lithologies as well as benthic foraminifera and ostracode assemblages are typical of coastal marine palaeo-environment. During the second phase the euryhaline waters progessively occupy the central area of the estuary. Here the presence of allochthonous...
Tipo: Text
Palavras-chave: Microfaune; Sédimentation; Holocène terminal; Ria de Gernika; Microfauna; Sedimentation; Late Holocene; Ria de Gernika.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00326/43684/43237.pdf

L'expérience "double marquage de vase en Gironde". Contribution à la connaissance du devenir d'une pollution métallique en estuaire
Provedor de dados: 5
Autores: Etcheber, H; Jouanneau, Jm; Latouche, C; Azoeuf, P; Caillot, A; Hoslin, R.
Tipo: Text
Ano: 1980
URL: http://archimer.ifremer.fr/doc/00122/23292/21120.pdf