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Dating the rise of atmospheric oxygen
Several lines of geological and geochemical evidence indicate that the level of atmospheric oxygen was extremely low before 2.45 billion years (Gyr) ago, and that it had reached considerable levelsExpand
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Atmospheric oxygenation three billion years ago
It is widely assumed that atmospheric oxygen concentrations remained persistently low (less than 10−5 times present levels) for about the first 2 billion years of Earth’s history. The first long-termExpand
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Low-latitude glaciation in the Palaeoproterozoic era
One of the most fundamental enigmas of the Earth's palaeoclimate concerns the temporal and spatial distributions of Precambrian glaciations. Through four billion years of Precambrian history,Expand
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Evidence for oxygenic photosynthesis half a billion years before the Great Oxidation Event
The early Earth was characterized by the absence of oxygen in the ocean–atmosphere system, in contrast to the well-oxygenated conditions that prevail today. Atmospheric concentrations first rose toExpand
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Rapid oxygenation of Earth’s atmosphere 2.33 billion years ago
Continuous multiple sulfur isotope profiles from South African rocks pinpoint the Great Oxygenation Event in the geologic record. Molecular oxygen (O2) is, and has been, a primary driver ofExpand
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Facies relations, depositional environments and diagenesis in a major early Proterozoic stromatolitic carbonate platform to basinal sequence, Campbellrand Subgroup, Transvaal Supergroup, Southern
The Campbellrand Subgroup and its correlative, the Malmani Subgroup of the Transvaal Supergroup, represent a major 2300–2600 Ma old carbonate buildup. It is on average between 1500 and 1700 m thickExpand
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Chemostratigraphy of the Paleoproterozoic Duitschland Formation, South Africa: Implications for Coupled Climate Change and Carbon Cycling
The Paleoproterozoic Duitschland Formation lies stratigraphically beneath the Timeball Hill Formation, which contains the only unequivocal glacial unit of this era in the Transvaal Basin, SouthExpand
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Sedimentology and geochemistry of the glaciogenic late Proterozoic Rapitan Iron-Formation in Canada
The Rapitan iron-formation in the Northwest Territories and Yukon of Canada was formed between 755 and 730 Ma. This iron-formation is approximately coeval with several other extensive iron-formationsExpand
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Evidence for a gradual rise of oxygen between 2.6 and 2.5 Ga from Mo isotopes and Re-PGE signatures in shales
Abstract Concerning the question of how and when free oxygen started to accumulate in the Earth’s atmosphere and hydrosphere, we report Mo concentrations and isotopic compositions as well as PlatinExpand
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Geochemistry and sedimentology of a facies transition from limestone to iron-formation deposition in the early Proterozoic Transvaal Supergroup, South Africa
This study deals with the geochemistry and sedimentology of a facies transition from interbedded carbonate-shale to banded iron-formation in the Campbellrand carbonate sequence to the overlyingExpand
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