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Hu F, Jiang H, Wan B, Ducea MN, Gao L, Wu FY. Latitude-dependent oxygen fugacity in arc magmas. Nat Commun 2024; 15:6050. [PMID: 39025886 PMCID: PMC11258285 DOI: 10.1038/s41467-024-50337-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 07/05/2024] [Indexed: 07/20/2024] Open
Abstract
The redox state of arc mantle has been considered to be more oxidized and diverse than that of the mid-ocean ridge, but the cause of the variation is debated. We examine the redox state of the Cenozoic global arc mantle by compiling measured/calculated fO2 of olivine-hosted melt inclusions from arc magma and modeled fO2 based on V/Sc and Cu/Zr ratios of arc basaltic rocks. The results indicate that the redox state of Cenozoic arc mantle is latitude dependent, with less oxidized arc mantle in the low latitudes, contrasting with a near constant across-latitude trend in the mid-ocean ridges. We propose that such a latitude-dependent pattern in the arc mantle may be controlled by the variation in the redox state of subducted sediment, possibly related to a latitudinal variation in the primary production of phytoplankton, which results in more organic carbon and sulfide deposited on the low-latitude ocean floor. Our findings provide evidence for the impact of the surface environment on Earth's upper mantle.
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Affiliation(s)
- Fangyang Hu
- State Key Laboratory of Lithospheric and Environmental Coevolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China.
| | - Hehe Jiang
- State Key Laboratory of Lithospheric and Environmental Coevolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
| | - Bo Wan
- State Key Laboratory of Lithospheric and Environmental Coevolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
| | - Mihai N Ducea
- Faculty of Geology and Geophysics, University of Bucharest, Bucharest, Romania
- Department of Geosciences, University of Arizona, Tucson, AZ, USA
| | - Lei Gao
- State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Sciences and Resources, China University of Geosciences, Beijing, China
| | - Fu-Yuan Wu
- State Key Laboratory of Lithospheric and Environmental Coevolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China
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2
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Birner SK, Cottrell E, Davis FA, Warren JM. Deep, hot, ancient melting recorded by ultralow oxygen fugacity in peridotites. Nature 2024; 631:801-807. [PMID: 39048684 DOI: 10.1038/s41586-024-07603-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 05/23/2024] [Indexed: 07/27/2024]
Abstract
The oxygen fugacity (fO2) of convecting upper mantle recorded by ridge peridotites varies by more than four orders of magnitude1-3. Although much attention has been given to mechanisms that drive variations in mantle fO2 between tectonic settings1,3,4 and to comparisons of fO2 between modern rocks and ancient-mantle-derived rocks5-10, comparatively little has been done to understand the origins of the high variability in fO2 recorded by peridotites from modern mid-ocean ridge settings. Here we report the petrography and geochemistry of peridotites from the Gakkel Ridge and East Pacific Rise (EPR), including 16 new high-precision determinations of fO2. Refractory peridotites from the Gakkel Ridge record fO2 more than four orders of magnitude below the mantle average. With thermodynamic and mineral partitioning modelling, we show that excursions to ultralow fO2 can be produced by large degrees of melting at high potential temperature (Tp), beginning in the garnet field and continuing into the spinel field-conditions met during the generation of ancient komatiites but not modern basalts. This does not mean that ambient convecting upper mantle had a lower ferric to ferrous ratio in Archaean times than today nor that modern melting in the garnet field at hotspots produce reduced magmas. Instead, it implies that rafts of ancient, refractory, ultrareduced mantle continue to circulate in the modern mantle while contributing little to modern ridge volcanism.
