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| Registros recuperados: 10 | |
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| Melguen, Marthe; Bolli, Hans M.; Ryan, William B.f.; Foresman, James B.; Hottman, William E.; Kagami, Hideo; Longoria, José F.; Mc Knight, Brian K.; Natland, James; Proto Decpia, Franca; Siesser, William G.. |
| The evolution of the sedimentary facies in the southeast Atlantic Ocean since the Cretaceous is strongly correlated to the structural history of this ocean. Since the first observations of Wegener (1929) about the continental drift, numerous authors (Bullard et al., 1965 ; Almeida and Black, 1967 ; Hurley et al., 1967 ; Hurley, 1968 ; Reyment and Tait, 1972 ; Krommelbein and Wenger, 1966 ; Maack, 1969) have confirmed the hypothesis of the separation of both continents, Africa and South America. [NOT CONTROLLED OCR] |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1975 |
URL: http://archimer.ifremer.fr/doc/1975/publication-5090.pdf |
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| Melguen, Marthe. |
| Facies evolution in continental margin sediments recovered on Leg 40 from the eastern South Atlantic reflects a progressive disappearance of stagnant conditions and a decrease of the terrigenous influx at the end of the Cretaceous. The Maestrichtian-Paleocene is characterized by the definitive installation of well-oxygenated oceanic conditions.The first upwelling phenomena off Southwest Africa occurred during the Eocene.Carbonate dissolution cycles have recurred several times since the Early Cretaceous. A tentative mean CCD curve for the South Atlantic since the Late Cretaceous is presented.Carbonate dissolution is considerably enhanced in upweiling areas, such as the easternmost Walvis Ridge and the Angola Margin, and is not comparable with that observed... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1978 |
URL: http://archimer.ifremer.fr/doc/1978/publication-5205.pdf |
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| Melguen, Marthe. |
| A time when France, as well as Great Britain, had a very ambitious maritime policy, the La Pérouse expedition was the only maritime expedition conceived, designed and followed at a national level by the King himself, Louis XVI. The excellence of the Expedition's preparation and of its importance in terms of scientific results, the exceptional concern of La Pérouse in the fields of data gathering and transmission, his very high quality as captain of a global expedition, made it a remarkable achievement, despite its disastrous end. |
| Tipo: Text |
Palavras-chave: D'Entrecasteaux; Cook; La Pérouse; Age of Enlightenment; Voyages of exploration; Voyages of discovery; North western America; North east Asia; Oceania; Tasmania; Pacific Ocean. |
| Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/acte-358.pdf |
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| Melguen, Marthe; Thiede, Jörn. |
| Off the Brazilian coast, the Rio Grande Rise, whose minimum depth is 600 m, acts as a barrier for deep circulation. It is crossed by a long (600 km), deep (4 600 m) and narrow (20 km wide in its central part) channel: the Vema Channel, a junction channel joining the Argentinian and Brazilian basins. Two important currents flow into the Vema Channel. The deepest, the deep Antarctic current, flows from the South to the North at a speed reaching 40 cm/s near the bottom (Le Pichon et al., 1971). Its upper limit is located at around 3 500 and 4 200 m (Le Pichon et al., 1971). Directly underneath, but flowing from the North to the South, is the deep North Atlantic current. Its estimated speed at 2 800 m deep is 15 cm/s. Its upper limit is located at around 1 000... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1975 |
URL: http://archimer.ifremer.fr/doc/1975/publication-5468.pdf |
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| Melguen, Marthe; Debrabant, Pierre; Chamley, Hervé; Maillot, Henry; Hoffert, Michel; Courtois, Chantal. |
| The sediments of six cores from the Rio Grande Rise side of the Vema Channel reflect major phases in the sedimentary history of this area since Ihe lower Miocene. Cores taken from below the present-day lysocline (approx. 4 000 m) consist essentially of calcareous oozes. The variable degree of preservation of the Foraminifera and Coccoliths in these cores indicates dissolution cycles apparently linked to Antarctic Bottom Water (A.A.B.W.) fluctuations. Cores taken below 4 000 m represent an incomplete and shortened sedimentary sequence parliculary characterized by the presence of red Clay and manganese nodules. The latter have a todorokite core and are associated with relatively indurated phillipsite-rich sediments. In one of the deeper cores an increase,... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1978 |
URL: http://archimer.ifremer.fr/doc/1978/publication-5228.pdf |
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| Pautot, Guy; Melguen, Marthe. |
| Analyses of polymetallic nodules from the central south Pacific and from the underlying sediments indicate that nodule abundance is at least partly related to the degree of carbonate dissolution, which, it self, is strongly influenced by the flow o f the Antarctic Bottom Water. The greatest nodule abundance is generally encountered in a 300 to 400 meter thick water layer situated between the lysocline and the calcite compensation depth levels.This range of depth is the first and main controlling factor of abundance. Inside this range, the bathymetry represents a secondary factor influencing both abundance and grade.Some correlations appear locally between nodule grade and abundance.Nodule grade seems to be generally related to the bottom morphology. Ni, Cu... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1979 |
URL: http://archimer.ifremer.fr/doc/1979/publication-5277.pdf |
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| Melguen, Marthe. |
| Deep-sea drilling project, launched by the U.S.A. in 1964, aiming to better understand the conditions of genesis and evolution of the ocean. The first drilling was carried out by the "Glomar Challenger" in the Gulf of Mexico in 1968. From 1968 to 1981, more than 600 sites have been drilled during 80 cruises conducted on board the "Glomar Challenger". The international phase or fourth phase of the D.S.D.P. started in 1975 and ended in 1981. Five countries joined the U.S. in this project: the U.S.S.R, Federal Germany, Japan, England and France. The P.O.D. focus: Drilling the oceanic bottoms deeper than during the first three phases of the D.S.D.P. |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/rapport-4941.PDF |
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| Noel, Denise; Melguen, Marthe. |
| Nannofacies of Leg 40 cores have been studied with two main objectives in mind: (1) describing in detail Lower Cretaceous black shales (mainly from Site 361) and (2) defining carbonate dissolution cycles. For this purpose samples from Sites 360, 361, 362, 363, and 364 have been examined using classical analysis methods (grain size, amount of CaCO3, smear slides, etc.), and the Scanning Electron Microscope (SEM). The methods of nannofacies study and interpretation used here were previously described by Noël (1969, 1970).Each sample will first be described in general, then observations will be given. Because of poor induration of the samples, only freshly broken surfaces but no polished surfaces were examined by SEM after coating with gold palladium. [NOT... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1978 |
URL: http://archimer.ifremer.fr/doc/1978/publication-5202.pdf |
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| Melguen, Marthe; Le Pichon, Xavier; Sibuet, Jean-claude. |
| A schematic model of the evolution of the South Atlantic paleoenvironment since the early Cretaceous is proposed. The reconstruction here proposed is based on all the data offered for the South Atlantic by the Deep-Sea Drilling Project. These data are integrated within the framework of Plate Tectonics. The emphasis is put on the methodology available to reconstruct the ocean crust morphology and its sedimentary cover throughout the opennig of the ocean. Paleobathymetric, paleocirculation and paleofacies maps are presented. The paleofacies maps are in great part based on a new paleo-CCD (paleo-calcite compensation depth) curve, which is tentatively proposed here for the South Atlantic. During the early Cretaceous the South Atlantic consisted of two narrow... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1978 |
URL: http://archimer.ifremer.fr/doc/1978/publication-5234.pdf |
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| Registros recuperados: 10 | |
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