|Author(s)||Mand Kaarel1, 2, Lalonde Stefan3, Robbins Leslie J.4, Thoby Marie3, Paiste Kart2, 5, Kreitsmann Timmu2, Paiste Paarn2, Reinhard Christopher T.6, 7, Romashkin Alexandr E.8, Planavsky Noah J.4, 7, Kirsimae Kalle2, Lepland Aivo2, 5, 9, 10, Konhauser Kurt O.1|
|Affiliation(s)||1 : Univ Alberta, Dept Earth & Atmospher Sci, Edmonton, AB, Canada.
2 : Univ Tartu, Dept Geol, Tartu, Estonia.
3 : European Inst Marine Studies, CNRS, UMR6538, Lab Geosci Ocean, Plouzane, France.
4 : Yale Univ, Dept Geol & Geophys, New Haven, CT USA.
5 : UiT Arctic Univ Norway, Dept Geosci, CAGE Ctr Arctic Gas Hydrate Environm & Climate, Tromso, Norway.
6 : Georgia Tech, Sch Earth & Atmospher Sci, Atlanta, GA USA.
7 : Univ Calif Riverside, NASA, Astrobiol Inst, Alternat Earths Team, Riverside, CA 92521 USA.
8 : Karelian Sci Ctr, Inst Geol, Petrozavodsk, Russia.
9 : Geol Survey Norway NGU, Trondheim, Norway.
10 : Tallinn Univ Technol, Dept Geol, Tallinn, Estonia.
|Source||Nature Geoscience (1752-0894) (Nature Publishing Group), 2020-04 , Vol. 13 , N. 4 , P. 302-306|
|WOS© Times Cited||7|
|Abstract||The oceans probably remained well-oxygenated for millions of years after the Palaeoproterozoic Lomagundi-Jatuli Event, according to high concentrations and isotope signatures of redox-sensitive metals in the 2-billion-year-old Zaonega Formation, Russia. The approximately 2,220-2,060 million years old Lomagundi-Jatuli Event was the longest positive carbon isotope excursion in Earth history and is traditionally interpreted to reflect an increased organic carbon burial and a transient rise in atmospheric O-2. However, it is widely held that O-2 levels collapsed for more than a billion years after this. Here we show that black shales postdating the Lomagundi-Jatuli Event from the approximately 2,000 million years old Zaonega Formation contain the highest redox-sensitive trace metal concentrations reported in sediments deposited before the Neoproterozoic (maximum concentrations of Mo = 1,009 mu g g(-1), U = 238 mu g g(-1) and Re = 516 ng g(-1)). This unit also contains the most positive Precambrian shale U isotope values measured to date (maximum U-238/U-235 ratio of 0.79 parts per thousand), which provides novel evidence that there was a transition to modern-like biogeochemical cycling during the Palaeoproterozoic. Although these records do not preclude a return to anoxia during the Palaeoproterozoic, they uniquely suggest that the oceans remained well-oxygenated millions of years after the termination of the Lomagundi-Jatuli Event.|
Mand Kaarel, Lalonde Stefan, Robbins Leslie J., Thoby Marie, Paiste Kart, Kreitsmann Timmu, Paiste Paarn, Reinhard Christopher T., Romashkin Alexandr E., Planavsky Noah J., Kirsimae Kalle, Lepland Aivo, Konhauser Kurt O. (2020). Palaeoproterozoic oxygenated oceans following the Lomagundi-Jatuli Event. Nature Geoscience, 13(4), 302-306. Publisher's official version : https://doi.org/10.1038/s41561-020-0558-5 , Open Access version : https://archimer.ifremer.fr/doc/00663/77461/