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| Pujos, M; Latouche, C; Maillet, N. |
| Marine muds deposited on the French Guiana coast mostly originate in the Amazon. Recent sediments are composed of (a) illite (33 %) and chlorite (13 %) of Andean mountain origin; and (b) kaolinite (28 %) and smectite (26 %), principally from the Amazonian lowlands but also from the Guiana Shield. In the coastal mud prism, high-resolution seismic profiles, together with sedimentological, micropaleontological and soil engineering studies, supplemented by C-14 dates, permitted a stratigraphic interpretation of eight cores. Three episodes have been determined on the basis of clay-mineral variations related to Amazonian lowland, Andean and Guiana shield sources. The older episodes 3 (3000-1700 y BP) and 2 (1700-1000 y BP) are predominantly characterized by... |
| Tipo: Text |
Palavras-chave: Late quaternary; French Guiana; Shelf; Clay minerals; ENSO. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00094/20506/18175.pdf |
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| Hatin, T.; Crosta, X.; Le Herisse, A.; Droz, L.; Marsset, Tania. |
| Changes in siliceous productivity in the eastern Equatorial Atlantic Ocean, off the Western African margin, over the last several glacial cycles have been either related to global-to-regional oceanographic changes (upwelling intensity) or climate changes (precipitation and river discharge). Based on diatom assemblages in core KZAI-02, located to the south of the mouth of the Congo River, integrated with a selection of geochemical proxies, we show that siliceous productivity in the southeastern Angola Basin responded to non-linear interactions between both oceanographic and climate changes over the last 190,000 years. High diatom accumulation rates were recorded in the middle part of MIS 6, in cold substage MIS 5d and in MIS 3-2. During these intervals,... |
| Tipo: Text |
Palavras-chave: Diatoms; Productivity; Late quaternary; Millennial time scale; Congo fan area. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00363/47402/47394.pdf |
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