Iron and carbon geochemistry of sediment core GeoB1401-4

DOI

Iron speciation was determined in hemiplegic sediments from a high productivity area to investigate systematically the early diagenetic reactivity of Fe. A combination of various leaching agents (1 M HCI, dithionite buffered in citrate/acetic acid, HF/H2SO4, acetic Cr(II)) was applied to sediment and extracted more than 80% of total Fe. Subsequent Fe species determination defined specific mineral fractions that are available for Fe reduction and fractions formed as products of Fe diagenesis. To determine the Fe speciation of (sheet) silicates we explored an extraction procedure (HF/H2SO4) and verified the procedure by application to standard rocks. Variations of Fe speciation of (sheet) silicates reflect the possible formation of Fe-bearing silicates in near surface sediments. The same fraction indicates a change in the primary input at greater depth, which is supported by other parameters. The Fe(II)/ Fe(III) -ratio of total sediment determined by extractions was compared with Mössbauer-spectroscopy ] at room temperature and showed agreement within 10%. M6ssbauer-spectroscopy indicates the occurrence of siderite in the presence of free sulfide and pyrite, supporting the importance of microenvironments during mineral formation. The occurrence of other Fe(II) bearing minerals such as ankerite (Ca-, Fe-, Mg-carbonate) can be presumed but remains speculative.

Supplement to: Haese, Ralf R; Wallmann, Klaus; Dahmke, Andreas; Kretzmann, U; Müller, Peter J; Schulz, Horst D (1997): Iron species determination to investigate early diagenetic reactivity in marine sediments. Geochimica et Cosmochimica Acta, 61(1), 63-72

Identifier
DOI https://doi.org/10.1594/PANGAEA.730424
Related Identifier https://doi.org/10.1016/S0016-7037(96)00312-2
Related Identifier https://nbn-resolving.org/urn:nbn:de:gbv:46-ep000102231
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.730424
Provenance
Creator Haese, Ralf R ORCID logo; Wallmann, Klaus (ORCID: 0000-0002-1795-376X); Dahmke, Andreas; Kretzmann, U; Müller, Peter J; Schulz, Horst D
Publisher PANGAEA
Publication Year 1997
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 2 datasets
Discipline Earth System Research
Spatial Coverage (9.006 LON, -6.926 LAT); Congo Fan