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Affiliation(s)
- Suzanne K Birner
- Division of Natural Sciences, Nursing, and Mathematics, Berea College, Berea, KY, USA.
| | - Elizabeth Cottrell
- National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
| | - Fred A Davis
- Department of Earth and Environmental Sciences, University of Minnesota Duluth, Duluth, MN, USA
| | - Jessica M Warren
- Department of Earth Sciences, University of Delaware, Newark, DE, USA
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3
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Sahoo SK, Gilleaudeau GJ, Wilson K, Hart B, Barnes BD, Faison T, Bowman AR, Larson TE, Kaufman AJ. Basin-scale reconstruction of euxinia and Late Devonian mass extinctions. Nature 2023; 615:640-645. [PMID: 36890233 DOI: 10.1038/s41586-023-05716-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 01/09/2023] [Indexed: 03/10/2023]
Abstract
The Devonian-Carboniferous transition marks a fundamental shift in the surface environment primarily related to changes in ocean-atmosphere oxidation states1,2, resulting from the continued proliferation of vascular land plants that stimulated the hydrological cycle and continental weathering3,4, glacioeustasy5,6, eutrophication and anoxic expansion in epicontinental seas3,4, and mass extinction events2,7,8. Here we present a comprehensive spatial and temporal compilation of geochemical data from 90 cores across the entire Bakken Shale (Williston Basin, North America). Our dataset allows for the detailed documentation of stepwise transgressions of toxic euxinic waters into the shallow oceans that drove a series of Late Devonian extinction events. Other Phanerozoic extinctions have also been related to the expansion of shallow-water euxinia, indicating that hydrogen sulfide toxicity was a key driver of Phanerozoic biodiversity.
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Affiliation(s)
| | | | | | - Bruce Hart
- Equinor US, Houston, TX, USA
- University of Western Ontario, London, Ontario, Canada
| | - Ben D Barnes
- Pennsylvania State University, University Park, PA, USA
| | | | | | - Toti E Larson
- Bureau of Economic Geology, University of Texas at Austin, Austin, TX, USA
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4
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Gao L, Liu S, Cawood PA, Hu F, Wang J, Sun G, Hu Y. Oxidation of Archean upper mantle caused by crustal recycling. Nat Commun 2022; 13:3283. [PMID: 35672309 PMCID: PMC9174474 DOI: 10.1038/s41467-022-30886-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 05/13/2022] [Indexed: 11/23/2022] Open
Abstract
The redox evolution of Archean upper mantle impacted mantle melting and the nature of chemical equilibrium between mantle, ocean and atmosphere of the early Earth. Yet, the origin of these variations in redox remain controversial. Here we show that a global compilation of ∼3.8-2.5 Ga basalts can be subdivided into group B-1, showing modern mid-ocean ridge basalt-like features ((Nb/La)PM ≥ 0.75), and B-2, which are similar to contemporary island arc-related basalts ((Nb/La)PM < 0.75). Our V-Ti redox proxy indicates a more reducing upper mantle, and the results of both ambient and modified mantle obtained from B-1 and B-2 samples, respectively, exhibit a ∼1.0 log unit increase in their temporal evolution for most cratons. Increases in mantle oxygen fugacity are coincident with the changes in basalt Th/Nb ratios and Nd isotope ratios, indicating that crustal recycling played a crucial role, and this likely occurred either via plate subduction or lithospheric drips. The basalt V-Ti redox proxy indicates that both of the Archean ambient and modified mantle exhibit a ~1.0 log unit increase in their evolution for most cratons, possibly derived by widespread crustal recycling.
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5
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Kerou M, Ponce-Toledo RI, Zhao R, Abby SS, Hirai M, Nomaki H, Takaki Y, Nunoura T, Jørgensen SL, Schleper C. Genomes of Thaumarchaeota from deep sea sediments reveal specific adaptations of three independently evolved lineages. THE ISME JOURNAL 2021; 15:2792-2808. [PMID: 33795828 PMCID: PMC8397731 DOI: 10.1038/s41396-021-00962-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 01/12/2021] [Accepted: 03/11/2021] [Indexed: 02/01/2023]
Abstract
Marine sediments represent a vast habitat for complex microbiomes. Among these, ammonia oxidizing archaea (AOA) of the phylum Thaumarchaeota are one of the most common, yet little explored, inhabitants, which seem extraordinarily well adapted to the harsh conditions of the subsurface biosphere. We present 11 metagenome-assembled genomes of the most abundant AOA clades from sediment cores obtained from the Atlantic Mid-Ocean ridge flanks and Pacific abyssal plains. Their phylogenomic placement reveals three independently evolved clades within the order Nitrosopumilales, of which no cultured representative is known yet. In addition to the gene sets for ammonia oxidation and carbon fixation known from other AOA, all genomes encode an extended capacity for the conversion of fermentation products that can be channeled into the central carbon metabolism, as well as uptake of amino acids probably for protein maintenance or as an ammonia source. Two lineages encode an additional (V-type) ATPase and a large repertoire of DNA repair systems that may allow to overcome the challenges of high hydrostatic pressure. We suggest that the adaptive radiation of AOA into marine sediments occurred more than once in evolution and resulted in three distinct lineages with particular adaptations to this extremely energy-limiting and high-pressure environment.
