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Northwest Africa 8661 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 8661 This is an OFFICIAL meteorite name. Abbreviation: NWA 8661 Observed fall: No Year found: 2011 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 587 approved meteorites (plus 1 unapproved name) classified as Eucrite. [show all] Search for other: Achondrites, Eucrites, and HED achondrites | ||||||||||||||||||||||||||||
Comments: | Approved 18 Feb 2015 | ||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 104:
Northwest Africa 8661 (NWA 8661) (Northwest Africa) Purchased: June 2011 Classification: HED achondrite (Eucrite) Petrography: (P. Warren, UCLA) This eucrite shows a typical medium-subophitic texture of an unbrecciated noncumulate eucrite, except pyroxene shows no perciptible exsolution. Minor Fe-metal. Geochemistry: Pyroxene, starting from En61Wo7 cores, shows continuous zoning toward Mg-poor and Ca-diverse compositions such as En6Wo13, En6Wo32. Average pyroxene En37.8±17.6Wo16.1±8.6, FeO/MnO wt. ratio 29.8±2.7, n=60; plagioclase An80.5±2.7, n=45. Oxygen isotopes: (I. Kohl and E. Young, UCLA) δ17O 1.868, δ18O 3.914, Δ17O -0.209 (all normalized). EPMA, in wt.%, derived from a 0.28 g powder) SiO2 49.5, TiO2 1.28, Al2O3 11.5, Cr2O3 0.24, MgO 5.5, FeO 18.2, MnO 0.51; mg# 0.349. Classification: Eucrite (unbrecciated). Low thermal metamorphism. | ||||||||||||||||||||||||||||
Data from: MB104 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||||||
Institutions and collections |
UCLA: Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 90095-1567, United States (institutional address; updated 17 Oct 2011) Hmani: A. Hmani Moroccan Imports, 13 rue Jules Hardouin Mansart, 92600 Asnières, France (private address) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 104, MAPS 52, 2284, Octover 2017, http://onlinelibrary.wiley.com/doi/10.1111/maps.12930/full
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Geography: |
Statistics: This is 1 of 9305 approved meteorites from (Northwest Africa) (plus 1873 unapproved names) |