Semiquantitative elemental results from X-ray fluorescence (XRF) scanning of sediment cores from International Ocean Discovery Program (IODP) Site U1574 in the Vøring Plateau, Norwegian Margin, are presented in this report. XRF elemental data were collected every 1 cm from a stratigraphically complete and continuous cored section with 102% recovery from the sea bottom to ~170 meters below seafloor in Hole U1574C. We report raw element intensities (counts) for Al, Si, K, Ca, Ti, Fe, Br, Sr, and Zr and identify covariation patterns consistent with lithofacies variations. Our high-resolution XRF scanning was conducted to better characterize the sediment depositional history at Site U1574 and to aid interpretation of past environmental and oceanographic conditions in the Norwegian Margin, targeting the earliest incursion of deep water into the young North Atlantic Ocean during the Early to Middle Eocene. The high-resolution XRF data also may help improve the age-depth model for the sediment succession at Site U1574.
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This content will become publicly available on April 4, 2025
Data report: using XRF scanning–derived grain size analysis for rapid assessment of bottom current velocities on long drill cores from the southern Scotia Sea, IODP Expedition 382
Past bottom current velocities are usually determined from the sortable silt (SS) fraction of sediments. This method yields precise results, but the work associated with the preparation for and analysis of SS is very time consuming. Using data and samples from Site U1537, which was drilled during International Ocean Discovery Program (IODP) Expedition 382 (Iceberg Alley and Subantarctic Ice and Ocean Dynamics), we followed a method that allows for the reconstruction of bottom current velocities on long and highly resolved sediment records, as typically recovered during an IODP expedition. Here, we present discrete measurements of SS from Site U1537 that were used to convert X-ray fluorescence (XRF) core scanner Zr/Rb data into SS and ultimately into bottom current velocities. The use of XRF-derived SS data and current speeds allows us to generate a near-continuous high-resolution record for the past 200 ky. Because Site U1537 is located close to the Southern Antarctic Circumpolar Current Front (SACCF), this long-term reconstruction allows us to analyze and understand changes in the location of the SACCF.
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- Award ID(s):
- 1326927
- PAR ID:
- 10498860
- Publisher / Repository:
- International Ocean Discovery Program
- Date Published:
- Journal Name:
- Proceedings of the International Ocean Discovery Program Expedition reports
- Volume:
- 382
- Issue:
- 201
- ISSN:
- 2377-3189
- Subject(s) / Keyword(s):
- International Ocean Discovery Program IODP JOIDES Resolution Expedition 382 Iceberg Alley and Subantarctic Ice and Ocean Dynamics Site U1537 Dove Basin Scotia Sea Weddell Sea bottom current velocity Antarctic Circumpolar Current grain size distribution X-ray fluorescence XRF XRF scanning
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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