PP011-07
The Composition and Flux of Seafloor Sediments in the Global Ocean
Tuesday, 8 December 2020: 05:54
Virtual
Christopher T Hayes1, Kassandra Costa2, Eva Calvo3, Zanna Chase4, Ludmila L'vovna Demina5, Jean-Claude Dutay6, Christopher R German7, Lars-Eric Heimbuerger-Boavida8, Sam Jaccard9, Allison W Jacobel10, Karen Elizabeth Kohfeld11, Marina D Kravchishina5, Jörg Lippold12, Figen Mekik13, Lise Missiaen14, Frank J Pavia15, Adina Paytan16, Mariia Petrova17, Rut Pedrosa Pamies18, Shaily Rahman1, Laura Robinson19, Matthieu Roy-Barman20, Anna Sanchez-Vidal21, Alan M Shiller22, Alessandro Tagliabue23, Allyson Tessin24, Marco van Hulten25 and Jing Zhang26, (1)University of Southern Mississippi, Stennis Space Center, MS, United States, (2)Woods Hole Oceanographic Institution, Department of Geology & Geophysics, Woods Hole, MA, United States, (3)ICM-CSIC, Barcelona, Spain, (4)University of Tasmania, Institute for Marine and Antarctic Studies, Hobart, TAS, Australia, (5)Shirshov Institute of Oceanology, Moscow, Russia, (6)LSCE Laboratoire des Sciences du Climat et de l'Environnement, Gif-Sur-Yvette Cedex, France, (7)WHOI, Woods Hole, MA, United States, (8)MIO-CNRS, Marseille, France, (9)University of Bern, Institute of Geological Sciences & Oeschger Center for Climate Change Research, Bern, Switzerland, (10)Brown University, Department of Earth, Environmental and Planetary Sciences, Providence, RI, United States, (11)Simon Fraser University, School of Resource and Environmental Management and School of Environmental Science, Burnaby, BC, Canada, (12)University of Heidelberg, Heidelberg, Germany, (13)Grand Valley State University, Allendale, MI, United States, (14)University of New South Wales, Sydney, Australia, (15)California Institute of Technology, Pasadena, CA, United States, (16)UCSC-Inst Marine Sciences, Santa Cruz, CA, United States, (17)Mediterranean Institute of Oceanography, Marseille Cedex 09, France, (18)Marine Biological Laboratory, The Ecosystems Center, Woods Hole, MA, United States, (19)University of Bristol, Bristol, United Kingdom, (20)Universite Paris-Saclay, Gif sur Yvette, France, (21)Universitat de Barcelona, GRC Geociències Marines, Departament de Dinàmica de la Terra i de l’Oceà, Barcelona, Spain, (22)University of Southern Mississippi, Marine Science, Stennis Space Center, MS, United States, (23)University of Liverpool, Earth, Ocean and Ecological Sciences, Liverpool, L69, United Kingdom, (24)University of Southern Mississippi, Stennis Space Center, United States, (25)University of Bergen, Geophysical Institute, Bergen, Norway, (26)East China Normal University, Shanghai, China
Abstract:
Quantitative knowledge about the burial of sedimentary components at the seafloor has wide-ranging implications in ocean science, from global climate to continental weathering. The use of
230Th-normalized fluxes reduces uncertainties that many prior studies faced by accounting for the effects of sediment redistribution by bottom currents and minimizing the impact of age model uncertainty. Here we employ a recently compiled global data set of
230Th-normalized fluxes with an updated database of seafloor surface sediment composition to derive global maps of the burial flux of calcium carbonate, biogenic opal, total organic carbon (TOC), non-biogenic material, iron, mercury, and excess barium (Ba xs). The spatial patterns of burial of the major components are consistent with prior work, but the new quantitative estimates allow evaluations of elemental budgets including many marginal seas that were previously data gaps. Our globally-integrated marine burial fluxes are 139 Tg C/yr CaCO
3, 179 Tg Si/yr opal, 21Tg C/yr TOC, and 220 Mg Hg/yr. Sedimentary Fe fluxes reflect a mixture of sources including lithogenic material, hydrothermal inputs and authigenic phases. The fluxes of some commonly used paleo-productivity proxies (TOC, biogenic opal, and Ba xs) are not well-correlated geographically with satellite-based productivity estimates on the global scale. Our new compilation of sedimentary fluxes provides more detailed information on burial fluxes, which should lead to substantial improvements in the understanding of how preservation affects these paleoproxies.
