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Jalowitzki T, Sumino H, Conceição RV, Schilling ME, Bertotto GW, Tassara A, Gervasoni F, Orihashi Y, Nagao K, Rocha MP, Rodrigues RADF. Pristine helium from the Karoo mantle plume within the shallow asthenosphere beneath Patagonia. Nat Commun 2024; 15:6402. [PMID: 39080268 PMCID: PMC11289271 DOI: 10.1038/s41467-024-50773-4] [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: 07/19/2022] [Accepted: 07/19/2024] [Indexed: 08/02/2024] Open
Abstract
Mantle xenoliths usually represent fragments derived from the depleted and degassed lithospheric mantle with 3He/4He isotope ratios (6 ± 1 RA) lower than those of mid-ocean ridge basalts (8 ± 1 RA). Otherwise, basalts from oceanic islands related to hotspots often have high 3He/4He ratios (>10 RA), suggesting a deep and pristine undegassed mantle source. Here we present a striking high-3He/4He component (up to 27.68 RA) recorded by spinel-facies mantle xenoliths from Patagonia. Remarkably, the highest ratios were found in a long-lived trans-lithospheric suture zone related to the Carboniferous-Permian collision of two continental blocks: the Deseado and the North Patagonian massifs. The mantle xenoliths with notably high-3He/4He ratios are inferred to be fragments of the shallow asthenosphere rising through the eroded and rejuvenated thin lithosphere. The pristine helium component is derived from the western margin of the Karoo mantle plume, related to the initial stages of the Gondwana fragmentation.
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Affiliation(s)
- Tiago Jalowitzki
- Programa de Pós-graduação em Geologia, Instituto de Geociências, Universidade de Brasília (UnB), Brasília, Brazil.
| | - Hirochika Sumino
- Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan
| | - Rommulo V Conceição
- Programa de Pós-graduação em Geociências, Instituto de Geociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Manuel E Schilling
- Instituto de Ciencias de la Tierra, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Gustavo W Bertotto
- INCITAP, CONICET - Universidad Nacional de La Pampa, Santa Rosa, Argentina
| | - Andrés Tassara
- Departamento de Ciencias de la Tierra, Universidad de Concepción, Concepción, Chile
| | - Fernanda Gervasoni
- Programa de Pós-graduação em Geociências, Instituto de Geociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Centro de Engenharias, Universidade Federal de Pelotas (UFPel), Pelotas, Brazil
| | - Yuji Orihashi
- Department of Earth and Environmental Sciences, Hirosaki University, Hirosaki, Japan
| | - Keisuke Nagao
- Division of Polar Earth-System Sciences, KOPRI (Korea Polar Research Institute), Yeonsu-gu, South Korea
| | - Marcelo Peres Rocha
- Programa de Pós-graduação em Geologia, Instituto de Geociências, Universidade de Brasília (UnB), Brasília, Brazil
| | - Rodrigo Antonio de Freitas Rodrigues
- Programa de Pós-graduação em Geologia, Instituto de Geociências, Universidade de Brasília (UnB), Brasília, Brazil
- Research School of Earth Science, Australian National University, Canberra, ACT, 0200, Australia
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2
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Zhang M, Xu S, Sano Y. Deep carbon recycling viewed from global plate tectonics. Natl Sci Rev 2024; 11:nwae089. [PMID: 38933601 PMCID: PMC11203916 DOI: 10.1093/nsr/nwae089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 03/01/2024] [Accepted: 03/05/2024] [Indexed: 06/28/2024] Open
Abstract
Plate tectonics plays an essential role in the redistribution of life-essential volatile elements between Earth's interior and surface, whereby our planet has been well tuned to maintain enduring habitability over much of its history. Here we present an overview of deep carbon recycling in the regime of modern plate tectonics, with a special focus on convergent plate margins for assessing global carbon mass balance. The up-to-date flux compilation implies an approximate balance between deep carbon outflux and subduction carbon influx within uncertainty but remarkably limited return of carbon to convecting mantle. If correct, carbon would gradually accumulate in the lithosphere over time by (i) massive subsurface carbon storage occurring primarily in continental lithosphere from convergent margins to continental interior and (ii) persistent surface carbon sinks to seafloors sustained by high-flux deep CO2 emissions to the atmosphere. Further assessment of global carbon mass balance requires updates on fluxes of subduction-driven carbon recycling paths and reduction in uncertainty of deep carbon outflux. From a global plate tectonics point of view, we particularly emphasize that continental reworking is an important mechanism for remobilizing geologically sequestered carbon in continental crust and sub-continental lithospheric mantle. In light of recent advances, future research is suggested to focus on a better understanding of the reservoirs, fluxes, mechanisms, and climatic effects of deep carbon recycling following an integrated methodology of observation, experiment, and numerical modeling, with the aim of decoding the self-regulating Earth system and its habitability from the deep carbon recycling perspective.
