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Mascle, J; Guiraud, M; Benkhelil, J; Basile, C; Bouillin, Jp; Mascle, G; Cousin, M; Durand, M; Dejax, J; Moullade, M. |
During the Equanaute survey (June 1992), fourteen submersible dives were performed between 4950 and 2250 m water depths across the southern slope of the Cote d'Ivoire-Ghana Marginal Ridge (CIGMR), in the eastern Equatorial Atlantic. The CIGMR, a high-standing topographic marginal ridge along the Cote d'Ivoire-Ghana transform margin, is believed to result from a complex structural evolution due to the specific wrench-related rifting between Western Equatorial Africa and Northeastern Brazil, in Early Cretaceous times. In this paper we report and discuss geological observations made during dives, and sample analyses to resolve the lithology, paleoenvironmental conditions, age and origin of the CIGMR. The data help in better characterizing the different... |
Tipo: Text |
Palavras-chave: Marge transformante; Géologie; Côte d’lvoire-Ghana; Atlantique Equatorial; Transform margin; Geology; Côte d’Ivoire-Ghana; Equatorial Atlantic. |
Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00326/43694/43118.pdf |
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Le Pichon, X; Huchon, P; Angelier, J; Lyberis, N; Boulin, J; Bureau, D; Cadet, J P; Blanchet, R; Montadert, L; Dercourt, J; Glacon, G; Got, H; Karig, D; Mascle, J; Ricou, Le; Thiebault, F. |
Active deformation of the sea-floor of the Hellenic trench has been observed using the Cyana SP-3000 submersible. The strain pattern observed on a scale of a few kilometers is similar to the one deduced from an analysis of Seabeam morphological maps on a scale of tens of kilometers. The overall strain pattern is compatible with subduction of the Mediterranean sea-floor toward the northeast. It is characterized by underthrusting in the Western Ionian branch and left-lateral strike-slip faulting in the Eastern Strabo branch. |
Tipo: Text |
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Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/00246/35697/34205.pdf |
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Dupre, Stephanie; Woodside, J; Foucher, Jean-paul; De Lange, G; Mascle, J; Boetius, A; Mastalerz, V; Stadnitskaia, A; Ondreas, Helene; Huguen, C; Harmegnies, Francois; Gontharet, Swanne; Loncke, L; Deville, E; Niemann, H; Omoregie, E; Olu, Karine; Fiala Medioni, A; Dahlmann, A; Caprais, Jean-claude; Prinzhofer, A; Sibuet, Myriam; Pierre, C; Damste, J. |
Four mud volcanoes of several kilometres diameter named Amon, Osiris, Isis, and North Alex and located above gas chimneys on the Central Nile Deep Sea Fan, were investigated for the first time with the submersible Nautile. One of the objectives was to characterize the seafloor morphology and the seepage activity across the mud volcanoes. The seepage activity was dominated by emissions of methane and heavier hydrocarbons associated with a major thermal contribution. The most active parts of the mud volcanoes were highly gas-saturated (methane concentrations in the water and in the sediments, respectively, of several hundreds of nmol/L and several mmol/L of wet sediment) and associated with significantly high thermal gradients (at 10 m below the seafloor,... |
Tipo: Text |
Palavras-chave: Seafloor morphology; Methane; Authigenic carbonate precipitation; Gas chimneys; Mud breccia; Mud volcanoes; Fluid seepage; Nile fan. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-4455.pdf |
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