Detailseite
Projekt
Anorganisch- und organisch-geochemische Anzeiger für Eistransport, Flusseintrag und Frühdiagenese in quartären Sedimenten des Arktischen Ozeans
Antragsteller
Professor Dr. Hans-Jürgen Brumsack; Professor Dr. Rüdiger Stein
Fachliche Zuordnung
Paläontologie
Förderung
Förderung von 2012 bis 2017
Projektkennung
Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 224903113
The focus of this proposal lies on a high-resolution inorganic- and organic-geochemical study of central Arctic Ocean sediments and pore waters, spanning the Holocene to the Eemian Interglacial. The sediment cores and pore waters to be studied are available at the Alfred-Wegener-Institute Bremerhaven and at the University of Oldenburg. Age models covering the last ~130,000 years, as well as grain size data, mineralogy, and micropalaeontology are already available for many cores or are currently generated. Following a geochemical approach, we aim to investigate the spatial variability of sediment composition based on bulk sediment major and minor element patterns, Fe and Mn speciation, and biomarkers. The topical focus lies on the reconstruction of depositional processes (e.g. hemipelagic versus sea ice and iceberg sedimentation), changes in river input, the provenance of ice-transported material, early diagenetic processes, and the climate-controlled variability of these parameters through the last glacial-interglacial cycle. In addition, we will analyse variations in the Nd and Sr isotopic composition of the terrigenous fraction of the sediment, in specific metal-rich sediment intervals as well as in specifically extracted Mn and Fe phases. This will provide insights into the formation mechanisms of these metal enrichments in Arctic sediments. Information on the circulation pattern of Arctic deep water during deposition of the Mn-rich horizons will be obtained from the Nd isotopic composition of the extracted Mn fraction. Furthermore, we will analyse the Fe isotopic composition of selected sediment intervals to get information about material sources and potential remobilization processes within the sediment. The inorganic geochemical data sets will be compared with corresponding mineralogical and organic-geochemical proxies (in cooperation with the AWI group) in order to allow a more extended interpretation of the data in terms of paleoenvironmental change. At the same time, this spatially extended study will also serve as preliminary work for the planning of future drilling projects in the Arctic Ocean. On the basis of recent and quaternary data, a geochemical inventory will be established, which will serve as a baseline for the interpretation of paleoenvironmental conditions as well as provenance of sedimentary sequences in future IODP drillings.
DFG-Verfahren
Infrastruktur-Schwerpunktprogramme
Internationaler Bezug
Großbritannien
Beteiligte Person
Professor Dr. Christian März
