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230Th Normalization: New Insights on an Essential Tool for Quantifying Sedimentary Fluxes in the Modern and Quaternary Ocean230Th normalization is a valuable paleoceanographic tool for reconstructing high‐resolution sediment fluxes during the late Pleistocene (last ~500,000 years). As its application has expanded to ever more diverse marine environments, the nuances of 230Th systematics, with regard to particle type, particle size, lateral advective/diffusive redistribution, and other processes, have emerged. We synthesized over 1000 sedimentary records of 230Th from across the global ocean at two time slices, the late Holocene (0–5,000 years ago, or 0–5 ka) and the Last Glacial Maximum (18.5–23.5 ka), and investigated the spatial structure of 230Th‐normalized mass fluxes. On a global scale, sedimentary mass fluxes were significantly higher during the Last Glacial Maximum (1.79–2.17 g/sq.cmkyr, 95% confidence) relative to the Holocene (1.48–1.68 g/sq.cmkyr, 95% confidence). We then examined the potential confounding influences of boundary scavenging, nepheloid layers, hydrothermal scavenging, size‐dependent sediment fractionation, and carbonate dissolution on the efficacy of 230Th as a constant flux proxy. Anomalous 230Th behavior is sometimes observed proximal to hydrothermal ridges and in continental margins where high particle fluxes and steep continental slopes can lead to the combined effects of boundary scavenging and nepheloid interference. Notwithstanding these limitations, we found that 230Th normalization is a robust tool for determining sediment mass accumulation rates in the majority of pelagic marine settings (>1,000 m water depth).


Document ID
20200002286
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Costa, Kassandra M.
(Woods Hole Oceanographic Institution Woods Hole, MA, United States)
Hayes, Christopher T.
(University of Southern Mississippi Bay Saint Louis, MS, United States)
Anderson, Robert F.
(Columbia University Palisades, NY, United States)
Pavia, Frank J.
(Columbia University Palisades, NY, United States)
Bausch, Alexandra
(Columbia University Palisades, NY, United States)
Deng, Feifei
(University of Oxford Oxford, England, United Kingdom)
Dutay, Jean‐Claude
(Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette, France)
Geibert, Walter
(Alfred-Wegener-Inst. for Polar Research Bremerhaven, Germany)
Heinze, Christoph
(University of Bergen Bergen, Norway)
Henderson, Gideon
(University of Oxford Oxford, England, United Kingdom)
Hillaire‐Marcel, Claude
(Université du Québec à Montréal Montreal, Quebec, Canada)
Hoffmann, Sharon
(University of North Carolina at Wilmington (UNCW) Wilmington, NC, United States)
Jaccard, Samuel L.
(Bern Univ. Bern, Switzerland)
Jacobel, Allison W.
(Brown Univ. Providence, RI, United States)
Kienast, Stephanie S.
(Dalhousie Univ. Halifax, Nova Scotia, Canada)
Kipp, Lauren
(Columbia University Palisades, NY, United States)
Lerner, Paul
(Columbia University New York, NY, United States)
Lippold, Jörg
(Universität Heidelberg Heidelberg, Germany)
Lund, David
(Connecticut Univ. Groton, CT, United States)
Marcantonio, Franco
(Texas A&M Univ. Temple, TX, United States)
McGee, David
(Massachusetts Institute of Technology (MIT) Cambridge, MA, United States)
McManus, Jerry F.
(Columbia University Palisades, NY, United States)
Mekik, Figen
(Grand Valley State Univ. Allendale, MI, United States)
Middleton, Jennifer L.
(Columbia University Palisades, NY, United States)
Missiaen, Lise
(University of New South Wales Kensington, Australia)
Not, Christelle
(University of Hong Kong Pokfulam, Hong Kong)
Pichat, Sylvain
(Université de Lyon Lyon, France)
Robinson, Laura F.
(University of Bristol Bristol, United Kingdom)
Rowland, George H.
(University of Bristol Bristol, United Kingdom)
Roy‐Barman, Matthieu
(Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette, France)
Tagliabue, Alessandro
(University of Liverpool Liverpool, United Kingdom)
Torfstein, Adi
(Hebrew University of Jerusalem Jerusalem, Israel)
Winckler, Gisela
(Columbia University Palisades, NY, United States)
Zhou, Yuxin
(Columbia University Palisades, NY, United States)
Date Acquired
April 7, 2020
Publication Date
January 27, 2020
Publication Information
Publication: Paleoceanography and Paleoclimatology
Publisher: American Geophysical Union
Volume: 35
Issue: 2
e-ISSN: 2572-4525
Subject Category
Geosciences (General)
Report/Patent Number
GSFC-E-DAA-TN79072
Funding Number(s)
CONTRACT_GRANT: DP180100048
CONTRACT_GRANT: NNH15CO48B
CONTRACT_GRANT: PP002P2_144811
CONTRACT_GRANT: NE/L002434/1
CONTRACT_GRANT: PP00P2_172915
Distribution Limits
Public
Copyright
Use by or on behalf of the US Gov. Permitted.
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