Peuplements benthiques et caractéristiques trophiques du milieu dans la plaine abyssale de Demerara Auteur(s) : Sibuet, Myriam Monniot, C Desbruyeres, Daniel Dinet, A Khripounoff, Alexis Rowe, G Segonzac, Michel Éditeur(s) : Gauthier-Villars Oceanologica Acta (0399-1784) (Gauthier-Villars), 1984 , Vol. 7 , N. 3 , P. 345-358 Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00131/24217/22210.pdf http://archimer.ifremer.fr/doc/00131/24217/ | Partager |
Ecological and genetical survey on two deep-sea holothurians: Benthogone rosea and Benthodytes typica Auteur(s) : Bisol, Paolo Maria Costa, Rodolfo Sibuet, Myriam Éditeur(s) : Inter-research Marine Ecology Progress Series (0171-8630) (Inter-research), 1984 , Vol. 15 , N. 3 , P. 275-281 Droits : Inter-Research Printed in F. R. Germany http://archimer.ifremer.fr/doc/00179/28991/27415.pdf DOI:10.3354/meps015275 http://archimer.ifremer.fr/doc/00179/28991/ | Partager |
Multi-disciplinary investigation of fluid seepage on an unstable margin: The case of the Central Nile deep sea fan Auteur(s) : Bayon, Germain Loncke, L. Dupre, Stephanie Caprais, Jean-claude Ducassou, E. Duperron, Sebastien Etoubleau, Joel Foucher, Jean-paul Éditeur(s) : Elsevier Résumé : We report on a multidisciplinary study of cold seeps explored in the Central Nile deep-sea fan of the Egyptian margin. Our approach combines in situ seafloor observation, geophysics, sedimentological data, measurement of bottom-water methane anomalies, pore-water and sediment geochemistry, and Th-230/U dating of authigenic carbonates. Two areas were investigated, which correspond to different sedimentary provinces. The lower slope, at similar to 2100 m water depth, indicates deformation of sediments by gravitational processes, exhibiting slope-parallel elongated ridges and seafloor depressions. In contrast, the middle slope, at similar to 1650 m water depth, exhibits a series of debris-flow deposits not remobilized by post-depositional gravity processes. Significant differences exist between fluid-escape structures from the two studied areas. At the lower slope, methane anomalies were detected in bottom-waters above the depressions, whereas the adjacent ridges show a frequent coverage of fractured carbonate pavements associated with chemosynthetic vent communities. Carbonate U/Th age dates (similar to 8 kyr BP), pore-water sulphate and solid phase sediment data suggest that seepage activity at those carbonate ridges has decreased over the recent past. In contrast, large (similar to 1 km(2)) carbonate-paved areas were discovered in the middle slope, with U/Th isotope evidence for ongoing carbonate precipitation during the Late Holocene (since similar to 5 kyr BP at least). Our results suggest that fluid venting is closely related to sediment deformation in the Central Nile margin. It is proposed that slope instability leads to focused fluid flow in the lower slope and exposure of 'fossil' carbonate ridges, whereas pervasive diffuse flow prevails at the unfailed middle slope. Marine Geology (0025-3227) (Elsevier), 2009-06 , Vol. 261 , N. 1-4 , P. 92-104 Droits : 2009 Elsevier B.V. All rights reserved. http://archimer.ifremer.fr/doc/2009/publication-6586.pdf DOI:10.1016/j.margeo.2008.10.008 http://archimer.ifremer.fr/doc/00000/6586/ | Partager |
Ophidiaster reyssi, nouvelle espèce d'astéride bathyale de l'océan atlantique Auteur(s) : Sibuet, Myriam Éditeur(s) : Museum National d'Histoire Naturelle Résumé : -A new species was found among the Asteroids collected near the Açores at a depth of 350 m.This species is described and attributed to the genus Ophidiaster according to the presence of 8 series of pore areas. Some characters can be related to the genus Hacelia and Tamaria mainly the massive shape of the triangular arms and the series of subrectangular actinal plates Besides, the valvula-pedicellarian are few and are situated dorsally, further the pore areas contains more than 40 pores each, these characters are specific to Ophidiaster reyssi n. sp. [NOT CONTROLLED OCR] Parmi les Astérides récoltées au large des Açores par 350 m de profondeur, une espèce nouvelle est décrite.La présence de huit rangées d'aires papulaires a contribué à attribuer la nouvelle espèce au genre Ophidiaster, mais il est à remarquer quelques caractères qui la rapprochent des genres Hacelia et Tamaria, notamment la forme massive des bras à section triangulaire, et les séries de plaques actinales subrectangulaires. D'autre part, la présence rare de pédicellaires valvulaires dorsaux et de plus de 40 pores par aire papulaire sont des caractères propres à Ophidiaster reyssi n. sp. [OCR NON CONTRÔLE] Bulletin du Museum National d'Histoire Naturelle (Museum National d'Histoire Naturelle), 1977 , Vol. 3 , N. 494 , P. 1085-1090 Droits : Museum National d'Histoire Naturelle http://archimer.ifremer.fr/doc/1977/publication-5199.pdf http://archimer.ifremer.fr/doc/00000/5199/ | Partager |
