The Archean atmosphere
نویسندگان
چکیده
منابع مشابه
Mass-independent fractionation of sulfur isotopes in Archean sediments: strong evidence for an anoxic Archean atmosphere.
Mass-independent fractionation (MIF) of sulfur isotopes has been reported in sediments of Archean and Early Proterozoic Age (> 2.3 Ga) but not in younger rocks. The only fractionation mechanism that is consistent with the data on all four sulfur isotopes involves atmospheric photochemical reactions such as SO2 photolysis. We have used a one-dimensional photochemical model to investigate how the...
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Xenon (Xe) is an exceptional tracer for investigating the origin and fate of volatile elements on Earth. The initial isotopic composition of atmospheric Xe remains unknown, as do the mechanisms involved in its depletion and isotopic fractionation compared with other reservoirs in the solar system. Here we present high precision analyses of noble gases trapped in fluid inclusions of Archean quar...
متن کاملLarge sulfur-isotope anomaly in nonvolcanic sulfate aerosol and its implications for the Archean atmosphere.
Sulfur-isotopic anomalies have been used to trace the evolution of oxygen in the Precambrian atmosphere and to document past volcanic eruptions. High-precision sulfur quadruple isotope measurements of sulfate aerosols extracted from a snow pit at the South Pole (1984-2001) showed the highest S-isotopic anomalies (Δ(33)S = +1.66‰ and Δ(36)S = +2‰) in a nonvolcanic (1998-1999) period, similar in ...
متن کاملImplications of present-day abiogenic methane fluxes for the early Archean atmosphere
[1] During Earth’s early history, greenhouse warming by atmospheric methane helped to maintain elevated surface temperatures. Here, we estimate the present-day abiogenic CH4 flux generated by mineral alteration (serpentinization) at midocean ridges, volcanic emissions, and geothermal sources; in addition, we assess the impact that abiogenicmethanemay have had on greenhouse warming during the ea...
متن کاملBiogeochemical Cycles of Sulfur and Nitrogen in the Archean Ocean and Atmosphere
Early geodynamic processes modeled the surface of the Earth, providing suitable environments and energy sources for the development of life. Studying the ancient biogeochemical cycles is thus a valuable way to understand the physicochemical conditions of the early environments, such as the redox state of the primitive oceans and the atmosphere. To investigate early biogeochemistries, the measur...
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ژورنال
عنوان ژورنال: Science Advances
سال: 2020
ISSN: 2375-2548
DOI: 10.1126/sciadv.aax1420