Sapropels in the Mediterranean Sea

DOI

Eastern Mediterranean sediments are characterized by cyclic deposition of organic-rich sediments known as sapropels. Enhanced primary productivity combined with bottom water oxygen depletion are thought to be the main drivers for sapropel deposition. We selected sapropel layers from a suite of ODP-Leg 160 cores, and applied a set of geochemical proxies to determine paleo-productivity variations, redox conditions of the water column during deposition, and provenance of detrital material.High sedimentary Ba/Al and Corg contents indicate enhanced primary production, whereas the sedimentary La/Lu ratio, points to an enhanced contribution from a North African riverine source, during sapropel formation. These features are especially pronounced on Sapropels S5 and S7, deposited during a particularly warm climatic interval. This indicates a more intense North African drainage/weathering and consequently run-off for those sapropels that have the most enhanced expression of productivity too. Correspondingly, the latter has also resulted in bottom water redox conditions that have been more severe during these sapropels than during others.Deepwater formation from Adriatic and Aegean areas, thought to be mainly controlled by sustained cooling of preconditioned surface waters, triggers the onset of bottomwater ventilation, thus sapropel duration. Our data, therefore, suggest that the intensity of sapropel formation is determined by the North African monsoonal system, whereas their duration is directed by northern borderlands climatic conditions.

Supplement to: Gallego-Torres, David; Martinez-Ruiz, Francisca C; de Lange, Gert J; Jiménez-Espejo, Francisco Jose; Ortega-Huertas, M (2010): Trace-elemental derived paleoceanographic and paleoclimatic conditions for Pleistocene Eastern Mediterranean sapropels. Palaeogeography, Palaeoclimatology, Palaeoecology, 293(1-2), 76-89

Identifier
DOI https://doi.org/10.1594/PANGAEA.777777
Related Identifier IsSupplementTo https://doi.org/10.1016/j.palaeo.2010.05.001
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.777777
Provenance
Creator Gallego-Torres, David; Martinez-Ruiz, Francisca C ORCID logo; de Lange, Gert J ORCID logo; Jiménez-Espejo, Francisco Jose; Ortega-Huertas, M ORCID logo
Publisher PANGAEA
Publication Year 2010
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 3 datasets
Discipline Earth System Research
Spatial Coverage (17.750W, 33.797S, 32.725E, 36.261N); Eastern Basin
Temporal Coverage Begin 1995-03-17T00:00:00Z
Temporal Coverage End 1995-04-16T00:00:00Z