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Liu CZ, Dick HJ, Mitchell RN, Wei W, Zhang ZY, Hofmann AW, Yang JF, Li Y. Archean cratonic mantle recycled at a mid-ocean ridge. SCIENCE ADVANCES 2022; 8:eabn6749. [PMID: 35648865 PMCID: PMC9159695 DOI: 10.1126/sciadv.abn6749] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 04/15/2022] [Indexed: 05/26/2023]
Abstract
Basalts and mantle peridotites of mid-ocean ridges are thought to sample Earth's upper mantle. Osmium isotopes of abyssal peridotites uniquely preserve melt extraction events throughout Earth history, but existing records only indicate ages up to ~2 billion years (Ga) ago. Thus, the memory of the suspected large volumes of mantle lithosphere that existed in Archean time (>2.5 Ga) has apparently been lost somehow. We report abyssal peridotites with melt-depletion ages up to 2.8 Ga, documented by extremely unradiogenic 187Os/188Os ratios (to as low as 0.1095) and refractory major elements that compositionally resemble the deep keels of Archean cratons. These oceanic rocks were thus derived from the once-extensive Archean continental keels that have been dislodged and recycled back into the mantle, the feasibility of which we confirm with numerical modeling. This unexpected connection between young oceanic and ancient continental lithosphere indicates an underappreciated degree of compositional recycling over time.
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Affiliation(s)
- Chuan-Zhou Liu
- State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
- Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061, China
- CAS Center for Excellence in Deep Earth Sciences, Guangzhou 510640, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Henry J.B. Dick
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Ross N. Mitchell
- State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Wu Wei
- State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhen-Yu Zhang
- State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | | | - Jian-Feng Yang
- State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Yang Li
- State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
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Karunakaran C, Jayabharathi J, Jayamoorthy K. Fluorescence quenching of organic molecule by insulator. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 112:417-421. [PMID: 23707997 DOI: 10.1016/j.saa.2013.04.093] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 04/12/2013] [Accepted: 04/24/2013] [Indexed: 06/02/2023]
Abstract
A new kind of fluorophore 2-(4-fluorophenyl)-1-phenyl-1H-benzo[d]imidazole (FPPBI) has been synthesized and characterized by (1)H NMR, (13)C NMR, mass spectral studies and single crystal XRD. The energy transfer from FPPBI to Al2O3 nanocrystals has been studied by absorption, fluorescence and lifetime spectroscopic methods. The association between nanoparticles and FPPBI is explained from both absorption and fluorescence quenching data. The distance between FPPBI and Al2O3 as well as the critical energy transfer distance has been deduced.
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Affiliation(s)
- C Karunakaran
- Department of Chemistry, Annamalai University, Annamalainagar 608 002, Tamilnadu, India
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Huang Q, Shi R, Liu D, Zhang X, Fan S, Ding L. Os isotopic evidence for a carbonaceous chondritic mantle source for the Nagqu ophiolite from Tibet and its implications. CHINESE SCIENCE BULLETIN-CHINESE 2012. [DOI: 10.1007/s11434-012-5384-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Liu CZ, Snow JE, Hellebrand E, Brügmann G, von der Handt A, Büchl A, Hofmann AW. Ancient, highly heterogeneous mantle beneath Gakkel ridge, Arctic Ocean. Nature 2008; 452:311-6. [PMID: 18354475 DOI: 10.1038/nature06688] [Citation(s) in RCA: 248] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Accepted: 01/08/2008] [Indexed: 11/09/2022]
Abstract
The Earth's mantle beneath ocean ridges is widely thought to be depleted by previous melt extraction, but well homogenized by convective stirring. This inference of homogeneity has been complicated by the occurrence of portions enriched in incompatible elements. Here we show that some refractory abyssal peridotites from the ultraslow-spreading Gakkel ridge (Arctic Ocean) have very depleted 187Os/188Os ratios with model ages up to 2 billion years, implying the long-term preservation of refractory domains in the asthenospheric mantle rather than their erasure by mantle convection. The refractory domains would not be sampled by mid-ocean-ridge basalts because they contribute little to the genesis of magmas. We thus suggest that the upwelling mantle beneath mid-ocean ridges is highly heterogeneous, which makes it difficult to constrain its composition by mid-ocean-ridge basalts alone. Furthermore, the existence of ancient domains in oceanic mantle suggests that using osmium model ages to constrain the evolution of continental lithosphere should be approached with caution.
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Affiliation(s)
- Chuan-Zhou Liu
- State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China.
