Consulta: creatorFacets:"Gente, Pascal"
Registros recuperados: 8
Data/hora: 17/06/2024 18:34:29

Building of the Amsterdam-Saint Paul plateau: A 10 Myr history of a ridge-hot spot interaction and variations in the strength of the hot spot source
Provedor de dados: 5
Autores: Maia, Marcia; Pessanha, Ivo; Courreges, Esther; Patriat, Martin; Gente, Pascal; Hemond, Christophe; Janin, Myriam; Johnson, Kevin; Roest, Walter; Royer, Jean-yves; Vatteville, Judith.
The Amsterdam-Saint Paul plateau results from a 10 Myr interaction between the South East Indian Ridge and the Amsterdam-Saint Paul hot spot. During this period of time, the structure of the plateau changed as a consequence of changes in both the ridge-hot spot relative distance and in the strength of the hot spot source. The joint analysis of gravity-derived crust thickness and bathymetry reveals that the plateau started to form at similar to 10 Ma by an increase of the crustal production at the ridge axis, due to the nearby hot spot. This phase, which lasted 3-4 Myr, corresponds to a period of a strong hot spot source, maybe due to a high temperature or material flux, and decreasing ridge-hot spot distance. A second phase, between similar to 6 and...
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00047/15865/13284.pdf

Fossil clams from a serpentinite-hosted sedimented vent field near the active smoker complex Rainbow, MAR, 36 degrees 13 ' N: Insight into the biogeography of vent fauna
Provedor de dados: 5
Autores: Lartaud, Franck; De Rafelis, Marc; Oliver, Graham; Krylova, Elena; Dyment, Jerome; Ildefonse, Benoit; Thibaud, Remy; Gente, Pascal; Hoise, Eva; Meistertzheim, Anne-leila; Fouquet, Yves; Gaill, Francoise; Le Bris, Nadine.
Hydrothermal circulation at ultramafic-hosted sites supports a large variety of high-and low-temperature hydrothermal vents and associated ecosystems. The discovery of abundant fossil vesicomyid and thyasirid shell accumulations at the ridge crest, approximately 2.5 km east of the active Rainbow vent field on the Mid-Atlantic Ridge (MAR, 36 degrees 13'N), increased our knowledge regarding the diversity of vent communities at slow spreading ridges. Bivalve molluscs of the family Vesicomyidae were represented by the genus Phreagena. Here we present the first record of this genus in the Atlantic Ocean. This second vesicomyid species known from the MAR, Phreagena sp., was found to be associated with a Thyasira species that is affiliated with T. southwardae (at...
Tipo: Text
Palavras-chave: Ultramafic-hosted; Mid-Atlantic Ridge; Bivalve shells; Vesicomyidae; Thyasiridae; Carbon and oxygen isotopes.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00012/12301/9093.pdf

Structure and evolution of the eastern Gulf of Aden: insights from magnetic and gravity data (Encens-Sheba MD117 cruise)
Provedor de dados: 5
Autores: D'Acremont, Elia; Leroy, Sylvie; Maia, Marcia; Patriat, Philippe; Beslier, Marie-odile; Bellahsen, Nicolas; Fournier, Marc; Gente, Pascal.
Magnetic and gravity data gathered during the Encens-Sheba cruise (2000 June) in the eastern Gulf of Aden provide insights on the structural evolution of segmentation from rifted margins to incipient seafloor spreading. In this study, we document the conjugate margins asymmetry, confirm the location of the ocean-continent transition (OCT) previously proposed by seismic data, and describe its deep structure and segmentation. In the OCT, gravity models indicate highly thinned crust while magnetic data indicate presence of non-oceanic high-amplitude magnetic anomalies where syn-rift sediments are not observed. Thus, the OCT could be made of ultra-stretched continental crust intruded by magmatic bodies. However, locally in the north, the nature of the OCT...
Tipo: Text
Palavras-chave: Gulf of Aden; Kinematic evolution; Ocean-continent transition; Passive continental margin; Seafloor spreading; Segmentation.
Ano: 2006
URL: https://archimer.ifremer.fr/doc/00234/34561/33314.pdf

Étude morphostructurale comparative de dorsales océaniques à taux d'expansion variés
Provedor de dados: 5
Autores: Gente, Pascal.
Ce mémoire contient les résultats d'une étude comparative menée sur la morphologie et la structure de différentes dorsales océaniques. Ces frontières divergentes de plaques lithosphériques sont le siège d'évènements tectoniques, volcaniques et hydrothermaux. L'analyse d'un grand nombre de données bathymétriques, structurales (sonar latéral) et d'observations sur le fond (a l'aide du submersible SP 3000 Cyana), sur plusieurs secteurs de différentes dorsales à taux d'expansion variés, constitue la base de ce travail.
Tipo: Text
Ano: 1987
URL: http://archimer.ifremer.fr/doc/00034/14517/11837.pdf

