Geochemical analysis of sediments from three coring sites in the Mediterranean, supplement to: Hübner, Andreas; de Lange, Gert Jan; 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

DOI

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.

Identifier
DOI http://dx.doi.org/doi:10.1594/PANGAEA.628536
Metadata Access http://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite3&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.628536
Provenance
Creator Halbach, Peter;Hübner, Andreas;Dittmer, J;de Lange, Gert Jan
Publisher PANGAEA - Data Publisher for Earth & Environmental Science
Publication Year 2007
Rights Creative Commons Attribution 3.0 Unported (CC-BY)
Representation
Language English
Resource Type Supplementary Collection of Datasets
Format application/zip
Discipline Earth System Research
Spatial Coverage (35N-35N,21E-22E)
Temporal Point 1998-01-30T11:59:59Z