|
|
|
| Registros recuperados: 67 | |
|
|
| Pattier, France; Loncke, L.; Imbert, Patrice; Gaullier, V.; Basile, C.; Maillard, Alexandre; Roest, Walter; Patriat, Martin; Vendeville, B. C.; Marsset, Tania; Bayon, Germain; Cathalot, Cecile; Caprais, Jean-claude; Bermell, Sylvain; Sotin, Christine; Hebert, Bertil; Mercier De Lepinay, Marion; Lebrun, J. F.; Marcaillou, B.; Heuret, A.; Droz, Laurence; Graindorge, David; Poetisi, E.; Berrenstein, H.. |
| The Demerara plateau, located offshore French Guiana and Suriname, is part of a passive transform continental margin particularly prone to develop slope instabilities, probably in relation to the presence of a free distal border along its steep continental slope. Slope failure occurred at different periods (Cretaceous to Neogene) and shows an overall retrogressive evolution through time. Upslope these failure headscarp, an enigmatic regional MioPliocene unconformity has been discovered through the interpretation of new academic and industrial datasets. The aim of this work is to describe and understand the origin of this surface. Our analysis shows that this unconformity is made of a series of valleys that cross-cut sedimentary strata. Each one of these... |
| Tipo: Text |
Palavras-chave: Unconformity; Hydrate pockmark; Slide; Contourite; Valley; Canyon; Demerara plateau. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00271/38193/36735.pdf |
| |
|
| |
|
|
| Vigneron, Adrien; Cruaud, Perrine; Pignet, Patricia; Caprais, Jean-claude; Gayet, Nicolas; Cambon-bonavita, Marie-anne; Godfroy, Anne; Toffin, Laurent. |
| The Sonora Margin cold seeps present on the seafloor a patchiness pattern of white microbial mats surrounded by polychaete and gastropod beds. These surface assemblages are fuelled by abundant organic inputs sedimenting from the water column and upward-flowing seep fluids. Elevated microbial density was observed in the underlying sediments. A previous study on the same samples identified anaerobic oxidation of methane (AOM) as the potential dominant archaeal process in these Sonora Margin sediments, probably catalysed by three clades of archaeal anaerobic methanotrophs (ANME-1, ANME-2 and ANME-3) associated with bacterial syntrophs. In this study, molecular surveys and microscopic observations investigating the diversity of Bacteria involved in AOM... |
| Tipo: Text |
|
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00168/27921/27279.pdf |
| |
|
|
| Martin, Jean-louis; Marchand, Michel; Le Guellec, Anne-marie; Caprais, Jean-claude. |
| Analyses of pesticides, polychlorobiphenyls (PCB's) and hydrocarbons have been carried out in sediments and water samples from the bays of Jakarta, Banten and Cilacap. Heavy metals (Hg, Cu, Mn, Zn, Fe, Pb, Cd, Ni, Co and Cr) have been analysed in sediment samples fram the same areas. - Organic pollutants : The results show that for pesticides, PCB and hydrocarbons, in water and in sediments, there is no significant pollution for the bays of Banten, Cilacap and Jakarta. The bay of Banten, where most of the concentrations are under the detection limits, that is ta say 2 ug/kg for the sediment and 2 ng/1 for the sea water, can be considered as a reference area. For total hydrocarbons and DDT, the bays of Cilacap and Jakarta show concentrations which can be... |
| Tipo: Text |
|
| Ano: 1983 |
URL: http://archimer.ifremer.fr/doc/00094/20546/18217.pdf |
| |
|
| |
|
|
| Bayon, Germain; Birot, Dominique; Ruffine, Livio; Caprais, Jean-claude; Ponzevera, Emmanuel; Bollinger, C.; Donval, Jean-pierre; Charlou, Jean-luc; Voisset, Michel; Grimaud, S.. |
| For many trace elements, continental margins are the location of intense exchange processes between sediment and seawater, which control their distribution in the water column, but have yet to be fully understood. In this study, we have investigated the impact of fluid seepage at cold seeps on the marine cycle of neodymium. We determined dissolved and total dissolvable (TD) concentrations for REE and well-established tracers of fluid seepage (CH4, TDFe, TDMn), and Nd isotopic compositions in seawater samples collected above cold seeps and a reference site (i.e. away from any fluid venting area) from the Niger Delta margin. We also analyzed cold seep authigenic phases and various core-top sediment fractions (pore water, detrital component, easily leachable... |
| Tipo: Text |
Palavras-chave: Rare earth elements; Neodymium isotopes; Seawater; Cold seeps; Fe-Mn oxyhydroxides; Benthic fluxes. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00066/17754/15571.pdf |
| |
|
|
| Croguennec, Claire; Ruffine, Livio; Dennielou, Bernard; Baudin, Francois; Caprais, Jean-claude; Guyader, Vivien; Bayon, Germain; Brandily, Christophe; Le Bruchec, Julie; Bollinger, Claire; Germain, Yoan; Droz, Laurence; Babonneau, Nathalie; Rabouille, Christophe. |
| On continental margins, sulfate reduction occurs within the sedimentary column. It is coupled with the degradation of organic matter and the anaerobic oxidation of methane. These processes may be significantly disturbed by sedimentary events, leading to transient state profiles for the involved chemical species. Yet, little is known about the impact of turbidity currents and mass wasting on the migration of chemical species and the redox reactions in which they are involved. Due to its connection to the River, the Congo deep-sea fan continuously receives huge amount of organic matter-rich sediments primarily transported by turbidity currents, which impact on the development of the associated ecosystems (Rabouille et al., 2016). Thus, it is well suited to... |
| Tipo: Text |
|
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00363/47410/47403.pdf |
| |
| Registros recuperados: 67 | |
|
|
|