Première exploration in situ de la dorsale médio-Atlantique au sud de la zone de fracture Atlantis (29"06'N-43"1l'W)
Provedor de dados: 5
Autores: Auzende, Jean-marie; Tivey, M; Cannat, M; Gente, Pascal; Henriet, Jean-pierre; Juteau, Thierry; Karson, J; Lagabrielle, Yves.
During the Kanaut cruise of the submersible Nautile and its mothership Le-Nadir (15 November-16 December 1992), one dive was devoted to the detailed study of a specific area of the neovolcanic ridge of the MAR around 29-degrees-06'N and 43-degrees-11'W. This study emphasizes the importance of the juxtaposition and the stacking of hundreds of small volcanoes in the construction of a neovolcanic ridge and confirms the general observation made from multibeam and side-scan sonar data. The very large magnetic anomaly associated with these massifs favours an extreme freshness.
Tipo: Text
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00183/29475/27887.pdf

Accrétion océanique et déformation dans la partie méridionale du bassin Nord-Fidjien: résultats préliminaires de la campagne océanographique SEAPSO III du N.O. Jean-Charcot (décembre 1985)
Provedor de dados: 5
Autores: Auzende, Jean-marie; Eissen, Jean-philippe; Caprais, Marie-paule; Gente, Pascal; Gueneley, S; Harmegnies, Francois; Lagabrielle, Yves; Lapouille, A; Lefevre, C; Maillet, P; Maze, Jean-pierre; Ondreas, Helene; Schaaf, A; Singh, R.
Seismic, Seabeam, magnetic and gravimetrie surveys in the southern part of the N-Fiji basin were conducted during the SEAPSO LEG III Cruise. The active spreading axis was recognized between 17°30'S and 21°S. It consists of a continuous N-S Ridge cross-cut by transverse directions oriented N25 and N45. North of 17°30'S, the spreading System is more complex due to the existence of a possible triple junction located around 15° S. The eastern part of the N-Fiji basin, west of Viti Levu is mostly characterized by alternating highs and deeps (&lt;4,000 m). This area must be regarded no more as a spreading center, but as complex boundary suffering transverse tectonics.
Tipo: Text
Ano: 1986
URL: http://archimer.ifremer.fr/doc/00184/29492/27835.pdf

Detailed Analysis of Near Tectonic Features Along the East Pacific Rise at 16 degrees N, Near the Mathematician Hot Spot
Provedor de dados: 5
Autores: Le Saout, M; Thibaud, R.; Gente, Pascal.
Spreading processes at the axes of fast spreading ridges are mainly controlled by magmatic activity, whereas tectonic activity dominates further away from the axis. High-resolution near-bottom bathymetry data, photographs, videos, and human observations from submersible surveys are used to develop a detailed tectonic analysis of the 16 degrees N segment of the East Pacific Rise (EPR). These data are used to evaluate how a highly magmatic segment, close to a hot spot, affects the nucleation and evolution of faulting patterns and impacts the evaluation of tectonic strain within 2km of the spreading axis. Our study shows that (1) the growth of tectonic features differs in response to dike intrusion and tectonic extension, (2) the initiation of brittle...
Tipo: Text
Palavras-chave: Faulting; Dike intrusion; Brittle deformation; Mid-ocean ridge; East Pacific Rise.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00638/74985/75818.pdf

Affleurements des roches profondes de la croûte océanique et du manteau sur le mur sud de la fracture Kane (Atlantique central) : observations par submersible
Provedor de dados: 5
Autores: Auzende, Jean-marie; Cannat, M; Gente, Pascal; Henriet, Jean-pierre; Juteau, Thierry; Karson, J; Lagabrielle, Yves; Mevel, Christophe; Tivey, M.
The aim of the 20 Nautile dives of the recent Kanaut cruise was the study of the Kane Fracture Zone from its intersection with the Mid-Atlantic Ridge up to 80 km to the west. The dives have been conducted along four massifs located along the southern wall of the fracture valley. The flanks of the massifs consist of slightly tilted peridotites, gabbros and basalts, which have been exposed along normal and strike-slip major faults. No dike complex similar to that observed along the ZF Vema was observed The observed sections show pervasive cataclastic deformation and greenschist-facies metamorphic overprint.
Tipo: Text
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00183/29470/27886.pdf