Deep-sea environment and biodiversity of the West African Equatorial margin Auteur(s) : Sibuet, Myriam Vangriesheim, Annick Éditeur(s) : Elsevier Résumé : The long-term BIOZAIRE multidisciplinary deep-sea environmental program on the West Equatorial African margin organized in partnership between Ifremer and TOTAL aimed at characterizing the benthic community structure in relation with physical and chemical processes in a region of oil and gas interest. The morphology of the deep Congo submarine channel and the sedimentological structures of the deep-sea fan were established during the geological ZAIANGO project and helped to select study sites ranging from 350 to 4800 m water depth inside or near the channel and away from its influence. Ifremer conducted eight deep-sea cruises on board research vessels between 2000 and 2005. Standardized methods of sampling together with new technologies such as the ROV Victor 6000 and its associated instrumentation were used to investigate this poorly known continental margin. In addition to the study of sedimentary environments more or less influenced by turbidity events, the discovery of one of the largest cold seeps near the Congo channel and deep coral reefs extends our knowledge of the different habitats of this margin. This paper presents the background, objectives and major results of the BIOZAIRE Program. It highlights the work achieved in the 16 papers in this special issue. This synthesis paper describes the knowledge acquired at a regional and local scale of the Equatorial East Atlantic margin, and tackles new interdisciplinary questions to be answered in the various domains of physics, chemistry, taxonomy and ecology to better understand the deep-sea environment in the Gulf of Guinea. Deep Sea Research Part II: Topical Studies in Oceanography (0967-0645) (Elsevier), 2009-11 , Vol. 56 , N. 23 , P. 2156-2168 Droits : 2009 Elsevier Ltd All rights reserved. http://archimer.ifremer.fr/doc/2009/publication-7349.pdf DOI:10.1016/j.dsr2.2009.04.015 http://archimer.ifremer.fr/doc/00000/7349/ | Partager Voir aussi Cold coral Cold seep communities Benthos diversity Turbidity current Congo canyon Gulf of Guinea Télécharger |
Biogeography and Potential Exchanges Among the Atlantic Equatorial Belt Cold-Seep Faunas Auteur(s) : Olu, Karine Cordes, Erik E. Fisher, Charles R. Brooks, James M. Sibuet, Myriam Desbruyeres, Daniel Éditeur(s) : Public Library Science Résumé : Like hydrothermal vents along oceanic ridges, cold seeps are patchy and isolated ecosystems along continental margins, extending from bathyal to abyssal depths. The Atlantic Equatorial Belt (AEB), from the Gulf of Mexico to the Gulf of Guinea, was one focus of the Census of Marine Life ChEss (Chemosynthetic Ecosystems) program to study biogeography of seep and vent fauna. We present a review and analysis of collections from five seep regions along the AEB: the Gulf of Mexico where extensive faunal sampling has been conducted from 400 to 3300m, the Barbados accretionary prism, the Blake ridge diapir, and in the Eastern Atlantic from the Congo and Gabon margins and the recently explored Nigeria margin. Of the 72 taxa identified at the species level, a total of 9 species or species complexes are identified as amphi-Atlantic. Similarity analyses based on both Bray Curtis and Hellinger distances among 9 faunal collections, and principal component analysis based on presence/absence of megafauna species at these sites, suggest that within the AEB seep megafauna community structure is influenced primarily by depth rather than by geographic distance. Depth segregation is observed between 1000 and 2000m, with the middle slope sites either grouped with those deeper than 2000m or with the shallower sites. The highest level of community similarity was found between the seeps of the Florida escarpment and Congo margin. In the