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  • 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
Title: 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.  more » « less
Award ID(s):
1326927
PAR ID:
10498860
Author(s) / Creator(s):
;
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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