Globally asynchronous sulphur isotope signals require re-definition of the Great Oxidation Event

Autor(es):Mostrar menos -

Philippot, Pascal ^{[1, 2]} ; Avila, Janaina N. ^[3] ; Killingsworth, Bryan A. ^[4] ; Tessalina, Svetlana ^[5] ; Baton, Franck ^[1] ; Caquineau, Tom ^[1] ; Muller, Elodie ^[1] ; Pecoits, Ernesto ^{[1, 6]} ; Cartigny, Pierre ^[1] ; Lalonde, Stefan V. ^[4] ; Ireland, Trevor R. ^[3] ; Thomazo, Christophe ^[7] ; van Kranendonk, Martin J. ^[8] ; Busigny, Vincent ^[1]

Afiliação do(s) autor(es)

^[1] Univ Paris Diderot, Inst Phys Globe Paris, Sorbonne Paris Cite, CNRS, 1 Rue Jussieu, F-75238 Paris - France

^[2] Univ Montpellier, Geosci Montpellier, CNRS, UMR 5243, F-34095 Montpellier - France

^[3] Australian Natl Univ, Res Sch Earth Sci, 142 Mills Rd, Canberra, ACT 2601 - Australia

^[4] European Inst Marine Studies, UMR6538, Lab Geociences Ocean, Pl Nicolas Copernic, F-29280 Plouzane - France

^[5] Curtin Univ, John de Laeter Ctr Isotope Res, Fac Sci & Engn, Bld 301, GPO Box U1987, Perth, WA 6845 - Australia

^[6] Uruguay Technol Univ UTEC, Dept Environm Sci, Francisco Antonio Maciel 97000, Durazno - Uruguay

^[7] Univ Bourgogne Franche Comte, UMR Biogeosci UB6282, CNRS, 6 Bd Gabriel, F-21000 Dijon - France

^[8] Univ New South Wales, Sch Biol Earth & Environm Sci, Kensington, NSW 2052 - Australia

• Tipo de documento: Artigo Científico
• Fonte: NATURE COMMUNICATIONS; v. 9, JUN 8 2018.
• Citações Web of Science: 17

Resumo

The Great Oxidation Event (GOE) has been defined as the time interval when sufficient atmospheric oxygen accumulated to prevent the generation and preservation of mass-independent fractionation of sulphur isotopes (MIF-S) in sedimentary rocks. Existing correlations suggest that the GOE was rapid and globally synchronous. Here we apply sulphur isotope analysis of diagenetic sulphides combined with U-Pb and Re-Os geochronology to document the sulphur cycle evolution in Western Australia spanning the GOE. Our data indicate that, from similar to 2.45 Gyr to beyond 2.31 Gyr, MIF-S was preserved in sulphides punctuated by several episodes of MIF-S disappearance. These results establish the MIF-S record as asynchronous between South Africa, North America and Australia, argue for regional-scale modulation of MIF-S memory effects due to oxidative weathering after the onset of the GOE, and suggest that the current paradigm of placing the GOE at 2.33-2.32 Ga based on the last occurrence of MIF-S in South Africa should be re-evaluated. (AU)

• Processo FAPESP: 15/16235-2 - Evolução da vida e oxigenação da Terra primitiva: uma perspectiva a partir da América do Sul
• Beneficiário: Pascal Andre Marie Philippot
• Modalidade de apoio: Auxílio à Pesquisa - Programa SPEC