SCIENCE CHINA Information Sciences, Volume 63 , Issue 4 : 140902(2020) https://doi.org/10.1007/s11432-019-2809-3

Petrography and chronology of lunar meteorite Northwest Africa 6950

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  • ReceivedJun 3, 2019
  • AcceptedJan 19, 2020
  • PublishedMar 9, 2020



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  • Figure 1

    The BSE image of Northwest Africa (NWA) 6950.

  • Figure 2

    The BSE images of representative areas in NWA 6950. (a) Local details of the rock; (b) morphology of some accessory minerals in the rock; (c) a SIMV-shock induced melt vein in the stone; (d) volcanic glass. Ol: olivine, Pgt: pigeonite, MSK: maskelynite, Apa: apatite, Bad: baddeleyite, ilm: ilmenite, Gl: glass.

  • Table 1   Compositions of major elements of phosphate from NWA 6950$^{\rm~a)}$
    Phosphate (wt.%)Pho-1Pho-2Pho-3Pho-4Pho-5Pho-6Pho-7Pho-8Pho-9Pho-10Pho-11Pho-12

    a) Apa: Apatite; Mrl: merrillite; bd: below detection limit.

  • Table 2   Summary of isotopic ages (in Ma) of NWA 773 and its paired lunar meteorites$^{\rm~a)}$
    SampleAge (Ma)MethodMaterialRef.
    3129$\pm$11 (95% conf.)Pb-Pbbaddeleyite[5]
    NWA 7732865$\pm$31 (2$\sigma$)Sm-NdWhole rock[18]
    2670$\pm$10 (2$\sigma$)Ar-ArWhole rock[17]
    NWA 31602650$\pm$40 (2$\sigma$)Ar-ArWhole rock[36]
    NWA 31703118$\pm$14 (95% conf.)Pb-Pbbaddeleyite[5]
    NWA 70073106$\pm$22 (95% conf.)Pb-Pbbaddeleyite[5]
    3100$\pm$16 (95% conf.)Pb-Pbbaddeleyite[4]
    NWA 69503119$\pm$18 (95% conf.)Pb-PbphosphateThis study
    3119$\pm$16 (95% conf.)Pb-PbbaddeleyiteThis study
    3123$\pm$7 (2$\sigma$)Pb-Pbbaddeleyite[25]
    NWA 29773100$\pm$50 (2$\sigma$)Sm-NdWhole rock[24]
    3290$\pm$110 (2$\sigma$)Rb-SrWhole rock[24]