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| Piva, A; Asioli, A; Schneider, R; Trincardi, F; Andersen, N; Colmenero Hidalgo, E; Dennielou, Bernard; Flores, J; Vigliotti, L. |
| [1] A multiproxy integrated chronological framework, based on oxygen and carbon stable isotope stratigraphy, biostratigraphy (foraminifera and nannoplankton bioevents and foraminifer assemblage-based climate cyclicity), magnetostratigraphy, sapropel stratigraphy, and C-14 AMS radiometric dates, has been achieved for borehole PRAD1-2, collected in 185.5 m water depth in the central Adriatic. This work was carried out within the European Community project Profiles across Mediterranean Sedimentary Systems (PROMESS1). The 71.2 m long borehole spans a time interval between late MIS 11 and MIS 1 (the last 370 ka), showing a chronological resolution of 500 and 250 years per cm during interglacial and glacial intervals, respectively. At present, this record is the... |
| Tipo: Text |
Palavras-chave: Sapropel stratigraphy; Adriatic Sea; D O events; Foraminifera; Oxygen isotope stratigraphy; Late Quaternary. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3605.pdf |
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| Pichevin, L; Martinez, P; Bertrand, P; Schneider, R; Giraudeau, J; Emeis, K. |
| In the light of new surface sediment delta(15)N data collected over the Namibian shelf and slope, we examined glacial-interglacial variations of N inventory in the area of Luderitz (25 degrees 6S) by deciphering delta(15)N signals of three cores distributed from the upper to the lower continental slope. The lower slope cores display low delta(15)N during cold periods and high delta(15)N during climatic optima, akin to many other records from the world ocean, whereas the upper slope core displays a high-frequency low-amplitude delta(15)N signal without obvious glacial-interglacial variability. This dissimilarity results from the segregation of the upwelling structure in two cells, decoupling nutrient dynamics of the shelf from those beyond the shelf-edge.... |
| Tipo: Text |
Palavras-chave: Nitrogen cycling; Benguela; Climatic cycles. |
| Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/00232/34366/32796.pdf |
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| Bertrand, P; Pedersen, Tf; Schneider, R; Shimmield, G; Lallier-verges, E; Disnar, Jr; Massias, D; Villanueva, J; Tribovillard, N; Huc, Ay; Giraud, X; Pierre, C; Venec-peyre, Mt. |
| Sediments on the Namibian Margin in the SE Atlantic between water depths of similar to1000 and similar to3600 m are highly enriched in hydrocarbon-prone organic matter. Such sedimentation has occurred for more than 2 million years and is geographically distributed over hundreds of kilometers along the margin, so that the sediments of this region contain a huge concentrated stock of organic carbon. It is shown here that most of the variability in organic content is due to relative dilution by buried carbonates. This reflects both export productivity and diagenetic dissolution, not differences in either water column or bottom water anoxia and related enhanced preservation of organic matter. These observations offer a new mechanism for the formation of... |
| Tipo: Text |
Palavras-chave: Petroleum source rocks; Coastal upwelling; Deep-sea sediments; Quaternary climate; Southwestern African Margin. |
| Ano: 2003 |
URL: https://archimer.ifremer.fr/doc/00224/33553/31977.pdf |
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