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Northwest Africa 8738 | |||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 8738 This is an OFFICIAL meteorite name. Abbreviation: NWA 8738 Observed fall: No Year found: 2009 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 33 approved meteorites classified as LL3-6. [show all] Search for other: LL chondrites, LL chondrites (type 3), Ordinary chondrites, and Ordinary chondrites (type 3) | ||||||||||||||||||||||||||||||
Comments: | Approved 31 Mar 2016 | ||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 105:
Northwest Africa 8738 (NWA 8738) (Northwest Africa) Purchased: 2009 Classification: Ordinary chondrite (LL3-6) History: Purchased by Blaine Reed in Tucson, 2009. Physical characteristics: Four fragments. Saw cuts show brecciated texture, dark and light clasts set in a light-gray groundmass, scattered metal/sulfide grains. Petrography: (C. Agee) Microprobe examination of a polished mount reveals a polymict breccia with at least three distinct lithologies corresponding to LL3, LL6, and L6. Type 6 is ~75%, type 3 is ~25%. The type 3 lithology has some PO chondrules with igneous zoning, also PP chondrules with enstatitic pyroxenes, BO chondrules, all with mesostasis or glass, whereas the type 6 lithologies have a few relict chondrules, and appear to be mostly recrystallized, with equilibrated olivines and pyroxenes, and plagioclase >100 μm. Ubiquitous troilite, kamacite, chromite, and Cl-rich apatite. Geochemistry: (C. Agee, UNM) L6 component: olivine 25.5±0.2, Fe/Mn=50±3, n=4; low-Ca pyroxene Fs22.7±0.4Wo1.2±0.4, Fe/Mn=33±1, n=4. LL6 component: olivine 29.4±0.9, Fe/Mn=60±3, n=17; low-Ca pyroxene Fs25.2±0.0Wo1.2±0.1, Fe/Mn=38±0, n=3. LL3 component: porphyritic pyroxene chondrule Fs4.4±0.4Wo0.2±0.1, Fe/Mn=12±1, n=4. Random olivines range Fa16.5-29.9, Fa25.8±5.2, Fe/Mn=55±9, n=10. Classification: Ordinary chondrite (LL3-6), breccia of LL3, LL6, and L6 components, weathering grade W1, shock stage S4. Specimens: 23.6 g including a probe mount on deposit at UNM, Reed holds the main mass. | ||||||||||||||||||||||||||||||
Data from: MB105 Table 0 Line 0: |
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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) Reed: Blaine Reed, P.O. Box 1141, Delta, CO 81416, United States; Website (private address) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 105, MAPS 52, 2411, September 2017. http://onlinelibrary.wiley.com/doi/10.1111/maps.12944/full
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Geography: |
Statistics: This is 1 of 8495 approved meteorites from (Northwest Africa) (plus 1899 unapproved names) |