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Affiliation(s)
- Melina Kerou
- grid.10420.370000 0001 2286 1424Department of Functional and Evolutionary Ecology, Archaea Biology and Ecogenomics Unit, University of Vienna, Vienna, Austria
| | - Rafael I. Ponce-Toledo
- grid.10420.370000 0001 2286 1424Department of Functional and Evolutionary Ecology, Archaea Biology and Ecogenomics Unit, University of Vienna, Vienna, Austria
| | - Rui Zhao
- grid.7914.b0000 0004 1936 7443Department of Earth Science, K.G. Jebsen Centre for Deep Sea Research, University of Bergen, Bergen, Norway ,grid.33489.350000 0001 0454 4791Present Address: School of Marine Science and Policy, University of Delaware, Lewes, DE USA
| | - Sophie S. Abby
- grid.10420.370000 0001 2286 1424Department of Functional and Evolutionary Ecology, Archaea Biology and Ecogenomics Unit, University of Vienna, Vienna, Austria ,grid.463716.10000 0004 4687 1979Present Address: University Grenoble Alpes, CNRS, Grenoble INP, TIMC-IMAG, Grenoble, France
| | - Miho Hirai
- grid.410588.00000 0001 2191 0132Super-cutting-edge Grand and Advanced Research (SUGAR) Program, X-star, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
| | - Hidetaka Nomaki
- grid.410588.00000 0001 2191 0132Super-cutting-edge Grand and Advanced Research (SUGAR) Program, X-star, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
| | - Yoshihiro Takaki
- grid.410588.00000 0001 2191 0132Super-cutting-edge Grand and Advanced Research (SUGAR) Program, X-star, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
| | - Takuro Nunoura
- grid.410588.00000 0001 2191 0132Research Center for Bioscience and Nanoscience (CeBN), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
| | - Steffen L. Jørgensen
- grid.7914.b0000 0004 1936 7443Department of Earth Science, K.G. Jebsen Centre for Deep Sea Research, University of Bergen, Bergen, Norway
| | - Christa Schleper
- grid.10420.370000 0001 2286 1424Department of Functional and Evolutionary Ecology, Archaea Biology and Ecogenomics Unit, University of Vienna, Vienna, Austria
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6
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Meng X, Kleinsasser JM, Richards JP, Tapster SR, Jugo PJ, Simon AC, Kontak DJ, Robb L, Bybee GM, Marsh JH, Stern RA. Oxidized sulfur-rich arc magmas formed porphyry Cu deposits by 1.88 Ga. Nat Commun 2021; 12:2189. [PMID: 33850122 PMCID: PMC8044198 DOI: 10.1038/s41467-021-22349-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 03/03/2021] [Indexed: 11/18/2022] Open
Abstract
Most known porphyry Cu deposits formed in the Phanerozoic and are exclusively associated with moderately oxidized, sulfur-rich, hydrous arc-related magmas derived from partial melting of the asthenospheric mantle metasomatized by slab-derived fluids. Yet, whether similar metallogenic processes also operated in the Precambrian remains obscure. Here we address the issue by investigating the origin, fO2, and S contents of calc-alkaline plutonic rocks associated with the Haib porphyry Cu deposit in the Paleoproterozoic Richtersveld Magmatic Arc (southern Namibia), an interpreted mature island-arc setting. We show that the ca. 1886–1881 Ma ore-forming magmas, originated from a mantle-dominated source with minor crustal contributions, were relatively oxidized (1‒2 log units above the fayalite-magnetite-quartz redox buffer) and sulfur-rich. These results indicate that moderately oxidized, sulfur-rich arc magma associated with porphyry Cu mineralization already existed in the late Paleoproterozoic, probably as a result of recycling of sulfate-rich seawater or sediments from the subducted oceanic lithosphere at that time. Tectonomagmatic conditions in the Precambrian were hypothesized to be unfavorable for porphyry Cu deposit formation. Here, the authors show that metallogenic processes typify Phanerozoic porphyry Cu deposits operated by ~1.88 Ga, reflecting modification of mantle lithosphere by oxidized slab-derived fluids at that time.
