Oxidation of the Ediacaran Ocean

  title={Oxidation of the Ediacaran Ocean},
  author={David A. Fike and John P. Grotzinger and Lisa M. Pratt and Roger Everett Summons},
Oxygenation of the Earth’s surface is increasingly thought to have occurred in two steps. The first step, which occurred ∼2,300 million years (Myr) ago, involved a significant increase in atmospheric oxygen concentrations and oxygenation of the surface ocean. A further increase in atmospheric oxygen appears to have taken place during the late Neoproterozoic period (∼800–542 Myr ago). This increase may have stimulated the evolution of macroscopic multicellular animals and the subsequent… Expand
Tracing the stepwise oxygenation of the Proterozoic ocean
A new perspective on ocean oxygenation is presented based on the authigenic accumulation of the redox-sensitive transition element molybdenum in sulphidic black shales, which reflects a greatly expanded oceanic reservoir due to oxygenation of the deep ocean and corresponding decrease in sulphide conditions in the sediments and water column. Expand
Ocean oxygenation in the wake of the Marinoan glaciation
The data provide evidence for an early Ediacaran oxygenation event, which pre-dates the previous estimates for post-Marinoan oxygenation by more than 50 million years, and seem to support a link between the most severe glaciations in Earth’s history, the oxygenation of the Earth's surface environments, and the earliest diversification of animals. Expand
A Stratified Redox Model for the Ediacaran Ocean
A detailed spatial and temporal record of Ediacaran ocean chemistry for the Doushantuo Formation in the Nanhua Basin, South China is presented, finding evidence for a metastable zone of euxinic (anoxic and sulfidic) waters impinging on the continental shelf and sandwiched within ferruginous [Fe(II)-enriched] deep waters. Expand
The Neoproterozoic oxygenation event: Environmental perturbations and biogeochemical cycling
Abstract The oxygen content of the Earth's surface environment is thought to have increased in two broad steps: the Great Oxygenation Event (GOE) around the Archean–Proterozoic boundary and theExpand
Protracted oxygenation of the Proterozoic biosphere
Our current understanding of Proterozoic (2.5–0.54 Ga) biospheric evolution highlights the critical role played by the progressive oxygenation of Earth's surface environments and its effect onExpand
Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes
The findings suggest that the Great Oxidation Event did not lead to a unidirectional stepwise increase in atmospheric oxygen, and strong positive fractionations in Cr isotopes in the late Neoproterozoic era provide independent support for increased surface oxygenation at that time, which may have stimulated rapid evolution of macroscopic multicellular life. Expand
Early oxygenation of the terrestrial environment during the Mesoproterozoic
Disproportionation in both red beds and lacustrine black shales at the study site suggests that the Mesoproterozoic terrestrial environment was sufficiently oxygenated to support a biota that was adapted to an oxygen-rich atmosphere, but had also penetrated into subsurface sediment. Expand
Oxygenation of Ediacaran Ocean recorded by iron isotopes
Abstract The increase in atmospheric oxygen during the late Neoproterozoic Era (ca. 800–542 Ma) may have stimulated the oxygenation of the deep oceans and the evolution of macroscopic multicellularExpand
Geobiology of the Proterozoic Eon
The Proterozoic Eon, spanning from 2.5 to 0.54 billion years ago, is Earth’s great middle age – bridging the beginnings of life with the biotic world we see today. Amidst all this change, a longExpand
Hydrogen sulphide release to surface waters at the Precambrian/Cambrian boundary
It is suggested that the Early Cambrian animal radiation may have been triggered by a major change in ocean circulation, terminating a long period during which the Proterozoic ocean was stratified, with sulphidic deep water. Expand


Terminal Proterozoic reorganization of biogeochemical cycles
It is shown that hydrocarbons extracted from Proterozoic sediments in several locations worldwide are derived mainly from bacteria or other heterotrophs rather than from photosyn-thetic organisms, and that preservation of algal-lipid skeletons improves at the beginning of the Cambrian, reflecting the increase in transport by rapidly sinking faecal pellets. Expand
Dynamics of the Neoproterozoic carbon cycle
  • D. Rothman, J. Hayes, R. Summons
  • Environmental Science, Medicine
  • Proceedings of the National Academy of Sciences of the United States of America
  • 2003
It is suggested that the most significant of the Neoproterozoic negative carbon-isotopic excursions resulted from increased remineralization of this reservoir, a process that was likely initiated by evolutionary innovations that increased export of organic matter to the deep sea. Expand
Dating the rise of atmospheric oxygen
It is found that syngenetic pyrite is present in organic-rich shales of the 2.32-Gyr-old Rooihoogte and Timeball Hill formations, South Africa, indicating that atmospheric oxygen was present at significant levels during the deposition of these units. Expand
Low marine sulphate and protracted oxygenation of the Proterozoic biosphere
Large stratigraphic variations in the sulphur isotope composition of marine carbonate-associated sulphate are reported, and a rate-dependent model for sulphor isotope change is used that allows us to track changes in marine sulphate concentrations throughout the Proterozoic. Expand
Carbon isotope evidence for the stepwise oxidation of the Proterozoic environment
Trends in the carbon isotope composition of sedimentary organic carbon and carbonate show that during the Proterozoic aeon the organic carbon reservoir grew in size, relative to the carbonate reservoir, mostly during episodes of global rifting and orogeny. Expand
50 Myr recovery from the largest negative δ13C excursion in the Ediacaran ocean
Sedimentary rocks deposited during the Ediacaran period (∼630–542 Ma) contain carbonates whose carbon isotopic ratios show a marked negative excursion consisting of a precipitous drop from +5‰ toExpand
Sulfur cycling in the aftermath of a 635-Ma snowball glaciation: Evidence for a syn-glacial sulfidic deep ocean
We have analyzed ! 34 S (sulfate and pyrite), ! 18 Ocarbonate and ! 13 Ccarbonate, and major and trace elemental concentrations, including extractable Fe and Mn phases, in four sections of theExpand
The evolution of the Earth surface sulfur reservoir
The surface sulfur reservoir is in intimate contact with the mantle. Over long time scales, exchange with the mantle has influenced the surface reservoir size and possibly its isotopic composition.Expand
Neoproterozoic sulfur isotopes, the evolution of microbial sulfur species, and the burial efficiency of sulfide as sedimentary pyrite
Significant variability in δ34Spyrite values in Neoproterozoic sedimentary rocks has been attributed to the evolution of nonphotosynthetic sulfide-oxidizing bacteria and the advent of sulfurExpand
▪ Abstract This paper reviews the Precambrian history of atmospheric oxygen, beginning with a brief discussion of the possible nature and magnitude of life before the evolution of oxygenicExpand