|
|
|
|
|
Eynaud, F; Zaragosi, S; Scourse, J; Mojtahid, M; Bourillet, Jean-francois; Hall, I. R.; Penaud, A; Locascio, M; Reijonen, A. |
[1] We have compiled results obtained from four high sedimentation rate hemipelagic sequences from the Celtic sector of the NW European margin ( NE Atlantic) to investigate the paleoceanographic and paleoclimatic evolution of the area over the last few climatic cycles. We focus on periods characteristic of deglacial transitions. We adopt a multiproxy sedimentological, geochemical, and micropaleontological approach, applying a sampling resolution down to ten microns for specific intervals. The investigation demonstrates the relationships between the Bay of Biscay hydrography and the glacial/deglacial history of both the proximal British-Irish Ice Sheet (BIIS) and the western European continent. We identify recurrent phases of laminae deposition concurrent... |
Tipo: Text |
Palavras-chave: Paleoceanography : micropaleontology; Paleoceanography : abrupt/rapid climate change; Paleoceanography : glacial; Planktonic microfossils; Ice rafted detritus; Freshwater pulse/discharge; Laminated sediments; Glacial terminations; Celtic margin. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2606.pdf |
| |
|
|
Chang, Alice S.; Pichevin, Laetitia; Pedersen, Thomas F.; Gray, Victoria; Ganeshram, Raja. |
A high-resolution, 55 kyr long record of chalcophile and redox-sensitive trace element accumulation (Ag, Cd, Re, and Mo) from MD02-2515, western Guaymas Basin, is investigated in conjunction with patterns in stratigraphy and productivity. High opal concentrations (~59 wt. %), representing increased diatom production, coincide with laminated sediments and dilute the concentrations of organic carbon (Corg) and metals. A similarity between opal and normalized Corg, Ag, and Cd concentrations suggests delivery to the sediments by diatom export production, while patterns in normalized Re and Mo accumulation suggest a different emplacement mechanism. Although Mo enrichment in organic-rich, laminated sediments typically represents anoxic conditions at other... |
Tipo: Text |
Palavras-chave: Productivity; Redox; Trace elements; Laminated sediments; Guaymas Basin; Northeast Pacific Ocean. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00294/40566/39461.pdf |
| |
|
|
Denis, Delphine; Crosta, X; Zaragosi, S; Romero, O; Martin, B; Mas, Virginie. |
A 40 m long sediment core covering the 1000-9600 years BP period was retrieved from the Dumont d'Urville Trough off Adelie Land, East Antarctica, during the MD 130-Images X-CADO cruise. This sedimentary sequence allows the documentation of changes in climate seasonality during the Holocene. Here we show preliminary results of diatom communities, lithic grain distribution and titanium content measured on two 30 cm long sequences of thin sections. The two sequences originate from two different climate regimes, the colder Neoglacial and the warmer Hypsithermal. Proxies were measured at microscale resolution on 25 laminations for the Neoglacial and 14 laminations for the Hypsithermal. The two sequences reveal alternating light-green and dark-green laminae.... |
Tipo: Text |
Palavras-chave: East Antarctica; Sea ice; Seasonality; Diatom ooze; Laminated sediments; Holocene; Adelie Land. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2275.pdf |
| |
|
|
|