A multi-proxy approach to the paleoceanographic variability within the last glacial cycle offshore Morocco
de Jonge, C. (2010). A multi-proxy approach to the paleoceanographic variability within the last glacial cycle offshore Morocco. MSc Thesis. Universiteit Gent; MARELAC: Gent. 25 pp.
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| Beschikbaar in | Auteur |
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Documenttype: Doctoraat/Thesis/Eindwerk
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| Trefwoord |
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| Author keywords |
Gulf of Cadiz; Heinrich events; biomarker; SST (sea surface temperature); paleoclimate |
| Abstract |
A marine sediment core (MD08-3227) taken off-shore Morocco was analysed to determine the main climatic drivers on the sedimentary composition in the Pen Duick Escarpment, a mud volcano province in the Gulf of Cadiz. A multi-proxy approach, based on XRF (Fe/Al, K/Al, and K/Ti), grain size distribution (mean grain size, sorting, skewness, and kurtosis) and biomarker (TEX86, UK’37 and BIT-index) analyses was used for this paleoceanographical study. This contribution comprises the Holocene, the last glacial and the former interglacial, up to 130 ky ago. Glacial stages and Heinrich events are characterised by an enhanced aeolian input, coeval with a lower contribution of fluvial input. Stadial biogenic production points to the presence or enforcement of an upwelling system at the coring site. Also, the hypothesis of an enhanced bottom current during these stadials in the southern part of the Gulf of Cadiz is not rejected. The two sea surface temperature reconstructions do not proceed in parallel, but show a larger offset during stadials. This could be related to lateral transport or subsurface production of the alkenones. On shorter timescales, a large variability is observed that is probably related to Dansgaard-Oeschger oscillations. |
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