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Title: Data report: X-ray fluorescence scanning of sediment cores, IODP Expedition 390/393 Site U1560, South Atlantic Transect
International Ocean Discovery Program (IODP) Expeditions 390C, 395E, 390, and 393 recovered deepwater sediments from the western flank of the Mid-Atlantic Ridge in the South Atlantic Ocean along the South Atlantic Transect (SAT) at ~31°S. Collectively, these expeditions recovered ~2 km of sediment cores that have the potential to capture key features of Cenozoic climate change. In this report, we show semiquantitative bulk elemental results from X-ray fluorescence (XRF) scanning of the sediment cores from IODP Site U1560 recovered during Expeditions 395E and 393. The oceanic basement at this site is ~15 My old, making it the second youngest of the SAT sites located west of the Mid-Atlantic Ridge. Here, XRF data are compared with pass-through magnetic susceptibility and natural gamma radiation of the sediment cores, measured aboard JOIDES Resolution. The resulting trends and correlations highlight elemental variations through time, mainly reflecting lithologic and compositional differences. At Site U1560, Ca counts reflect the occurrence of nannofossil ooze, which is the dominant lithology for the whole site. In the Miocene-aged Lithologic Units IE–IA from 140 to 50 m core composite depth below seafloor (CCSF), several high-intensity spikes of detrital elements (i.e., Fe, Ti, Al, Si, and Zr) correspond to intervals of clay-rich nannofossil ooze. Detrital elemental counts in the entire Pliocene record (50 to ~25 m CCSF) are the lowest. A sharp shift is observed at the Pliocene/Pleistocene boundary at ~25 m CCSF, with the uppermost Pleistocene record showing high-frequency and high-intensity variations in siliciclastic elements, which correlates well with the pass-through magnetic susceptibility.  more » « less
Award ID(s):
1326927
PAR ID:
10501360
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; « less
Publisher / Repository:
International Ocean Discovery Program
Date Published:
Journal Name:
Proceedings of the International Ocean Discovery Program Expedition reports
Volume:
390/393
Issue:
205
ISSN:
2377-3189
Subject(s) / Keyword(s):
International Ocean Discovery Program IODP JOIDES Resolution Expedition 390 Expedition 393 Expedition 395E South Atlantic Transect Site U1560 X-ray fluorescence core scanning XRF core scanning Middle Miocene Climatic Optimum Miocene Pliocene Pleistocene Neogene
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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