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Affiliation(s)
- Maoliang Zhang
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Sheng Xu
- School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Yuji Sano
- Marine Core Research Institute, Kochi University, Kochi 783-8502, Japan
- Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba 277-8564, Japan
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3
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Bao X. Giant impact and Earth's mysterious blobs: An interdisciplinary revelation. Sci Bull (Beijing) 2024; 69:293-294. [PMID: 38123432 DOI: 10.1016/j.scib.2023.12.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Affiliation(s)
- Xiyuan Bao
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles CA 90095, USA.
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4
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Horton F, Asimow PD, Farley KA, Curtice J, Kurz MD, Blusztajn J, Biasi JA, Boyes XM. Highest terrestrial 3He/ 4He credibly from the core. Nature 2023; 623:90-94. [PMID: 37853120 DOI: 10.1038/s41586-023-06590-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 08/30/2023] [Indexed: 10/20/2023]
Abstract
The observation that many lavas associated with mantle plumes have higher 3He/4He ratios than the upper convecting mantle underpins geophysical, geodynamic and geochemical models of Earth's deep interior. High 3He/4He ratios are thought to derive from the solar nebula or from solar-wind-irradiated material that became incorporated into Earth during early planetary accretion. Traditionally, this high-3He/4He component has been considered intrinsic to the mantle, having avoided outgassing caused by giant impacts and billions of years of mantle convection1-4. Here we report the highest magmatic 3He/4He ratio(67.2 ± 1.8 times the atmospheric ratio) yet measured in terrestrial igneous rocks, in olivines from Baffin Island lavas. We argue that the extremely high-3He/4He helium in these lavas might derive from Earth's core5-9. The viability of the core hypothesis relaxes the long-standing constraint-based on noble gases in lavas associated with mantle plumes globally-that volatile elements from the solar nebula have survived in the mantle since the early stages of accretion.
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Affiliation(s)
- F Horton
- Geology and Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA.
| | - P D Asimow
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - K A Farley
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - J Curtice
- Geology and Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - M D Kurz
- Geology and Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - J Blusztajn
- Geology and Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - J A Biasi
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
- Department of Earth Sciences, Dartmouth College, Hanover, NH, USA
| | - X M Boyes
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
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5
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Mather BR, Müller RD, Alfonso CP, Seton M, Wright NM. Kimberlite eruptions driven by slab flux and subduction angle. Sci Rep 2023; 13:9216. [PMID: 37280326 DOI: 10.1038/s41598-023-36250-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 05/30/2023] [Indexed: 06/08/2023] Open
Abstract
Kimberlites are sourced from thermochemical upwellings which can transport diamonds to the surface of the crust. The majority of kimberlites preserved at the Earth's surface erupted between 250 and 50 million years ago, and have been attributed to changes in plate velocity or mantle plumes. However, these mechanisms fail to explain the presence of strong subduction signatures observed in some Cretaceous kimberlites. This raises the question whether there is a subduction process that unifies our understanding of the timing of kimberlite eruptions. We develop a novel formulation for calculating subduction angle based on trench migration, convergence rate, slab thickness and density to connect the influx of slab material into the mantle with the timing of kimberlite eruptions. We find that subduction angles combined with peaks in slab flux predict pulses of kimberlite eruptions. High rates of subducting slab material trigger mantle return flow that stimulates fertile reservoirs in the mantle. These convective instabilities transport slab-influenced melt to the surface at a distance inbound from the trench corresponding to the subduction angle. Our deep-time slab dip formulation has numerous potential applications including modelling the deep carbon and water cycles, and an improved understanding of subduction-related mineral deposits.
