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TitleTiming and tempo of the great oxidation event
 
AuthorGumsley, A P; Chamberlain, K R; Bleeker, WORCID logo; Sderlund, U; De Kock, M O; Larsson, E R; Bekker, A
SourceProceedings of the National Academy of Sciences of the United States of America vol. 114, 8, 2017 p. 1811-1816, https://doi.org/10.1073/pnas.1608824114 Open Access logo Open Access
Year2017
Alt SeriesNatural Resources Canada, Contribution Series 20182283
PublisherProceedings of the National Academy of Sciences
Documentserial
Lang.English
Mediapaper; on-line; digital
File formatpdf
ProgramGEM: Geo-mapping for Energy and Minerals
Released2017 02 06
AbstractThe first significant buildup in atmospheric oxygen, the Great Oxidation Event (GOE), began in the early Paleoproterozoic in association with global glaciations and continued until the end of the Lomagundi carbon isotope excursion ca. 2,060 Ma. The exact timing of and relationships among these events are debated because of poor age constraints and contradictory stratigraphic correlations. Here, we show that the first Paleoproterozoic global glaciation and the onset of the GOE occurred between ca. 2,460 and 2,426 Ma, ?100 My earlier than previously estimated, based on an age of 2,426 ± 3 Ma for Ongeluk Formation magmatism from the Kaapvaal Craton of southern Africa. This age helps define a key paleomagnetic pole that positions the Kaapvaal Craton at equatorial latitudes of 11¡ ± 6¡ at this time. Furthermore, the rise of atmospheric oxygen was not monotonic, but was instead characterized by oscillations, which together with climatic instabilities may have continued over the next ?200 My until ²2,250-2,240 Ma. Ongeluk Formation volcanism at ca. 2,426 Ma was part of a large igneous province (LIP) and represents a waning stage in the emplacement of several temporally discrete LIPs across a large low-latitude continental landmass. These LIPs played critical, albeit complex, roles in the rise of oxygen and in both initiating and terminating global glaciations. This series of events invites comparison with the Neoproterozoic oxygen increase and Sturtian Snowball Earth glaciation, which accompanied emplacement of LIPs across supercontinent Rodinia, also positioned at low latitude.
GEOSCAN ID310858

 
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