western Atlantic, the highest degree of similarity is observed between the shallowest sites of the Barbados prism and of the Louisiana slope. The high number of amphi-atlantic cold-seep species that do not cluster according to biogeographic regions, and the importance of depth in structuring AEB cold-seep communities are the major conclusions of this study. The hydrothermal vent sites along the Mid Atlantic Ridge (MAR) did not appear as "stepping stones" for dispersal of the AEB seep fauna, however, the south MAR and off axis regions should be further explored to more fully test this hypothesis. Plos One (1932-6203) (Public Library Science), 2010-08 , Vol. 5 , N. 8 , P. 1-11 Droits : © 2010 Olu et al. http://archimer.ifremer.fr/doc/00011/12207/8975.pdf DOI:10.1371/journal.pone.0011967 http://archimer.ifremer.fr/doc/00011/12207/ | Partager |
Le genre Hymenaster (Astérides) dans l'océan Atlantique Auteur(s) : Sibuet, Myriam Éditeur(s) : Museum National d'Histoire Naturelle Résumé : Several species of the genus Hymenaster (Asteroidea) collected in the abyssal cruises Biaçores, Biogas and Polygas in the North East Atlantic Ocean make possible a synthesis of available data on the species known from the Atlantic Ocean. Two species H. reticulatus and H. tenuispinus are new to Science. A morphological comparative study is carried out for the 17 species reviewed and is presented in the form of a tabular key. The bathymetrical and geographical distributions are included. [NOT CONTROLLED OCR] La présence de nombreuses espèces du genre Hymenaster dans les collections d'Astérides provenant de prélèvements abyssaux effectués dans le Nord-Est Atlantique (missions Biaçores, Biogas et Polygas) a conduit à une étude synthétique de l'ensemble des espèces connues de l'océan Atlantique. Deux espèces, H. reticulatus et H. tenuispinus, sont nouvelles pour la Science et portent à 17 le nombre d'espèces connues de l'océan Atlantique. Une clef tabulaire résume les caractères distinctifs entre ces espèces dont la répartition biogéographique et bathymétrique est étudiée. [OCR NON CONTRÔLE] Bulletin du Museum National d'Histoire Naturelle (Museum National d'Histoire Naturelle), 1976 , Vol. 368 , N. 256 , P. 305-324 Droits : Museum National d'Histoire Naturelle http://archimer.ifremer.fr/doc/1976/publication-5094.pdf http://archimer.ifremer.fr/doc/00000/5094/ | Partager |
Échinodermes de la mer d'Alboran Auteur(s) : Sibuet, Myriam Éditeur(s) : Museum National d'Histoire Naturelle Résumé : During the " Jean Charcot " cruise Polymed II, 18 species of the 5 classes of Echinodermata have been collected in 15 samples from the bathyal zone of the Alboran sea. Most species are already known from the Mediterranean and the North East Atlantic. Some rare species (Odontaster mediterranea, Ophiactis balli) have been collected, and two others (Neocomatella europaea. Henricia abyssalis) are recorded for the first time in the Mediterranean. Endemic distributions of Ceramaster hystricis and Ophiocten abyssicolum are discussed. The Echinoderms population of the Alboran sea is noteworthy for its Atlantic characteristic, which is besides, dominating in the North part of this area. The atlantic biogeographical relationships of the Echinoderm fauna of the Alboran sea is especially perceptible in the northern part of the basin. [NOT CONTROLLED OCR] Lors de la campagne Polymède II du " Jean Charcot ", 18 espèces appartenant aux cinq classes d'Échinodermes ont été récoltées dans 15 prélèvements effectués dans l'étage bathyal de la mer d'Alboran. La plupart des espèces sont connues à la fois de la Méditerranée et des côtes européennes et africaines de l'Atlantique. On peut signaler la récolte d'espèces considérées comme rares en Méditerranée (Odontaster mediterranea, Ophiactis balli) et d'autres nouvelles pour cette mer (Neocomatella europaea, Henricia abyssalis). L'endémisme de deux espèces Ceramaster hystricis et Ophiocten abyssicolum est rediscuté. La faune échinologique de la mer d'Alboran se caractérise par sa dominance atlantique par ailleurs plus sensible au nord qu'au sud. [OCR NON CONTRÔLE] Bulletin du Museum National d'Histoire Naturelle (Museum National d'Histoire Naturelle), 1974-08 , Vol. 3 , N. 231 , P. 25-34 Droits : Museum National d'Histoire Naturelle http://archimer.ifremer.fr/doc/1974/publication-4975.pdf http://archimer.ifremer.fr/doc/00000/4975/ | Partager |