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Northwest Africa 10997 | |||||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 10997 This is an OFFICIAL meteorite name. Abbreviation: NWA 10997 Observed fall: No Year found: 2015 Country: Morocco Mass: ![]() | ||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 353 approved meteorites classified as LL3. [show all] Search for other: LL chondrites, LL chondrites (type 3), Ordinary chondrites, and Ordinary chondrites (type 3) | ||||||||||||||||||||||||||||||
Comments: | Approved 3 Dec 2016 | ||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 105:
Northwest Africa 10997 (NWA 10997) Morocco Purchased: 2015 April Classification: Ordinary chondrite (LL3) History: Specimen was purchased in April 2015 in Morocco by S. Tutorow, who holds the main mass. Physical characteristics: There is no fusion crust on the type specimen. The color of the stone is dark gray, with abundant chondrules that are lighter in color than the matrix. The specimen has been moderately weathered to a rust color in many areas. Petrography: (E. Bethell, CUO) Chondrules display a variety of chondrule types based on petrography and texture, including: porphyritic olivine-pyroxene chondrules, barred olivine chondrules, radial pyroxene chondrules and porphyritic pyroxene chondrules. Porphyritic olivine-pyroxene chondrules appear to be the most abundant chondrule type. Chondrule boundaries remain discernible, however most are degraded and/or fractured. The mean chondrule diameter in the thin section is 1.1±0.7 mm (n=31), extending up to 4.5 mm. Minerals exhibit undulatory extinction, yet no mosaicism was observed in any of the minerals. Moderate weathering is observed in the form of oxidation of opaques (metals) in the matrix, and along fractures in the matrix and within chondrules. Oxidation of silicates and felspar was observed. Geochemistry: (EMPA) Average mineral compositions (by mol %) for pyroxene are Fs15.8±11.2Wo2.7±6.6 (n=11), olivine Fa26.1±10.2 (n=13), and plagioclase feldspar An40.2±20.6Ab55.5±18.2Or4.3±2.9 (n=8). Cr2O3 abundances in ferroan olivine, mean 0.05±0.03 wt.%. Classification: LL3. Suggested sub-type >3.2 from Cr2O3 analyses. Specimens: 20.4 g including a polished mount and thin section at UWO. The remaining mass is with S. Tutorow. | ||||||||||||||||||||||||||||||
Data from: MB105 Table 0 Line 0: |
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Institutions and collections |
UWO: University of Western Ontario, Department of Earth Sciences, BGS 1026, 1151 Richmond St. N, London, Ontario, Canada N6A 5B7, Canada (institutional address; updated 18 Jul 2015) CUO: Department of Earth Sciences Carleton University 1125 Colonel By Drive Ottawa, Ontario, K1S 5B6, Canada (institutional address; updated 3 Dec 2016) |
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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 1548 approved meteorites from Morocco (plus 22 unapproved names) (plus 1 impact crater) |