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1. Carbon cycle inverse modeling suggests large changes in fractional organic burial are consistent with the carbon isotope record and may have contributed to the rise of oxygen

   https://doi.org/10.1111/gbi.12440  

   Krissansen‐Totton, Joshua ; Kipp, Michael A. ; Catling, David C. ( March 2021 , Geobiology)

   Abundant geologic evidence shows that atmospheric oxygen levels were negligible until the Great Oxidation Event (GOE) at 2.4–2.1 Ga. The burial of organic matter is balanced by the release of oxygen, and if the release rate exceeds efficient oxygen sinks, atmospheric oxygen can accumulate until limited by oxidative weathering. The organic burial rate relative to the total carbon burial rate can be inferred from the carbon isotope record in sedimentary carbonates and organic matter, which provides a proxy for the oxygen source flux through time. Because there are no large secular trends in the carbon isotope record over time, it is commonly assumed that the oxygen source flux changed only modestly. Therefore, declines in oxygen sinks have been used to explain the GOE. However, the average isotopic value of carbon fluxes into the atmosphere–ocean system can evolve due to changing proportions of weathering and outgassing inputs. If so, large secular changes in organic burial would be possible despite unchanging carbon isotope values in sedimentary rocks. Here, we present an inverse analysis using a self‐consistent carbon cycle model to determine the maximum change in organic burial since ~4 Ga allowed by the carbon isotope record and other geological proxies. We find that fractional organic burial may have increased by 2–5 times since the Archean. This happens because O₂‐dependent continental weathering of¹³C‐depleted organics changes carbon isotope inputs to the atmosphere–ocean system. This increase in relative organic burial is consistent with an anoxic‐to‐oxic atmospheric transition around 2.4 Ga without declining oxygen sinks, although these likely contributed. Moreover, our inverse analysis suggests that the Archean absolute organic burial flux was comparable to modern, implying high organic burial efficiency and ruling out very low Archean primary productivity.

    

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2. Control of Charge Carriers Trapping and Relaxation in Hematite by Oxygen Vacancy Charge: Ab Initio Non-adiabatic Molecular Dynamics

   https://doi.org/10.1021/jacs.7b02121  

   Zhou, Zhaohui ; Liu, Jin ; Long, Run ; Li, Linqiu ; Guo, Liejin ; Prezhdo, Oleg V. ( May 2017 , Journal of the American Chemical Society)
3. Inorganic carbon and oxygen dynamics in a marsh-dominated estuary: Inorganic carbon and oxygen dynamics

   https://doi.org/10.1002/lno.10614  

   Wang, Shiyu Rachel ; Di Iorio, Daniela ; Cai, Wei-Jun ; Hopkinson, Charles S. ( January 2018 , Limnology and Oceanography)
4. Hyporheic hot moments: Dissolved oxygen dynamics in the hyporheic zone in response to surface flow perturbations: DISSOLVED OXYGEN DYNAMICS IN THE HYPORHEIC ZONE

   https://doi.org/10.1002/2016WR020296  

   Kaufman, Matthew H. ; Cardenas, M. Bayani ; Buttles, Jim ; Kessler, Adam J. ; Cook, Perran L. ( August 2017 , Water Resources Research)
5. Variations in carbon burial and sediment accretion along a tidal creek in a Florida salt marsh: Florida marsh carbon burial rate variability

   https://doi.org/10.1002/lno.10652  

   Arriola, Jill M. ; Cable, Jaye E. ( November 2017 , Limnology and Oceanography)