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Pearson DG, Parman SW, Nowell GM. A link between large mantle melting events and continent growth seen in osmium isotopes. Nature 2007; 449:202-5. [PMID: 17851521 DOI: 10.1038/nature06122] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Accepted: 07/26/2007] [Indexed: 11/09/2022]
Abstract
Although Earth's continental crust is thought to have been derived from the mantle, the timing and mode of crust formation have proven to be elusive issues. The area of preserved crust diminishes markedly with age, and this can be interpreted as being the result of either the progressive accumulation of new crust or the tectonic recycling of old crust. However, there is a disproportionate amount of crust of certain ages, with the main peaks being 1.2, 1.9, 2.7 and 3.3 billion years old; this has led to a third model in which the crust has grown through time in pulses, although peaks in continental crust ages could also record preferential preservation. The 187Re-187Os decay system is unique in its ability to track melt depletion events within the mantle and could therefore potentially link the crust and mantle differentiation records. Here we employ a laser ablation technique to analyse large numbers of osmium alloy grains to quantify the distribution of depletion ages in the Earth's upper mantle. Statistical analysis of these data, combined with other samples of the upper mantle, show that depletion ages are not evenly distributed but cluster in distinct periods, around 1.2, 1.9 and 2.7 billion years. These mantle depletion events coincide with peaks in the generation of continental crust and so provide evidence of coupled, global and pulsed mantle-crust differentiation, lending strong support to pulsed models of continental growth by means of large-scale mantle melting events.
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Affiliation(s)
- D G Pearson
- Northern Centre for Isotopic and Elemental Tracing, Department of Earth Sciences, Durham University, South Road, Durham DH1 4QE, UK.
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Meibom A, Frei R, Sleep NH. Osmium isotopic compositions of Os-rich platinum group element alloys from the Klamath and Siskiyou Mountains. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003jb002602] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Anders Meibom
- Geological and Environmental Sciences; Stanford University; Stanford California USA
| | - Robert Frei
- Geological Institute; University of Copenhagen; Copenhagen Denmark
| | - Norman H. Sleep
- Department of Geophysics; Stanford University; Stanford California USA
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Stern RJ, Fouch MJ, Klemperer SL. An overview of the Izu-Bonin-Mariana subduction factory. INSIDE THE SUBDUCTION FACTORY 2003. [DOI: 10.1029/138gm10] [Citation(s) in RCA: 183] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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Meibom A, Sleep NH, Chamberlain CP, Coleman RG, Frei R, Hren MT, Wooden JL. Re-Os isotopic evidence for long-lived heterogeneity and equilibration processes in the Earth's upper mantle. Nature 2002; 419:705-8. [PMID: 12384694 DOI: 10.1038/nature01067] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2002] [Accepted: 08/06/2002] [Indexed: 11/08/2022]
Abstract
The geochemical composition of the Earth's upper mantle is thought to reflect 4.5 billion years of melt extraction, as well as the recycling of crustal materials. The fractionation of rhenium and osmium during partial melting in the upper mantle makes the Re-Os isotopic system well suited for tracing the extraction of melt and recycling of the resulting mid-ocean-ridge basalt. Here we report osmium isotope compositions of more than 700 osmium-rich platinum-group element alloys derived from the upper mantle. The osmium isotopic data form a wide, essentially gaussian distribution, demonstrating that, with respect to Re-Os isotope systematics, the upper mantle is extremely heterogeneous. As depleted and enriched domains can apparently remain unequilibrated on a timescale of billions of years, effective equilibration seems to require high degrees of partial melting, such as occur under mid-ocean ridges or in back-arc settings, where percolating melts enhance the mobility of both osmium and rhenium. We infer that the gaussian shape of the osmium isotope distribution is the signature of a random mixing process between depleted and enriched domains, resulting from a 'plum pudding' distribution in the upper mantle, rather than from individual melt depletion events.
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Affiliation(s)
- Anders Meibom
- Geological and Environmental Sciences, 320 Lomita Mall, Stanford University, California 94305, USA.
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Abstract
Iridosmine grains from placer deposits associated with peridotite-bearing ophiolites in the Klamath mountains have extremely radiogenic 186Os/188Os ratios and old Re-Os minimum ages, from 256 to 2644 million years. This indicates the existence of an ancient platinum group element reservoir with a supra-chondritic Pt/Os ratio. Such a ratio may be produced in the outer core as a result of inner core crystallization that fractionates Os from Pt. However, if the iridosmine Os isotopic compositions are a signature of the outer core, then the inner core must have formed very early, within several hundred million years after the accretion of Earth.
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Affiliation(s)
- Anders Meibom
- Geological and Environmental Sciences, 320 Lomita Mall, Stanford University, CA 94305-2115, USA.
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