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Affiliation(s)
- Xuyang Meng
- Mineral Exploration Research Centre, Harquail School of Earth Sciences, Laurentian University, Sudbury, ON, Canada.
| | - Jackie M Kleinsasser
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Jeremy P Richards
- Mineral Exploration Research Centre, Harquail School of Earth Sciences, Laurentian University, Sudbury, ON, Canada
| | - Simon R Tapster
- Geochronology and Tracers Facility, British Geological Survey, Nottingham, UK
| | - Pedro J Jugo
- Mineral Exploration Research Centre, Harquail School of Earth Sciences, Laurentian University, Sudbury, ON, Canada
| | - Adam C Simon
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA
| | - Daniel J Kontak
- Mineral Exploration Research Centre, Harquail School of Earth Sciences, Laurentian University, Sudbury, ON, Canada
| | - Laurence Robb
- Department of Earth Sciences, University of Oxford, Oxford, UK.,DSI-NRF Centre of Excellence, University of Johannesburg, Johannesburg, South Africa
| | - Grant M Bybee
- School of Geosciences, University of Witwatersrand, Johannesburg, South Africa
| | - Jeffrey H Marsh
- Mineral Exploration Research Centre, Harquail School of Earth Sciences, Laurentian University, Sudbury, ON, Canada
| | - Richard A Stern
- Canadian Centre for Isotopic Microanalysis, University of Alberta, Edmonton, AB, Canada
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7
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Ward LM, Johnston DT, Shih PM. Phanerozoic radiation of ammonia oxidizing bacteria. Sci Rep 2021; 11:2070. [PMID: 33483596 PMCID: PMC7822890 DOI: 10.1038/s41598-021-81718-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 01/11/2021] [Indexed: 01/30/2023] Open
Abstract
The modern nitrogen cycle consists of a web of microbially mediated redox transformations. Among the most crucial reactions in this cycle is the oxidation of ammonia to nitrite, an obligately aerobic process performed by a limited number of lineages of bacteria (AOB) and archaea (AOA). As this process has an absolute requirement for O2, the timing of its evolution-especially as it relates to the Great Oxygenation Event ~ 2.3 billion years ago-remains contested and is pivotal to our understanding of nutrient cycles. To estimate the antiquity of bacterial ammonia oxidation, we performed phylogenetic and molecular clock analyses of AOB. Surprisingly, bacterial ammonia oxidation appears quite young, with crown group clades having originated during Neoproterozoic time (or later) with major radiations occurring during Paleozoic time. These results place the evolution of AOB broadly coincident with the pervasive oxygenation of the deep ocean. The late evolution AOB challenges earlier interpretations of the ancient nitrogen isotope record, predicts a more substantial role for AOA during Precambrian time, and may have implications for understanding of the size and structure of the biogeochemical nitrogen cycle through geologic time.
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Affiliation(s)
- L M Ward
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA.
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan.