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Affiliation(s)
- Ben R Mather
- EarthByte Group, School of Geosciences, The University of Sydney, Sydney, 2006, Australia.
| | - R Dietmar Müller
- EarthByte Group, School of Geosciences, The University of Sydney, Sydney, 2006, Australia
| | - Christopher P Alfonso
- EarthByte Group, School of Geosciences, The University of Sydney, Sydney, 2006, Australia
| | - Maria Seton
- EarthByte Group, School of Geosciences, The University of Sydney, Sydney, 2006, Australia
| | - Nicky M Wright
- EarthByte Group, School of Geosciences, The University of Sydney, Sydney, 2006, Australia
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6
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Soderman CR, Shorttle O, Gazel E, Geist DJ, Matthews S, Williams HM. The evolution of the Galápagos mantle plume. SCIENCE ADVANCES 2023; 9:eadd5030. [PMID: 36897953 PMCID: PMC10005182 DOI: 10.1126/sciadv.add5030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
The lavas associated with mantle plumes may sample domains throughout Earth's mantle and probe its dynamics. However, plume studies are often only able to take snapshots in time, usually of the most recent plume activity, leaving the chemical and geodynamic evolution of major convective upwellings in Earth's mantle poorly constrained. Here, we report the geodynamically key information of how the lithology and density of a plume change from plume head phase to tail. We use iron stable isotopes and thermodynamic modeling to show that the Galápagos plume has contained small, nearly constant, amounts of dense recycled crust over its 90-million-year history. Despite a temporal evolution in the amount of recycled crust-derived melt in Galápagos-related lavas, we show that this can be explained by plume cooling alone, without associated changes in the plume's mantle source; results are also consistent with a plume rooted in a lower mantle low-velocity zone also sampling primordial components.
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Affiliation(s)
| | - Oliver Shorttle
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
- Institute of Astronomy, University of Cambridge, Cambridge, UK
| | - Esteban Gazel
- Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY, USA
| | - Dennis J. Geist
- Department of Geological Sciences, University of Idaho, Moscow, ID, USA
| | - Simon Matthews
- Institute of Earth Sciences, University of Iceland, Reykjavík, Iceland
| | - Helen M. Williams
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
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7
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Jiao Y, Liu M, Wu Q, Zheng P, Xu W, Ye B, Zhang H, Guo R, Luo S. Finely tuning the microporosity in phosphoric acid doped triptycene-containing polybenzimidazole membranes for highly permselective helium and hydrogen recovery. J Memb Sci 2023. [DOI: 10.1016/j.memsci.2023.121474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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8
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Zinc isotopic evidence for recycled carbonate in the deep mantle. Nat Commun 2022; 13:6085. [PMID: 36241628 PMCID: PMC9568527 DOI: 10.1038/s41467-022-33789-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 09/22/2022] [Indexed: 11/25/2022] Open
Abstract
Carbonate, the major carbon reservoir on Earth’s surface, can enter into the mantle by subduction. However, evidence for recycled surficial carbonates in the deep mantle is still scarce. Ocean island basalts from Cook-Austral islands and St. Helena Island, widely called HIMU basalts because of their high μ = 238U/204Pb sources, are thought to be fed by mantle plumes originating in the lower mantle. Here we report exceptionally high δ66Zn values (δ66Zn = 0.38 ± 0.03‰) of these HIMU lavas relative to most published data for oceanic basalts (δ66Zn = 0.31 ± 0.10‰), which requires a source contributed by isotopically heavy recycled surficial carbonates. During subduction of the oceanic lithosphere, melting of mixed surficial carbonates and basaltic crust in the deep mantle generates carbonatite melts, which metasomatizes the nearby mantle and the resultant carbonated mantle ultimately evolves into a high-δ66Zn HIMU source. High-δ66Zn signatures of HIMU basalts, therefore, demonstrate that carbonates can be transported into Earth’s deep mantle. Zhang et al. perform high-precision zinc (Zn) isotopic analysis on lavas from St. Helena Island in the Atlantic, and Cook-Austral Islands in the Pacific, and confirm that ancient superficial carbonates were transported into the deep mantle billions of years ago.
