Articles | Volume 20, issue 24
https://doi.org/10.5194/bg-20-5003-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-20-5003-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Dec 2023
Research article |
| 19 Dec 2023
| 19 Dec 2023
Revisiting the applicability and constraints of molybdenum- and uranium-based paleo redox proxies: comparing two contrasting sill fjords
Environmental Geochemistry Group, Department of Geography and Geosciences, Faculty of Science, University of Helsinki, Helsinki, 00560, Finland
Martijn Hermans
Environmental Geochemistry Group, Department of Geography and Geosciences, Faculty of Science, University of Helsinki, Helsinki, 00560, Finland
Baltic Sea Centre, Stockholm University, Stockholm, 114 18, Sweden
Sami A. Jokinen
Marine Geology, Geological Survey of Finland (GTK), Espoo, 02151, Finland
Inda Brinkmann
Department of Geology, Faculty of Science, Lund University, Lund, 223 62, Sweden
Department of Glaciology and Climate, Geological Survey of Denmark and Greenland, Copenhagen, 1350, Denmark
Helena L. Filipsson
Department of Geology, Faculty of Science, Lund University, Lund, 223 62, Sweden
Tom Jilbert
Environmental Geochemistry Group, Department of Geography and Geosciences, Faculty of Science, University of Helsinki, Helsinki, 00560, Finland
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Short summary
Seawater naturally contains trace metals such as Mo and U, which accumulate under low oxygen conditions on the seafloor. Previous studies have used sediment Mo and U contents as an archive of changing oxygen concentrations in coastal waters. Here we show that in fjords the use of Mo and U for this purpose may be impaired by additional processes. Our findings have implications for the reliable use of Mo and U to reconstruct oxygen changes in fjords.
Seawater naturally contains trace metals such as Mo and U, which accumulate under low oxygen...
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