Consulta: subjectFacets:"Regab"
Registros recuperados: 3
Data/hora: 09/06/2024 06:00:20

Microbial utilization of rare earth elements at cold seeps related to aerobic methane oxidation
Provedor de dados: 5
Autores: Bayon, Germain; Lemaitre, Nolwenn; Barrat, Jean-alix; Wang, Xudong; Feng, Dong; Duperron, Sebastien.
A major breakthrough in the field of rare earth element (REE) geochemistry has been the recent discovery of their utility to microbial life, as essential metalloenzymes catalyzing the oxidation of methanol to formaldehyde. Lanthanide-dependent bacteria are thought to be ubiquitous in marine and terrestrial environments, but direct field evidence of preferential microbial utilization of REE in natural systems is still lacking. In this study, we report on the REE and trace element composition of the tube of a siboglinid worm collected at a methane seep in the Gulf of Guinea; a tube-dwelling annelid that thrives in deep-sea chemosynthetic ecosystems. High-resolution trace element profiles along the chitin tube indicate marked enrichments of lanthanum (La) and...
Tipo: Text
Palavras-chave: Tubeworms; Siboglinidae; Lanthanide-dependent bacteria; Metalloenzymes; Methylotrophy; Regab; Authigenic carbonates; Archaean.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00643/75496/76352.pdf

Helium transport in sediment pore fluids of the Congo-Angola margin
Provedor de dados: 5
Autores: Chaduteau, Carine; Jean-baptiste, Philippe; Fourre, Elise; Charlou, Jean-luc; Donval, Jean-pierre.
During the ZaiRov2 cruise of the ZaiAngo project (1998-2000) on the passive Congo-Angola margin, several gravity cores were analyzed for helium isotopic composition of sedimentary pore waters in two cold fluid seepage zones: the Astrid slide area and the Regab giant pockmark. Gas concentration and isotopic composition are presented along with thermal data in terms of the origin and circulation of fluids. Helium isotope data lie on a mixing line between bottom seawater and an almost pure radiogenic. Helium and temperature vertical profiles are well described by the classic diffusion-advection equation. On the basis of He profiles, we estimate the advection rate on the rim of the pockmark between 1.2 and 2.3 mm/a. The He flux derived for a pure diffusive...
Tipo: Text
Palavras-chave: Zaire Angola margin; Sediment; Regab; Pore fluids; Pockmark; Helium.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6112.pdf

Distribution and temporal variation of mega-fauna at the Regab pockmark (Northern Congo Fan), based on a comparison of videomosaics and geographic information systems analyses
Provedor de dados: 5
Autores: Marcon, Yann; Sahling, Heiko; Allais, Anne-gaelle; Bohrmann, Gerhard; Olu, Karine.
The Regab pockmark is a large cold seep area located 10 km north of the Congo deep sea channel at about 3160 m water depth. The associated ecosystem hosts abundant fauna, dominated by chemosynthetic species such as the mussel Bathymodiolus aff. boomerang, vestimentiferan tubeworm Escarpia southwardae, and vesicomyid clams Laubiericoncha chuni and Christineconcha regab. The pockmark was visited during the West African Cold Seeps (WACS) cruise with RV Pourquoi Pas? in February 2011, and a 14,000-m2 high-resolution videomosaic was constructed to map the most populated area and to describe the distribution of the dominant megafauna (mussels, tubeworms and clams). The results are compared with previous published works, which also included a videomosaic in the...
Tipo: Text
Palavras-chave: Cold seep; Fauna; Mosaic; Pockmark; Regab; Temporal variation.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00144/25528/23765.pdf