Revisiting stepwise ocean oxygenation with authigenic barium enrichments in marine mudrocks
| العنوان: | Revisiting stepwise ocean oxygenation with authigenic barium enrichments in marine mudrocks |
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| المؤلفون: | Feifei Zhang, Yi-Bo Lin, Simon V. Hohl, Graham A. Shields, Hong-Fei Ling, Guang-Yi Wei, Tao Yang |
| المصدر: | Geology. 49:1059-1063 |
| بيانات النشر: | Geological Society of America, 2021. |
| سنة النشر: | 2021 |
| مصطلحات موضوعية: | chemistry, Geochemistry, chemistry.chemical_element, Geology, Barium, Oxygenation, Authigenic |
| الوصف: | There are current debates around the extent of global ocean oxygenation, particularly from the late Neoproterozoic to the early Paleozoic, based on analyses of various geochemical indices. We present a temporal trend in excess barium (Baexcess) contents in marine organic-rich mudrocks (ORMs) to provide an independent constraint on global ocean redox evolution. The absence of remarkable Baexcess enrichments in Precambrian (>ca. 541 Ma) ORMs suggests limited authigenic Ba formation in oxygen- and sulfate-deficient oceans. By contrast, in the Paleozoic, particularly the early Cambrian, ORMs are marked by significant Baexcess enrichments, corresponding to substantial increases in the marine sulfate reservoir and oxygenation level. Analogous to modern sediments, the Mesozoic and Cenozoic ORMs exhibit no prominent Baexcess enrichments. We suggest that variations in Baexcess concentrations of ORMs through time are linked to secular changes in the marine dissolved Ba reservoir associated with elevated marine sulfate levels and global ocean oxygenation. Further, unlike Mo, U, and Re abundances, significant Baexcess enrichments in ORMs indicate that the overall ocean oxygenation level in the early Paleozoic was substantially lower than at present. |
| تدمد: | 1943-2682 0091-7613 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::e7b2fbcffd0a8a5a046a5b6e128955bf https://doi.org/10.1130/g48825.1 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi...........e7b2fbcffd0a8a5a046a5b6e128955bf |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 19432682 00917613 |
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