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9
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Bao X, Lithgow-Bertelloni CR, Jackson MG, Romanowicz B. On the relative temperatures of Earth's volcanic hotspots and mid-ocean ridges. Science 2022; 375:57-61. [PMID: 34990241 DOI: 10.1126/science.abj8944] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Volcanic hotspots are thought to be fed by hot, active upwellings from the deep mantle, with excess temperatures (Tex) ~100° to 300°C higher than those of mid-ocean ridges. However, Tex estimates are limited in geographical coverage and often inconsistent for individual hotspots. We infer the temperature of oceanic hotspots and ridges simultaneously by converting seismic velocity to temperature. We show that while ~45% of plume-fed hotspots are hot (Tex ≥ 155°C), ~15% are cold (Tex ≤ 36°C) and ~40% are not hot enough to actively upwell (50°C ≤ Tex ≤ 136°C). Hot hotspots have an extremely high helium-3/helium-4 ratio and buoyancy flux, but cold hotspots do not. The latter may originate at upper mantle depths. Alternatively, the deep plumes that feed them may be entrained and cooled by small-scale convection.
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Affiliation(s)
- Xiyuan Bao
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | | | - Matthew G Jackson
- Department of Earth Science, University of California, Santa Barbara, CA 93106, USA
| | - Barbara Romanowicz
- Department of Earth and Planetary Science, University of California, Berkeley, CA 94720, USA
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10
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Zhang J, Liu H, Ma Y, Chen C. Direct H-He chemical association in superionic FeO2H2He at Deep-Earth conditions. Natl Sci Rev 2021; 9:nwab168. [PMID: 35928982 PMCID: PMC9344844 DOI: 10.1093/nsr/nwab168] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 11/13/2022] Open
Abstract
Hydrogen and helium are known to play crucial roles in geological and astrophysical environments; however, they are inert toward each other across wide pressure-temperature (P-T) conditions. Given their prominent presence and influence on the formation and evolution of celestial bodies, it is of fundamental interest to explore the nature of interactions between hydrogen and helium. Using an advanced crystal structure search method, we have identified a quaternary compound FeO2H2He stabilized in a wide range of P-T conditions. Ab initio molecular dynamics simulations further reveal a novel superionic state of FeO2H2He hosting liquid-like diffusive hydrogen in the FeO2He sublattice, creating a conducive environment for H-He chemical association, at P-T conditions corresponding to the Earth's lowest mantle regions. To our surprise, this chemically facilitated coalescence of otherwise immiscible molecular species highlights a promising avenue for exploring this long-sought but hitherto unattainable state of matter. This finding raises strong prospects for exotic H-He mixtures inside Earth and possibly also in other astronomical bodies.
