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Northwest Africa 8649 | |||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 8649 This is an OFFICIAL meteorite name. Abbreviation: NWA 8649 Observed fall: No Year found: 2014 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 5 approved meteorites classified as LL3.05. [show all] Search for other: LL chondrites, LL chondrites (type 3), Ordinary chondrites, and Ordinary chondrites (type 3) | ||||||||||||||||||||||||||||||
Comments: | Approved 3 Dec 2014 | ||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 103:
Northwest Africa 8649 (NWA 8649) (Northwest Africa) Purchased: 2014 Classification: Ordinary chondrite (LL3.05) History: Purchased by Aziz Habibi in Morocco, 2014. Physical characteristics: A single stone with fusion crust, weathered exterior. Saw cut reveals many densely packed chondrules of variable size; iron-oxidation present. Petrography: (C. Agee, UNM) Microprobe examination of a polished mount and polished deposit sample shows numerous unequilibrated chondrules, apparent mean diameter 602±386 μm (n=105), many with porphyritic, igneously zoned olivines and pyroxenes, most with glass or mesostasis. Abundant fine-grained matrix throughout. Geochemistry: (C. Agee, N. Muttik, UNM) All chondrule olivine Fa16.9±8.7 (Fa0.8-39.4, n=92); ferroan olivine Fa17.5±8.4, Fe/Mn=46±17, Cr2O3=0.41±0.15 wt%, n=88; low-Ca pyroxene Fs13.3±9.2Wo1.1±1.1, Fe/Mn=28±19, n=47; pigeonite Fs17.3±5.4Wo8.9±2.8, Fe/Mn=29±19, n=3; high-Ca pyroxene Fs17.8±15.1Wo28.8±6.0, Fe/Mn=13±11, n=5. Oxygen isotopes (K. Ziegler, UNM) 12 acid-washed samples of 1.5, 2.1, 1.6, 2.1, 1.8, 1.4, 1.3, 1.3, 2.3, 1.6, 2.1, and 3.5 mg gave δ17O = 2.875, 3.300, 3.713, 2.938, 2.543, 2.623, 3.249, 2.807, 3.217, 3.302, 3.563, 3.518, δ18O = 4.896, 5.022, 5.094, 4.609, 4.203, 4.464, 4.779, 4.639, 4.669, 4.585, 5.659, 5.766, Δ17O = 0.290, 0.648, 1.023, 0.504, 0.324, 0.266, 0.726, 0.358, 0.752, 0.881, 0.575, 0.474 (linearized, all permil). Classification: Ordinary chondrite (LL3.05), type 3.05 based on ferroan olivine mean Cr2O3 content and sigma from Grossman and Brearley (2005), similar values to MET 00526. Oxygen isotopes appear to be relatively heterogeneous and fall within the same range of δ17O and δ18O as NWA 7731 (Ziegler et al., LPSC, 2014). Weathering grade (W3). Low shock stage. Specimens: 53.4 g including a probe mount on deposit at UNM, Aziz Habibi holds the main mass. | ||||||||||||||||||||||||||||||
Bibliography: |
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Data from: MB103 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||||||||
Institutions and collections |
UNM: Institute of Meteoritics
MSC03 2050
University of New Mexico
Albuquerque NM 87131-1126
USA, United States; Website (institutional address; updated 12 Feb 2015) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 103, MAPS 52, 1014, May 2017, http://onlinelibrary.wiley.com/doi/10.1111/maps.12888/full
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Geography: |
Statistics: This is 1 of 9368 approved meteorites from (Northwest Africa) (plus 1875 unapproved names) |