Geochemical analysis of sediments from three coring sites in the Mediterranean


In a gravity core from the eastern Mediterranean Sea, a chemically and mineralogically distinct, 5.5-cm-thick layer is present above sapropel S-1 and overlain by hemipelagic marls. Calcite is completely absent in this exotic layer, dolomite is present only in small amounts, and the Cr concentrations are significantly enhanced. The layer was deposited primarily under reducing conditions, but the distributions of redox-sensitive elements show that a large part of the exotic layer is now oxidised by a downward-progressing oxidation front. Sediments from within the nearby anoxic, hypersaline Urania Basin are similar to those from the exotic layer, in particular in S-, C-, and O-isotope distributions of pyrite and dolomite, as well as increased Cr concentrations. Mud expulsion due to expansion of gas-rich mud is proposed to explain the presence of the exotic layer outside the Urania Basin. The deposition of an anoxic layer above S-1 shielded the sapropel from oxidation which resulted in the rare occurrence of a complete preservation of S-1 and provides the first minimum age for the start of anoxic mud accumulation in the Urania Basin.

Supplement to: Hübner, Andreas; de Lange, Gert J; Dittmer, J; Halbach, Peter (2003): Geochemistry of an exotic sediment layer above sapropel S-1: mud expulsion from the Urania Basin, eastern Mediterranean? Marine Geology, 197(1-4), 49-61

Related Identifier
Metadata Access
Creator Hübner, Andreas ORCID logo; de Lange, Gert J ORCID logo; Dittmer, J; Halbach, Peter
Publisher PANGAEA
Publication Year 2007
Funding Reference Sixth Framework Programme Crossref Funder ID 36949 Southern European Seas: Assessing and Modelling Ecosystem Changes
Rights Creative Commons Attribution 3.0 Unported;
OpenAccess true
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 2 datasets
Discipline Earth System Research
Spatial Coverage (21.471W, 35.228S, 21.500E, 35.235N); Mediterranean Sea, Urania Basin
Temporal Coverage Begin 1998-01-30T18:20:00Z
Temporal Coverage End 1998-01-31T01:31:00Z