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Affiliation(s)
- Jurong Zhang
- International Center for Computational Method and Software & State Key Laboratory of Superhard Materials & Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, China
- Shandong Provincial Engineering and Technical Center of Light Manipulations & Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China
| | - Hanyu Liu
- International Center for Computational Method and Software & State Key Laboratory of Superhard Materials & Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, China
- International Center of Future Science, Jilin University, Changchun 130012, China
| | - Yanming Ma
- International Center for Computational Method and Software & State Key Laboratory of Superhard Materials & Key Laboratory of Physics and Technology for Advanced Batteries (Ministry of Education), College of Physics, Jilin University, Changchun 130012, China
- International Center of Future Science, Jilin University, Changchun 130012, China
| | - Changfeng Chen
- Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154, USA
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11
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Ancient helium and tungsten isotopic signatures preserved in mantle domains least modified by crustal recycling. Proc Natl Acad Sci U S A 2020; 117:30993-31001. [PMID: 33229590 DOI: 10.1073/pnas.2009663117] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Rare high-3He/4He signatures in ocean island basalts (OIB) erupted at volcanic hotspots derive from deep-seated domains preserved in Earth's interior. Only high-3He/4He OIB exhibit anomalous 182W-an isotopic signature inherited during the earliest history of Earth-supporting an ancient origin of high 3He/4He. However, it is not understood why some OIB host anomalous 182W while others do not. We provide geochemical data for the highest-3He/4He lavas from Iceland (up to 42.9 times atmospheric) with anomalous 182W and examine how Sr-Nd-Hf-Pb isotopic variations-useful for tracing subducted, recycled crust-relate to high 3He/4He and anomalous 182W. These data, together with data on global OIB, show that the highest-3He/4He and the largest-magnitude 182W anomalies are found only in geochemically depleted mantle domains-with high 143Nd/144Nd and low 206Pb/204Pb-lacking strong signatures of recycled materials. In contrast, OIB with the strongest signatures associated with recycled materials have low 3He/4He and lack anomalous 182W. These observations provide important clues regarding the survival of the ancient He and W signatures in Earth's mantle. We show that high-3He/4He mantle domains with anomalous 182W have low W and 4He concentrations compared to recycled materials and are therefore highly susceptible to being overprinted with low 3He/4He and normal (not anomalous) 182W characteristic of subducted crust. Thus, high 3He/4He and anomalous 182W are preserved exclusively in mantle domains least modified by recycled crust. This model places the long-term preservation of ancient high 3He/4He and anomalous 182W in the geodynamic context of crustal subduction and recycling and informs on survival of other early-formed heterogeneities in Earth's interior.
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12
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Timmerman S, Honda M, Burnham AD, Amelin Y, Woodland S, Pearson DG, Jaques AL, Le Losq C, Bennett VC, Bulanova GP, Smith CB, Harris JW, Tohver E. Primordial and recycled helium isotope signatures in the mantle transition zone. Science 2019; 365:692-694. [PMID: 31416962 DOI: 10.1126/science.aax5293] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 07/16/2019] [Indexed: 11/02/2022]
Abstract
Isotope compositions of basalts provide information about the chemical reservoirs in Earth's interior and play a critical role in defining models of Earth's structure. However, the helium isotope signature of the mantle below depths of a few hundred kilometers has been difficult to measure directly. This information is a vital baseline for understanding helium isotopes in erupted basalts. We measured He-Sr-Pb isotope ratios in superdeep diamond fluid inclusions from the transition zone (depth of 410 to 660 kilometers) unaffected by degassing and shallow crustal contamination. We found extreme He-C-Pb-Sr isotope variability, with high 3He/4He ratios related to higher helium concentrations. This indicates that a less degassed, high-3He/4He deep mantle source infiltrates the transition zone, where it interacts with recycled material, creating the diverse compositions recorded in ocean island basalts.
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Affiliation(s)
- S Timmerman
- Research School of Earth Sciences, Australian National University, 142 Mills Road, Acton, ACT 2601, Australia.
