1. Early Paleocene Paleoceanography and Export Productivity in the Chicxulub Crater
- Author
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Lowery C.M., Jones H.L., Bralower T.J., Cruz L.P., Gebhardt C., Whalen M.T., Chenot E., Smit J., Phillips M.P., Choumiline K., Arenillas I., Arz J.A., Garcia F., Ferrand M., Gulick S.P.S., Christeson G., Claeys P., Cockell C., Coolen M., Ferrière L., Goto K., Green S., Grice K., Kring D., Lofi J., Mellett C., Morgan J., Ocampo-Torres R., Pickersgill A., Poelchau M., Rae A., Rasmussen C., Rebolledo-Vieyra M., Riller U., Sato H., Schaefer B., Tikoo S., Tomioka N., Urrutia-Fucugauchi J., Wittmann A., Xiao L., Yamaguchi K., Zylberman W., Expedition 364 Science Party, Institute for Geophysics, University of Texas, University of Texas at Austin [Austin], Department of Geosciences [PennState], College of Earth and Mineral Sciences, Pennsylvania State University (Penn State), Penn State System-Penn State System-Pennsylvania State University (Penn State), Penn State System-Penn State System, Center for Marine Environmental Sciences [Bremen] (MARUM), Universität Bremen, Instituto de Geofisica [Mexico], Universidad Nacional Autónoma de México (UNAM), Alfred Wegener Institute for Polar and Marine Research (AWI), Department of Geosciences, University of Alaska [Fairbanks] (UAF), Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Institut Polytechnique LaSalle Beauvais, Faculty of Earth and Life Sciences [Amsterdam] (FALW), Vrije Universiteit Amsterdam [Amsterdam] (VU), Department of Earth Sciences [Riverside], University of California [Riverside] (UCR), University of California-University of California, Departamento de Ciencias de la Tierra, University of Zaragoza - Universidad de Zaragoza [Zaragoza], Instituto Universitario en investigación en Ciencias Ambientales de Aragón (IUCA), Biogéosciences [UMR 6282] [Dijon] (BGS), Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Centre National de la Recherche Scientifique (CNRS), Department of Geological Sciences [Austin], Jackson School of Geosciences (JSG), University of Texas at Austin [Austin]-University of Texas at Austin [Austin], Center for Planetary Systems Habitability, University of Texas at Austin [Austin]-Jackson School of Geosciences, and Geology and Geochemistry
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bepress|Physical Sciences and Mathematics|Earth Sciences|Paleontology ,bepress|Physical Sciences and Mathematics ,bepress|Physical Sciences and Mathematics|Earth Sciences|Sedimentology ,010506 paleontology ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,bepress|Physical Sciences and Mathematics|Earth Sciences ,EarthArXiv|Physical Sciences and Mathematics|Earth Sciences ,010502 geochemistry & geophysics ,Oceanography ,01 natural sciences ,Foraminifera ,Water column ,Impact crater ,Paleoceanography ,Phytoplankton ,Photic zone ,14. Life underwater ,SDG 14 - Life Below Water ,EarthArXiv|Physical Sciences and Mathematics|Earth Sciences|Sedimentology ,0105 earth and related environmental sciences ,biology ,Terrigenous sediment ,Paleontology ,EarthArXiv|Physical Sciences and Mathematics|Earth Sciences|Geochemistry ,15. Life on land ,EarthArXiv|Physical Sciences and Mathematics|Earth Sciences|Paleontology ,biology.organism_classification ,humanities ,EarthArXiv|Physical Sciences and Mathematics ,Productivity (ecology) ,13. Climate action ,[SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy ,Environmental science ,bepress|Physical Sciences and Mathematics|Earth Sciences|Geochemistry - Abstract
The Chicxulub impact caused a crash in productivity in the world''s oceans which contributed to the extinction of ~75% of marine species. In the immediate aftermath of the extinction, export productivity was locally highly variable, with some sites, including the Chicxulub crater, recording elevated export production. The long-term transition back to more stable export productivity regimes has been poorly documented. Here, we present elemental abundances, foraminifer and calcareous nannoplankton assemblage counts, total organic carbon, and bulk carbonate carbon isotope data from the Chicxulub crater to reconstruct changes in export productivity during the first 3 Myr of the Paleocene. We show that export production was elevated for the first 320 kyr of the Paleocene, declined from 320 kyr to 1.2 Myr, and then remained low thereafter. A key interval in this long decline occurred 900 kyr to 1.2 Myr post impact, as calcareous nannoplankton assemblages began to diversify. This interval is associated with fluctuations in water column stratification and terrigenous flux, but these variables are uncorrelated to export productivity. Instead, we postulate that the turnover in the phytoplankton community from a post-extinction assemblage dominated by picoplankton (which promoted nutrient recycling in the euphotic zone) to a Paleocene pelagic community dominated by relatively larger primary producers like calcareous nannoplankton (which more efficiently removed nutrients from surface waters, leading to oligotrophy) is responsible for the decline in export production in the southern Gulf of Mexico. © 2021. American Geophysical Union. All Rights Reserved.
- Published
- 2021
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