| | - D T Johnston
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA, USA
| | - P M Shih
- Department of Plant Biology, University of California, Davis, Davis, CA, USA
- Department of Energy, Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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8
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Li C, Shi W, Cheng M, Jin C, Algeo TJ. The redox structure of Ediacaran and early Cambrian oceans and its controls. Sci Bull (Beijing) 2020; 65:2141-2149. [PMID: 36732967 DOI: 10.1016/j.scib.2020.09.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 02/04/2023]
Abstract
The rapid diversification of early animals during the Ediacaran (635-541 Ma) and early Cambrian (ca. 541-509 Ma) has frequently been attributed to increasing oceanic oxygenation. However, the pattern of oceanic oxygenation and its relationship to early animal evolution remain in debate. In this review, we examine the redox structure of Ediacaran and early Cambrian oceans and its controls, offering new insights into contemporaneous oceanic oxygenation patterns and their role in the coevolution of environments and early animals. We review the development of marine redox models which, in combination with independent distal deep-ocean redox proxies, supports a highly redox-stratified shelf and an anoxia-dominated deep ocean during the Ediacaran and early Cambrian. Geochemical and modeling evidence indicates that the marine redox structure was likely controlled by low atmospheric O2 levels and low seawater vertical mixing rates on shelves at that time. Furthermore, theoretical analysis and increasing geochemical evidence, particularly from South China, show that limited sulfate availability was a primary control on the attenuation of mid-depth euxinia offshore, in contrast to the existing paradigm invoking decreased organic carbon fluxes distally. In light of our review, we infer that if oceanic oxygenation indeed triggered the rise of early animals, it must have done so through a shelf oxygenation which was probably driven by elevated oxidant availability. Our review calls for further studies on Ediacaran-Cambrian marine redox structure and its controls, particularly from regions outside of South China, in order to better understand the coevolutionary relationship between oceanic redox and early animals.
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Affiliation(s)
- Chao Li
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China.
| | - Wei Shi
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| | - Meng Cheng
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
| | - Chengsheng Jin
- Yunnan Key Laboratory for Palaeobiology, Yunnan University, Kunming 650091, China
| | - Thomas J Algeo
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China; State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences, Wuhan 430074, China; Department of Geology, University of Cincinnati, Cincinnati OH45221, USA
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9
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Yierpan A, König S, Labidi J, Schoenberg R. Recycled selenium in hot spot-influenced lavas records ocean-atmosphere oxygenation. SCIENCE ADVANCES 2020; 6:6/39/eabb6179. [PMID: 32967831 PMCID: PMC7531878 DOI: 10.1126/sciadv.abb6179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 08/03/2020] [Indexed: 05/23/2023]
Abstract
Oxygenation of Earth's oceans and atmosphere through time has consequences for subducted surface signatures that are now stored in the mantle. Here, we report significant mass-dependent selenium isotope variations in modern hot spot-influenced oceanic lavas. These variations are correlated with tracers of mantle source enrichment, which can only be explained by incorporation of abyssal pelagic sediments subducted from a redox-stratified mid-Proterozoic ocean. Selenium geochemical signatures of these sediments have mostly been preserved during long-term recycling and may therefore complement the global surface sediment record as ancient oxygen archives. Combined deep mantle and surface perspectives, together with emerging models for atmospheric oxygen based on selenium systematics, further imply a significantly oxygenated ocean-atmosphere system throughout the mid-Proterozoic.
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Affiliation(s)
- Aierken Yierpan
- Isotope Geochemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, Germany.
| | - Stephan König
- Isotope Geochemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, Germany.
| | - Jabrane Labidi
- Isotope Geochemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, Germany
- Institut de Physique du Globe de Paris, 1 rue Jussieu, 75005 Paris, France
| | - Ronny Schoenberg
- Isotope Geochemistry, Department of Geosciences, University of Tübingen, 72076 Tübingen, Germany
- Department of Geology, University of Johannesburg, 2092 Johannesburg, South Africa
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10
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Tang M, Lee CTA, Ji WQ, Wang R, Costin G. Crustal thickening and endogenic oxidation of magmatic sulfur. SCIENCE ADVANCES 2020; 6:eaba6342. [PMID: 32832683 PMCID: PMC7439493 DOI: 10.1126/sciadv.aba6342] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
Porphyry ore deposits, Earth's most important resources of copper, molybdenum, and rhenium, are strongly associated with felsic magmas showing signs of high-pressure differentiation and are usually found in places with thickened crust (>45 kilometers). This pattern is well-known, but unexplained, and remains an outstanding problem in our understanding of porphyry ore deposit formation. We approach this problem by investigating the oxidation state of magmatic sulfur, which controls the behavior of ore-forming metals during magma differentiation and magmatic-hydrothermal transition. We use sulfur in apatite to reconstruct the sulfur oxidation state in the Gangdese batholith, southern Tibet. We find that magma sulfate content increased abruptly after India-Eurasia collision. Apatite sulfur content and the calculated magma S6+/ΣS ratio correlate with whole-rock dysprosium/ytterbium ratio, suggesting that residual garnet, favored in thickened crust, exerts a first-order control on sulfur oxidation in magmatic orogens. Our findings link sulfur oxidation to internal petrogenic processes and imply an intrinsic relationship of magma oxidation with synmagmatic crustal thickening.