| | - M Honda
- Research School of Earth Sciences, Australian National University, 142 Mills Road, Acton, ACT 2601, Australia
| | - A D Burnham
- Research School of Earth Sciences, Australian National University, 142 Mills Road, Acton, ACT 2601, Australia
| | - Y Amelin
- Research School of Earth Sciences, Australian National University, 142 Mills Road, Acton, ACT 2601, Australia
| | - S Woodland
- Earth and Atmospheric Sciences, University of Alberta, 116 Street and 85 Avenue, Edmonton, Alberta T6G 2R3, Canada
| | - D G Pearson
- Earth and Atmospheric Sciences, University of Alberta, 116 Street and 85 Avenue, Edmonton, Alberta T6G 2R3, Canada
| | - A L Jaques
- Research School of Earth Sciences, Australian National University, 142 Mills Road, Acton, ACT 2601, Australia
| | - C Le Losq
- Research School of Earth Sciences, Australian National University, 142 Mills Road, Acton, ACT 2601, Australia
| | - V C Bennett
- Research School of Earth Sciences, Australian National University, 142 Mills Road, Acton, ACT 2601, Australia
| | - G P Bulanova
- School of Earth Sciences, University of Bristol, Queens Road, Bristol BS8 1QU, UK
| | - C B Smith
- School of Earth Sciences, University of Bristol, Queens Road, Bristol BS8 1QU, UK
| | - J W Harris
- School of Geographical and Earth Sciences, Gregory Building, University of Glasgow, Glasgow G12 8QQ, UK
| | - E Tohver
- University of Sao Paolo, Sao Paolo, Brazil
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13
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14
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Zhang J, Lv J, Li H, Feng X, Lu C, Redfern SAT, Liu H, Chen C, Ma Y. Rare Helium-Bearing Compound FeO_{2}He Stabilized at Deep-Earth Conditions. PHYSICAL REVIEW LETTERS 2018; 121:255703. [PMID: 30608845 DOI: 10.1103/physrevlett.121.255703] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Indexed: 06/09/2023]
Abstract
There is compelling geochemical evidence for primordial helium trapped in Earth's lower mantle, but the origin and nature of the helium source remain elusive due to scarce knowledge on viable helium-bearing compounds that are extremely rare. Here we explore materials physics underlying this prominent challenge. Our structure searches in conjunction with first-principles energetic and thermodynamic calculations uncover a remarkable helium-bearing compound FeO_{2}He at high pressure-temperature conditions relevant to the core-mantle boundary. Calculated sound velocities consistent with seismic data validate FeO_{2}He as a feasible constituent in ultralow velocity zones at the lowermost mantle. These mutually corroborating findings establish the first and hitherto only helium-bearing compound viable at pertinent geophysical conditions, thus providing vital physics mechanisms and materials insights for elucidating the enigmatic helium reservoir in deep Earth.
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Affiliation(s)
- Jurong Zhang
- State Key Laboratory of Superhard Materials & Innovation Center for Computational Physics Methods and Software, College of Physics, Jilin University, Changchun 130012, China
| | - Jian Lv
- State Key Laboratory of Superhard Materials & Innovation Center for Computational Physics Methods and Software, College of Physics, Jilin University, Changchun 130012, China
| | - Hefei Li
- State Key Laboratory of Superhard Materials & Innovation Center for Computational Physics Methods and Software, College of Physics, Jilin University, Changchun 130012, China
| | - Xiaolei Feng
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai, 201203, China
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, United Kingdom
| | - Cheng Lu
- Department of Physics and Astronomy, University of Nevada, Las Vegas, Nevada 89154, USA
| | - Simon A T Redfern
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai, 201203, China
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, United Kingdom
| | - Hanyu Liu
- State Key Laboratory of Superhard Materials & Innovation Center for Computational Physics Methods and Software, College of Physics, Jilin University, Changchun 130012, China
| | - Changfeng Chen
- Department of Physics and Astronomy, University of Nevada, Las Vegas, Nevada 89154, USA
| | - Yanming Ma
- State Key Laboratory of Superhard Materials & Innovation Center for Computational Physics Methods and Software, College of Physics, Jilin University, Changchun 130012, China
- International Center of Future Science, Jilin University, Changchun 130012, China
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15
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Jackson CRM, Bennett NR, Du Z, Cottrell E, Fei Y. Early episodes of high-pressure core formation preserved in plume mantle. Nature 2018; 553:491-495. [DOI: 10.1038/nature25446] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 11/22/2017] [Indexed: 11/09/2022]
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