FN Archimer Export Format PT J TI Late Eocene onset of the Proto-Antarctic Circumpolar Current BT AF Sarkar, Sudipta Basak, Chandranath Frank, Martin Berndt, Christian Huuse, Mads Badhani, Shray Bialas, Joerg AS 1:1;2:2;3:3;4:3;5:4;6:5;7:3; FF 1:;2:;3:;4:;5:;6:PDG-REM-GM-LAD;7:; C1 Department of Earth and Climate Science, Indian Institute of Science Education and Research Pune, Pune, 411008, India Department of Geological Sciences, California State University, Bakersfield, CA, 93311, USA GEOMAR Helmholtz Centre for Ocean Research, Kiel, 24148, Germany School of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK IFREMER, Unité de Recherche Géosciences Marines, Centre de Bretagne, 1625 Route de Sainte-Anne, 29280, Plouzané, France C2 IISER, INDIA UNIV CALIF STATE, USA IFM GEOMAR, GERMANY UNIV MANCHESTER, UK IFREMER, FRANCE SI BREST SE PDG-REM-GM-LAD IN WOS Ifremer UPR DOAJ copubli-europe copubli-int-hors-europe copubli-sud IF 3.998 TC 19 UR https://archimer.ifremer.fr/doc/00506/61778/65775.pdf https://archimer.ifremer.fr/doc/00506/61778/65777.pdf LA English DT Article AB The formation of the Antarctic Circumpolar Current (ACC) is critical for the evolution of the global climate, but the timing of its onset is not well constrained. Here, we present new seismic evidence of widespread Late Eocene to Oligocene marine diagenetic chert in sedimentary drift deposits east of New Zealand indicating prolonged periods of blooms of siliceous microorganisms starting ~36 million years ago (Ma). These major blooms reflect the initiation of the arrival and upwelling of northern-sourced, nutrient-rich deep equatorial Pacific waters at the high latitudes of the South Pacific. We show that this change in circulation was linked to the initiation of a proto-ACC, which occurred ~6 Ma earlier than the currently estimated onset of the ACC at 30 Ma. We propose that the associated increased primary productivity and carbon burial facilitated atmospheric carbon dioxide reduction contributing to the expansion of Antarctic Ice Sheet at the Eocene-Oligocene Transition. PY 2019 PD JUN SO Scientific Reports SN 2045-2322 PU Springer Science and Business Media LLC VL 9 IS 1 UT 000475293200027 DI 10.1038/s41598-019-46253-1 ID 61778 ER EF