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Affiliation(s)
- Ming Tang
- School of Earth and Space Sciences, Peking University, Beijing 100871, China
- Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX 77005, USA
| | - Cin-Ty A. Lee
- Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX 77005, USA
| | - Wei-Qiang Ji
- State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, P.O. Box 9825, Beijing 100029, China
| | - Rui Wang
- State Key Laboratory of Geological Processes and Mineral Resources, and Institute of Earth Sciences, China University of Geosciences, Beijing 100083, China
| | - Gelu Costin
- Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX 77005, USA
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11
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Braakman R. Evolution of cellular metabolism and the rise of a globally productive biosphere. Free Radic Biol Med 2019; 140:172-187. [PMID: 31082508 DOI: 10.1016/j.freeradbiomed.2019.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 02/28/2019] [Accepted: 05/02/2019] [Indexed: 01/14/2023]
Abstract
Metabolic processes in cells and chemical processes in the environment are fundamentally intertwined and have evolved in concert for most of Earth's existence. Here I argue that intrinsic properties of cellular metabolism imposed central constraints on the historical trajectories of biopsheric productivity and atmospheric oxygenation. Photosynthesis depends on iron, but iron is highly insoluble under the aerobic conditions produced by oxygenic photosynthesis. These counteracting constraints led to two major stages of Earth oxygenation. After a cyanobacteria-driven biospheric expansion near the Archean-Proterozoic boundary, productivity remained largely restricted to continental boundaries and shallow aquatic environments where weathering inputs made iron more accessible. The anoxic deep open ocean was rich in free iron during the Proterozoic, but this iron was largely inaccessible, partly because an otherwise nutrient-poor ocean was limiting to photosynthesis, but also because a photosynthetic expansion would have quenched its own iron supply. Near the Proterozoic-Phanerozoic boundary, bioenergetics innovations allowed eukaryotic photosynthesis to overcome these interconnected negative feedbacks and begin expanding into the deep open oceans and onto the continents, where nutrients are inherently harder to come by. Key insights into what drove the ecological rise of eukaryotic photosynthesis emerge from analyses of marine Synechococcus and Prochlorococcus, abundant marine picocyanobacteria whose ancestors colonized the oceans in the Neoproterozoic. The reconstructed evolution of this group reveals a sequence of innovations that ultimately produced a form of photosynthesis in Prochlorococcus that is more like that of green plant cells than other cyanobacteria. Innovations increased the energy flux of cells, thereby enhancing their ability to acquire sparse nutrients, and as by-product also increased the production of organic carbon waste. Some of these organic waste products had the ability to chelate iron and make it bioavailable, thereby indirectly pushing the oceans through a transition from an anoxic state rich in free iron to an oxygenated state with organic carbon-bound iron. Resulting conditions (and parallel processes on the continents) in turn led to a series of positive feedbacks that increased the availability of other nutrients, thereby promoting the rise of a globally productive biosphere. In addition to the occurrence of major biospheric expansions, the several hundred million-year periods around the Archean-Proterozoic and Proterozoic-Phanerozoic boundaries share a number of other parallels. Both epochs have also been linked to major carbon cycle perturbations and global glaciations, as well as changes in the nature of plate tectonics and increases in continental exposure and weathering. This suggests the dynamics of life and Earth are intimately intertwined across many levels and that general principles governed transitions in these coupled dynamics at both times in Earth history.
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Affiliation(s)
- Rogier Braakman
- Department of Civil & Environmental Engineering, Massachusetts Institute of Technology, USA; Department of Earth, Atmospheric & Planetary Sciences, Massachusetts Institute of Technology, USA.
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